Evaluation of the in vitro antimicrobial activity of cefepime compared to other broad-spectrum beta-lactams tested against recent clinical isolates from 10 Chinese hospitals. Chinese Antimicrobial Resistance Study Group.

A surveillance study was initiated in China in 1998 in which 10 medical centers participated. The susceptibility profiles of 996 commonly occurring pathogens belonging to 10 different species groups were tested by the Etest (AB BIODISK, Solna, Sweden) against six broad-spectrum beta-lactam antimicrobial agents (cefepime, ceftazidime, ceftriaxone, imipenem, cefoperazone/sulbactam and piperacillin or oxacillin). Quality control was closely monitored and cefepime- and/or imipenem-resistant Enterobacteriaceae were referred to the reference laboratory (University of Iowa College of Medicine, Iowa City, IA) for confirmation. The isolates of Citrobacter spp. and Enterobacter spp. were generally inhibited by imipenem (100% susceptible) and cefepime (89-94%), but were more resistant to the other drugs tested (< or = 74% susceptible). The indole-positive Proteus spp. and Serratia spp. isolates were > 94% susceptible to all tested beta-lactams except piperacillin. Organisms capable of producing extended spectrum beta-lactamases (ESBLs), which included Klebsiella spp. and Escherichia coli, were most susceptible to imipenem (100%) and cefepime (> 90%). Among the non-enteric Gram-negative bacilli, all drugs were marginally active against Pseudomonas aeruginosa (MIC90s, 32-> 256 ug/mL) and the Acinetobacter spp. were rather resistant to all the compounds, except imipenem (96% susceptible). All strains of Staphylococcus spp. were susceptible to the tested antimicrobials except for ceftazidime, which had a low potency (MIC90, 12-16 micrograms/mL) against Chinese isolates with MICs that fell into the intermediate category. Cefepime, the fourth-generation cephalosporin, showed a very broad spectrum of activity against Gram-negative pathogens as well as oxacillin-susceptible Staphylococcus spp. that was comparable with imipenem (widest spectrum) and superior to the other tested beta-lactams overall. Continued monitoring of clinical strains in China seems necessary to guide chemotherapy.