A Randomized, Double-blind, Placebo-controlled Pilot Study of Lactobacillus reuteri ATCC 55730 for the Prevention of Antibiotic-associated Diarrhea in Hospitalized Adults

Goals: The purpose of the study was to evaluate Lactobacillus reuteri for the prevention of antibiotic-associated diarrhea (AAD) in hospitalized adults. Background: AAD is a problem in hospitalized adults, contributing to increased length of stay, cost, and mortality. Probiotics have been proposed as a way to prevent AAD. L. reuteri decreases acute infectious diarrhea in children; however, L. reuteri has never been evaluated for the prevention of AAD. Study: In a randomized, double-blind, placebo-controlled pilot study, in-patients receiving antibiotics were given L. reuteri 1 x 10(8) colony-forming units twice daily or an identical placebo for 4 weeks. Stool frequency, consistency, and gastrointestinal symptoms were monitored during the 4-week treatment period and during a 2-week follow-up period. Results: A total of 31 patients were enrolled. Eight patients were excluded in the data analysis because of length of study participation less than 14 days. Mean age was 51 +/- 18 years; 63% were female and 37% male. Most frequent primary diagnosis was pneumonia (20%), followed by abscess (10%), chronic obstructive pulmonary disease (6.7%), and bronchitis (6.7%). Thirteen patients received L. reuteri and 10 received placebo. Patients treated with L. reuteri had a significantly lower frequency of diarrhea compared with placebo (50% in the placebo group vs. 7.7% in the probiotic group, P = 0.02). There were no differences in the frequency or severity of gastrointestinal symptoms. Conclusions: In this placebo-controlled, pilot study, L. reuteri twice daily for 4 weeks significantly decreased AAD among hospitalized adults. L. reuteri was safe and well tolerated.