Mechanisms of fosfomycin resistance in carbapenem-resistant Enterobacter sp

•We report the prevalence of fosfomycin–resistance genes among blaKPC-producing Enterobacter in the Southeastern US.•Fosfomycin susceptibility was 50% (4 of 8) by CLSI and 25% (2 of 8) by EUCAST in the fosA–positive strains.•Fosfomycin–resistance genes were found in organisms within a broad range of MICs.•Resistance genes were found in CLSI- and EUCAST-susceptible strains. We report on fosfomycin susceptibility and mechanisms of resistance in clinical strains of blaKPC-positive Enterobacter sp. (n = 19). A total of 14 strains (74%) were susceptible to fosfomycin; 8 strains (42%) were positive for fosA and no strains were positive for FosA3 or FosC2. FosA presence does not appear to correlate with susceptibility.