In a 49-year-old man who was treated for H. pylori–associated duodenal ulcer with omeprazole and a full course of eradication antibiotics and is now asymptomatic with a normal exam, what is the appropriate next step to confirm eradication?

Test of Cure with Urea Breath Test or Stool Antigen—Not Serology

In this asymptomatic 49-year-old man who completed H. pylori eradication therapy for duodenal ulcer, perform a non-invasive test of cure using either urea breath test or monoclonal stool antigen test at least 4 weeks after completing antibiotics—serology has no role because antibodies persist for months after successful eradication. 1, 2

Why Test of Cure is Mandatory

• Confirmation of eradication is now standard of care for all patients treated for H. pylori-associated peptic ulcer disease, as successful eradication eliminates the excess peptic-ulcer mortality risk and prevents ulcer recurrence in over 90% of cases. 1, 2
• Persistent H. pylori infection after treatment is a negative prognostic marker—ulcer recurrence occurs in approximately 84% of patients with persistent infection versus only 19% in those with confirmed eradication. 1, 3
• Even though this patient is asymptomatic, symptom resolution does not confirm eradication—many patients feel better temporarily while H. pylori persists, only to develop recurrent ulcers later. 2

Correct Testing Method: Non-Serological Tests Only

Use either:

• Urea breath test (UBT): Gold standard with sensitivity 94.7–97% and specificity 95–100%. 1, 2, 4
• Laboratory-based validated monoclonal stool antigen test: Equally accurate alternative with sensitivity and specificity >90%. 1, 2, 4

Both tests detect active infection, not past exposure, making them ideal for post-treatment assessment. 2

Why Serology is Wrong

H. pylori antibody testing is completely inappropriate for test of cure because IgG antibodies remain elevated in the blood for 6–12 months after successful bacterial eradication—a positive antibody test after treatment does not indicate treatment failure. 1, 2, 5

• While a 50% fall in antibody titers can indicate eradication, this requires 6 months, simultaneous measurement of paired sera, and a validated test kit—making it impractical and inferior to breath or stool testing. 1, 5
• This is the most common error in post-treatment management—misinterpreting persistent antibody positivity as treatment failure leads to unnecessary repeat antibiotic courses, fueling antimicrobial resistance. 2

Critical Timing and Preparation Requirements

Wait at least 4 weeks after completing antibiotics before testing to allow gastric mucosa recovery and avoid false-negative results from temporary bacterial suppression rather than true eradication. 1, 2, 4

Before testing, ensure proper medication washout:

• Discontinue proton pump inhibitors (PPIs) for at least 2 weeks (preferably 7–14 days). 2, 4
• Discontinue antibiotics and bismuth for at least 4 weeks. 2, 4
• Patient should fast for at least 6 hours before breath testing. 2, 4

Testing too early (before 4 weeks) or without adequate PPI washout will yield unreliable results. 2, 4

Why Repeat Endoscopy is Not Indicated

Repeat EGD is unnecessary in this asymptomatic patient with uncomplicated duodenal ulcer because:

• Non-invasive testing is sufficient for confirming eradication in uncomplicated duodenal ulcer. 1, 2
• Endoscopy-based testing is reserved for specific high-risk scenarios: gastric ulcer (to exclude malignancy and confirm healing), complicated peptic ulcer disease, gastric MALT lymphoma, or when histological assessment of mucosal abnormalities is needed. 1, 2, 4
• This patient had duodenal (not gastric) ulcer and is now asymptomatic with normal exam—no indication for invasive testing. 2

Management After Test Results

If eradication is confirmed:

• No further H. pylori testing is needed unless symptoms recur. 2, 4
• Discontinue PPI therapy—prolonged acid suppression is not recommended after successful eradication in uncomplicated duodenal ulcer. 2, 4
• Ulcer healing is achieved in 98% of patients with confirmed eradication, even if the ulcer initially persisted after treatment. 6

If eradication fails:

• Use a completely different antibiotic regimen—never repeat the same antibiotics that failed. 2
• If first-line was clarithromycin-based triple therapy: switch to 14-day bismuth quadruple therapy or 14-day levofloxacin triple therapy. 2
• After two treatment failures, pursue antibiotic susceptibility testing to guide third-line therapy. 1, 2

Common Pitfalls to Avoid

• Do not interpret persistent antibody positivity as treatment failure—this leads to unnecessary retreatment and antibiotic resistance. 2
• Do not skip test of cure based on symptom resolution—asymptomatic patients can still harbor H. pylori and develop recurrent ulcers. 2
• Do not test before 4 weeks or without proper PPI washout—this yields false results. 2, 4
• Do not use serology for any post-treatment assessment—it cannot distinguish active infection from past exposure. 1, 2