In vitro antibacterial activity of cefminox

Objective To evaluate the in vitro activity of cefminox against gram-negative and anaerobic clinical isolates.Methods The minimum inhibitory concentrations(MICs) of cefminox against 884 strains of bacterial isolates recently collected from clinical setting.Results were analyzed according to CLSI 2012 breakpoints.Results Of the 316 E.coli and K.pneumoniae strains tested,96(30.4%) produced neither ESBLs nor AmpC,173(54.7%) produced ESBLs,6(1.9%) produced AmpC,and 41(13.0%) produced both ESBLs and AmpC.Cefminox showed excellent antibacterial activity against both ESBLs-positive and ESBLs-negative E.coli and K.pneumoniae strains,Proteus spp.and Morganella spp.The MIC50 and MIC90 values were mostly less than 2 mg/L.Cefminox demonstrated better antimicrobial activity than that of cefmetazole and cefoxitin.The activity of cefminox was higher than cefathiamidine and cefuroxime,cefoperazone-sulbactam and piperacillin-tazobactam against the E.coli and K.pneumoniae strains without ESBLs or AmpC,but lower than carbapenems against ESBLs-producers and AmpC-producers of E.coli and K.pneumoniae,and other Enterobacteriaceae bacteria.The activity of cefminox was poor against AmpC-producing E.coli and K.pneumoniae,Enterobacter,Serratia spp.,Citrobacter spp.,P.aeruginosa or A.baumannii.However,cefminox was highly active against Fusobacterium spp.,showing MIC50 ≤0.06 mg/L and MIC90=1 mg/L.Cefminox also showed good antimicrobial activity against other anaerobes.Conclusions Cefminox has broad-spectrum antimicmbial activity against both ESBLs-positive and ESBLs-negative E.coli and K.pneumoniae strains,Proteus spp.,Morganella spp.and anaerobic clinical isolates.These results indicate that cefminox is the appropriate choice for treatment of infections caused by such cefminox-sensitive isolates.