When to Repeat H. pylori Test After Treatment
Test for H. pylori eradication at least 4 weeks after completing treatment using either a urea breath test or validated monoclonal stool antigen test. 1, 2
Timing of Test of Cure
Wait a minimum of 4 weeks after treatment completion before testing to allow adequate gastric mucosa recovery and avoid false-negative results from temporary bacterial suppression rather than true eradication. 1, 2
Testing before 4 weeks yields unreliable results because the gastric mucosa requires adequate recovery time. 1, 2
For bleeding peptic ulcers specifically, delay testing to 4-8 weeks after the bleeding episode to ensure accurate results. 1, 2
Who Requires Mandatory Confirmation Testing
All patients should undergo test of cure after H. pylori treatment, but it is particularly critical in these high-risk scenarios:
Complicated peptic ulcer disease - persistent infection is a negative prognostic marker for ulcer recurrence and complications. 1, 2
All gastric ulcers - these patients require endoscopic follow-up to ensure complete healing and confirmed eradication. 1, 2
Low-grade gastric MALT lymphoma - treatment failure requires alternative therapies. 3, 1, 2
Cases with poor compliance or low treatment efficacy - higher risk of treatment failure. 1, 2
Bleeding ulcer complications - to guide ongoing PPI management. 1, 2
Recommended Testing Methods
Non-invasive testing is preferred for most patients:
Urea breath test (UBT) - sensitivity 94.7-97% and specificity 95-100%, considered the gold standard for follow-up. 1, 2
Validated monoclonal stool antigen test - sensitivity and specificity >90%, equally accurate alternative to UBT. 1, 2
Endoscopy with biopsy - reserved for specific high-risk scenarios including gastric ulcer, complicated peptic ulcer disease, and gastric MALT lymphoma. 1, 2
Critical Pre-Testing Requirements
Medication washout is essential to avoid false-negative results:
Stop proton pump inhibitors (PPIs) for at least 2 weeks, preferably 7-14 days before testing. 1, 2
Discontinue antibiotics and bismuth for at least 4 weeks before testing. 1, 2
Patients should fast for at least 6 hours before testing. 1
Common Pitfalls to Avoid
Never use serology for test of cure - antibody levels remain elevated after eradication and cannot distinguish active from past infection. 1, 2
Never test too early - results before 4 weeks are unreliable due to temporary bacterial suppression. 1, 2
Never skip PPI washout - inadequate washout causes false-negative results. 1, 2
Management Based on Test Results
If eradication is confirmed:
Discontinue PPI in uncomplicated duodenal ulcer patients. 1, 2
Continue PPI in gastric ulcer patients until complete healing is confirmed. 1, 2
Continue PPI in complicated duodenal ulcer or bleeding ulcer patients until eradication is confirmed. 1, 2
No further H. pylori testing is needed unless symptoms recur in the future. 1
If H. pylori persists after initial treatment:
Use a completely different antibiotic regimen, avoiding antibiotics used previously. 1, 2
Consider 14-day levofloxacin triple therapy or 14-day bismuth quadruple therapy if not previously used. 1, 2, 4
After two treatment failures, pursue antimicrobial susceptibility testing to guide third-line therapy. 1, 2, 4
Never simply repeat the same failed regimen - this leads to further resistance and treatment failure. 1, 2