Gastritis
BASICS
- Inflammation of gastric mucosa
- Acute: neutrophilic infiltration; Chronic: mononuclear infiltration (lymphocytes, macrophages)
- Subtypes: erosive, reflux, hemorrhagic, infectious (H. pylori, CMV, EBV), atrophic (autoimmune), granulomatous (Crohn, sarcoidosis)
- Common in elderly, rare in children (except H. pylori)
EPIDEMIOLOGY
- Affects all adults; incidence increases with age
- Equal sex distribution except autoimmune gastritis (female > male)
- ~50% >60 years infected with H. pylori; higher in minorities, immigrants, low SES
ETIOLOGY AND PATHOPHYSIOLOGY
- Noxious agents disrupt mucosal barrier → epithelial injury
- Causes: H. pylori (most common), NSAIDs, alcohol, bile reflux, viral infections, stress
- Autoimmune gastritis linked to pernicious anemia and gastric cancer risk
- Genetic factors (TLR1) under investigation
RISK FACTORS
- Age >60 years
- NSAIDs, alcohol, tobacco
- ICU patients with hypovolemia/hypoxia
- Autoimmune diseases (thyroiditis, diabetes type 1, Addison's)
- Family history of H. pylori or gastric cancer
GENERAL PREVENTION
- Avoid mucosal irritants (NSAIDs, alcohol, tobacco)
- ICU prophylaxis with H2 blockers, PPIs, prostaglandins, sucralfate
- Test and treat H. pylori in long-term NSAID users or endemic populations
COMMONLY ASSOCIATED CONDITIONS
- Peptic ulcer disease
- Pernicious anemia
- Portal hypertension gastropathy
- MALT lymphoma
DIAGNOSIS
History
- Burning epigastric pain, worse with eating
- Nausea, vomiting, weight loss
- Possible GI bleeding (melena, hematemesis)
- Neurologic symptoms if B12 deficiency (atrophic gastritis)
- Risk factor inquiry: NSAIDs, alcohol, autoimmune disorders
Physical Exam
- Often normal; mild epigastric tenderness
- Signs of anemia or chronic alcohol use
Differential Diagnosis
- Dyspepsia (functional abdominal pain)
- Peptic ulcer disease
- Gastric cancer
- Pancreatitis or biliary disease
DIAGNOSTIC TESTS & INTERPRETATION
- Stool antigen and 13C-urea breath test for H. pylori (95% sensitivity/specificity)
- Serum IgG for H. pylori (less useful post-treatment)
- Endoscopy with biopsy for histology, rapid urease test, culture, PCR
- Lab evaluation for anemia, B12 deficiency
- Hold PPIs 2 weeks, H2 blockers 24 hours, antibiotics 4 weeks before testing
TREATMENT
General Measures
- Eradicate H. pylori if present
- Discontinue NSAIDs, alcohol, tobacco
- Supportive care with fluids if needed
Medications
- Antacids and H2 blockers for symptom relief
- PPIs if refractory to H2 blockers
- H. pylori treatment:
- Clarithromycin triple therapy (amoxicillin/metronidazole + clarithromycin + PPI) 14 days
- Bismuth quadruple therapy for resistant strains or penicillin allergy
- Levofloxacin-based therapy for multiple failures
- Probiotics may reduce symptoms but do not eradicate H. pylori
Pregnancy
- Avoid certain antacids (sodium carbonate, magnesium trisilicate)
- Defer H. pylori treatment if possible
SURGERY/OTHER PROCEDURES
- Rarely required except for phlegmonous gastritis or high-grade dysplasia
COMPLEMENTARY & ALTERNATIVE MEDICINE
- Cranberry, garlic, curcumin, ginger, Pistacia gum may have anti-inflammatory effects
ONGOING CARE
- Confirm eradication >4 weeks post-therapy
- Repeat endoscopy if severe disease or poor response
- Surveillance for atrophic gastritis and dysplasia as indicated
DIET
- Bland diet during symptoms
- Avoid caffeine, spicy foods, alcohol, peppermint, carbonated drinks, high fat
PATIENT EDUCATION
- Smoking cessation and alcohol limitation
- Avoid NSAIDs
- Relaxation techniques
PROGNOSIS
- Generally good with treatment
- Phlegmonous gastritis carries 40-50% mortality
COMPLICATIONS
- Mucosal bleeding, ulceration
- Gastric outlet obstruction
- Gastric intestinal metaplasia and cancer risk
- Atrophic gastritis associated with neuroendocrine tumors and adenocarcinoma
REFERENCES
- Yang H, Guan L, Hu B. Detection and treatment of Helicobacter pylori: problems and advances. Gastroenterol Res Pract. 2022;2022:4710964.
- Malfertheiner P, Megraud F, O'Morain CA, et al; European Helicobacter and Microbiota Study Group. Management of Helicobacter pylori infection—the Maastricht V/Florence consensus report. Gut. 2017;66(1):6-30.
- Chey WD, Leontiadis GI, Howden CW, et al. ACG clinical guideline: treatment of Helicobacter pylori infection. Am J Gastroenterol. 2017;112(2):212-239.
- Buzás GM, Birinyi P. Newer, older, and alternative agents for the eradication of Helicobacter pylori infection: a narrative review. Antibiotics (Basel). 2023;12(6):946.
CODES
- ICD10: K29.5 Unspecified chronic gastritis
- ICD10: K29.40 Chronic atrophic gastritis without bleeding
- ICD10: K29.50 Unspecified chronic gastritis without bleeding
CLINICAL PEARLS
- H. pylori is the leading cause of gastritis; >50% adults colonized by age 60.
- Antibody tests for H. pylori should not be used to assess eradication.
- Stool antigen and urea breath tests are reliable for diagnosis and post-treatment follow-up.
- Discontinue PPIs 2 weeks prior to endoscopy to improve diagnostic accuracy.
- Multiple treatment regimens may be needed for eradication due to resistance.