Gastritis (Clinical)

Overview

Definition

Gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis is the 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 of gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy associated with mucosal injury.

Gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis refers to a disease of 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 associated with reactive or hyperplastic Hyperplastic Colon Polyps epithelial changes with only minimal or no 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, but the term “ gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis” is commonly used to encompass these conditions as well

Etiology^[10]

Gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis is usually due to an infection or an immune-mediated process, but it can also be caused by substances that are direct gastric irritants. Numerous infectious and noninfectious diseases can cause gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis.

• Infectious: 
  • Helicobacter pylori Helicobacter pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter:
    • Most common
    • Route of transmission is unclear, but person-to-person transmission most likely.
  • Rare infectious causes:
    • Mycobacterium Mycobacterium Mycobacterium is a genus of the family Mycobacteriaceae in the phylum Actinobacteria. Mycobacteria comprise more than 150 species of facultative intracellular bacilli that are mostly obligate aerobes. Mycobacteria are responsible for multiple human infections including serious diseases, such as tuberculosis (M. tuberculosis), leprosy (M. leprae), and M. avium complex infections. Mycobacterium avium-intracellulare
    • Enterococcus Enterococcus Enterococcus is a genus of oval-shaped gram-positive cocci that are arranged in pairs or short chains. Distinguishing factors include optochin resistance and the presence of pyrrolidonyl arylamidase (PYR) and Lancefield D antigen. Enterococcus is part of the normal flora of the human GI tract. Enterococcus
    • Herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections viruses Viruses Minute 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
    • Cytomegalovirus Cytomegalovirus CMV is a ubiquitous double-stranded DNA virus belonging to the Herpesviridae family. CMV infections can be transmitted in bodily fluids, such as blood, saliva, urine, semen, and breast milk. The initial infection is usually asymptomatic in the immunocompetent host, or it can present with symptoms of mononucleosis. Cytomegalovirus
    • Parasites
• Autoimmune (associated with anti-parietal and anti-intrinsic factor antibodies Antibodies Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution. Immunoglobulins: Types and Functions, which may progress to pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia)
• Chemical/reactive gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis (technically gastropathies because they cause mucosal injury without significant 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):
  • Medication-induced gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis:
    • NSAIDs NSAIDS Primary vs Secondary Headaches and aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs), even low dose
    • Chemotherapy Chemotherapy Osteosarcoma
    • Bisphosphonates Bisphosphonates Bisphosphonates are pyrophosphate analogs most well-known for treating osteoporosis by preventing bone loss. Bisphosphonates end in the suffix “-dronate” or “-dronic acid” (e.g., alendronate, risedronate, pamidronate) and bind to hydroxyapatite crystals in bone, inhibiting osteoclast-induced bone resorption. Bisphosphonates (e.g., alendronate Alendronate A nonhormonal medication for the treatment of postmenopausal osteoporosis in women. This drug builds healthy bone, restoring some of the bone loss as a result of osteoporosis. Bisphosphonates)
  • Gastric irritants
    • Alcohol
    • Caffeine Caffeine A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine’s most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide phosphodiesterases, antagonism of adenosine receptors, and modulation of intracellular calcium handling. Stimulants
    • Spicy foods
    • Tobacco
  • Bile Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile acids and salts; cholesterol; and electrolytes. It aids digestion of fats in the duodenum. Gallbladder and Biliary Tract: Anatomy reflux after gastrectomy (postgastrectomy gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis)
• Uncommon causes:
  • Granulomatous diseases Granulomatous diseases A defect of leukocyte function in which phagocytic cells ingest but fail to digest bacteria, resulting in recurring bacterial infections with granuloma formation. When chronic granulomatous disease is caused by mutations in the cybb gene, the condition is inherited in an X-linked recessive pattern. When chronic granulomatous disease is caused by cyba, ncf1, ncf2, or ncf4 gene mutations, the condition is inherited in an autosomal recessive pattern. Type IV Hypersensitivity Reaction:
    • Crohn disease
    • Sarcoidosis Sarcoidosis Sarcoidosis is a multisystem inflammatory disease that causes noncaseating granulomas. The exact etiology is unknown. Sarcoidosis usually affects the lungs and thoracic lymph nodes, but it can also affect almost every system in the body, including the skin, heart, and eyes, most commonly. Sarcoidosis
  • Radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma
  • Vasculitis Vasculitis Inflammation of any one of the blood vessels, including the arteries; veins; and rest of the vasculature system in the body. Systemic Lupus Erythematosus
  • Collagenous gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis
  • Eosinophilic gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis
  • Ischemic gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis:
    • Burns Burns A burn is a type of injury to the skin and deeper tissues caused by exposure to heat, electricity, chemicals, friction, or radiation. Burns are classified according to their depth as superficial (1st-degree), partial-thickness (2nd-degree), full-thickness (3rd-degree), and 4th-degree burns. Burns
    • Trauma
    • Sepsis Sepsis Systemic 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

Classification^[8,10,12]

There are multiple ways to classify gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis:

• By etiology/pathogenesis
• By time course:
  • Acute 
  • Chronic (much more common; often subdivided based on etiology):
    • Autoimmune metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (AMAG)
    • Environmental metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (EMAG)
• By severity of mucosal injury:
  • Erosive 
  • Nonerosive
• By histology, based on the inflammatory cell type and duration:
  • Acute gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis: polymorphonuclear leukocyte infiltration of the gastric antrum and body.
    • Rare to have only neutrophils Neutrophils Granular 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 present
    • Neutrophils Neutrophils Granular 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 are much more commonly seen in “chronic active gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis,” where both neutrophils Neutrophils Granular 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 are present along with chronic inflammatory cells.
  • Chronic gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis (much more common than pure acute gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis) → 3 types:
    • Diffuse antral gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis: usually due to H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter infection, showing chronic inflammatory cells in the lamina propria Lamina propria Whipple’s Disease and neutrophils Neutrophils Granular 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 infiltrating the gastric pit epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology.
    • Environmental metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (EMAG, also called “ multifocal Multifocal Retinoblastoma atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis”), typified by involvement of both the gastric antrum and corpus with glandular atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation and intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation (IM)
    • Autoimmune metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (AMAG, “corpus-predominant AG AG Metabolic Acidosis”): an autoimmune destruction of glands, characterized by atrophic glands with extensive IM and nests of enterochromaffin-like cells Enterochromaffin-like cells Neuroendocrine cells in the glands of the gastric mucosa. They produce histamine and peptides such as chromogranins. Ecl cells respond to gastrin by releasing histamine which acts as a paracrine stimulator of the release of hydrochloric acid from the gastric parietal cells. Gastrointestinal Secretions, confined to the corpus mucosa
    • Note: Atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis has an annual incidence Incidence The 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 of progression to gastric cancer Gastric cancer Gastric cancer is the 3rd-most common cause of cancer-related deaths worldwide. The majority of cases are from adenocarcinoma. The modifiable risk factors include Helicobacter pylori infection, smoking, and nitrate-rich diets. Gastric Cancer of approximately 0.1% to 1.0%, with EMAG > AMAG.

There is no universal classification or grading Grading Methods which attempt to express in replicable terms the level of cell differentiation in neoplasms as increasing anaplasia correlates with the aggressiveness of the neoplasm. Grading, Staging, and Metastasis system, but 2 common systems are listed below, for reference only:

Updated Sydney system:^[12] 

• Requires 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 biopsies from the antrum, corpus, and incisura angularis
• Classifies gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis based on:
  • Topography (where it occurs 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) → provides the “core” for the classification:
    • Antrum ( H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter typically starts in the antrum.)
    • Corpus (AMAG typically starts in the corpus.)
    • Pangastritis (throughout the entire 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)
  • Likely etiology → provides the “prefix”; examples:
    • Infectious (specific agent should be noted)
    • Autoimmune
    • Environmental
    • Other gastropathies: chemical/reactive gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis from bile Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile acids and salts; cholesterol; and electrolytes. It aids digestion of fats in the duodenum. Gallbladder and Biliary Tract: Anatomy reflux or NSAIDs NSAIDS Primary vs Secondary Headaches, radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma injury, granulomatous disease Granulomatous disease A defect of leukocyte function in which phagocytic cells ingest but fail to digest bacteria, resulting in recurring bacterial infections with granuloma formation. When chronic granulomatous disease is caused by mutations in the cybb gene, the condition is inherited in an X-linked recessive pattern. When chronic granulomatous disease is caused by cyba, ncf1, ncf2, or ncf4 gene mutations, the condition is inherited in an autosomal recessive pattern. Common Variable Immunodeficiency (CVID), etc ETC The electron transport chain (ETC) sends electrons through a series of proteins, which generate an electrochemical proton gradient that produces energy in the form of adenosine triphosphate (ATP). Electron Transport Chain (ETC).
  • Morphology → provides possible “suffixes”; the system defines 5 specific morphologic variables that are graded from none → mild → moderate → severe/marked:
    • Chronic inflammation Chronic Inflammation Inflammation (based on presence of lymphocytes Lymphocytes Lymphocytes are heterogeneous WBCs involved in immune response. Lymphocytes develop from the bone marrow, starting from hematopoietic stem cells (HSCs) and progressing to common lymphoid progenitors (CLPs). B and T lymphocytes and natural killer (NK) cells arise from the lineage. Lymphocytes: Histology and plasma Plasma The residual portion of blood that is left after removal of blood cells by centrifugation without prior blood coagulation. Transfusion Products cells)
    • Activity (based on presence of neutrophils Neutrophils Granular 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)
    • Intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation
    • Atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation (based on loss of normal mucosal glands)
    • Presence of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter 
• Examples:
  • H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter antral gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis, moderately active with mild antral atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation
  • Autoimmune corpus gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis with severe intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation and atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation
  • Reactive mild pangastritis without H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter

Operative link for gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis assessment (OLGA):^[10]

• Helps stage chronic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis and predict cancer risk 
• Example from one study:[15]
  • Stage 0: 0.03 cancer cases/10³ person-years
  • Stage I: 0.34 cases/10³ person-years
  • Stage II: 1.5 cases/10³ person-years
  • Stage III: 19 cases/10³ person-years
  • Stage IV: 41 cases/10³ person-years
• Based on severity of atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation in both the antrum and the corpus/body of 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

Epidemiology^{[1,2,11,13,16]}

H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter infection: affects more than half the worldwide population, or 4.4 billion people

• Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency ranges from 19% in Switzerland to 88% in Nigeria
• Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency in the US is higher in certain groups:
  • Hispanics (60%)
  • African Americans (54%)
  • Adults over age 60 (50%)
• H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter infection is associated with:
  • 60% of gastric ulcers
  • 80% of duodenal ulcers
  • Environmental metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (EMAG) in 85% of cases
• Most individuals with H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter never develop disease.
• H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency in the pediatric population is a major determinant of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis.

Autoimmune metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (AMAG, i.e., the pathologic process underlying pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia):

• Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency: 2% in Western countries
• Risk increases with age
• Women > men

Pathophysiology

H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter–associated gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis^[8,10,13]

• Can be acute or chronic
• H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter resides in the gastric mucus adjacent to epithelial cells and invades the lamina propria Lamina propria Whipple’s Disease.
• Acute (early stage):
  • Antral-predominant 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 gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis
  • ↑ Gastrin Gastrin A family of gastrointestinal peptide hormones that excite the secretion of gastric juice. They may also occur in the central nervous system where they are presumed to be neurotransmitters. Gastrointestinal Secretions + ↓ somatostatin Somatostatin A 14-amino acid peptide named for its ability to inhibit pituitary growth hormone release, also called somatotropin release-inhibiting factor. It is expressed in the central and peripheral nervous systems, the gut, and other organs. SRIF can also inhibit the release of thyroid-stimulating hormone; prolactin; insulin; and glucagon besides acting as a neurotransmitter and neuromodulator. In a number of species including humans, there is an additional form of somatostatin, srif-28 with a 14-amino acid extension at the n-terminal. Gastrointestinal Secretions = ↑ acid production
  • Increased acid exacerbates mucosal injury and 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.
  • Due to antral location, duodenal ulcer Duodenal ulcer A peptic ulcer located in the duodenum. Peptic Ulcer Disease is a possible complication.
• Progression from early-stage chronic gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis to atrophic (later-stage) gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis is a slow process as gastric glands Gastric glands Stomach: Anatomy disappear.
• Chronic (late stage):
  • Environmental metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (EMAG)
  • Ongoing 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 of gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy results in loss of G cells (gastrin-producing) and parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy (acid-producing).
  • This change allows proximal migration of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter → spread from the antrum to the gastric body
  • Effects:
    • Atrophic glands → intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation of gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy (increased risk of gastric cancer Gastric cancer Gastric cancer is the 3rd-most common cause of cancer-related deaths worldwide. The majority of cases are from adenocarcinoma. The modifiable risk factors include Helicobacter pylori infection, smoking, and nitrate-rich diets. Gastric Cancer)
    • Loss of acid production → hypochlorhydria → reduced iron absorption Iron absorption Digestion and Absorption
    • Loss of parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy → ↓ intrinsic factor Intrinsic factor A glycoprotein secreted by the cells of the gastric glands that is required for the absorption of vitamin B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to vitamin B12 deficiency and anemia, pernicious. Gastritis → B₁₂ deficiency  
  • Cancer risk:
    • H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter plays a pivotal role in the development of gastric adenocarcinoma Gastric adenocarcinoma Gastric Cancer over decades (10- to 15- fold increased risk).
    • Mucosa-associated lymphoid tissue Mucosa-associated lymphoid tissue Colon, Cecum, and Appendix: Anatomy ( MALT MALT Colon, Cecum, and Appendix: Anatomy) lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum

Autoimmune metaplastic atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (AMAG)^[9,11,13]

• Chronic corpus-predominant 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 gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis
• Associated with chronic T cell–mediated autoimmune disease:
  • T cells T cells Lymphocytes responsible for cell-mediated immunity. Two types have been identified – cytotoxic (t-lymphocytes, cytotoxic) and helper T-lymphocytes (t-lymphocytes, helper-inducer). They are formed when lymphocytes circulate through the thymus gland and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen. T cells: Types and Functions destroy oxyntic mucosa.
  • Antibodies Antibodies Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution. Immunoglobulins: Types and Functions against parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy and intrinsic factor Intrinsic factor A glycoprotein secreted by the cells of the gastric glands that is required for the absorption of vitamin B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to vitamin B12 deficiency and anemia, pernicious. Gastritis 
  • Effects:
    • Loss of oxyntic glands, replaced by atrophic mucosa → intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation
    • Pathologic changes lead to reduced acid production → hypochlorhydria/ achlorhydria Achlorhydria A lack of hydrochloric acid in gastric juice despite stimulation of gastric secretion. Gastritis → ↑ gastrin Gastrin A family of gastrointestinal peptide hormones that excite the secretion of gastric juice. They may also occur in the central nervous system where they are presumed to be neurotransmitters. Gastrointestinal Secretions (loss of negative feedback Negative feedback Hypothalamic and Pituitary Hormones)
    • Reduced acid → reduced iron absorption Iron absorption Digestion and Absorption
    • Loss of parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy and intrinsic factor Intrinsic factor A glycoprotein secreted by the cells of the gastric glands that is required for the absorption of vitamin B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to vitamin B12 deficiency and anemia, pernicious. Gastritis due to antibodies Antibodies Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution. Immunoglobulins: Types and Functions → vitamin B₁₂ malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion and pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia
• Cancer risk:
  • Gastric neuroendocrine/ carcinoid tumors Carcinoid tumors Carcinoid tumors are small, well-differentiated, slow-growing neuroendocrine tumors (NET). Carcinoid syndrome describes the signs and symptoms associated with unregulated vasoactive hormone production by neuroendocrine tumors. Carcinoid tumors are most commonly found in the GI and bronchopulmonary tracts. Carcinoid Tumors and Syndrome: Elevated gastrin Gastrin A family of gastrointestinal peptide hormones that excite the secretion of gastric juice. They may also occur in the central nervous system where they are presumed to be neurotransmitters. Gastrointestinal Secretions also stimulates enterochromaffin cells → hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation → dysplasia
  • Gastric adenocarcinoma Gastric adenocarcinoma Gastric Cancer

Gastropathies^[9,11]

• Damage to the epithelial lining with no (or minimal) associated 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
• Associated with mucosal injury from destruction of the normal protective barrier (mucins, bicarbonate Bicarbonate Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the ph of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity. Electrolytes, and epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology), which may result in:
  • Erosions Erosions Corneal Abrasions, Erosion, and Ulcers and ulcers
  • Bleeding (hemorrhagic gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis)
• Common causes:
  • Reactive (chemical) gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis
  • Medications: NSAIDs NSAIDS Primary vs Secondary Headaches, 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 salts, others
  • Alcohol
  • Bile Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile acids and salts; cholesterol; and electrolytes. It aids digestion of fats in the duodenum. Gallbladder and Biliary Tract: Anatomy reflux
  • Ischemic gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis:
    • Associated with critical illness (e.g., 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) and injury (e.g., trauma)
    • Represents end-organ failure of 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 in critical illness
  • Vascular gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis:
    • Portal hypertensive (congestive) gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis
    • Gastric antral vascular ectasia Gastric Antral Vascular Ectasia A distinct vascular lesion in the pyloric antrum that is characterized by tortuous dilated blood vessels (ectasia) radiating outward from the pylorus. The vessel pattern resembles the stripes on the surface of a watermelon. This lesion causes both acute and chronic gastrointestinal hemorrhage. Gastrointestinal Bleeding (GAVE)

Clinical Presentation and Diagnosis

Screening Screening Preoperative Care of asymptomatic individuals for H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter is not recommended. Tests are done in symptomatic patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship to evaluate for gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis and peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease. 

Clinical presentation^[8,10]

• May be asymptomatic and present with 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 on lab tests
• Symptoms of acute gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis:
  • Gnawing or burning epigastric pain Epigastric pain Mallory-Weiss Syndrome (Mallory-Weiss Tear), worse after meals
  • 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, sometimes vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia
  • Early satiety Early Satiety Bariatric Surgery
• H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis:
  • Acute: asymptomatic or mild, self-limited dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance
  • Chronic:
    • Dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance
    • Symptoms of peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease (similar symptoms of acute gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis)
    • 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 deficiency or B₁₂-deficiency 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 
• AMAG:
  • May be asymptomatic, but often with dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance
  • B₁₂ deficiency:
    • 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
    • Glossitis
    • Mild cognitive impairment and other neurologic manifestations
  • 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 deficiency 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: occurs earlier than B₁₂ deficiency ( pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia) because of decreased acid secretion Secretion Coagulation Studies
  • Increased association with other autoimmune diseases Autoimmune diseases Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides. Selective IgA Deficiency (e.g., autoimmune thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy disease, type 1 Type 1 Spinal Muscular Atrophy diabetes Diabetes Diabetes 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, Addison’s disease Addison’s Disease Adrenal insufficiency (AI) is the inadequate production of adrenocortical hormones: glucocorticoids, mineralocorticoids, and adrenal androgens. Primary AI, also called Addison’s disease, is caused by autoimmune disease, infections, and malignancy, among others. Adrenal Insufficiency and Addison Disease)
• Other: hematemesis Hematemesis Vomiting of blood that is either fresh bright red, or older ‘coffee-ground’ in character. It generally indicates bleeding of the upper gastrointestinal tract. Mallory-Weiss Syndrome (Mallory-Weiss Tear) (hemorrhagic gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis)

Diagnosis

Indications for H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter testing:^[5]

• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship ≥ 60 years of age or younger patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with alarm symptoms of dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance:
  • Vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia
  • Bleeding or 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
  • Abdominal mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast or unintended weight loss Weight loss Decrease in existing body weight. Bariatric Surgery
  • 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
• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship starting chronic treatment with NSAIDs NSAIDS Primary vs Secondary Headaches or who are taking long-term low-dose aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs)
• Unexplained 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 deficiency 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
• Current peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease ( PUD PUD Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease) or a past history of PUD PUD Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease (without documented cure) 
• The development of upper GI symptoms in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia
• Low-grade gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy–associated lymphoid tissue ( MALT MALT Colon, Cecum, and Appendix: Anatomy) lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum
• History of endoscopic resection of early gastric cancer Gastric cancer Gastric cancer is the 3rd-most common cause of cancer-related deaths worldwide. The majority of cases are from adenocarcinoma. The modifiable risk factors include Helicobacter pylori infection, smoking, and nitrate-rich diets. Gastric Cancer
• Adults with idiopathic Idiopathic Dermatomyositis thrombocytopenic purpura ( ITP ITP Immune thrombocytopenic purpura (ITP), formerly known as idiopathic thrombocytopenic purpura, is a condition that develops secondary to immune-mediated destruction of platelets, resulting in thrombocytopenia (platelet count < 100,000/mm³). Immune thrombocytopenic purpura can be either primary or secondary due to drugs or underlying disease. Immune Thrombocytopenic Purpura) 
• Notes:
  • For patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship < age 60 with uninvestigated dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance without alarming features, noninvasive testing is acceptable.
  • Typical symptoms of GERD GERD Gastroesophageal reflux disease (GERD) occurs when the stomach acid frequently flows back into the esophagus. This backwash (acid reflux) can irritate the lining of the esophagus, causing symptoms such as retrosternal burning pain (heartburn). Gastroesophageal Reflux Disease (GERD) without a history of peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease ( PUD PUD Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease) or dyspepsia Dyspepsia Impaired digestion, especially after eating. Lactose Intolerance do not require H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter testing.

Noninvasive laboratory studies:

• Noninvasive H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter testing:
  • Stool antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination assay (preferred for initial diagnosis and to confirm eradication)
  • Urea breath test Urea breath test Gastritis:
    • Slightly more accurate than stool antigen testing Stool Antigen Testing Entamoeba spp./Amebiasis
    • Capsules with radioactively labeled urea Urea A 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 Cycle (¹³C or ¹⁴C) are swallowed; the urea Urea A 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 Cycle is absorbed.
    • Urease Urease An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. Nocardia/Nocardiosis produced by H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter splits labeled urea Urea A 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 Cycle → produces ¹³C- or ¹⁴C-labeled CO₂, which can be detected in exhaled breaths 20‒30 minutes later by mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast spectrometry or scintillation 
    • If H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter  is not present → unhydrolyzed labeled urea Urea A 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 Cycle is excreted by the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy
    • Note: Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship should discontinue gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis medications (antibiotics, PPIs, bismuth, sucralfate) prior the test to avoid false negative False negative An FN test result indicates a person does not have the disease when, in fact, they do. Epidemiological Values of Diagnostic Tests results.
    • Sensitivity and specificity Sensitivity and Specificity Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. Epidemiological Values of Diagnostic Tests: both > 95%
  • Serologic tests are not recommended.
• AMAG:^[13]
  • CBC: 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 (↓ 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, ↓ B₁₂ level)
  • Serology Serology The study of serum, especially of antigen-antibody reactions in vitro. Yellow Fever Virus:
    • Positive for antibodies Antibodies Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution. Immunoglobulins: Types and Functions to parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy and intrinsic factor Intrinsic factor A glycoprotein secreted by the cells of the gastric glands that is required for the absorption of vitamin B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to vitamin B12 deficiency and anemia, pernicious. Gastritis 
    • Elevated fasting serum gastrin Gastrin A family of gastrointestinal peptide hormones that excite the secretion of gastric juice. They may also occur in the central nervous system where they are presumed to be neurotransmitters. Gastrointestinal Secretions level
    • Low serum pepsinogen I levels or low pepsinogen I/II ratio
    • Screening Screening Preoperative Care for autoimmune thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy disease (due to high risk of concurrent disease)
• EMAG:^[9]
  • Gastrin Gastrin A family of gastrointestinal peptide hormones that excite the secretion of gastric juice. They may also occur in the central nervous system where they are presumed to be neurotransmitters. Gastrointestinal Secretions level is not as elevated as with AMAG.
  • Pernicious anemia Pernicious anemia A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. Megaloblastic Anemia is absent.
  • No autoantibodies Autoantibodies Antibodies that react with self-antigens (autoantigens) of the organism that produced them. Blotting Techniques against parietal cells Parietal cells Rounded or pyramidal cells of the gastric glands. They secrete hydrochloric acid and produce gastric intrinsic factor, a glycoprotein that binds vitamin B12. Stomach: Anatomy and intrinsic factor Intrinsic factor A glycoprotein secreted by the cells of the gastric glands that is required for the absorption of vitamin B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to vitamin B12 deficiency and anemia, pernicious. Gastritis

Esophagogastroduodenoscopy (EGD):^[4,13]

Findings, often nonspecific, may include

• May not have noticeable pathologic changes
• Findings, often nonspecific, may include:
  • Mucosal erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion/friable mucosa
  • Antral nodularity
  • Mucosal erosions Erosions Corneal Abrasions, Erosion, and Ulcers, petechial hemorrhages Petechial Hemorrhages Brown-Séquard Syndrome (erosive gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis)
• Classic appearance of atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis:^[4]
  • Pale mucosa
  • Increased visibility of vasculature
  • Flattening of rugal folds (advanced atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis)
  • Light blue crests and white opaque fields (intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation)

Biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma:^[4,13,14]

• Required for diagnosis of atrophic gastritis Atrophic gastritis Gastritis with atrophy of the gastric mucosa, the gastric parietal cells, and the mucosal glands leading to achlorhydria. Atrophic gastritis usually progresses from chronic gastritis. Gastritis (AMAG, EMAG)^[13]
• Multiple biopsies recommended (corpus and antrum)
• All abnormal-looking areas are biopsied.
• Adjacent normal tissue also included
• Testing for H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter in biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma specimen:^[4,14]
  • Point-of-care PCR PCR Polymerase 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) test kits (can also detect mutations that cause clarithromycin Clarithromycin A 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 resistance Resistance Physiologically, 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)
  • Rapid urease Urease An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. Nocardia/Nocardiosis test (RUT):
    • Urease Urease An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. Nocardia/Nocardiosis produced by H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter liberates ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance from urea Urea A 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 Cycle → alkaline pH pH The quantitative measurement of the acidity or basicity of a solution. Acid-Base Balance changes the color of the reagent
    • If suspicious clinical history but negative RUT → histology
  • Bacterial culture of biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma specimens: of limited use since H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter is fastidious Fastidious Bordetella
• Acute H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis findings:
  •  Presence of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter on histology: curved, flagellated, gram-negative rods
  • Mucosal neutrophils Neutrophils Granular 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 
• Chronic H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis findings:
  • Lymphocytes Lymphocytes Lymphocytes are heterogeneous WBCs involved in immune response. Lymphocytes develop from the bone marrow, starting from hematopoietic stem cells (HSCs) and progressing to common lymphoid progenitors (CLPs). B and T lymphocytes and natural killer (NK) cells arise from the lineage. Lymphocytes: Histology, plasma Plasma The residual portion of blood that is left after removal of blood cells by centrifugation without prior blood coagulation. Transfusion Products cells, eosinophils Eosinophils Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin. Innate Immunity: Phagocytes and Antigen Presentation
  • Lymphoid follicles Lymphoid follicles Secondary Lymphatic Organs 
  • Atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation (if present) typically starts in the antrum and expands proximally.^[13]
• Early AMAG findings:
  • Deep 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, eosinophils Eosinophils Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin. Innate Immunity: Phagocytes and Antigen Presentation
  • Destruction of oxyntic glands
  • Intestinal or pseudopyloric metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation
  • Atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation is typically confined to the corpus and fundus Fundus The superior portion of the body of the stomach above the level of the cardiac notch. Stomach: Anatomy (antral sparing).^[13]
• Advanced AMAG findings:
  • Metaplastic glands replace the oxyntic glands.
  • Megaloblastic epithelial cells

Management and Complications

General principles^[3–6]

• Acid reduction with proton pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols inhibitors (PPIs)
• B₁₂ replacement therapy
• 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 deficiency treatment
• Avoid direct gastric irritants
• Treatment for H. pylori is guided by penicillin Penicillin Rheumatic Fever allergy Allergy An abnormal adaptive immune response that may or may not involve antigen-specific IgE Type I Hypersensitivity Reaction or risk factors for macrolide resistance Resistance Physiologically, 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.

H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter–associated gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis management^[4,5] 

• Treatment aimed to eradicate H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter
• Initial eradication regimen for patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship without risk factors for macrolide resistance Resistance Physiologically, 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 (“triple therapy” PPI-AC) for 14 days:
  • PPI (at standard or double dose): omeprazole Omeprazole A 4-methoxy-3, 5-dimethylpyridyl, 5-methoxybenzimidazole derivative of timoprazole that is used in the therapy of stomach ulcers and zollinger-ellison syndrome. The drug inhibits an h(+)-k(+)-exchanging ATPase which is found in gastric parietal cells. Gastric Acid Drugs 20‒40 mg twice a day, PLUS
  • Clarithromycin Clarithromycin A 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 a day PLUS
  • Amoxicillin Amoxicillin A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration. Penicillins 1000 mg twice a day
    • For penicillin Penicillin Rheumatic Fever allergies Allergies A medical specialty concerned with the hypersensitivity of the individual to foreign substances and protection from the resultant infection or disorder. Selective IgA Deficiency, can substitute metronidazole Metronidazole A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. Pyogenic Liver Abscess 
    • Dosing options: 400 mg 4 times daily or 500 mg 3 times daily
• Alternative PPIs can be used for eradication:
  • Lansoprazole Lansoprazole A 2, 2, 2-trifluoroethoxypyridyl derivative of timoprazole that is used in the therapy of stomach ulcers and zollinger-ellison syndrome. The drug inhibits h(+)-k(+)-exchanging ATPase which is found in gastric parietal cells. Lansoprazole is a racemic mixture of (r)- and (s)-isomers. Gastric Acid Drugs 30 mg twice a day
  • Pantoprazole Pantoprazole 2-pyridinylmethylsulfinylbenzimidazole proton pump inhibitor that is used in the treatment of gastroesophageal reflux and peptic ulcer. Gastric Acid Drugs 40‒80 mg twice a day
  • Rabeprazole Rabeprazole A 4-(3-methoxypropoxy)-3-methylpyridinyl derivative of timoprazole that is used in the therapy of stomach ulcers and zollinger-ellison syndrome. The drug inhibits h(+)-k(+)-exchanging ATPase which is found in gastric parietal cells. Gastric Acid Drugs 20‒40 mg twice a day
  • Esomeprazole 40 mg once a day
• For patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship in areas where the clarithromycin Clarithromycin A 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 resistance Resistance Physiologically, 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 is rate > 15% or for patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who had recent macrolide exposure (“quadruple therapy”) for 7‒14 days:
  • PPI regimen (same as above), PLUS
  • Bismuth subsalicylate Bismuth Subsalicylate Antidiarrheal Drugs 300 mg 4 times a day, PLUS
  • Metronidazole Metronidazole A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. Pyogenic Liver Abscess 250‒500 mg 4 times a day, PLUS
  • Tetracycline Tetracycline A naphthacene antibiotic that inhibits amino Acyl tRNA binding during protein synthesis. Drug-Induced Liver Injury 500 mg 4 times a day
• Alternatives for multidrug-resistant strains of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter:
  • PPI + amoxicillin Amoxicillin A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration. Penicillins (or metronidazole Metronidazole A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. Pyogenic Liver Abscess) + rifabutin Rifabutin A broad-spectrum antibiotic that is being used as prophylaxis against disseminated Mycobacterium avium complex infection in HIV-positive patients. Diseases of the Uvea 300 mg once daily, or 
  • PPI + amoxicillin Amoxicillin A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration. Penicillins (or metronidazole Metronidazole A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. Pyogenic Liver Abscess) + levofloxacin Levofloxacin The l-isomer of ofloxacin. Fluoroquinolones 250–500 mg daily for 10‒14 days

Confirmation of eradication^[4,5]

• Hold PPI for 1–2 weeks prior to testing.
• Test all patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship ≥ 4 weeks after completion of antibiotic therapy with any of these:
  • Urea breath test Urea breath test Gastritis
  • Stool antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination test
  • EGD 
• Approximately 20% of H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter cases fail to be eradicated by the initial attempt.
  • If infection persists, try to use different antibiotics, and/or test for antibiotic susceptibility by culture or molecular ( PCR PCR Polymerase 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)) methods (less sensitive). 
  • Preferred options typically include:
    • Quadruple therapy with bismuth for 14 days
    • Triple therapy with levofloxacin Levofloxacin The l-isomer of ofloxacin. Fluoroquinolones (PPI + amoxicillin Amoxicillin A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration. Penicillins + levofloxacin Levofloxacin The l-isomer of ofloxacin. Fluoroquinolones) for 14 days
    • High-dose dual therapy with PPI + amoxicillin Amoxicillin A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration. Penicillins 1000 mg 3 times a day
• Note: Despite eradication, normal gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy may not recover from significant atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation → cancer risk remains elevated (especially for OLGA stages III and IV)

AMAG management^[4,13] 

• No specific treatment other than H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter eradication
• Surveillance Surveillance Developmental Milestones and Normal Growth 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) every 3–5 years to look for signs of cancer is controversial and not agreed on, but recommendation is found in the 2019 European Society for Gastrointestinal 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) (ESGE) guidelines.^[7]
• Evaluate for:
  • 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 and vitamin B-12 deficiencies
  • Other autoimmune diseases Autoimmune diseases Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides. Selective IgA Deficiency (e.g., autoimmune thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy disease, type 1 Type 1 Spinal Muscular Atrophy diabetes Diabetes Diabetes 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, Addison disease)

Complications^[4]

• Peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease: requires continued acid suppression Suppression Defense Mechanisms for 4 to 8 weeks
• Intestinal-type gastric cancer Gastric cancer Gastric cancer is the 3rd-most common cause of cancer-related deaths worldwide. The majority of cases are from adenocarcinoma. The modifiable risk factors include Helicobacter pylori infection, smoking, and nitrate-rich diets. Gastric Cancer:
  • Associated with AMAG and EMAG
  • Progression of mucosal atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation to intestinal metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation
  • Metaplasia Metaplasia A condition in which there is a change of one adult cell type to another similar adult cell type. Cellular Adaptation progresses to dysplasia and eventually to invasive adenocarcinoma.
• MALToma MALToma Extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue (also called MALToma, MALT lymphoma, and pseudolymphoma) is a group of non-Hodgkin’s lymphomas that have historically been grouped together because they appear to arise from postgerminal center marginal zone B cells and share a similar immunophenotype. MALT Lymphoma (mucosa-associated lymphoid tumor Tumor Inflammation):
  • B-cell lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum of 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
  • Clear association with H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter infection
  • Some cases are cured with H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter eradication

Differential Diagnosis

• Ménétrier’s disease (MD): protein-losing gastropathy gastropathy Damage to the epithelial lining with no or minimal associated inflammation and is technically a separate entity from gastritis Gastritis characterized by giant hyperplastic Hyperplastic Colon Polyps mucosal folds of 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 body and fundus Fundus The superior portion of the body of the stomach above the level of the cardiac notch. Stomach: Anatomy. MD presents with abdominal pain Abdominal Pain Acute Abdomen, 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, but associated weight loss Weight loss Decrease in existing body weight. Bariatric Surgery and 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 can help differentiate MD from gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis. Further evaluation via EGD and biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma can help confirm MD.
• Peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease ( PUD PUD Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease): full-thickness ulcer involving the gastric or duodenal wall. Peptic ulcer Peptic ulcer Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease presents with abdominal pain Abdominal Pain Acute Abdomen, 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/ vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and, sometimes, upper gastrointestinal bleed. PUD PUD Peptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease is also associated with H. pylori H. pylori A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus campylobacter, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus Helicobacter. It has been officially transferred to Helicobacter gen. Helicobacter. Diagnosis is made 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)
• Cholelithiasis Cholelithiasis Cholelithiasis (gallstones) is the presence of stones in the gallbladder. Most gallstones are cholesterol stones, while the rest are composed of bilirubin (pigment stones) and other mixed components. Patients are commonly asymptomatic but may present with biliary colic (intermittent pain in the right upper quadrant). Cholelithiasis/ cholecystitis Cholecystitis Cholecystitis is the inflammation of the gallbladder (GB) usually caused by the obstruction of the cystic duct (acute cholecystitis). Mechanical irritation by gallstones can also produce chronic GB inflammation. Cholecystitis is one of the most common complications of cholelithiasis but inflammation without gallstones can occur in a minority of patients. Cholecystitis: gallstones Gallstones Cholelithiasis (gallstones) is the presence of stones in the gallbladder. Most gallstones are cholesterol stones, while the rest are composed of bilirubin (pigment stones) and other mixed components. Patients are commonly asymptomatic but may present with biliary colic (intermittent pain in the right upper quadrant). Cholelithiasis obstructing cystic Cystic Fibrocystic Change duct ( cholelithiasis Cholelithiasis Cholelithiasis (gallstones) is the presence of stones in the gallbladder. Most gallstones are cholesterol stones, while the rest are composed of bilirubin (pigment stones) and other mixed components. Patients are commonly asymptomatic but may present with biliary colic (intermittent pain in the right upper quadrant). Cholelithiasis) that can be associated with 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 of the gallbladder Gallbladder The gallbladder is a pear-shaped sac, located directly beneath the liver, that sits on top of the superior part of the duodenum. The primary functions of the gallbladder include concentrating and storing up to 50 mL of bile. Gallbladder and Biliary Tract: Anatomy ( cholecystitis Cholecystitis Cholecystitis is the inflammation of the gallbladder (GB) usually caused by the obstruction of the cystic duct (acute cholecystitis). Mechanical irritation by gallstones can also produce chronic GB inflammation. Cholecystitis is one of the most common complications of cholelithiasis but inflammation without gallstones can occur in a minority of patients. Cholecystitis). Cholecystitis Cholecystitis Cholecystitis is the inflammation of the gallbladder (GB) usually caused by the obstruction of the cystic duct (acute cholecystitis). Mechanical irritation by gallstones can also produce chronic GB inflammation. Cholecystitis is one of the most common complications of cholelithiasis but inflammation without gallstones can occur in a minority of patients. Cholecystitis commonly presents with right upper quadrant Right upper quadrant Anterior Abdominal Wall: Anatomy and epigastric pain Epigastric pain Mallory-Weiss Syndrome (Mallory-Weiss Tear), 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. Unlike gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis, the condition is frequently associated with right upper quadrant Right upper quadrant Anterior Abdominal Wall: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and tenderness.
• Viral 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: acute self-limited illness associated with diffuse abdominal pain Abdominal Pain Acute Abdomen, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and 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. Watery diarrhea Watery diarrhea Rotavirus can help differentiate this condition from acute gastritis Gastritis Gastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting. Gastritis.
• Pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis: 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 of the pancreas Pancreas The pancreas lies mostly posterior to the stomach and extends across the posterior abdominal wall from the duodenum on the right to the spleen on the left. This organ has both exocrine and endocrine tissue. Pancreas: Anatomy; can be acute or chronic. Pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis usually presents with epigastric pain Epigastric pain Mallory-Weiss Syndrome (Mallory-Weiss Tear) radiating to the back, 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, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and bloating Bloating Constipation. Bloodwork will show elevated amylase Amylase A group of amylolytic enzymes that cleave starch, glycogen, and related alpha-1, 4-glucans. Digestion and Absorption and lipase Lipase An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. Malabsorption and Maldigestion.