[Multicenter evaluation of the antimicrobial activity in vitro for six broad-spectrum beta-lactams in China using the E-test method].

OBJECTIVE: To investigate the in vitro activities of cefepime and other 5 beta-lactam antimicrobial agents against 937 strains isolated from 10 teaching hospitals in different geographical areas in China during the early 1998. METHODS: The MIC values of cefepime, ceftazidime, ceftriaxone, imipenem, cefoperazone/sulbactum, and piperacillin against 937 isolates were tested by a gradient concentration method (E-test((R)); AB Biodisk Co.). RESULTS: Quality control isolates were tested in all working processes. MIC values of 96.5% (829/859 times) of quality assurance tests were within expected ranges of NCCLS. Only imipenem and cefepime could inhibit 90% of enterobacter and citrobacter strains, Cefepime were significantly more active than 3rd Generation cephalosporins in enterobacter and citrobacter strains, and little better active than E. coli and Klebsiella spp. (98%, 95% susceptibility). All tested antimicrobial excluding ceftazidime had very high activity to oxacillin susceptible Staphylococci (95% approximately 100% susceptibility). cefepime, ceftazidime, imipenem, and cefoperazone/sulbactum had similar activity to Pseudomonas aeruginosa (83% approximately 79% susceptibility). Both imipenem and cefoperazone/ sulbactum were very active to Acinetobacter spp. (97%, 89% susceptibility). CONCLUSION: The rank order of activity of the six tested agents is imipenem (97% Susceptible) > cefepime (89%) > cefoperazone/sulbactum (86%) > ceftazidime (76%) > ceftraixone (67%) > piperacillin (57%). The data are helpful to guide empiric therapy with beta-lactams in China.