The Effects of Multistrain Probiotic Compound on Bismuth-Containing Quadruple Therapy for Helicobacter pylori Infection: A Randomized Placebo-Controlled Triple-Blind Study

Background Evidence has shown benefits of single-strain probiotics for Helicobacter pylori eradication. We investigated the effects of adding a multistrain probiotic compound on bismuth-containing quadruple therapy for H.pylori infection. Materials and Methods Adult patients with peptic ulcer disease and confirmed H.pylori infection (n=180) were randomized to receive bismuth-containing quadruple therapy (omeprazole, bismuth subcitrate, amoxicillin, and clarithromycin) plus a probiotic compound or placebo for 2weeks. The probiotic compound contained seven bacterial species including Lactobacillus and Bifidobacterium strains and Streptococcus thermophiles. Eradication of H.pylori was assessed 4weeks after medication by 13C urea breath test. Other outcomes were dyspepsia symptoms, therapy-related adverse effects, and patient's tolerance. Results Eighty-four patients in the probiotic and 86 in the placebo group completed the trial. With per-protocol (intention to treat) analysis, H.pylori was eradicated in 82.1% (76.6%) of the probiotic and 84.8% (81.1%) of the placebo group, p=.392 (0.292). Symptoms were significantly improved with similar trends in both groups. Regarding the adverse effects, diarrhea was less frequent (2.2 vs 11.1%, p=.016), while abdominal pain was more frequent (10 vs 2.2%, p=.029) in the probiotic group. The two groups were similar in treatment tolerance (p=.851). Conclusions In overall, our studied multistrain probiotic compound has not beneficial effects in the treatment of H.pylori infection. It might be related to the low dosage of our probiotic regimen and/or high frequency of upper gastrointestinal adverse effects which in turn could decrease the eradication efficacy.