title: Systematic review and meta-analysis: Multi-strain probiotics as adjunct therapy for Helicobacter pylori eradication and prevention of adverse events.
abstract: BACKGROUND
  Eradication rates with triple therapy for Helicobacter pylori infections have currently declined to unacceptable levels worldwide. Newer quadruple therapies are burdened with a high rate of adverse events. Whether multi-strain probiotics can improve eradication rates or diminish adverse events remains uncertain.
  
  
  METHODS
  Relevant publications in which patients with H. pylori infections were randomized to a multi-strain probiotic or control were identified in PubMed, Cochrane Databases, and other sources from 1 January 1960-3 June 2015. Primary outcomes included eradication rates, incidence of any adverse event and the incidence of antibiotic-associated diarrhea. As probiotic efficacy is strain-specific, pooled relative risks and 95% confidence intervals were calculated using meta-analysis stratified by similar multi-strain probiotic mixtures.
  
  
  RESULTS
  A total of 19 randomized controlled trials (20 treatment arms, n = 2730) assessing one of six mixtures of strains of probiotics were included. Four multi-strain probiotics significantly improved H. pylori eradication rates, five significantly prevented any adverse reactions and three significantly reduced antibiotic-associated diarrhea. Only two probiotic mixtures (Lactobacillus acidophilus/Bifidobacterium animalis and an eight-strain mixture) had significant efficacy for all three outcomes.
  
  
  CONCLUSIONS
  Our meta-analysis found adjunctive use of some multi-strain probiotics may improve H. pylori eradication rates and prevent the development of adverse events and antibiotic-associated diarrhea, but not all mixtures were effective.
authors.affiliation: Department of Medicinal Chemistry, University of Washington, Seattle, USA.
authors.forename: Lynne V
authors.initials: LV
authors.lastname: McFarland
authors.affiliation: Division of Gastroenterology, Children's Hospital of Fudan University, Shanghai, P.R. China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Division of Gastroenterology, Children's Hospital of Fudan University, Shanghai, P.R. China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Universitatsklinikum Magdeburg AOR, Magdeburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Malfertheiner
keywords: Helicobacter pylori; Probiotics; adverse events; diarrhea; meta-analysis