Evaluation of Non-lactose-fermenting Members of the Klebsiella–Enterobacter–Serratia Division: II. Antibiotic Susceptibility

Abstract

Susceptibilities of 303 Serratia and 131 non-lactose-fermenting Klebsiella-Enterobacter organisms to antibiotics were determined by means of the high potency disk diffusion method. Thirteen antibiotics were used, and of these gentamicin was the most effective against Serratia, followed by nalidixic acid, kanamycin, and chloramphenicol. Differences in susceptibilities based on sources of isolation of Serratia strains are presented and discussed. Polymyxin, colistin, and gentamicin were most effective against the Klebsiella-Enterobacter. Most of the Klebsiella-Enterobacter were resistant to ampicillin and cephalothin. Comparisons of antibiotic susceptibility between the Klebsiella-Enterobacter and Serratia and differences based on source of isolation of Serratia are presented and discussed.