Gastrointestinal Disorders

Introduction to Atrophic Gastritis

The treatment of atrophic gastritis should focus on H. pylori eradication when present, micronutrient supplementation, and endoscopic surveillance for neoplastic complications based on risk stratification, as recommended by the European Society for Gastrointestinal Endoscopy 1

Diagnostic tests for H. pylori infection include 13C-Urea Breath Test (UBT) with 95% sensitivity and 95% specificity, Stool Antigen Test (SAT) with 88-90% sensitivity and 91-100% specificity, and ELISA with 90% sensitivity and 95% specificity, as recommended by the European Society of Gastrointestinal Endoscopy and the American Gastroenterological Association 2, 3, 4
Upper endoscopy with targeted biopsies is the gold standard for diagnosing acute gastritis, with additional testing for H. pylori infection, as recommended by the American Gastroenterological Association 1
Biopsy protocol should include obtaining biopsies from both antrum and body/corpus, targeting any visible abnormal areas, and topographical biopsies to determine anatomic extent and histologic severity, as recommended by the American Gastroenterological Association 1
Complete blood count (CBC) and serum chemistries are used to assess for anemia, infection, and overall health status in patients with gastritis, as recommended by the American Gastroenterological Association 5, 6
Iron studies and vitamin B12 levels are particularly important in chronic gastritis, as recommended by the American Gastroenterological Association 6

Iron deficiency is present in up to 50% of patients with corpus-predominant atrophic gastritis, and oral or parenteral iron supplementation is recommended based on severity, as recommended by the European Society for Gastrointestinal Endoscopy 1
Vitamin B12 deficiency is common in autoimmune atrophic gastritis, and parenteral vitamin B12 supplementation and regular monitoring of B12 levels are recommended, as recommended by the European Society for Gastrointestinal Endoscopy 1

Routine screening should evaluate for iron and vitamin B12 deficiency in all patients with atrophic gastritis, especially if corpus-predominant, as recommended by the European Society for Gastrointestinal Endoscopy 1
The European Society for Gastrointestinal Endoscopy recommends surveillance every 3-5 years, with intervals adjusted based on risk stratification factors such as family history of gastric cancer and smoking history, as recommended by the European Society for Gastrointestinal Endoscopy 1

The recommended first-line treatment for H. pylori infection is a proton pump inhibitor (PPI)-based triple therapy, consisting of PPI, amoxicillin, and clarithromycin or metronidazole for 14 days, as recommended by the American Gastroenterological Association and the European Society of Pediatric Gastroenterology, Hepatology and Nutrition 7, 8
Clarithromycin should only be used in areas with <15-20% resistance, as recommended by the European Society of Pediatric Gastroenterology, Hepatology and Nutrition 2
The American Gastroenterological Association recommends considering using "Access group" antibiotics over "Watch group" antibiotics when possible, to promote antimicrobial stewardship principles, as recommended by the American Gastroenterological Association 9

Defer treatment until after pregnancy whenever possible, and consider triple therapy with amoxicillin, clarithromycin, and PPI if treatment cannot be deferred, with standard dosing of PPI, amoxicillin, and clarithromycin, and a reported cure rate of 80-90%, as recommended by the American College of Gastroenterology, and metronidazole should be avoided in the first trimester, and tetracycline and quinolones are contraindicated throughout pregnancy, as recommended by the American College of Gastroenterology 2, 10, 11

The urea breath test (UBT) performed at least 4 weeks after completion of therapy is the recommended method for confirming eradication of H. pylori infection, with a sensitivity and specificity of 95%, as recommended by the American Gastroenterological Association and the European Society of Pediatric Gastroenterology, Hepatology and Nutrition 11, 2
The stool antigen test (SAT) is an alternative method for confirming eradication, with a sensitivity of 88-90% and specificity of 91-100%, and should be performed at least 4 weeks after completion of therapy, as recommended by the American Gastroenterological Association and the European Society of Pediatric Gastroenterology, Hepatology and Nutrition 2, 12, 13

For NETs <1 cm, endoscopic resection and surveillance endoscopy every 1-2 years are recommended, depending on NET burden, as recommended by the European Society for Gastrointestinal Endoscopy 1
For NETs 1-2 cm, endoscopic ultrasound is recommended to assess invasion depth and local metastasis, with management based on findings, as recommended by the European Society for Gastrointestinal Endoscopy 1
For NETs >2 cm or with invasion/metastasis, surgical resection is recommended, as recommended by the European Society for Gastrointestinal Endoscopy 1

Screen for autoimmune thyroid disease in patients with autoimmune atrophic gastritis, as recommended by the European Society for Gastrointestinal Endoscopy 1
Consider evaluation for other autoimmune diseases, such as type 1 diabetes mellitus and Addison's disease, when clinically indicated, as recommended by the European Society for Gastrointestinal Endoscopy 1
The risk of gastric adenocarcinoma is highest within the first year of pernicious anemia diagnosis, as recommended by the European Society for Gastrointestinal Endoscopy 1

The primary signs and symptoms of gastritis include epigastric pain, nausea, vomiting, bloating, indigestion, and loss of appetite, though many patients may be asymptomatic despite histological evidence of inflammation, as reported by the American College of Radiology 14
Certain symptoms, such as hematemesis, melena, unintentional weight loss, progressive dysphagia, persistent vomiting, anemia, and age >45 years with new-onset symptoms, warrant immediate evaluation, as recommended by the American College of Radiology 14
H. pylori testing and treatment is primarily indicated for uninvestigated dyspepsia in populations with high H. pylori prevalence (≥20%), peptic ulcer disease, gastric cancer prevention, and specific conditions like MALT lymphoma, as recommended by the European Society of Gastrointestinal Endoscopy and supported by the American Gastroenterological Association 2, 8
Testing for H. pylori during pregnancy should be limited to specific clinical scenarios, such as active peptic ulcer disease, severe refractory symptoms, or unexplained iron deficiency anemia not responding to iron supplementation, as suggested by the American Gastroenterological Association 15