Effect of the ingestion of a dietary product containing Lactobacillus johnsonii La1 on Helicobacter pylori colonization in children

Dietary components such as vegetable or probiotic microorganisms have been proposed as an alternative solution to decrease Helicobacter pylori colonization in at-risk populations. Some strains of lactic acid bacteria have been shown to exert bacteriostatic or bactericidal effects against H. pylori in in vitro and in vivo models of infection by this pathogen. We investigated whether regular ingestion of a dietary product containing Lactobacillus johnsonii La1 or L. paracasei ST11 would interfere with H. pylori colonization in children.A double blind, randomized, controlled clinical trial was carried out in school children from a low socioeconomic area of Santiago. Subjects were 326 asymptomatic children (9.7 +/- 2.6 y) screened for H. pylori by the (13)C-urea breath test; H. pylori-colonized subjects were distributed into five groups to receive a product containing live La1 or ST11 (groups 1 and 3), heat-killed La1 or ST11 (groups 2 and 4), or vehicle (group 5) everyday for 4 wk. A second (13)C-urea breath test was carried out at the end of this period. Differences in delta(13)CO(2) above baseline values before (DOB1) and after (DOB2) probiotic treatment were evaluated.A high prevalence of H. pylori colonization, 77.3%, was observed in our population. A moderate but significant difference (DOB2 - DOB1) was detected in children receiving live La1 (-7.64 per thousand; 95% confidence interval, -14.23 to -1.03), whereas no differences were observed in the other groups. The magnitude of the decrease in DOB values induced by La1 ingestion correlated with the basal values of DOB before treatment (r = 0.48, P = 0.0074).Regular ingestion of a product containing Lactobacillus La1 may represent an interesting alternative to modulate H. pylori colonization in children infected by this pathogen.