In vitro activity of daptomycin against strains isolated from diabetic foot ulcers

The aim of this study was to evaluate the in vitro activity of daptomycin and other comparator agents against bacterial strains isolated from diabetic foot infections (DFI). All diabetic patients hospitalized for a first episode of DFI (stage 2 to 4, according to the International Working Group of Diabetic Foot classification) were selected in Nîmes University hospital between June 2006 to August 2007. MIC were determined using E-test strip (AB Biodisk) and custom broth microdilution panels against bacterial strains isolated from foot samples. Two hundred strains were studied. Daptomycin was active against 99.5% of all the strains especially Streptococcus sp. (100%), Enterococcus sp. (100%), coagulase-negative Staphylococcus (100%) and methicillin-susceptible Staphylococcus aureus (100%). Exclusively, one methicillin-resistant S. aureus strain was not covered by this antibiotic. Daptomycin, a new broad spectrum antimicrobial agent against Gram-positive cocci, is qualified to belong to the therapeutic arsenal package of complicated skin and soft tissue infections in diabetic patients after microbial documentation.