Coyhaique

Researchers are studying Helicobacter pylori infection, the main cause of gastric cancer, in adolescents aged 14-18 years in three regions of Chile. The trial aims to evaluate a "screen and treat" approach to eradicate H. pylori infection in asymptomatic teenagers, assessing its effectiveness and impact on clinical outcomes, serum biomarkers of gastric damage, and the gut microbiome. This research builds on previous findings showing high infection rates acquired early in childhood, with low spontaneous eradication and potential long-term gastric damage if untreated. The study involves screening up to 1000 adolescents with the Urea Breath Test (UBT) to identify persistent H. pylori infection confirmed by at least two positive tests over three months. Persistently infected participants will be randomized in a 2:1 ratio to receive either a 14-day antimicrobial treatment regimen (7 days of lansoprazole and amoxicillin followed by 7 days of lansoprazole, clarithromycin, and metronidazole) or no treatment. A subset of 60 non-infected adolescents will be observed as controls. Participants who remain untreated after six months will be offered eradication therapy. During the trial, adolescents will undergo multiple evaluations including UBT at baseline, one month post-treatment, and every six months thereafter, along with gastroenterological exams, blood samples for gastric damage biomarkers, and stool samples to assess gut microbiota and antimicrobial resistance. The primary outcomes include changes in infection status, gastric disease indicators, and biomarker levels up to six months post-treatment. The study also monitors antimicrobial resistance and gut microbiome changes over 2-3 years, with safety and reinfection rates tracked throughout follow-up.