Efficacy of compoundLactobacillus acidophilustablets combined with quadruple therapy forHelicobacter pylorieradication and its correlation with pH value in the stomach: a study protocol of a randomised, assessor-blinded, single-centre study

Helicobacter pylori (Hp) is an important pathogenic factor for chronic gastritis, peptic ulcer, gastric cancer, gastric mucosa-associated lymphoid tissue lymphoma and other diseases. In China, the Hp infection rate is high, but the eradication rate is decreasing. A large number of literatures have shown that the addition of Lactobacillus acidophilus can improve the Hp eradication rate and reduce the side effects of antibiotic treatments. At present, the exact mechanism and curative effect of L. acidophilus in the eradication of Hp have not yet been determined, and the conclusions obtained from relevant meta-analyses at home and abroad are different. Thus, it is very necessary and urgent to further complete a high-quality, clinical, randomised controlled trial research. If this study is successful, it can provide a new idea and a plan for Hp eradication therapy.This study is a prospective, randomised controlled, single-blinded, parallel-design trial. We will randomly assign 526 adult patients (≥18 years but <70 years) with Hp confirmed positive by the kit for 14C-urea breath test. Eligible subjects were randomly divided into two groups (group A and group B), with 263 subjects in each group. Group A is a quadruple therapy group, while group B is an L. acidophilus tablets combined with quadruple therapy group. All patients were examined by gastroscopy, and 50 patients in each group will be placed under gastric pH monitor. The Hp eradication rate is the primary outcome. The secondary outcomes include gastric pH situation and adverse drug reactions.The study protocol has been approved by the Clinical Research Ethics Committees of Chongqing University Cancer Hospital and Chongqing Cancer Hospital (2018[012]). The results from this trial will be submitted for publication in peer-reviewed journals and will be presented at national and international conferences.ChiCTR17014185; Pre-results.