Synergistic activity of fosfomycin and chloramphenicol against vancomycin-resistant Enterococcus faecium (VREfm) isolates from bloodstream infections

Vancomycin-resistant Enterococcus faecium (VREfm) infections are increasing. Current anti-VREfm options (linezolid and daptomycin) suboptimal. Fosfomycin maintains good efficacy against VREfm chloramphenicol is active ≥ 90% of VREfm. We tested + fosfomycin (CAF+FOS) 10 isolated from blood. MICs were 64 to 512 µg/mL for 8 16 chloramphenicol. The combination decreased both MICs, with a synergic effect in 50% the isolates an additive remaining 50%. Time-kill assays performed on fractional inhibitory concentration index ≤ 0.5 strains confirmed synergism. antibiotic at ¼ minimum concentrations (MICs) caused 2 log10 reduction compared two antibiotics alone. Finally, we provided proof concept vitro CAF+FOS G. mellonella. survival mellonella larvae treated was significantly higher. activity increases when they used combination.