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Metal Poisoning (Lead, Arsenic, Iron)

Heavy metals poisoning is the toxic accumulation of metals in the body, which can occur due to ingestion or inhalation. These elements are normally found in nature and can have many applications (e.g., agriculture, medicine, industry); however, toxicity Toxicity Dosage Calculation is rare. Common metals that the human body absorbs in toxic amounts are lead, arsenic, and iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements. Presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor is variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables and management involves the use of chelating agents.

Last updated: 11 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Lead Poisoning

Etiology

Lead poisoning, also known as plumbism, may result from inhalation or ingestion of lead from:

  • Lead paint
  • Food and drinks in lead-soldered cans
  • Contaminated tap water
  • Lead bullets
  • Occupational exposure Exposure ABCDE Assessment (e.g., batteries, ammunition, construction, renovation, alcohol distillation with lead soldering)

Pathophysiology

  • Hematologic effects:
    • Contributes to RBC membrane fragility → hemolysis
    • Inhibits ferrochelatase Ferrochelatase A mitochondrial enzyme found in a wide variety of cells and tissues. It is the final enzyme in the 8-enzyme biosynthetic pathway of heme. Ferrochelatase catalyzes ferrous insertion into protoporphyrin IX to form protoheme or heme. Heme Metabolism and aminolevulinic acid Aminolevulinic acid A compound produced from succinyl-CoA and glycine as an intermediate in heme synthesis. It is used as a photochemotherapy for actinic keratosis. Heme Metabolism dehydratase ( enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes in the heme synthesis Synthesis Polymerase Chain Reaction (PCR) pathway) → ↓ hemoglobin synthesis Synthesis Polymerase Chain Reaction (PCR)
    • Inhibits ribosomal RNA Ribosomal RNA The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. RNA Types and Structure degradation → RBCs RBCs Erythrocytes, 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 retain aggregates of rRNA rRNA The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. RNA Types and Structure → basophilic stippling
  • Neurologic effects:
    • Lead displaces calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes ions → ↑ blood- brain Brain The 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 Classification barrier permeability → allows lead to cross and contributes to cerebral edema Cerebral edema Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries. An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive hydrocephalus). Increased Intracranial Pressure (ICP)
    • Accumulation in astroglial cells and prevents myelin sheath formation → demyelination Demyelination Multiple Sclerosis

Clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor

Children:

  • Poor appetite
  • Nausea Nausea An 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 vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia
  • Lead lines on gingival border (Burton lines) 
  • Headaches
  • Encephalopathy Encephalopathy Hyper-IgM Syndrome
    • Somnolence
    • Coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma
    • Seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures
  • Developmental delay
  • Behavioral changes

Adults:

  • Nonspecific symptoms:
    • Fatigue Fatigue The 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
    • Insomnia Insomnia Insomnia is a sleep disorder characterized by difficulty in the initiation, maintenance, and consolidation of sleep, leading to impairment of function. Patients may exhibit symptoms such as difficulty falling asleep, disrupted sleep, trouble going back to sleep, early awakenings, and feeling tired upon waking. Insomnia
    • Arthralgia Arthralgia Pain in the joint. Rheumatic Fever and myalgia Myalgia Painful sensation in the muscles. Ion Channel Myopathy
  • Gl symptoms: 
    • Abdominal pain Abdominal Pain Acute Abdomen
    • Constipation Constipation Constipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation
    • Anorexia Anorexia The lack or loss of appetite accompanied by an aversion to food and the inability to eat. It is the defining characteristic of the disorder anorexia nervosa. Anorexia Nervosa
  • Neurological manifestations:
  • Chronic exposure Exposure ABCDE Assessment leads to: 
    • Nephropathy
    • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension 
    • ↑ Risk of cardiovascular mortality Mortality All deaths reported in a given population. Measures of Health Status
Lead line in gingiva - metal poisoning

Clinical findings associated with lead poisoning:
a. lead line along the gingival border (Burton lines)
b. wrist drop as a consequence of peripheral neuropathy

Image: “ Radial neuropathy Radial neuropathy Disease involving the radial nerve. Clinical features include weakness of elbow extension, elbow flexion, supination of the forearm, wrist and finger extension, and thumb abduction. Sensation may be impaired over regions of the dorsal forearm. Common sites of compression or traumatic injury include the axilla and radial groove of the humerus. Mononeuropathy and Plexopathy due to occupational lead exposure Exposure ABCDE Assessment” by Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), India. License: CC BY 2.0

Diagnosis

  • In children, dense metaphyseal lines can be seen on X-ray X-ray Penetrating 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 (lead concentrates in metaphyses of growing bones):
    • Distal femur
    • Both ends of tibia Tibia The second longest bone of the skeleton. It is located on the medial side of the lower leg, articulating with the fibula laterally, the talus distally, and the femur proximally. Knee Joint: Anatomy
    • Distal radius Radius The outer shorter of the two bones of the forearm, lying parallel to the ulna and partially revolving around it. Forearm: Anatomy 
  • Initial screening Screening Preoperative Care test: capillary (fingerstick) lead measurement
  • Confirmatory test: venous lead measurement
  • Other findings:
    • Normocytic or microcytic anemia Microcytic anemia Conditions in which there is a generalized increase in the iron stores of body tissues, particularly of liver and the mononuclear phagocyte system, without demonstrable tissue damage. The name refers to the presence of stainable iron in the tissue in the form of hemosiderin. Anemia: Overview and Types
    • Erythrocyte basophilic stippling on peripheral smear
    • ↑ Serum zinc Zinc A metallic element of atomic number 30 and atomic weight 65. 38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with anemia, short stature, hypogonadism, impaired wound healing, and geophagia. It is known by the symbol zn. Trace Elements protoporphyrin level
Giemsa stain of coarse basophilic stippling or erythrocytes due to lead poisoning

Wright-Giemsa–stained smear of peripheral blood: coarse basophilic stippling of the erythrocytes

Image: “Wright-Giemsa stained smear” by Yale Cancer Center, Section of Hematology, Yale University School of Medicine, New Haven, CT 06511, USA. License: CC BY 2.0

Management

Arsenic Poisoning

Etiology

  • Herbicides (vineyard workers)
  • Insecticides Insecticides Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics. Trypanosoma cruzi/Chagas disease 
  • Metal smelting
  • Contaminated water (often from wells) 
  • Pressure-treated wood

Pathophysiology

  • Arsenic causes glycolysis Glycolysis Glycolysis is a central metabolic pathway responsible for the breakdown of glucose and plays a vital role in generating free energy for the cell and metabolites for further oxidative degradation. Glucose primarily becomes available in the blood as a result of glycogen breakdown or from its synthesis from noncarbohydrate precursors (gluconeogenesis) and is imported into cells by specific transport proteins. Glycolysis to produce zero net ATP.
  • Arsenic inhibits lipoic acid (part of pyruvate Pyruvate Derivatives of pyruvic acid, including its salts and esters. Glycolysis dehydrogenase complex).
  • Binds to sulfhydryl groups 
  • Disrupts cellular respiration Respiration The act of breathing with the lungs, consisting of inhalation, or the taking into the lungs of the ambient air, and of exhalation, or the expelling of the modified air which contains more carbon dioxide than the air taken in. Nose and Nasal Cavity: Anatomy and gluconeogenesis Gluconeogenesis Gluconeogenesis is the process of making glucose from noncarbohydrate precursors. This metabolic pathway is more than just a reversal of glycolysis. Gluconeogenesis provides the body with glucose not obtained from food, such as during a fasting period. The production of glucose is critical for organs and cells that cannot use fat for fuel. Gluconeogenesis

Clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor

Acute:

  • General:
  • GI:
  • Cardiopulmonary:
    • Hypotension Hypotension Hypotension 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
    • QT prolongation
    • Cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) arrhythmias
    • Shock Shock Shock 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
    • ARDS ARDS Acute respiratory distress syndrome is characterized by the sudden onset of hypoxemia and bilateral pulmonary edema without cardiac failure. Sepsis is the most common cause of ARDS. The underlying mechanism and histologic correlate is diffuse alveolar damage (DAD). Acute Respiratory Distress Syndrome (ARDS)
  • Acute encephalopathy:
    • Delirium Delirium Delirium is a medical condition characterized by acute disturbances in attention and awareness. Symptoms may fluctuate during the course of a day and involve memory deficits and disorientation. Delirium
    • Coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma
    • Seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures
  • Renal:
    • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children
    • Acute renal failure Renal failure Conditions in which the kidneys perform below the normal level in the ability to remove wastes, concentrate urine, and maintain electrolyte balance; blood pressure; and calcium metabolism. Renal insufficiency can be classified by the degree of kidney damage (as measured by the level of proteinuria) and reduction in glomerular filtration rate. Crush Syndrome

Chronic:

  • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions manifestations: 
    • Mees lines on fingernails (transverse white bands)
    • Pigmentation (hypo or hyper) 
    • Hyperkeratosis Hyperkeratosis Ichthyosis Vulgaris
    • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions cancer ( squamous cell carcinoma Squamous cell carcinoma Cutaneous squamous cell carcinoma (cSCC) is caused by malignant proliferation of atypical keratinocytes. This condition is the 2nd most common skin malignancy and usually affects sun-exposed areas of fair-skinned patients. The cancer presents as a firm, erythematous, keratotic plaque or papule. Squamous Cell Carcinoma (SCC))
  • Stocking-glove neuropathy:
  • Liver cancer (angiosarcoma) 
  • Lung cancer Lung cancer Lung 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
  • Pancytopenia Pancytopenia Deficiency of all three cell elements of the blood, erythrocytes, leukocytes and platelets. Aplastic Anemia

Diagnosis

  • Suspected through history and physical examination
  • Hemolytic anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types may be seen.
  • Urine arsenic level 
  • Plasma Plasma The residual portion of blood that is left after removal of blood cells by centrifugation without prior blood coagulation. Transfusion Products arsenic concentrations (helpful, but rarely available until after the decision to treat is made)

Management

  • Decontamination of the skin and GI tract
  • Supportive care
  • Chelation therapy in symptomatic patients only:
    • Dimercaprol (1st line)
    • Succimer (dimercaptosuccinic acid (DMSA))
    • Unithiol Unithiol A chelating agent used as an antidote to heavy metal poisoning. Antidotes of Common Poisonings (2,3-Dimercapto-1-propanesulfonic acid (DMPS))
  • Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome in severe cases

Iron Poisoning

Etiology

  • Accidental ingestion by children ( iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements tablets may look like candy) 
  • Can be chronic in patients requiring multiple transfusions of RBCs RBCs Erythrocytes, 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

Epidemiology

Iron toxicity Toxicity Dosage Calculation is one of the leading causes of deaths by poisoning in children < 6 years.

Pathophysiology

Absorption Absorption Absorption involves the uptake of nutrient molecules and their transfer from the lumen of the GI tract across the enterocytes and into the interstitial space, where they can be taken up in the venous or lymphatic circulation. Digestion and Absorption of excessive quantities of ingested iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements can lead to:

  • Cellular toxicity Toxicity Dosage Calculation:
    • Impaired oxidative phosphorylation Impaired Oxidative Phosphorylation Cell Injury and Death and mitochondrial dysfunction → cellular death
    • The liver Liver The 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 is the most affected organ.
    • In chronic overload, iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements deposits into myocardial cells → myocardial siderosis and death
  • Corrosive toxicity Toxicity Dosage Calculation:
    • Iron is corrosive to GI mucosa.
    • Leads to GI symptoms and potential blood loss

Clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor

  • Stage 1 Stage 1 Trypanosoma brucei/African trypanosomiasis: GI
    • < 6 hours after ingestion
    • Nausea Nausea An 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
    • Diarrhea
    • Abdominal pain Abdominal Pain Acute Abdomen
    • Hemorrhagic gastroenteritis Gastroenteritis Gastroenteritis is inflammation of the stomach and intestines, commonly caused by infections from bacteria, viruses, or parasites. Transmission may be foodborne, fecal-oral, or through animal contact. Common clinical features include abdominal pain, diarrhea, vomiting, fever, and dehydration. Gastroenteritis:
    • Capillary leak/3rd spacing → hypovolemia Hypovolemia Sepsis in Children or shock
  • Stage 2: latent
    • 6–24 hours after ingestion
    • GI symptoms resolve → patient seems to improve and recover
    • Some patients may demonstrate: 
      • Hypotension Hypotension Hypotension 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
      • Metabolic acidosis Metabolic acidosis The renal system is responsible for eliminating the daily load of non-volatile acids, which is approximately 70 millimoles per day. Metabolic acidosis occurs when there is an increase in the levels of new non-volatile acids (e.g., lactic acid), renal loss of HCO3-, or ingestion of toxic alcohols. Metabolic Acidosis
      • Oliguria Oliguria Decreased urine output that is below the normal range. Oliguria can be defined as urine output of less than or equal to 0. 5 or 1 ml/kg/hr depending on the age. Renal Potassium Regulation
  • Stage 3: metabolic/cardiovascular
    • 6–72 hours after ingestion
    • Metabolic acidosis Metabolic acidosis The renal system is responsible for eliminating the daily load of non-volatile acids, which is approximately 70 millimoles per day. Metabolic acidosis occurs when there is an increase in the levels of new non-volatile acids (e.g., lactic acid), renal loss of HCO3-, or ingestion of toxic alcohols. Metabolic Acidosis
    • Cardiovascular symptoms
      • Tachycardia Tachycardia Abnormally 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
      • Hypotension Hypotension Hypotension 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
      • Pallor
      • Shock Shock Shock 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
    • Central nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). It is divided according to its anatomical components as well as its functional characteristics. The brain and spinal cord are referred to as the central nervous system, and the branches of nerves from these structures are referred to as the peripheral nervous system. Nervous System: Anatomy, Structure, and Classification symptoms:
      • Stupor
      • Coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma
    • GI hemorrhage
    • Acute lung injury or ARDS ARDS Acute respiratory distress syndrome is characterized by the sudden onset of hypoxemia and bilateral pulmonary edema without cardiac failure. Sepsis is the most common cause of ARDS. The underlying mechanism and histologic correlate is diffuse alveolar damage (DAD). Acute Respiratory Distress Syndrome (ARDS)
    • Coagulopathy
    • Renal dysfunction
    • Most deaths occur in this stage.
  • Stage 4: hepatic
    • 12–96  hours after ingestion
    • ↑ Liver enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes and bilirubin Bilirubin A bile pigment that is a degradation product of heme. Heme Metabolism levels 
    • Coagulopathy
    • Hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia may accompany liver Liver The 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 dysfunction.
  • Stage 5: delayed

Diagnosis

  • Suspected by history and physical examination 
  • Serum iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements levels will confirm the diagnosis.
  • Supporting studies: 
    • Anion gap Anion gap Metabolic Acidosis metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis
    • Check liver Liver The 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 function, CBC, coagulation factors Coagulation factors Endogenous substances, usually proteins, that are involved in the blood coagulation process. Hemostasis, glucose Glucose A 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, and renal function tests.
  • Abdominal imaging may show radiopaque Radiopaque An object of high density that blocks X-rays (looks white) X-rays tablets in the stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy.

Management

  • Stabilize the patient.
  • IV fluids IV fluids Intravenous fluids are one of the most common interventions administered in medicine to approximate physiologic bodily fluids. Intravenous fluids are divided into 2 categories: crystalloid and colloid solutions. Intravenous fluids have a wide variety of indications, including intravascular volume expansion, electrolyte manipulation, and maintenance fluids. Intravenous Fluids
  • Orogastric lavage and/or whole-bowel irrigation is indicated in patients with a significant number of radiopaque Radiopaque An object of high density that blocks X-rays (looks white) X-rays pills in the stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy on imaging.
  • Chelation therapy (IV deferoxamine Deferoxamine Natural product isolated from streptomyces pilosus. It forms iron complexes and is used as a chelating agent, particularly in the mesylate form. Hereditary Hemochromatosis, oral deferasirox Deferasirox A triazole and benzoate derivative that acts as a selective iron chelator. It is used in the management of chronic iron overload due to blood transfusion or non-transfusion dependent thalassemia. Hereditary Hemochromatosis) is indicated if any of the following is present: 
    • Severe symptoms ( altered mental status Altered Mental Status Sepsis in Children, hemodynamic instability, persistent vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and/or diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
    • Anion gap Anion gap Metabolic Acidosis metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis 
    • Serum iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements concentration > 500 μ/dL  
    • Significant number of pills on abdominal X-ray X-ray Penetrating 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
  • Dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis (exchange transfusion or continuous veno-venous hemofiltration) is indicated if chelation therapy fails to improve patient symptoms.

Differential Diagnosis

  • Sideroblastic anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types: microcytic anemia Microcytic anemia Conditions in which there is a generalized increase in the iron stores of body tissues, particularly of liver and the mononuclear phagocyte system, without demonstrable tissue damage. The name refers to the presence of stainable iron in the tissue in the form of hemosiderin. Anemia: Overview and Types in which the bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types marrow produces sideroblasts (ring-shaped RBCs RBCs Erythrocytes, 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) instead of normal, round-shaped RBCs RBCs Erythrocytes, 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 due to the inability of the body to place iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements properly into hemoglobin. Lead poisoning inhibits the conversion of protoporphyrins Protoporphyrins Porphyrins with four methyl, two vinyl, and two propionic acid side chains attached to the pyrrole rings. Protoporphyrin IX occurs in hemoglobin, myoglobin, and most of the cytochromes. Heme Metabolism necessary for heme synthesis Synthesis Polymerase Chain Reaction (PCR), resulting in sideroblastic anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types.
  • Esophagitis Esophagitis Esophagitis is the inflammation or irritation of the esophagus. The major types of esophagitis are medication-induced, infectious, eosinophilic, corrosive, and acid reflux. Patients typically present with odynophagia, dysphagia, and retrosternal chest pain. Esophagitis: inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation or irritation of the esophagus Esophagus The esophagus is a muscular tube-shaped organ of around 25 centimeters in length that connects the pharynx to the stomach. The organ extends from approximately the 6th cervical vertebra to the 11th thoracic vertebra and can be divided grossly into 3 parts: the cervical part, the thoracic part, and the abdominal part. Esophagus: Anatomy. The major types of esophagitis are medication induced, infectious Infectious Febrile Infant, eosinophilic, corrosive, and acid reflux. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship typically present with odynophagia Odynophagia Epiglottitis, dysphagia Dysphagia Dysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical. Dysphagia, and retrosternal chest pain Chest Pain Chest pain is one of the most common and challenging complaints that may present in an inpatient and outpatient setting. The differential diagnosis of chest pain is large and includes cardiac, gastrointestinal, pulmonary, musculoskeletal, and psychiatric etiologies. Chest Pain. Diagnosis is by endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD) and biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Management depends on the etiology but includes medications and possible surgery.
  • Herbicides: substances used to control the growth of unwanted plants Plants Cell Types: Eukaryotic versus Prokaryotic and in the construction industry. Different types of herbicides result in different clinical manifestations. Early management and treatment are important to prevent further intoxication.
  • Pesticides: chemical substances used to control pests, including weeds. Important types include organochlorines ( dichlorodiphenyltrichloroethane Dichlorodiphenyltrichloroethane A polychlorinated pesticide that is resistant to destruction by light and oxidation. Its unusual stability has resulted in difficulties in residue removal from water, soil, and foodstuffs. This substance may reasonably be anticipated to be a carcinogen: fourth annual report on carcinogens. Insecticide Poisoning ( DDT DDT A polychlorinated pesticide that is resistant to destruction by light and oxidation. Its unusual stability has resulted in difficulties in residue removal from water, soil, and foodstuffs. This substance may reasonably be anticipated to be a carcinogen: fourth annual report on carcinogens. Insecticide Poisoning)) and organophosphates ( malathion Malathion A wide spectrum aliphatic organophosphate insecticide widely used for both domestic and commercial agricultural purposes. Cholinomimetic Drugs and parathion Parathion A highly toxic cholinesterase inhibitor that is used as an acaricide and as an insecticide. Insecticide Poisoning). Different types of pesticides result in different clinical manifestations. Early management and treatment are important to prevent further intoxication.

References

  1. Blumenberg, A. (2019). Arsenic Toxicity Clinical Presentation. Emedicine. Retrieved March 14, 2021, from https://emedicine.medscape.com/article/812953-clinical
  2. Buggs, A. (2021). Emergent Management of Lead Toxicity. Emedicine. Retrieved March 15, 2021, from https://emedicine.medscape.com/article/815399-overview#a4
  3. Spanierman, C. (2020). Iron Toxicity. Emedicine. Retrieved March 14, 2021, from https://emedicine.medscape.com/article/815213-overview
  4. Sample, J. (2020). Childhood lead poisoning: Clinical manifestations and diagnosis. UpToDate. Retrieved March 14, 2021, from https://www.uptodate.com/contents/childhood-lead-poisoning-clinical-manifestations-and-diagnosis
  5. Goldman, R. and Hu, H. (2020). Lead exposure and poisoning in adults. UpToDate. Retrieved March 14, 2021, from https://www.uptodate.com/contents/adult-occupational-lead-poisoning
  6. Golfman, R. (2020). Arsenic exposure and poisoning. UpToDate. Retrieved March 13, 2021, from https://www.uptodate.com/contents/arsenic-exposure-and-poisoning
  7. Liebelt, E. (2020). Acute iron poisoning. UpToDate. Retrieved March 13, 2021, from https://www.uptodate.com/contents/acute-iron-poisoning

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