RESUMO
BACKGROUND: Antibiotic associated diarrhea is a major cause of morbidity in hospitalized elderly patients. Probiotics may shorten the duration and reduce the recurrence incidence of this problem. The researchers assessed the protective effects of probiotics in hospitalized patients. PATIENTS AND METHODS: Hospitalized patients aged 18 or older, who were scheduled for antibiotic treatment, were randomly assigned to receive either probiotics or placebo in a double-blind placebo controlled study, within 24 hours from the beginning of antibiotic treatment and for three weeks later. Baseline fecal Clostridium difficile toxin levels (A and B) were obtained within 24 hours of treatment. The patients were monitored for diarrhea, antibiotic treatment and duration of stay. The probiotics were also analyzed for sensitivity to antibiotic treatment in vitro. RESULTS: Forty-two patients completed the study; 21 patients were treated with probiotics and 21 with placebo. Diarrhea occurred in 4 patients (9%): one in the placebo group and three in the probiotic group, p=NS. Clostridium toxin samples were negative in 17 (68%) samples and 8 (23%) were positive (+2 to +4). Diarrhea occurred only in patients treated with wide-spectrum antibiotics, (p = 0.04, Chi2). In-vitro culture of the probiotic capsules yielded gram-positive cocci and bacilli, which were susceptible to many of the antibiotics used by the patients in this study. CONCLUSIONS: There was no significant protecting effect of prophylactic probiotics for antibiotic associated diarrhea in hospitalized patients under antibiotic treatment, mainly because of the susceptibility of the probiotic bacteria to the treatment.