EFFECT OF CURING HELICOBACTER-PYLORI INFECTION ON INTRAGASTRIC ACIDITY DURING TREATMENT WITH RANITIDINE IN PATIENTS WITH DUODENAL-ULCER

Background-In patients with duodenal ulcer cure of Helicobacter pylori . infection resulted in a pronounced decrease in intragastric pH durin g treatment with omeprazole. Aim-To test the hypothesis that treatment of H pylori adversely affects the pH response to ranitidine. Patients -Eighteen patients with duodenal ulcer who were infected with H pylori were studied. Methods-Twenty four hour pH recordings were performed d uring treatment with ranitidine (300 mg) at night before and four to s ix weeks after cure of H pylori infection. Presence of H pylori was as sessed by a rapid urease test, culture, histology, and a C-13 urea bre ath test. Also, the fasting gastrin concentrations were measured befor e and after treatment for H pylori infection. Results-Cure of H pylori infection resulted in a considerable improvement in both antral and c orpus gastritis and a decrease in fasting gastrin concentrations. As a result of the cure the night time intragastric pH during treatment wi th ranitidine decreased (median pH 6.8 v 5.4; p = 0.007), whereas the acidity during the daytime was not affected, Conclusions-In patients w ith duodenal ulcer the intragastric pH during treatment with ranitidin e depends on H pylori. However, the loss of effectiveness in altering pH seems to be less pronounced than previously found with omeprazole.