PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia is the infection of the lung parenchyma, resulting from the spread of pathogens and accompanied by the host inflammatory response. This condition is the most common infectious cause of death. Multiple organisms cause pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia, including bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology (of which StreptococcusStreptococcusStreptococcus is one of the two medically important genera of gram-positive cocci, the other being Staphylococcus. Streptococci are identified as different species on blood agar on the basis of their hemolytic pattern and sensitivity to optochin and bacitracin. There are many pathogenic species of streptococci, including S. pyogenes, S. agalactiae, S. pneumoniae, and the viridans streptococci.Streptococcus pneumoniae is the most common), virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology, and fungiFungiA kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Mycology. When pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia is acquired outside the hospital setting, it is classified as community-acquired pneumoniaCommunity-Acquired PneumoniaPneumonia in Children (CAP). Common symptoms include feverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, chillsChillsThe sudden sensation of being cold. It may be accompanied by shivering.Fever, cough, chest painPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways, and dyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea. Chest X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests usually shows consolidationConsolidationPulmonary Function Tests and/or infiltrates. Diagnosis can be made with clinical presentation and imaging, but in severe cases, microbiological testing (sputum Gram stainGram stainKlebsiella and cultures, molecular testing) and routine blood tests are needed. Empiric treatment with antibiotics is recommended, with regimen depending on the setting, risk factors for multidrug resistantMultidrug resistantResistant to at least 1 agent in > 3 antibiotic categoriesPseudomonas organisms, and individual comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus. IdentificationIdentificationDefense Mechanisms of the causative pathogen helps narrow down the antibiotics. Preventive measures include vaccinations (pneumococcal and influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza) and smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases cessation.
PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia is the infection of the lung parenchyma.
Types of pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Classification based on the site where infection was acquired:[1,2,8]
Community-acquired pneumoniaCommunity-Acquired PneumoniaPneumonia in Children (CAP): pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia acquired outside the hospital setting
Lung infectionLung infectionPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia acquired 48 hours after admission into the hospital (infection was not incubating at the time of admission)
Not associated with mechanical ventilationVentilationThe total volume of gas inspired or expired per unit of time, usually measured in liters per minute.Ventilation: Mechanics of Breathing
Ventilator-associated pneumoniaVentilator-Associated PneumoniaMultidrug-resistant Organisms and Nosocomial Infections: pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia acquired 48 hours after endotracheal intubationIntubationPeritonsillar Abscess
Notable update in the classification regarding health care–associated pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia (HCAP):[15]
Retired term
Was defined as pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia in individuals who had healthcare exposure (e.g., hospitalized, resident in a long-term care facility)
Encompassed a large group labeled as high risk for multi-drug resistant organisms (MDRO), and this led to significant use of broad-spectrumBroad-SpectrumFluoroquinolones antibiotics
Further studies showed that MDROs were not common in this population.[16]
The concept of HCAP is NOT used in the most recent US guidelines:[13]
To reduce use of unnecessary antibiotics
To decrease antibiotic resistanceResistancePhysiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.Ventilation: Mechanics of Breathing
Classification by etiology:[17,18]
Aspiration pneumoniaAspiration pneumoniaA type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper respiratory tract.Pneumonia: infectious process developing due to the entry of gastric or oropharyngeal contents (containing pathogenic bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology) into the lower airways
“Typical” pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:
Lung infectionLung infectionPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia generally affecting the lobes (lobar) and/or surrounding tissues of the airways (bronchial)
Has the usual presentation of pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia: feverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, chillsChillsThe sudden sensation of being cold. It may be accompanied by shivering.Fever, cough
Caused by the typical bacterial organisms, such as StreptococcusStreptococcusStreptococcus is one of the two medically important genera of gram-positive cocci, the other being Staphylococcus. Streptococci are identified as different species on blood agar on the basis of their hemolytic pattern and sensitivity to optochin and bacitracin. There are many pathogenic species of streptococci, including S. pyogenes, S. agalactiae, S. pneumoniae, and the viridans streptococci.Streptococcus pneumoniae and Haemophilus influenzaeHaemophilus InfluenzaeA species of Haemophilus found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through viii.Haemophilus
PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia caused by atypical organisms (Mycoplasma pneumoniaeMycoplasma pneumoniaeShort filamentous organism of the genus mycoplasma, which binds firmly to the cells of the respiratory epithelium. It is one of the etiologic agents of non-viral primary atypical pneumonia in man.Mycoplasma, Chlamydia pneumoniaeChlamydia pneumoniaeA species of chlamydophila that causes acute respiratory infection, especially atypical pneumonia, in humans, horses, and koalas.Chlamydia, Chlamydia psittaciChlamydia psittaciA genus of chlamydophila infecting primarily birds. It contains eight known serovars, some of which infect more than one type of host, including humans.Chlamydia, Coxiella burnetiiCoxiella burnetiiA species of gram-negative bacteria that grows preferentially in the vacuoles of the host cell. It is the etiological agent of q fever.Coxiella/Q Fever)
Organisms involved are not detected by standard microbiological methods.
Additionally, milder symptoms are noted compared to the pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia due to S. pneumoniae.
Epidemiology[8]
General:
Most common cause of death due to infection in the United States
Higher incidenceIncidenceThe number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time.Measures of Disease Frequency and mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate in advanced age
CAP:
80% of CAP cases are treated as outpatients.
Most common cause of death from infection in patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship > 65 years
Almost 1 out of 5 CAP inpatients are rehospitalized within 1 month.
BacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology (typical):
StreptococcusStreptococcusStreptococcus is one of the two medically important genera of gram-positive cocci, the other being Staphylococcus. Streptococci are identified as different species on blood agar on the basis of their hemolytic pattern and sensitivity to optochin and bacitracin. There are many pathogenic species of streptococci, including S. pyogenes, S. agalactiae, S. pneumoniae, and the viridans streptococci.Streptococcus pneumoniae (most common bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology)
Haemophilus influenzaeHaemophilus InfluenzaeA species of Haemophilus found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through viii.Haemophilus(2nd most common)
Moraxella catarrhalisMoraxella catarrhalisGram-negative aerobic cocci of low virulence that colonize the nasopharynx and occasionally cause meningitis; bacteremia; empyema; pericarditis; and pneumonia.Moraxella
Staphylococcus aureusStaphylococcus aureusPotentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Brain Abscess
Group A streptococci
Aerobic gram-negative bacteriagram-negative bacteriaBacteria which lose crystal violet stain but are stained pink when treated by gram’s method.Bacteriology(e.g.,Pseudomonas aeruginosaPseudomonas aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas, EnterobacteriaceaeEnterobacteriaceaeA family of gram-negative, facultatively anaerobic, rod-shaped bacteria that do not form endospores. Its organisms are distributed worldwide with some being saprophytes and others being plant and animal parasites. Many species are of considerable economic importance due to their pathogenic effects on agriculture and livestock.Cephalosporinssuch as KlebsiellaKlebsiellaKlebsiella are encapsulated gram-negative, lactose-fermenting bacilli. They form pink colonies on MacConkey agar due to lactose fermentation. The main virulence factor is a polysaccharide capsule. Klebsiella pneumoniae is the most important pathogenic species.Klebsiellaspp. or Escherichia coliEscherichia coliThe gram-negative bacterium Escherichia coli is a key component of the human gut microbiota. Most strains of E. coli are avirulent, but occasionally they escape the GI tract, infecting the urinary tract and other sites. Less common strains of E. coli are able to cause disease within the GI tract, most commonly presenting as abdominal pain and diarrhea. Escherichia coli)
MicroaerophilicMicroaerophilicHelicobacterbacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology and anaerobesAnaerobesLincosamides (noted in aspiration)
Mycoplasma pneumoniaeMycoplasma pneumoniaeShort filamentous organism of the genus mycoplasma, which binds firmly to the cells of the respiratory epithelium. It is one of the etiologic agents of non-viral primary atypical pneumonia in man.Mycoplasma(most common cause of atypical pneumoniaAtypical pneumoniaMycoplasma)
LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosisspp. (transmitted via aerosolsAerosolsColloids with a gaseous dispersing phase and either liquid (fog) or solid (smoke) dispersed phase; used in fumigation or in inhalation therapy; may contain propellant agents.Coxiella/Q Fever)
Chlamydia pneumoniaeChlamydia pneumoniaeA species of chlamydophila that causes acute respiratory infection, especially atypical pneumonia, in humans, horses, and koalas.Chlamydia
Chlamydia psittaciChlamydia psittaciA genus of chlamydophila infecting primarily birds. It contains eight known serovars, some of which infect more than one type of host, including humans.Chlamydia
Coxiella burnetiiCoxiella burnetiiA species of gram-negative bacteria that grows preferentially in the vacuoles of the host cell. It is the etiological agent of q fever.Coxiella/Q Fever
Respiratory virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology:
Influenza AInfluenza AAntivirals for Influenza and B virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
Severe acute respiratory syndrome coronavirusSevere acute respiratory syndrome coronavirusA viral disorder characterized by high fever, dry cough, shortness of breath (dyspnea) or breathing difficulties, and atypical pneumonia. A virus in the genus Coronavirus is the suspected agent.Coronavirus 2 (SARS-CoV-2)
Other coronaviruses (e.g., CoV-229E, CoV-NL63)
Respiratory syncytial virusRespiratory Syncytial VirusRespiratory syncytial virus (RSV) is an enveloped, single-stranded, linear, negative-sense RNA virus of the family Paramyxoviridae and the genus Orthopneumovirus. Two subtypes (A and B) are present in outbreaks, but type A causes more severe disease. Respiratory syncytial virus causes infections of the lungs and respiratory tract.Respiratory Syncytial Virus
Adenoviruses
Rhinoviruses
Parainfluenza virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
Table: Common pathogens detected based on the site of care[2,14]
Outpatient
Non-ICU Inpatient
ICUICUHospital units providing continuous surveillance and care to acutely ill patients.West Nile Virus
S. pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
M. pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Respiratory virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
S. pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
M. pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
H. influenzaeH. influenzaeA species of Haemophilus found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.Haemophilus
Respiratory virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosis spp.
S. pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Staphylococcus aureusStaphylococcus aureusPotentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Brain Abscess
H. influenzaeH. influenzaeA species of Haemophilus found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.Haemophilus
Respiratory virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
Risk factors[1,2,8]
General:
Ages > 65 years and < 2 years
Immunosuppression
Chronic conditions (especially cardiopulmonary diseases, asthmaAsthmaAsthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma)
Reduced gag/cough reflex
SmokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases
AlcoholismAlcoholismA primary, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over drinking, preoccupation with the drug alcohol, use of alcohol despite adverse consequences, and distortions in thinking, most notably denial. Each of these symptoms may be continuous or periodic.Wernicke Encephalopathy and Korsakoff Syndrome
Specific:
Common organisms and specific risk factors:
S. pneumoniae: dementiaDementiaMajor neurocognitive disorders (NCD), also known as dementia, are a group of diseases characterized by decline in a person’s memory and executive function. These disorders are progressive and persistent diseases that are the leading cause of disability among elderly people worldwide.Major Neurocognitive Disorders, seizure disorders, heart failureHeart FailureA heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction.Total Anomalous Pulmonary Venous Return (TAPVR), cerebrovascular disease, alcoholismAlcoholismA primary, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over drinking, preoccupation with the drug alcohol, use of alcohol despite adverse consequences, and distortions in thinking, most notably denial. Each of these symptoms may be continuous or periodic.Wernicke Encephalopathy and Korsakoff Syndrome, smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases, COPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD), HIVHIVAnti-HIV Drugs
LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosis spp.: immunosuppression, diabetesDiabetesDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus, malignancyMalignancyHemothorax, HIVHIVAnti-HIV Drugs, smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases, male sexSexThe totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism.Gender Dysphoria, and a recent hotel stay or ship cruise
H. influenzaeH. influenzaeA species of Haemophilus found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.Haemophilus: smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases, COPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD)
K. pneumoniae: increased in those with aspiration risk, such as in alcohol abuse
Additional risk factors to consider:
Residence in, or travel to endemic areas with fungiFungiA kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Mycology:
CoccidioidesCoccidioidesCoccidioidomycosis, commonly known as San Joaquin Valley fever, is a fungal disease caused by Coccidioides immitis or Coccidioides posadasii. When Coccidioides spores are inhaled, they transform into spherules that result in infection. Coccidioidomycosis is also a common cause of community-acquired pneumonia and can cause severe disease in the immunocompromised.Coccidioides/Coccidioidomycosisspp.
History of specific exposures (in travel, occupation/hobby):
HistoplasmaHistoplasmaHistoplasmosis is an infection caused by Histoplasma capsulatum, a dimorphic fungus. The fungus exists as a mold at low temperatures and as yeast at high temperatures. H. capsulatum is the most common endemic fungal infection in the US and is most prevalent in the midwestern and central states along the Ohio and Mississippi River valleys.Histoplasma/Histoplasmosis spp. and bat or bird droppings
C. psittaci and birds
Travel in areas with outbreaksOutbreaksSudden increase in the incidence of a disease. The concept includes epidemics and pandemics.Influenza Viruses/Influenza:
InfluenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza (e.g., avian influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza H5N1 and H7N9)
SARS
Middle Eastern respiratory syndrome (MERS)
BioterrorismBioterrorismThe use of biological agents in terrorism. This includes the malevolent use of bacteria; viruses; or other biological toxins against people, animals; or plants.Anthrax events:
Bacillus anthracisBacillus anthracisA species of bacteria that causes anthrax in humans and animals.Anthrax(anthraxAnthraxAnthrax is an infection caused by the bacterium Bacillus anthracis, which usually targets the skin, lungs, or intestines. Anthrax is a zoonotic disease and is usually transmitted to humans from animals or through animal products. Symptoms depend on which organ system is affected. Anthrax)
Yersinia pestisYersinia pestisThe plague is a bacterial infection caused by Yersinia pestis (Y. pestis), which primarily infects rodents. The disease is transmitted to humans via a flea bite. Inhalation of infectious droplets and handling infected animals or laboratory specimens are other means of transmission. The plague has 3 forms: bubonic (most common form), septicemic, and pneumonic. Yersinia pestis/Plague (pneumonic plaguePneumonic PlagueYersinia pestis/Plague)
Coxiella burnetiiCoxiella burnetiiA species of gram-negative bacteria that grows preferentially in the vacuoles of the host cell. It is the etiological agent of q fever.Coxiella/Q Fever(Q feverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever)
LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosis spp
HantavirusHantavirusA genus of the family bunyaviridae causing hantavirus infections, first identified during the korean war. Infection is found primarily in rodents and humans. Transmission does not appear to involve arthropods. Hantaan virus is the type species.Bunyavirales and influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/InfluenzavirusVirusViruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology
Risks for multidrug-resistant organisms (MDRO), methicillin-resistant Staphylococcus aureusStaphylococcus aureusPotentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Brain Abscess (MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus) and Pseudomonas aeruginosaPseudomonas aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas:
Less commonly found in CAP but should be considered in those with comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus and healthcare exposures
Seen more in HAP and VAP
Emphasis has been placed on determining the likelihood for these infectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease due to the associated complications and the additional treatment needed.
Strong risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.StaphylococcuspneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia (see table):[1,8,16]
Prior MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus infection (strongest risk)
Known MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.StaphylococcuscolonizationColonizationBacteriology
Strong risk factors for P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.PseudomonaspneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:[1,6,8,16]
Prior PseudomonasPseudomonasPseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. Pseudomonas infection (strongest risk)
Known PseudomonasPseudomonasPseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. PseudomonascolonizationColonizationBacteriology
HospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with IV antibiotics in the past 3 months
Gram-negative rods in sputum
The 2019 American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) guidelines:[1]
Instead of broadly categorizing all who had been exposed through a health care system, the HCAP category was eliminated.
The focus now has been on identifying local etiologic data and validated risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus and P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas in deciding treatment.
Table: Risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus and P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas CAP
MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus
P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas
Strong risk factors
Prior MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus infection
Known MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.StaphylococcuscolonizationColonizationBacteriology
HospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with IV antibiotics in the past 3 months
Prior PseudomonasPseudomonasPseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. Pseudomonas infection
Known PseudomonasPseudomonasPseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. PseudomonascolonizationColonizationBacteriology
HospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with IV antibiotics in the past 3 months
Gram-negative rods in sputum
Other considered factors that increase suspicion of infection
Recent hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium or antibiotic use (especially IV antibiotics)
Necrotizing pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
EmpyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia
Men who have sexSexThe totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism.Gender Dysphoria with men
Recent hospital or long-term facility stay
Recent antibiotic use
Numerous COPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD) exacerbations treated with steroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors and/or antibiotics
Structural lung disease (cysticCysticFibrocystic ChangefibrosisFibrosisAny pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury.Bronchiolitis Obliterans, bronchiectasisBronchiectasisBronchiectasis is a chronic disease of the airways that results from permanent bronchial distortion. This results from a continuous cycle of inflammation, bronchial damage and dilation, impaired clearance of secretions, and recurrent infections. Bronchiectasis)
Transmission commonly via respiratory dropletsDropletsVaricella-Zoster Virus/Chickenpox (or aerosol) → organisms colonize the nasopharynxNasopharynxThe top portion of the pharynx situated posterior to the nose and superior to the soft palate. The nasopharynx is the posterior extension of the nasal cavities and has a respiratory function.Pharynx: Anatomy
Small-volume aspiration of pathogens such as bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology → access to, and proliferation in alveolar space → immune response through alveolar macrophagesAlveolar macrophagesRound, granular, mononuclear phagocytes found in the alveoli of the lungs. They ingest small inhaled particles resulting in degradation and presentation of the antigen to immunocompetent cells.Acute Respiratory Distress Syndrome (ARDS) → localized capillary leak and alveolar infiltration → symptoms and signs of pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Respiratory defense mechanismsDefense mechanismsDefense mechanisms are normal subconscious means of resolving inner conflicts between an individual’s subjective moral sense and their thoughts, feelings, or actions. Defense mechanisms serve to protect the self from unpleasant feelings (anxiety, shame, and/or guilt) and are divided into pathologic, immature, mature, neurotic, and other types.Defense Mechanisms that must be overcome to cause parenchymal infection:
Nasal hair and turbinatesTurbinatesThe scroll-like bony plates with curved margins on the lateral wall of the nasal cavity. Turbinates, also called nasal concha, increase the surface area of nasal cavity thus providing a mechanism for rapid warming and humidification of air as it passes to the lung.Nose Anatomy (External & Internal)
Gag and cough reflex
Tracheobronchial tree and its mucociliary lining
Alveolar macrophagesAlveolar macrophagesRound, granular, mononuclear phagocytes found in the alveoli of the lungs. They ingest small inhaled particles resulting in degradation and presentation of the antigen to immunocompetent cells.Acute Respiratory Distress Syndrome (ARDS)
Other routes:
HematogenousHematogenousHepatocellular Carcinoma (HCC) and Liver Metastases (e.g., right heart endocarditisEndocarditisEndocarditis is an inflammatory disease involving the inner lining (endometrium) of the heart, most commonly affecting the cardiac valves. Both infectious and noninfectious etiologies lead to vegetations on the valve leaflets. Patients may present with nonspecific symptoms such as fever and fatigue. Endocarditis)
Contiguous spread (pleural or mediastinal infection)
Alternative pathogenesis: A defect in the normal defense mechanismDefense mechanismUnconscious process used by an individual or a group of individuals in order to cope with impulses, feelings or ideas which are not acceptable at their conscious level; various types include reaction formation, projection and self reversal.Psychotherapy of the airways facilitates overgrowth of the normal airwayAirwayABCDE Assessment microbiota, causing pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia.
Typical pathologic phases for bacterial lobar pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:[19]
EdemaEdemaEdema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema or congestion: increase in alveolar exudateExudateExudates are fluids, cells, or other cellular substances that are slowly discharged from blood vessels usually from inflamed tissues.Pleural Effusion containing the pathogenic organism
Red hepatization: predominant presence of erythrocytesErythrocytesErythrocytes, or red blood cells (RBCs), are the most abundant cells in the blood. While erythrocytes in the fetus are initially produced in the yolk sac then the liver, the bone marrow eventually becomes the main site of production. Erythrocytes: Histology with neutrophilsNeutrophilsGranular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Innate Immunity: Phagocytes and Antigen Presentation, fibrinFibrinA protein derived from fibrinogen in the presence of thrombin, which forms part of the blood clot.Rapidly Progressive Glomerulonephritis and occasional bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology in the exudateExudateExudates are fluids, cells, or other cellular substances that are slowly discharged from blood vessels usually from inflamed tissues.Pleural Effusion, resembling the liverLiverThe liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy (“hepatization”)
Gray hepatization (successful control of infection): predominant presence of neutrophilsNeutrophilsGranular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Innate Immunity: Phagocytes and Antigen Presentation and fibrinFibrinA protein derived from fibrinogen in the presence of thrombin, which forms part of the blood clot.Rapidly Progressive Glomerulonephritis as the RBCsRBCsErythrocytes, or red blood cells (RBCs), are the most abundant cells in the blood. While erythrocytes in the fetus are initially produced in the yolk sac then the liver, the bone marrow eventually becomes the main site of production.Erythrocytes: Histology break down (↓ erythrocytesErythrocytesErythrocytes, or red blood cells (RBCs), are the most abundant cells in the blood. While erythrocytes in the fetus are initially produced in the yolk sac then the liver, the bone marrow eventually becomes the main site of production. Erythrocytes: Histology)
Resolution: predominant presence of macrophagesMacrophagesThe relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells.Innate Immunity: Phagocytes and Antigen Presentation with the clearing of neutrophilsNeutrophilsGranular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Innate Immunity: Phagocytes and Antigen Presentation and fibrinFibrinA protein derived from fibrinogen in the presence of thrombin, which forms part of the blood clot.Rapidly Progressive Glomerulonephritis
Clinical Presentation
Symptoms[2,21]
Respiratory:
Cough:
Productive (mucoid, purulent, or blood-tinged sputum)
Gross hemoptysisHemoptysisHemoptysis is defined as the expectoration of blood originating in the lower respiratory tract. Hemoptysis is a consequence of another disease process and can be classified as either life threatening or non-life threatening. Hemoptysis can result in significant morbidity and mortality due to both drowning (reduced gas exchange as the lungs fill with blood) and hemorrhagic shock. Hemoptysis (seen in MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus)
DyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea (mild to severe)
Pleuritic chest painPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways
Nonspecific symptoms:
FeverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever
FatigueFatigueThe state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.Fibromyalgia
NauseaNauseaAn unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses.Antiemetics and/or vomitingVomitingThe forcible expulsion of the contents of the stomach through the mouth.Hypokalemia
HeadacheHeadacheThe symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders.Brain Abscess
PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia in the elderly may present with confusion.
Physical examination[2,21]
TachycardiaTachycardiaAbnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.Sepsis in Children
↑ Respiratory rateRespiratory rateThe number of times an organism breathes with the lungs (respiration) per unit time, usually per minute.Pulmonary Examination and use of accessory muscles
↓ Tactile fremitusTactile FremitusPulmonary Examination and flat/dull percussionPercussionAct of striking a part with short, sharp blows as an aid in diagnosing the condition beneath the sound obtained.Pulmonary Examination → pleural effusionPleural EffusionPleural effusion refers to the accumulation of fluid between the layers of the parietal and visceral pleura. Common causes of this condition include infection, malignancy, autoimmune disorders, or volume overload. Clinical manifestations include chest pain, cough, and dyspnea. Pleural Effusion
Auscultation findings can include:
Crackles
Bronchial sounds in the periphery
Pleural friction rub
Severe cases may present with signs of septic shockSeptic shockSepsis associated with hypotension or hypoperfusion despite adequate fluid resuscitation. Perfusion abnormalities may include, but are not limited to lactic acidosis; oliguria; or acute alteration in mental status.Sepsis and Septic Shock and multiorgan failure.
The diagnosis is based on clinical findings (signs and symptoms) and imaging.
Chest X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests:
Test of choice in most cases
For clinically suspected pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia, obtain posteroanterior (PA) and lateral chest radiographs.
Findings may include:
Lobar consolidations
Interstitial infiltrates
Cavitations
Pleural effusionPleural EffusionPleural effusion refers to the accumulation of fluid between the layers of the parietal and visceral pleura. Common causes of this condition include infection, malignancy, autoimmune disorders, or volume overload. Clinical manifestations include chest pain, cough, and dyspnea. Pleural Effusion
Some patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship may require for evaluation of:
Suspected tumors
Foreign bodies
Cavitary lesions
Helpful when detection of inflammatory changes may not be apparent on X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests:
Inflammatory changes may not be evident in immunocompromisedimmunocompromisedA human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.GastroenteritispatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship.
Chronic lung disease (e.g., pulmonary fibrosisFibrosisAny pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury.Bronchiolitis Obliterans, bronchiectasisBronchiectasisBronchiectasis is a chronic disease of the airways that results from permanent bronchial distortion. This results from a continuous cycle of inflammation, bronchial damage and dilation, impaired clearance of secretions, and recurrent infections. Bronchiectasis) may obscure the visualization of infiltrates.
CT angiographyAngiographyRadiography of blood vessels after injection of a contrast medium.Cardiac Surgery may be used to rule out pulmonary embolismPulmonary EmbolismPulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism as a cause of respiratory symptoms.
Lobar pneumonia. Dense infiltration in the left lower lobe has caused a silhouette of the left cardiac border (dashed line). Air bronchogram is a typical feature of consolidation.
Image: “Chest x-ray of the patient with dense infiltration in the left lower lobe” by Ortega et al. License: CC BY 4.0, edited by Lecturio.
CT imaging of rapid progression stage. A 50-year-old female with anorexia, fatigue, muscle soreness, nasal congestion, and runny nose for 1 week, sore and itching throat for 2 days. Laboratory test: increased erythrocyte sedimentation rate (25 mm/h), normal white blood cells (4.08 × 109/L), decreased lymphocytes (0.96 × 109/ L), increased C-reaction protein (60.8 mg/L). Imaging examination: a (thin layer CT) and b (high-resolution CT) showed multiple patchy and light consolidation in both lungs and grid-like thickness of interlobular septa.
Image: “COVID19 CT chest” by Jin, Y., Cai, L., Cheng, Z. et al. License: CC BY 4.0
Necrotizing cavitating pneumonia. Chest X-ray and CT depicting necrotizing cavitating pneumonia due to Staphylococcus aureus in a 29-year-old man with acquired immunodeficiency syndrome.
Image: “Necrotizing cavitating pneumonia” by Annals of Thoracic Medicine. License: CC BY 2.0
Atypical pneumonia: mild diffuse interstitial infiltration. No lobar consolidation, effusion, or pneumothorax is observed.
Image: “Chest X-ray demonstrating interstitial infiltration” by Department of pediatrics, Ege University Faculty of Medicine, Izmir, 35100 Bornova, Turkey. License: CC BY 3.0
Determining the etiology[1,2,5,6,12,21–23]
Generally, in mild CAP being treated on an outpatient basis, microbiologic testing is not necessary except for SARS-CoV-2 and influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza (during influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza season). For inpatient management, several tests are obtained, depending on the severity, underlying illness, and epidemiologic exposures.
Sputum and blood cultures:
Not routinely obtained in the outpatient setting.
Recommended in the inpatient setting for the following:
Severe pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia (especially if the patient is intubated)
Likely infection with MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus or Pseudomonas aeruginosaPseudomonas aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas
Previously hospitalized and treated with parenteral antibiotics in the last 90 days
Appropriate antibiotic choice(s) when initial therapy fails
Determination of public health risk (e.g., LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosisis reportable)
Test for influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza:
During influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza season, testing for influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza is recommended.
Includes:
Rapid influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza molecular assay (influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenzanucleic acid amplificationNucleic acid amplificationLaboratory techniques that involve the in-vitro synthesis of many copies of DNA or RNA from one original template.Septic Arthritis test, which is preferred)
Rapid influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/InfluenzaantigenAntigenSubstances that are recognized by the immune system and induce an immune reaction.Vaccination test
In settings where resources are limited, testing priorities for SARS-CoV-2 include:
Critically ill individuals
Symptomatic healthcare workers/first responders
Symptomatic individuals who are immunosuppressed, are ≥ 65 years old, or have comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus
Symptomatic critical infrastructure workers, healthcare workers, or first responders
Pneumococcus and LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/LegionellosisantigenAntigenSubstances that are recognized by the immune system and induce an immune reaction.Vaccination:
Urinary antigenAntigenSubstances that are recognized by the immune system and induce an immune reaction.Vaccination test for detection of Legionella pneumophilaLegionella pneumophilaA species of gram-negative, aerobic bacteria that is the causative agent of legionnaires’ disease. It has been isolated from numerous environmental sites as well as from human lung tissue, respiratory secretions, and blood.Legionella/Legionellosis or pneumococcus
Urine pneumococcal antigenAntigenSubstances that are recognized by the immune system and induce an immune reaction.Vaccination: not routinely tested except in severe CAP[1,6]
UrineLegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/LegionellosisantigenAntigenSubstances that are recognized by the immune system and induce an immune reaction.Vaccination is not routinely tested, but recommended in the following:
Severe CAP
LegionellaLegionellaLegionella is a facultative intracellular, gram-negative bacilli. Legionella does not grow on common culture media because it requires certain supplementation (cysteine and iron). Legionella pneumophila (L. pneumophila) accounts for the majority of human infections.Legionella/Legionellosis outbreak in the community or travel to an area affected by an outbreak
Other respiratory virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology:
Not recommended for outpatients
Testing should be considered in hospitalized individuals in the following circumstances:
Severe CAP
ImmunocompromisedimmunocompromisedA human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.GastroenteritispatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship
VirusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology detected can vary depending on lab and test manufacturer, but may include:
Respiratory syncytial virusRespiratory Syncytial VirusRespiratory syncytial virus (RSV) is an enveloped, single-stranded, linear, negative-sense RNA virus of the family Paramyxoviridae and the genus Orthopneumovirus. Two subtypes (A and B) are present in outbreaks, but type A causes more severe disease. Respiratory syncytial virus causes infections of the lungs and respiratory tract.Respiratory Syncytial Virus (RSVRSVRespiratory syncytial virus (RSV) is an enveloped, single-stranded, linear, negative-sense RNA virus of the family Paramyxoviridae and the genus Orthopneumovirus. Two subtypes (A and B) are present in outbreaks, but type A causes more severe disease. Respiratory syncytial virus causes infections of the lungs and respiratory tract.Respiratory Syncytial Virus)
AdenovirusAdenovirusAdenovirus (member of the family Adenoviridae) is a nonenveloped, double-stranded DNA virus. Adenovirus is transmitted in a variety of ways, and it can have various presentations based on the site of entry. Presentation can include febrile pharyngitis, conjunctivitis, acute respiratory disease, atypical pneumonia, and gastroenteritis. Adenovirus
Parainfluenza virusParainfluenza virusHuman parainfluenza viruses (HPIVs) are single-stranded, linear, negative-sense RNA viruses of the family Paramyxoviridae and the genus Paramyxovirus. Human parainfluenza viruses are the 2nd most common cause of lower respiratory disease in children, after the respiratory syncytial virus.Parainfluenza Virus
RhinovirusRhinovirusRhinovirus is an acid-labile, positive-sense RNA virus of the Picornavirus family. The virus, which causes the common cold, is most often acquired through the airway via the inhalation of aerosols containing rhinovirus and fomites. Rhinovirus
Rapid nasal PCRPCRPolymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules.Polymerase Chain Reaction (PCR) or culture for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcusis obtained in:
Severe CAP
Those at risk for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus
Those with progressive deterioration
Other tests can be added depending on the indication:
Cavitary pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia → test for NocardiaNocardiaNocardia is a branching, filamentous, gram-positive bacilli. It is partially acid fast due to the presence of mycolic acids in the cell wall. Nocardia is a ubiquitous soil organism that most commonly affects immunocompromised patients. Nocardia is transmitted via inhalation of aerosolized bacteria or less commonly, via direct contact with wounds. Nocardia/Nocardiosis, tuberculosisTuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis, and other fungal organisms
ImmunocompromisedimmunocompromisedA human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.Gastroenteritis → include tests for:
Pneumocystis jiroveciPneumocystis jiroveciPneumocystis jiroveci is a yeast-like fungus causing pneumocystis pneumonia (PCP) in immunocompromised patients. Pneumocystis pneumonia is spread through airborne transmission and classically affects patients with AIDS, functioning as an AIDS-defining illness. Patients may present with insidious onset of fever, chills, dry cough, chest pain, and shortness of breath.Pneumocystis jirovecii/Pneumocystis Pneumonia (PCP)
Fungal pathogens
Less common virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology
Exposure and travel → check for zoonotic pathogens
If bronchoscopyBronchoscopyEndoscopic examination, therapy or surgery of the bronchi.Laryngomalacia and Tracheomalacia is pursued, additional multiplex molecular assays (that detect other virusesVirusesMinute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Virology and bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology) are sent.
Additional laboratory tests[1–3,6,7,14,21,23]
Mostly obtained in the hospital setting to help assess severity of illness and other underlying disorders:
CBC:
Usually, leukocytosisLeukocytosisA transient increase in the number of leukocytes in a body fluid.West Nile Virus with a leftward shift
Leukopenia and thrombocytopeniaThrombocytopeniaThrombocytopenia occurs when the platelet count is < 150,000 per microliter. The normal range for platelets is usually 150,000-450,000/µL of whole blood. Thrombocytopenia can be a result of decreased production, increased destruction, or splenic sequestration of platelets. Patients are often asymptomatic until platelet counts are < 50,000/µL. Thrombocytopenia are associated with severe CAP.
Metabolic panel:
Newly ↑ BUN and creatinine indicate poorer prognosisPrognosisA prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations.Non-Hodgkin Lymphomas.
Abnormal liver function testsLiver function testsLiver function tests, also known as hepatic function panels, are one of the most commonly performed screening blood tests. Such tests are also used to detect, evaluate, and monitor acute and chronic liver diseases.Liver Function Tests are also noted in sepsisSepsisSystemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock.Sepsis and Septic Shock.
Antibiotic therapy is not recommended if CRP is < 20 mg/L (low risk for CAP)
Repeated in hospitalized patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship if unclear clinical progress (after 48–72 hours)
Some studies indicate that the level of procalcitoninProcalcitoninNeutropenic Fever can help distinguish viral from bacterial infectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease, but sensitivity varies greatly (38%–91%).
May have some prognostic value in deciding treatment setting
Consider if patient has risk factors and/or is unresponsive to standard therapy
Directs workup needed, especially for opportunistic infectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease
Recommendations may vary depending on practice location, regional epidemiology, and availability of drug therapy. The following is a summary derived largely from the ATS/IDSA guidelines. For detailed information, ATS/IDSA guidelines (US), UK guidelines, and European guidelines are available for review.
Risk assessmentRisk assessmentThe qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences.Preoperative Care
In addition to clinical judgmentJudgmentThe process of discovering or asserting an objective or intrinsic relation between two objects or concepts; a faculty or power that enables a person to make judgments; the process of bringing to light and asserting the implicit meaning of a concept; a critical evaluation of a person or situation.Psychiatric Assessment, a validated prediction tool is recommended to determine the severity of infection and need for hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium.
Severity assessment on initial evaluation:Tools such as the PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia Severity Index (PSI) and CURB-65 (Confusion, blood UreaReAReactive arthritis is a seronegative autoimmune spondyloarthropathy that occurs in response to a previous gastrointestinal (GI) or genitourinary (GU) infection. The disease manifests as asymmetric oligoarthritis (particularly of large joints in the lower extremities), enthesopathy, dactylitis, and/or sacroiliitis.Reactive ArthritisnitrogenNitrogenAn element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Urea Cycle, Respiratory rate, Blood pressure, and age ≥ 65 years) predict 30-day mortalityMortalityAll deaths reported in a given population.Measures of Health Status from the time of diagnosis. The choice of tool varies depending on the practice location.
Preferred tool: PneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia Severity Index (PSI)[1,2,7,14]
Classifies larger portion of those with CAP as low risk, allowing safe outpatient treatment
Points are assigned based on different risk factors:
Demographics
ComorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus
Physical examination findings
Laboratory tests (e.g., arterial pHpHThe quantitative measurement of the acidity or basicity of a solution.Acid-Base Balance, blood ureaUreaA compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Urea CyclenitrogenNitrogenAn element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Urea Cycle, serum sodiumSodiumA member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23.Hyponatremia and glucoseGlucoseA primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.Lactose Intolerance, hematocritHematocritThe volume of packed red blood cells in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, anemia shows a low value; polycythemia, a high value.Neonatal Polycythemia, partial pressurePartial pressureThe pressure that would be exerted by one component of a mixture of gases if it were present alone in a container.Gas Exchange of oxygen)
Imaging (e.g., pleural effusionPleural EffusionPleural effusion refers to the accumulation of fluid between the layers of the parietal and visceral pleura. Common causes of this condition include infection, malignancy, autoimmune disorders, or volume overload. Clinical manifestations include chest pain, cough, and dyspnea. Pleural Effusion)
Total points are added and classified in to different risk classes (I–V), with higher points indicating higher mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate:
Class I or II → sent home on oral antibiotics
Class III → may be sent home on oral antibiotics or admitted for short-term monitoring and antibiotic therapy based on home environment and follow-up
Recommended by the European Society of Clinical Microbiology and Infectious Diseasesand British Thoracic Society (BTS)
Less complex than PSI
One point for each of the following:
Confusion
Blood ureaUreaA compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Urea CyclenitrogenNitrogenAn element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Urea Cycle ≥ 20 mg/dL
Respirations ≥ 30/min
Systolic blood pressure < 90 mm Hg or diastolic blood pressure < 60 mm Hg
Age ≥ 65 years
Points are added together, with higher points indicating higher mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate:
0–1 (mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate < 1%–3%) → send home on oral antibiotics
2 (mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate 9%) → short hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium for monitoring and antibiotic therapy, or supervised outpatient treatment (based on home environment and follow-up)
3–5 (mortalityMortalityAll deaths reported in a given population.Measures of Health Status rate 14%–40%) → hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium recommended, with those scoring 4–5 assessed for intensive care admission
Intensive care admission assessment (severe CAP):
ATS/IDSA criteria for defining severe CAP → presence of CAP and must meet major or minor criteria:[1,6,14]
≥ 1 of the following (major criteria):
Septic shockSeptic shockSepsis associated with hypotension or hypoperfusion despite adequate fluid resuscitation. Perfusion abnormalities may include, but are not limited to lactic acidosis; oliguria; or acute alteration in mental status.Sepsis and Septic Shock or hypotensionHypotensionHypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension requiring vasopressorsVasopressorsSepsis in Children
Respiratory failureRespiratory failureRespiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure requiring mechanical ventilationVentilationThe total volume of gas inspired or expired per unit of time, usually measured in liters per minute.Ventilation: Mechanics of Breathing
≥ 3 of the following (minor criteria):
Confusion
Respirations ≥ 30/min
HypotensionHypotensionHypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension requiring aggressive fluid management
Core temperature < 36 ℃
WBC < 4,000 cells/µL
PlateletsPlateletsPlatelets are small cell fragments involved in hemostasis. Thrombopoiesis takes place primarily in the bone marrow through a series of cell differentiation and is influenced by several cytokines. Platelets are formed after fragmentation of the megakaryocyte cytoplasm. Platelets: Histology < 100,000/µL
Blood ureaUreaA compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Urea CyclenitrogenNitrogenAn element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Urea Cycle ≥ 20 mg/dL
Partial pressurePartial pressureThe pressure that would be exerted by one component of a mixture of gases if it were present alone in a container.Gas Exchange of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ≤ 250
Multilobar pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Alternative prediction tool in determining those who would need vasopressorVasopressorAcute Cholangitis and/or mechanical ventilatory support
Most patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship used in the study were > 50 years of age, so sensitivity is reduced when used in those < 50.
Elements:
Systolic blood pressure (low or < 90 mm Hg)
Multilobar pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Albumin (hypoalbuminemiaHypoalbuminemiaA condition in which albumin level in blood (serum albumin) is below the normal range. Hypoalbuminemia may be due to decreased hepatic albumin synthesis, increased albumin catabolism, altered albumin distribution, or albumin loss through the urine (albuminuria).Nephrotic Syndrome in Children)
Respiratory rate (elevated)
Tachycardia
Confusion
Oxygenation (low)
pH (low arterial pHpHThe quantitative measurement of the acidity or basicity of a solution.Acid-Base Balance)
Overview of treatment[1,2,4,6]
Majority of those diagnosed with CAP are treated empirically.
Differences in initial treatment are affected by severity of CAP and comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus.
Serum procalcitoninProcalcitoninNeutropenic Fever levels should not influence the decision to treat pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia with antibiotics.
Outpatient treatment
Antibiotic options for patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship without comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus:[1,2,4,5,13]
AmoxicillinAmoxicillinA broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration.Penicillins
Doxycycline
AzithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides (or clarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides) → use only if pneumococcal resistanceResistancePhysiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.Ventilation: Mechanics of Breathing to macrolidesMacrolidesMacrolides and ketolides are antibiotics that inhibit bacterial protein synthesis by binding to the 50S ribosomal subunit and blocking transpeptidation. These antibiotics have a broad spectrum of antimicrobial activity but are best known for their coverage of atypical microorganisms. Macrolides and Ketolides is < 25% in the community
Antibiotic options for patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus:[1,2,13]
Examples of comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus to consider:
DiabetesDiabetesDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus mellitus
LiverLiverThe liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy disease
AspleniaAspleniaAsplenia is the absence of splenic tissue or function and can stem from several factors ranging from congenital to iatrogenic. There is a distinction between anatomic asplenia, which is due to the surgical removal of the spleen, and functional asplenia, which is due to a condition that leads to splenic atrophy, infarct, congestion, or infiltrative disease. Asplenia
Alcohol dependence
Combination therapy:
Typically includes 1 of these:
AmoxicillinAmoxicillinA broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration.Penicillins/clavulanate
Macrolide (azithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides or clarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides)
MoxifloxacinMoxifloxacinA fluoroquinolone that acts as an inhibitor of DNA topoisomerase II and is used as a broad-spectrum antibacterial agent.Fluoroquinolones
GemifloxacinGemifloxacinA naphthyridine and fluoroquinolone derivative antibacterial agent and DNA topoisomerase II inhibitor that is used for the treatment of community-acquired pneumonia and acute bacterial infections associated with chronic bronchitis.Fluoroquinolones (not available in the U.S.)
No comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus
Monotherapy
AmoxicillinAmoxicillinA broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration.Penicillins
US: 1 g 3 times daily
UK: 500 mg (or higher) 3 times daily[4]
AzithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides
500 mg on day 1
Then 250 mg daily
ClarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides
500 mg twice daily
Doxycycline
100 mg twice daily
With comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus*
AmoxicillinAmoxicillinA broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration.Penicillins–clavulanate
Options include:
500 mg/125 mg 3 times daily
875 mg/125 mg twice daily
2,000 mg/125 mg twice daily
Cefpodoxime
200 mg twice daily
Cefuroxime
500 mg twice daily
AzithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides
500 mg on day 1
Then 250 mg daily
ClarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides
MoxifloxacinMoxifloxacinA fluoroquinolone that acts as an inhibitor of DNA topoisomerase II and is used as a broad-spectrum antibacterial agent.Fluoroquinolones
400 mg daily
GemifloxacinGemifloxacinA naphthyridine and fluoroquinolone derivative antibacterial agent and DNA topoisomerase II inhibitor that is used for the treatment of community-acquired pneumonia and acute bacterial infections associated with chronic bronchitis.Fluoroquinolones
320 mg daily
*Includes chronic heart, lung, liver, or renal disease; diabetes mellitus; alcohol dependence;
malignancy; or asplenia
Inpatient treatment
Antibiotic options will depend on the severity of infection and presence of MDR organism risk factors.
Nonsevere CAP antibiotic options:
With no MDR risk factors:[1,2]
Combination therapy:
1 of the following: ampicillinAmpicillinSemi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic.Penicillins–sulbactamSulbactamA beta-lactamase inhibitor with very weak antibacterial action. The compound prevents antibiotic destruction of beta-lactam antibiotics by inhibiting beta-lactamases, thus extending their spectrum activity. Combinations of sulbactam with beta-lactam antibiotics have been used successfully for the therapy of infections caused by organisms resistant to the antibiotic alone.Cephalosporins, cefotaximeCefotaximeSemisynthetic broad-spectrum cephalosporin.Cephalosporins, ceftriaxoneCeftriaxoneA broad-spectrum cephalosporin antibiotic and cefotaxime derivative with a very long half-life and high penetrability to meninges, eyes and inner ears.Cephalosporins, or ceftarolineCeftarolineCephalosporins
Plus 1 of the following: azithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides, clarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides, or doxycycline
MoxifloxacinMoxifloxacinA fluoroquinolone that acts as an inhibitor of DNA topoisomerase II and is used as a broad-spectrum antibacterial agent.Fluoroquinolones
With ≥ 2 risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus:[1,2]
Add empiric coverage to those with prior respiratory isolation of MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus or positive culture:
VancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides
LinezolidLinezolidAn oxazolidinone and acetamide derived anti-bacterial agent and protein synthesis inhibitor that is used in the treatment of gram-positive bacterial infections of the skin and respiratory tract.Oxazolidinones
For those with prior hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with parenteral antibiotics, first obtain culture → add coverage if positive
Cultures are required to determine the need to continue therapy.
With risk factors for P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas:[1,2]
Use an antipneumococcal and antipseudomonal β-lactam in those with prior isolation of PseudomonasPseudomonasPseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. Pseudomonas or positive culture:
PiperacillinPiperacillinSemisynthetic, broad-spectrum, ampicillin derived ureidopenicillin antibiotic proposed for pseudomonas infections. It is also used in combination with other antibiotics.Penicillins–tazobactamTazobactamA penicillanic acid and sulfone derivative and potent beta-lactamase inhibitor that enhances the activity of other anti-bacterial agents against beta-lactamase producing bacteria.Cephalosporins
CefepimeCefepimeA fourth-generation cephalosporin antibacterial agent that is used in the treatment of infections, including those of the abdomen, urinary tract, respiratory tract, and skin. It is effective against pseudomonas aeruginosa and may also be used in the empiric treatment of febrile neutropenia.Cephalosporins
CeftazidimeCeftazidimeSemisynthetic, broad-spectrum antibacterial derived from cephaloridine and used especially for pseudomonas and other gram-negative infections in debilitated patients.Cephalosporins
ImipenemImipenemSemisynthetic thienamycin that has a wide spectrum of antibacterial activity against gram-negative and gram-positive aerobic and anaerobic bacteria, including many multiresistant strains. It is stable to beta-lactamases. Clinical studies have demonstrated high efficacy in the treatment of infections of various body systems. Its effectiveness is enhanced when it is administered in combination with cilastatin, a renal dipeptidase inhibitor.Carbapenems and Aztreonam
MeropenemMeropenemA thienamycin derivative antibacterial agent that is more stable to renal dehydropeptidase I than imipenem, but does not need to be given with an enzyme inhibitor such as cilastatin. It is used in the treatment of bacterial infections, including infections in immunocompromised patients.Carbapenems and Aztreonam
Alternative: aztreonamAztreonamThe carbapenems and aztreonam are both members of the bactericidal beta-lactam family of antibiotics (similar to penicillins). They work by preventing bacteria from producing their cell wall, ultimately leading to bacterial cell death. Carbapenems and Aztreonam
For those with prior hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with parenteral antibiotics, obtain culture first → add coverage if positive
Cultures are required to determine the need to continue therapy.
No risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus orP. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas
Combination therapy (antipneumococcal β-lactam plus a macrolide or doxycycline)
AmpicillinAmpicillinSemi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic.Penicillins–sulbactamSulbactamA beta-lactamase inhibitor with very weak antibacterial action. The compound prevents antibiotic destruction of beta-lactam antibiotics by inhibiting beta-lactamases, thus extending their spectrum activity. Combinations of sulbactam with beta-lactam antibiotics have been used successfully for the therapy of infections caused by organisms resistant to the antibiotic alone.Cephalosporins
CeftriaxoneCeftriaxoneA broad-spectrum cephalosporin antibiotic and cefotaxime derivative with a very long half-life and high penetrability to meninges, eyes and inner ears.Cephalosporins
AzithromycinAzithromycinA semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Macrolides and Ketolides
500 mg daily
ClarithromycinClarithromycinA semisynthetic macrolide antibiotic derived from erythromycin that is active against a variety of microorganisms. It can inhibit protein synthesis in bacteria by reversibly binding to the 50s ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation.Macrolides and Ketolides
MoxifloxacinMoxifloxacinA fluoroquinolone that acts as an inhibitor of DNA topoisomerase II and is used as a broad-spectrum antibacterial agent.Fluoroquinolones
400 mg daily
With strong risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus
Add 1 of the following for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus coverage
VancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides
LinezolidLinezolidAn oxazolidinone and acetamide derived anti-bacterial agent and protein synthesis inhibitor that is used in the treatment of gram-positive bacterial infections of the skin and respiratory tract.Oxazolidinones
600 mg every 12 hours
With strong risk factors for P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas
Use an antipneumococcal and antipseudomonal β-lactam
PiperacillinPiperacillinSemisynthetic, broad-spectrum, ampicillin derived ureidopenicillin antibiotic proposed for pseudomonas infections. It is also used in combination with other antibiotics.Penicillins–tazobactamTazobactamA penicillanic acid and sulfone derivative and potent beta-lactamase inhibitor that enhances the activity of other anti-bacterial agents against beta-lactamase producing bacteria.Cephalosporins
4.5 g every 6 hours
CefepimeCefepimeA fourth-generation cephalosporin antibacterial agent that is used in the treatment of infections, including those of the abdomen, urinary tract, respiratory tract, and skin. It is effective against pseudomonas aeruginosa and may also be used in the empiric treatment of febrile neutropenia.Cephalosporins
2 g every 8 hours
CeftazidimeCeftazidimeSemisynthetic, broad-spectrum antibacterial derived from cephaloridine and used especially for pseudomonas and other gram-negative infections in debilitated patients.Cephalosporins
2 g every 8 hours
ImipenemImipenemSemisynthetic thienamycin that has a wide spectrum of antibacterial activity against gram-negative and gram-positive aerobic and anaerobic bacteria, including many multiresistant strains. It is stable to beta-lactamases. Clinical studies have demonstrated high efficacy in the treatment of infections of various body systems. Its effectiveness is enhanced when it is administered in combination with cilastatin, a renal dipeptidase inhibitor.Carbapenems and Aztreonam
500 mg every 6 hours
MeropenemMeropenemA thienamycin derivative antibacterial agent that is more stable to renal dehydropeptidase I than imipenem, but does not need to be given with an enzyme inhibitor such as cilastatin. It is used in the treatment of bacterial infections, including infections in immunocompromised patients.Carbapenems and Aztreonam
1 g every 8 hours
AztreonamAztreonamThe carbapenems and aztreonam are both members of the bactericidal beta-lactam family of antibiotics (similar to penicillins). They work by preventing bacteria from producing their cell wall, ultimately leading to bacterial cell death. Carbapenems and Aztreonam
2 g every 8 hours
MRSA: methicillin-resistant Staphylococcus aureus
Severe CAP antibiotic regimens (use same dosing from table above):[1,2]
If no risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus or P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas, can use either:
β-lactam plus a macrolide (preferred)
β-lactam plus a respiratory fluoroquinolone
If ≥ 2 risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus or P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas are present, add appropriate coverage.
Additional considerations[1,6,23]
CAP and influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza: should be given anti-influenza treatment (e.g., oseltamivirOseltamivirAn acetamido cyclohexene that is a structural homolog of sialic acid and inhibits neuraminidase.Antivirals for Influenza) in addition to standard CAP therapy
Suspected lung abscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease or empyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia:
Add anaerobic coverage.
Note: Suspected aspiration pneumoniaAspiration pneumoniaA type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper respiratory tract.Pneumonia is not an indication for anaerobic coverage.
Other measures:
Hydration, when indicated
VasopressorsVasopressorsSepsis in Children for septic shockSeptic shockSepsis associated with hypotension or hypoperfusion despite adequate fluid resuscitation. Perfusion abnormalities may include, but are not limited to lactic acidosis; oliguria; or acute alteration in mental status.Sepsis and Septic Shock
Oxygen therapy for hypoxemiaHypoxemiaNeonatal Respiratory Distress Syndrome, and mechanical ventilationVentilationThe total volume of gas inspired or expired per unit of time, usually measured in liters per minute.Ventilation: Mechanics of Breathing for respiratory failureRespiratory failureRespiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure
CorticosteroidsCorticosteroidsChorioretinitis (methylprednisoloneMethylprednisoloneA prednisolone derivative with similar anti-inflammatory action.Immunosuppressants 0.5 mg/kg IV every 12 hours) are used only in refractory septic shockSeptic shockSepsis associated with hypotension or hypoperfusion despite adequate fluid resuscitation. Perfusion abnormalities may include, but are not limited to lactic acidosis; oliguria; or acute alteration in mental status.Sepsis and Septic Shock.
Table: Considerations in the therapy for CAP[1]
Categrory
Recommendations
CAP with influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza
Add anti-influenza treatment (e.g., oseltamivirOseltamivirAn acetamido cyclohexene that is a structural homolog of sialic acid and inhibits neuraminidase.Antivirals for Influenza 75 mg twice daily) if the patient tests positive
for influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza.
Suspected aspiration pneumoniaAspiration pneumoniaA type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper respiratory tract.Pneumonia
Anaerobic coverage is not routinely added.
Suspected lung abscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease or empyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia
Indicated in refractory septic shockSeptic shockSepsis associated with hypotension or hypoperfusion despite adequate fluid resuscitation. Perfusion abnormalities may include, but are not limited to lactic acidosis; oliguria; or acute alteration in mental status.Sepsis and Septic Shock (unresponsive to fluid support and vasopressorsVasopressorsSepsis in Children)
Typically ≥ 5 days (both outpatient and inpatient settings)
Based on:
Improvement of vital signs
Mentation
Ability to eat
Overall clinical condition
Follow-up[1,2,5,6]
Repeat chest imaging is not routinely recommended in those with resolution of CAP symptoms within 1 week.
If there is no improvement by day 3, or progressive worsening is seen despite receiving antibiotics, evaluate for:
Noninfectious etiologies
InfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease other than pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
Nosocomial superinfection
Lung abscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease or empyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia
ResistanceResistancePhysiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.Ventilation: Mechanics of Breathing to or wrong dose of antibiotics
Presence of unsuspected pathogens (e.g., tuberculosisTuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis, fungiFungiA kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Mycology)
Consider consultation (e.g., infectious disease, pulmonology) in cases of nonresolving pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia → may require additional testing, such as bronchoscopic sampling
CAP management checklist
Initial approach:
Confirm the diagnosis:
Clinical presentation
Imaging (chest X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests and/or chest CT)
Laboratory tests, if indicated
Determine setting of treatment using PSI (or CURB-65):
Outpatient treatment → assess comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus and discharge on recommended oral antibiotics
Inpatient treatment → continue risk evaluation and proceed with further laboratory workup as indicated
Inpatient management:
Determine the severity of pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:
ShockShockShock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock or need for vasopressorVasopressorAcute Cholangitis support and/or requiring mechanical ventilationVentilationThe total volume of gas inspired or expired per unit of time, usually measured in liters per minute.Ventilation: Mechanics of Breathing → admit to ICUICUHospital units providing continuous surveillance and care to acutely ill patients.West Nile Virus and treat as severe pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
≥ 3 of the minor criteria (confusion, tachycardiaTachycardiaAbnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.Sepsis in Children, hypothermiaHypothermiaHypothermia can be defined as a drop in the core body temperature below 35°C (95°F) and is classified into mild, moderate, severe, and profound forms based on the degree of temperature decrease. Hypothermia, hypotensionHypotensionHypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension, multilobar infiltrates, PaO2/FiO2 ≤ 250, ↓ WBC, ↓ plateletsPlateletsPlatelets are small cell fragments involved in hemostasis. Thrombopoiesis takes place primarily in the bone marrow through a series of cell differentiation and is influenced by several cytokines. Platelets are formed after fragmentation of the megakaryocyte cytoplasm. Platelets: Histology, BUN ≥ 20) → admit to ICUICUHospital units providing continuous surveillance and care to acutely ill patients.West Nile Virus and treat as severe pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
If admission does not meet criteria for severe pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia, treat as nonsevere pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia.
Determine the risk for MDR pathogens:
For severe pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:
Any risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus and/or P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas → obtain cultures (including nasal PCRPCRPolymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules.Polymerase Chain Reaction (PCR)) and add coverage for MDR pathogens to standard regimen
De-escalate, as indicated
For nonsevere pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia:
Prior respiratory isolation of MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus → obtain cultures (including nasal PCRPCRPolymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules.Polymerase Chain Reaction (PCR)) and add coverage for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus to standard regimen
Prior respiratory isolation of P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas→ obtain cultures and add coverage for P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonasto standard regimen
Recent hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium with IV antibiotics and/or validated risk factors for MRSAMRSAA strain of Staphylococcus aureus that is non-susceptible to the action of methicillin. The mechanism of resistance usually involves modification of normal or the presence of acquired penicillin binding proteins.Staphylococcus and/or P. aeruginosaP. aeruginosaA species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. Aeruginosa is a major agent of nosocomial infection.Pseudomonas→ start standard regimen and await culture results before initiating added coverage
De-escalate, as indicated
If abscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease or empyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia is suspected → add anaerobic coverage
Loculations (abscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease, empyemaEmpyemaPresence of pus in a hollow organ or body cavity.Pneumonia) which require drainage and a longer course of antibiotics
Destruction of the lungsLungsLungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy and/or fibrosisFibrosisAny pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury.Bronchiolitis Obliterans
Systemic effects of worsening CAP:
Respiratory failureRespiratory failureRespiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure
ShockShockShock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock and multiorgan failure
Coagulopathy
Exacerbation of comorbiditiesComorbiditiesThe presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.St. Louis Encephalitis Virus
Metastatic infection (rare) such as brainBrainThe part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem.Nervous System: Anatomy, Structure, and ClassificationabscessAbscessAccumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Chronic Granulomatous Disease or endocarditisEndocarditisEndocarditis is an inflammatory disease involving the inner lining (endometrium) of the heart, most commonly affecting the cardiac valves. Both infectious and noninfectious etiologies lead to vegetations on the valve leaflets. Patients may present with nonspecific symptoms such as fever and fatigue. Endocarditis
Death
Cardiovascular complications may include myocardial infarctionMyocardial infarctionMI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms.Myocardial Infarction and arrhythmias.
Nonresolving CAP:
Slow response to treatment warrants investigation of individual risk factors and a possible obstructive process (e.g., tumorTumorInflammation).
Nonresponding CAP in the initial 72 hours can be due to drug resistanceResistancePhysiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.Ventilation: Mechanics of Breathing, unusual organism or an impaired host defense.
Prevention[2,10–12]
Prevention of infectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease secondary to S. pneumoniae (pneumococcal vaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.Vaccination):
Pneumococcal conjugate vaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.Vaccination (PCV13 or 15):
For all children younger than 2 years of age
Catch-up vaccinationVaccinationVaccination is the administration of a substance to induce the immune system to develop protection against a disease. Unlike passive immunization, which involves the administration of pre-performed antibodies, active immunization constitutes the administration of a vaccine to stimulate the body to produce its own antibodies.Vaccination schedule given to those who missed shots
Pneumococcal conjugate vaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.Vaccination, options include PCV15 (which is followed by pneumococcal polysaccharide vaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.Vaccination [PPSV23]) or PCV20:
For all adults ≥ 65 years of age, or
For adults < 65 years at risk for pneumococcal infectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease
Prevention of influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza infection:
InfluenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/InfluenzavaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.Vaccination is recommended: seasonal influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/InfluenzavaccinationVaccinationVaccination is the administration of a substance to induce the immune system to develop protection against a disease. Unlike passive immunization, which involves the administration of pre-performed antibodies, active immunization constitutes the administration of a vaccine to stimulate the body to produce its own antibodies.Vaccination for all ≥ 6 months of age (who do not have contraindicationsContraindicationsA condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks).Noninvasive Ventilation)
In certain cases (e.g., vaccineVaccineSuspensions of killed or attenuated microorganisms (bacteria, viruses, fungi, protozoa), antigenic proteins, synthetic constructs, or other bio-molecular derivatives, administered for the prevention, amelioration, or treatment of infectious and other diseases.VaccinationcontraindicationsContraindicationsA condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks).Noninvasive Ventilation and high-risk for influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza complications), pre- or post-exposure prophylaxisProphylaxisCephalosporins (oseltamivirOseltamivirAn acetamido cyclohexene that is a structural homolog of sialic acid and inhibits neuraminidase.Antivirals for Influenza or zanamivirZanamivirA guanido-neuraminic acid that is used to inhibit neuraminidase.Antivirals for Influenza) is given to reduce risk of infection.
During influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/InfluenzaoutbreaksOutbreaksSudden increase in the incidence of a disease. The concept includes epidemics and pandemics.Influenza Viruses/Influenza in a hospital or a long-term care facility, empiric antiviralAntiviralAntivirals for Hepatitis B treatment is given to individuals with suspected influenzaInfluenzaInfluenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza.
Smokers should be encouraged to quit smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases.
Pulmonary edemaPulmonary edemaPulmonary edema is a condition caused by excess fluid within the lung parenchyma and alveoli as a consequence of a disease process. Based on etiology, pulmonary edema is classified as cardiogenic or noncardiogenic. Patients may present with progressive dyspnea, orthopnea, cough, or respiratory failure.Pulmonary Edema: individuals with heart failureHeart FailureA heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction.Total Anomalous Pulmonary Venous Return (TAPVR) can present with cough and dyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, especially on exertion or on lying flat. Peripheral edemaPeripheral edemaPeripheral edema is the swelling of the lower extremities, namely, legs, feet, and ankles.Edema can be noted, along with S3S3Heart Sounds heart sound and elevated jugular venous pressureJugular Venous PressurePortal Hypertension. Elevated B-type natriuretic peptide (BNPBNPA peptide that is secreted by the brain and the heart atria, stored mainly in cardiac ventricular myocardium. It can cause natriuresis; diuresis; vasodilation; and inhibits secretion of renin and aldosterone. It improves heart function. It contains 32 amino acids.Renal Sodium and Water Regulation) and N-terminal pro-BNP (NT-proBNP) is noted. Transthoracic echocardiogramTransthoracic echocardiogramEndocarditis generally reveals a reduced ejection fractionEjection fractionCardiac Cycle and systolic (and/or diastolic) dysfunction.
Pulmonary embolismPulmonary EmbolismPulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism: rarely presents with productive cough or infiltrations visible on chest X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests, but signs can include tachypneaTachypneaIncreased respiratory rate.Pulmonary Examination and tachycardiaTachycardiaAbnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.Sepsis in Children. Examination may also reveal a unilateral legLegThe lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia.Leg: AnatomyswellingSwellingInflammation. Pulmonary CT angiographyAngiographyRadiography of blood vessels after injection of a contrast medium.Cardiac Surgery confirms the diagnosis.
Lung carcinoma: a history of smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases, constitutional symptomsConstitutional SymptomsAntineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis (e.g., significant weight lossWeight lossDecrease in existing body weight.Bariatric Surgery), or chronic cough may be suggestive of lung cancerLung cancerLung cancer is the malignant transformation of lung tissue and the leading cause of cancer-related deaths. The majority of cases are associated with long-term smoking. The disease is generally classified histologically as either small cell lung cancer or non-small cell lung cancer. Symptoms include cough, dyspnea, weight loss, and chest discomfort. Lung Cancer. Chest CT, with a subsequent follow-up (after resolution of pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia), is recommended to differentiate consolidationConsolidationPulmonary Function Tests/infiltrates from a tumorTumorInflammation.
Interstitial lung disease: cough and shortness of breathShortness of breathDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary).Dyspnea can be manifestations of lung parenchymal conditions including hypersensitivity pneumonitisPneumonitisHuman Herpesvirus 6 and 7, asbestosisAsbestosisA form of pneumoconiosis caused by inhalation of asbestos fibers which elicit potent inflammatory responses in the parenchyma of the lung. The disease is characterized by interstitial fibrosis of the lung, varying from scattered sites to extensive scarring of the alveolar interstitium.Pneumoconiosis, systemic manifestations of rheumatologic diseases (systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected.Systemic Lupus Erythematosus, rheumatoid arthritisArthritisAcute or chronic inflammation of joints.Osteoarthritis among others). Historical details, additional lab work-up and chest CT help distinguish other underlying chronic lung diseases from an acute pneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia.
Infectious differential diagnoses
Acute bronchitisAcute BronchitisAcute bronchitis is an infection of the mucous membrane of the bronchi without evidence of pneumonia. Due to its pathogenesis, acute bronchitis is frequently accompanied by an upper respiratory tract infection. Cases in which the trachea is also involved are referred to as tracheobronchitis. Acute Bronchitis: infection involving the bronchiBronchiThe larger air passages of the lungs arising from the terminal bifurcation of the trachea. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into bronchioles and pulmonary alveoli.Bronchial Tree: Anatomy, and not the lung parenchyma. Generally, this condition is not associated with abnormal vital signs and/or systemic signs of infection.
Acute exacerbation of COPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD) (AECOPD): characterized by acute worsening of COPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD) symptoms, which include dyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea, increased coughing and sputum production. InfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease can triggerTriggerThe type of signal that initiates the inspiratory phase by the ventilatorInvasive Mechanical VentilationCOPDCOPDChronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD) exacerbation.
TuberculosisTuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis: pulmonary tuberculosisTuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis is caused by Mycobacterium tuberculosisMycobacterium tuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes.Tuberculosis, and manifests as cough and dyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea. Weight lossWeight lossDecrease in existing body weight.Bariatric Surgery is a common feature. Different factors (travel history, residents of an endemic area, immunocompromisedimmunocompromisedA human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.Gastroenteritis state, work in high-risk settings) help assess risk of developing pulmonary tuberculosisTuberculosisTuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis. Diagnosis requires sputum acid-fast bacilliAcid-fast bacilliMycobacterium (AFBAFBMycobacterium), mycobacterial culture and molecular testing.
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