[Fosfomycin resistance in Staphylococcus saprophyticus and other species of coagulase-negative staphylococci].

Abstract

Susceptibility of 121 isolates of coagulase-negative staphylococci to two antimicrobial agents, novobiocin and fosfomycin, was determined using the agar dilution method. Isolates included 45 strains of Staphylococcus saprophyticus, 26 strains of S. cohnii and S. xylosus, 24 strains of S. epidermidis and 26 strains of S. hominis, S. capitis, S. warneri and S. auricularis . The minimal inhibitory concentration average of fosfomycin for S. saprophyticus differed (p less than 0.001) from that other for novobiocin-resistant staphylococci (S. cohnii and S. xylosus) and for S. epidermidis (p less than 0.001). Out of 45 isolates of S. saprophyticus, 42 were resistant to fosfomycin. The results were very heterogeneous with regard to fosfomycin for all of the other coagulase-negative staphylococci. Resistance to fosfomycin, like resistance to novobiocin, could be used as a presumptive test for the identification of S. saprophyticus.