Effect of proton pump inhibitors on ~(14)C-UBT and emendatory methods

Objective To investigate the effect of proton pump inhibitors on ~14 C_urea breath test (~14 C_UBT) and its emendatory methods. Methods Forty_nine patients who were prospectively evaluated positive for H. Pylori by ~14 C-UBT, were randomized to receive either pantoprazole 40 mg/day or rabeprazole 10 mg/day for 14 days. A repeat breath test was performed on a day 14 to evaluate the ~14 CO_2 DPM.If the patients were negative for HP, they were given a drink of 200 mL containing 4 g citric acid and then determined the ~14 CO_2 DPM by ~14 C-UBT. Results Pantoprazole group and rabaprozole group had negative rates of 25.9%(7/27) and 31.8%(7/22) for HP test. ~14 CO_2 DPM of two groups decreased significantly compared with those before receiving drugs (P0.05), but had no significant difference between two drug groups(P0.05). In 14 patients with nagetive HP, 13/14 cases were HP positive after receivd citric acid, but ~14 CO_2 DPM was still below that before receving medicine (P0.05).Conclusion Proton pump inhibitors significantly affected the accuracy of the UBT and caused false nagetive results but could be emended by recieiving citric acid.