The goals of this study were to investigate the role of a new probiotic preparation, Lactobacillus reuteri Gastrus, (L. reuteri DSM 17938 and L. reuteri ATCC PTA 6475) in treatment of Helicobacter pylori infection.

This was a prospective, double-blind, randomized, placebo-controlled study in 100 H. pylori-positive naïve patients. Lactobacillus reuteri Gastrus (2×10^8 Colony Forming Units) (n=50) or placebo (n=50) were given to the patients throughout the stages of this 3-phase study (pre-eradication, eradication, and follow-up). All patients underwent 13C urea breath test (13C-UBT), blood assessments of gastrin-17 (G17), endoscopy, and the Gastrointestinal Symptom Rating Scale (GSRS). Eradication was confirmed by 13C-UBT 8 weeks after the completion of therapy.

During the pre-eradication period, 13C-UBT [delta] decreased by 13% in Lactobacillus reuteri Gastrus as compared with a 4% increase in placebo (-13.2+/-34% vs. 4.3+/-27%; P<0.03). During eradication, GSRS increased significantly in placebo as compared with Lactobacillus reuteri Gastrus (6.8+/-2.9 vs. 4+/-3.1; P<0.01). Significantly less patients in Lactobacillus reuteri Gastrus, as compared with placebo, reported side effects (40.9% vs. 62.8%; P<0.04). An abnormal G17 value was found in patients receiving placebo compared with Lactobacillus reuteri Gastrus (28% vs. 12%; P<0.02). Eradication rate was 75% in Lactobacillus reuteri Gastrus and 65.9% in placebo (P=NS). Lactobacillus reuteri Gastrus increased eradication rate by 9.1% (odds ratio: 1.5).

Conclusions:
Lactobacillus reuteri Gastrus alone is able to exert an inhibitory effect on H. pylori growth, and when administered with eradication therapy, it led to a significant reduction in antibiotic-associated side effects. Moreover, Lactobacillus reuteri Gastrus was able to decrease serum G17 levels and to (not significantly) increase the H. pylori-eradication rate.