Helicobacter pylori (H. pylori) infection is the major cause of peptic ulcer disease. Immediately following infection, H. pylori causes acute gastritis. Some individuals spontaneously clear H. pylori, but most develop persistent infection, which leads to chronic active gastritis. An estimated 16% of infected individuals in the United States develop duodenal ulcers.
Patients who present with bleeding ulcers or erosions should undergo endoscopy and biopsies should be taken from a lesion-free area of the gastric body and antral mucosa. Biopsies should be tested for H. pylori with a rapid urease test. Sensitivity and specificity for active infection both exceed 90%. Sensitivity is decreased to approximately 75% in patients taking proton pump inhibitors, bismuth containing medications or antibiotics.
Patients with H. pylori infection should receive antibiotic therapy because treatment significantly reduces the risk of recurrent bleeding ulcers. Approximately 4 weeks following cessation of therapy, patients should be tested for eradication of H. pylori with either a urea breath test or stool antigen test. If a patient is undergoing repeat endoscopy, a gastric biopsy can be tested with the rapid urease test.
Patients must not receive bismuth or antibiotics for at least 4 weeks and should not receive proton-pump inhibitors for at least 2 weeks before testing to avoid false negative results. Histamine H2-receptor antagonists are permissible.
NEJM Resident e-Bulletin, Teaching Topics, June 16, 2016