The current European guidelines (Maastricht VI/Florence consensus report) on the management of Helicobacter pylori infection1 recommend population-based H. pylori screening programmes for asymptomatic individuals in the general population to eradicate the microorganism for gastric cancer prevention. However, this is expected to result in a considerable increase in antibiotic use2 as half of the global population are estimated to be infected.3 Therefore, the guidelines suggest that caution is required in choosing the appropriate antibiotics to minimise antimicrobial resistance.1

The importance of gut resistome induction following H. pylori eradication therapies has been debated for years, and the available information is controversial; the general thought is that normal gut microbiota is restored 3–6 months after antibiotic treatment.4

Therefore, we conducted a randomised controlled clinical trial as part of the GISTAR study5 in Latvia by evaluating alterations in gut microbiota before and 6 months after administering two treatment regimens for H. pylori eradication. Stool samples were collected from 158 patients, of whom 27 received high-dose amoxicillin/bismuth therapy, including bismuth subcitrate 240 mg two times per day, amoxicillin 1000 mg three times per day, and esomeprazole 40 mg two times per day for 14 days, and 31 received clarithromycin 500 mg, amoxicillin 1000 mg and esomeprazole 40 mg, all two times per day for 14 days. The control group, which included 50 subjects, did not receive any treatment. The participants’ median age …