What is the medical management of gastritis?

Medical Management of Gastritis

Confirm Diagnosis with Endoscopic Biopsy

All suspected gastritis requires endoscopic confirmation with histopathological examination, as symptoms alone are insufficient for diagnosis. 1

• Obtain biopsies from both the gastric body and antrum/incisura at minimum, placing them in separately labeled containers to assess distribution and extent of disease 1
• Recognize that intestinal metaplasia on histology almost invariably indicates underlying atrophic gastritis, even when not explicitly stated in pathology reports 1
• Distinguish true gastritis (characterized by significant inflammatory cell infiltration including neutrophils, lymphocytes, and plasma cells) from reactive gastropathy (which lacks significant inflammation) 2

Test and Treat H. pylori Infection

Every patient with confirmed gastritis must be tested for H. pylori infection, and if positive, receive eradication therapy. 1

• Administer appropriate antibiotic therapy for 10-14 days 1
• Triple therapy regimens (such as proton pump inhibitor with clarithromycin and amoxicillin) achieve eradication in the majority of cases and lead to resolution of acute inflammatory changes within 4-5 weeks 3
• Confirm successful eradication using non-serological testing modalities 1
• Resolution of gastritis occurs in most cases after successful eradication, though severe gastritis may cause irreparable mucosal damage with persistent scarring and atrophy 3

Acid Suppression Therapy

Proton pump inhibitors are the cornerstone of symptomatic management and mucosal healing. 4

• Omeprazole and other PPIs reduce gastric acid production and are used for healing of gastritis-related complications 4
• Take PPIs at the lowest effective dose for the shortest duration needed, typically before meals 4
• Be aware of serious side effects with prolonged use (>1 year), including:
  • Tubulointerstitial nephritis 4
  • Clostridium difficile infection risk 4
  • Bone fractures (hip, wrist, spine) with long-term multiple daily doses 4
  • Cutaneous and systemic lupus erythematosus 4
  • Hypomagnesemia after ≥3 months of therapy 4
  • Vitamin B12 deficiency with therapy >3 years 4
  • Fundic gland polyps with long-term use 4

Manage Autoimmune Gastritis

Evaluate for both vitamin B12 and iron deficiency anemia, as autoimmune gastritis causes loss of intrinsic factor and reduced acid output leading to malabsorption. 1

• Screen for type 1 gastric neuroendocrine tumors with upper endoscopy 1
• Remove small neuroendocrine tumors endoscopically 1
• Follow with surveillance endoscopy every 1-2 years depending on tumor burden 1
• Patients with new pernicious anemia who have not had recent endoscopy should undergo endoscopy with topographical biopsies to confirm corpus-predominant atrophy, stratify risk, and exclude prevalent gastric neoplasia 1

Implement Surveillance for Atrophic Gastritis

Atrophic gastritis represents a preneoplastic condition with progressive gastric cancer risk requiring endoscopic surveillance. 1

• Consider surveillance endoscopy every 3 years for patients with advanced atrophic gastritis 1
• The severity of atrophy and presence of intestinal metaplasia determine cancer risk and surveillance intervals 1, 5
• Chronic atrophic gastritis causes achlorhydria and chronic luminal alkalosis, which favors intestinal metaplasia development 5

Address Reactive Gastropathy Differently

Reactive gastropathy requires identification and removal of the offending agent rather than antimicrobial or immunosuppressive therapy. 1, 2

• Common causes include NSAIDs, alcohol, bile reflux, and portal hypertension 6, 7
• Treatment focuses on discontinuing the causative agent 2
• The cancer risk of reactive gastropathy is not well-established, unlike atrophic gastritis which requires surveillance 2

Important Drug Interactions and Precautions

• Avoid concomitant use of omeprazole with clopidogrel, as it reduces clopidogrel's antiplatelet activity 4
• Avoid concomitant use with St. John's Wort or rifampin, which substantially decrease omeprazole concentrations 4
• Temporarily stop PPI treatment at least 14 days before assessing serum chromogranin A levels to avoid false positive results for neuroendocrine tumors 4
• Consider temporary PPI withdrawal in patients receiving high-dose methotrexate due to risk of elevated methotrexate levels and toxicity 4

Special Populations

• Reduce omeprazole dosage to 10 mg once daily for patients with hepatic impairment (Child-Pugh Class A, B, or C) 4
• Reduce omeprazole dosage to 10 mg once daily for Asian patients due to approximately four-fold higher exposure 4
• Monitor magnesium levels in patients on prolonged PPI therapy, especially those taking digoxin or diuretics 4