Daptomycin-nonsusceptible vancomycin-intermediate staphylococcus aureus vertebral osteomyelitis cases complicated by bacteremia treated with high-dose daptomycin and trimethoprim-sulfamethoxazole

We report two cases of daptomycin (DAP)-nonsusceptible (DNS) vancomycin-intermediate Staphylococcus aureus (VISA) vertebral osteomyelitis cases complicated by bacteremia treated with high-dose daptomycin and trimethoprim-sulfamethoxazole. Both patients responded rapidly and favorably to this combination. The clinical isolates from the two patients were tested post hoc in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model to confirm the bactericidal activity and enhancement of daptomycin and trimethoprim- sulfamethoxazole. The combination of high-dose daptomycin and trimethoprim-sulfamethoxa-zole should be explored further for the treatment of DNS VISA strains.