Effect of pretreatment with Lactobacillus gasseri OLL2716 on first-line Helicobacter pylori eradication therapy

Background and Aim: Helicobacter pylori eradication clearly decreases peptic ulcer recurrence rates. H. pylori eradication is achieved in 70-90% of cases, but treatment failures due to poor patient compliance and resistant organisms do occur. Lactobacillus gasseri can suppress both clarithromycin-susceptible and -resistant strains of H. pylori in vitro. The aim of this study was to determine the effect of pretreatment with L. gasseri- containing yogurt on H. pylori eradication. We conducted a randomized, controlled clinical trial in patients with H. pylori infection. Methods: A total of 229 patients were randomized into either a 1-week triple therapy of rabeprazole (10mg bid), amoxicillin (750mg bid), and clarithromycin (200mg bid) or triple therapy plus L. gasseri-containing yogurt. In the yogurt-plus-triple therapy groups, yogurt containing L. gasseri OLL2716 (112g) was given twice daily for 4weeks (3weeks pretreatment and also 1week during eradication therapy). Clarithromycin resistance was determined by the detection of a mutation in 23S rRNA using nested polymerase chain reaction and the direct sequencing of DNA from pretreatment feces. H. pylori eradication was diagnosed based on the urea breath test and a stool antigen test after 8weeks of eradication. Results: The status of H. pylori susceptibility to clarithromycin was successively determined in 188 out of 229 samples. The rate of infection with clarithromycin-resistant strains of H. pylori was 27.1%. Overall eradication (intention to treat/per protocol) was 69.3/74.5% for the triple-only group, and 82.6/85.6% for the yogurt-plus-triple group (P=0.018/P=0.041). Eradication of primary clarithromycin-resistant strains tended to be higher for yogurt-plus-triple therapy than triple-only therapy (38.5 vs 28.0%, respectively, P=0.458). Conclusion: This study confirmed that the major cause of treatment failure is resistance to clarithromycin. A 4-week treatment with L. gasseri-containing yogurt improves the efficacy of triple therapy in patients with H. pylori infection.