The effect of Helicobacter pylori retreatment with ranitidine bismuth citrate, clarithromycin, and metronidazole depends on the first-line therapy

Background: Helicobacter pylori eradication rates seem to decrease. This study evaluates the effect of retreatment with ranitidine bismuth citrate (RBC) 400 mg B.I.D., clarithromycin (C) 500 mg B.I.D., and metronidazole (M) 500 mg every morning and 1,000 mg every evening for 14 days [RBC.C.M]. Study: Nine gastroenterologic units included patients with unsuccessful eradication of H. pylori in a preceding randomized trial. Previous treatment was either omeprazole (O) 20 mg, C 250 mg, and M 500 mg [O.C.M] or RBC 400 mg, tetracycline (T) 1,000 mg, and M 500 mg [RBC.T.M]; all,drugs were given twice daily for 7 days. Results: Twenty-six H. pylori-positive patients were included (nine males, 17 females; mean age, 54 years; range, 39-74 years). The eradication rates in the groups previously treated with O-C-M and RBC.T.M were three of nine (33%) (95% CI = 12-65) and 15 of 17 (88%) (95% CI = 66-97) respectively (p = 0.008). The corresponding results in a "per-protocol" analysis were three of eight (38%) (95% CI = 13-69) and 10 of 10 (100%) (95% CI = 72-100), respectively (p = 0.007). A side effect score was 21.8 compared with 8.3 in the previous study (p < 0.001). Conclusions: The effect of a retreatment regimen depends on the preceding treatment. The RBC.C.M regimen is effective in nonresponders to RBC.T.M, but it seems unsuitable after failure of the O.C.M regimen.