[Influence of amoxicillin combined with clavulanic acid on the fecal flora in children].

The effect of an amoxycillin-clavulanic acid combination on the intestinal bacterial ecosystem was studied by differential quantitative analysis of the fecal flora in 11 hospitalized pediatric patients aged 8 months to 4 years. The antibiotic combination was given orally to 7 patients and intravenously to 4. The modifications in the intestinal flora are more important with oral route than intravenous route. After treatment, an increase in ampicillin-resistant E. coli with overgrowth of Klebsiella were found. Our previous studies have shown that this microbial overgrowth carries a risk of secondary septicemia. A strain of amoxycillin-resistant Serratia marcescens emerged but did not pullulate . The other aerobic or anaerobic bacteria were not significantly modified. Most strains which emerged after therapy remained susceptible to the combination. Yeasts emerged in two patients. Thus, the amoxycillin-clavulanic acid combination results in intestinal Klebsiella overgrowth, requiring monitoring of the intestinal bacterial ecosystem.