Influence of cefozopran on intestinal bacterial flora

Cefozopran (CZOP, SCE-2787), a new parenteral cephalosporin antibiotic, was studied for its effect on the intestinal bacterial flora of pediatric patients. The subjects were children admitted for infections (6 males, 4 months to 3 years 2 months old, weight 5.6 to 19.0 kg). CZOP was intravenously administered at a dose from 19.8 to 52.6 mg/kg, 3 to 4 times daily. The feces from these children were collected before, during and after administration, and bacteria were identified and counted. The CZOP concentration, β-lactamase activity and Clostridium difficile D-1 antigen were also assayed, and the MICs of various isolated bacteria were mesured. Changes of bacterial flora in feces during CZOP administration showed some variation. Among aerobic bacteria, 5 of the 6 cases showed a decrease in Enterobacteriaceae, but no significant change was observed in Enterococcus, and as a result, the total count of aerobic bacteria did not show a large change. Regarding anaerobic bacteria, no significant change was observed in Bifidobacterium or Bacteroides, and the total count of anaerobic bacteria did not show a large change. In no case, were glucose non-fermentative Gram-negative bacilli or fungi dominant. Although C.difficile and C. difficile D-1 antigen were detected in 2 and all cases, respectively, there was no clear relationship between the number of C. difficile and the characteristics of the feces. CZOP was detected in fecal samples from 4 cases during and after administration at concentrations ranging from 1.4 to 29.6 μg/g. Drug sensitivities of the bacteria isolated from feces did not change before, during and after the administration of CZOP. The above results suggest that CZOP is a drug with an extremely small influence on the intestinal bacterial flora of children among the new parenteral cephalosporin antibiotics.