Different effects of short-term omeprazole, lansoprazole or pantoprazole on the accuracy of the 13C-urea breath test

BACKGROUND: Proton pump inhibitors may interfere with the accuracy of the (13)C-urea breath test, but little information is available on the effect of standard doses of various proton pump inhibitors on this test. AIM: To evaluate the effect of short-term standard doses of omeprazole, lansoprazole and pantoprazole on the accuracy of the standardized (13)C-urea breath test. METHODS: A total of 124 patients with Helicobacter pylori infection, diagnosed on the basis of gastric histology, rapid urease test and (13)C-urea breath test, were studied. These patients received omeprazole, 20 mg/day, lansoprazole, 30 mg/day, or pantoprazole, 40 mg/day, for 2 weeks according to a randomized protocol. (13)C-Urea breath test was repeated on days 4, 7 and 14 while on therapy and 7 days after proton pump inhibitor withdrawal. RESULTS: Of the patients receiving omeprazole and lansoprazole, 30% (12/40) and 20% (8/41), respectively, became (13)C-urea breath test negative during therapy, compared with none of the 42 patients treated with pantoprazole (P < 0.05). All the false negative (13)C-urea breath test results returned to positive within 1 week of drug withdrawal, with a mean recovery to 84.7 +/- 15.6% of baseline delta(13)CO(2). CONCLUSIONS: Short-term omeprazole and lansoprazole interfere with the 13C-urea breath test, although a return to positive test results invariably occurs within 1 week of proton pump inhibitor withdrawal. In contrast, the accuracy of the (13)C-urea breath test does not appear to be significantly impaired by short