Influence of a probiotic mixture on antibiotic induced microbiota disturbances.

Abstract

To study the effect of probiotic consumption on the faecal microbiota during and after antibiotic exposure. A randomized, double-blind, placebo-controlled, parallel group study with a two species probiotic combination [Lactobacillus acidophilus (L. acidophilus) ATCC 700396 and Bifidobacterium lactis (B. lactis) ATCC SD5220] on healthy adults during and after antibiotic treatment (amoxicillin 875 and 125 mg clavulanate). The dominant faecal microbiota was studied by real time-polymerase chain reaction to determine if this probiotic preparation could facilitate restoring the microbiota to its pre-antibiotic state and influence the prevalence of beta-lactam resistance. Gastrointestinal symptoms were recorded by questionnaire and Bristol stool scale. Subjects on the probiotic combination had significantly higher faecal counts of L. acidophilus ATCC 700396 and B. lactis at day 8 (end of antibiotic treatment period) vs those on placebo. Furthermore, subjects on the probiotic combination had significantly higher faecal counts of L. acidophilus ATCC 700396 and B. lactis at Day 15 (end of probiotic treatment) vs those on placebo. Lactobacillus counts remained stable in the probiotic group over the course of the study, while Clostridium XIV group was higher at the end of the study and closer to baseline levels; this in contrast to the placebo group. Beta-lactam resistance in creased after antibiotic exposure and was not different between both treatment groups. Gastrointestinal symptoms were generally mild and did not differ between the treatment groups, which correlates with the generally small changes in the microbiota. Consumption of the probiotic combination mainly leads to an increase in the faecal levels of the species included in the preparation.