History of antibiotic treatment and prevalence of H. pylori infection among children: results of a population-based study.

We investigated the association of commonly prescribed antibiotics with the prevalence of current Helicobacter pylori infection among children. All children who were screened in 1996 for school fitness by physicians of the Public Health Service in Ulm, a city in the south of Germany, were invited to participate in the study. Infection status was determined by 13C-urea breath test. In addition, the parents of the children were asked to fill out a standardized questionnaire. Nine hundred forty-five out of the 1201 eligible children participated in the study (response rate = 79%). The children were aged 5 to 8 years. Seventeen children who were receiving antibiotics at the day of the breath test were excluded from the analysis. Overall, for 683 children (73.6%) a prior usage of antibiotics was reported. Prevalence of H. pylori infection was significantly lower in children with reported antibiotic usage (odds ratio = 0.46; 95% CI, 0.27-0.76 after adjustment for confounders). Our results suggest that information on prior usage of antibiotics should always be considered in studies evaluating prevalence and risk factors of H. pylori infection in children.