Increasing enterobacter bacteremia in pediatric patients

Thirty-two episodes of Enterobacter bacteremia were identified in 30 patients at Children's Hospital of Michigan between September, 1989, and November, 1992. Fifty-six percent of the episodes were nosocomial. Enterobacter accounted for 14% of all nosocomial bacteremias and was the most common Gram-negative organism causing such infections. Enterobacter cloacae was the most commonly isolated species (72%). Twenty-nine (97%) patients had underlying risk factors for infection, including central venous catheters in 22. The susceptibility pattern of 46 Enterobacter isolates from blood during the same study period showed high resistance to extended spectrum penicillins and third generation cephalosporins but low resistance to aminoglycosides and trimethoprim-sulfamethoxazole (TMP/SMX). Resistance to third generation cephalosporins increased throughout the study period and was higher in patients who had received these agents during the previous month. In situations where there is a high frequency of Gram-negative bacteremias with organisms resistant to third generation cephalosporins, we suggest that initial therapy be a combination of a beta-lactam agent and an aminoglycoside or TMP/SMX.