Novel Combinations of Vancomycin plus Ceftaroline or Oxacillin against Methicillin-Resistant Vancomycin-Intermediate Staphylococcus aureus (VISA) and Heterogeneous VISA

Evaluation of Vancomycin in Combination with Piperacillin-Tazobactam or Oxacillin against Clinical Methicillin-Resistant Staphylococcus aureus Isolates and Vancomycin-Intermediate S. aureus Isolates In Vitro

“…Previous in vitro studies have examined the effects of antistaphylococcal ␤-lactam (ASBL) antibiotics on VAN antimicrobial activity against MRSA and VISA isolates (15)(16)(17)(18)(19)(20)(21). Those studies showed that the activity of VAN against MRSA is enhanced by the addition of ASBLs but did not elucidate a mechanism to explain the synergistic interaction between these ASBLs and VAN against MRSA.…”

Evaluation of Ceftaroline, Vancomycin, Daptomycin, or Ceftaroline plus Daptomycin against Daptomycin-Nonsusceptible Methicillin-Resistant Staphylococcus aureus in an In Vitro Pharmacokinetic/Pharmacodynamic Model of Simulated Endocardial Vegetations

“…Unfortunately, as the MIC for VAN increases, the DAP MIC may also increase (2)(3)(4). DAP-nonsusceptible (DNS) MRSA, defined as a DAP MIC of Ͼ1 mg/liter, have now been reported (5)(6)(7)(8)(9).…”

Ceftaroline-Resistant, Daptomycin-Tolerant, and Heterogeneous Vancomycin-Intermediate Methicillin-Resistant Staphylococcus aureus Causing Infective Endocarditis

“…Thus, additional CPT resistance significantly limited the therapeutic options. Despite the resistance phenotypes, we decided to use the combination of DAP plus CPT, taking theoretical advantage of the "seesaw" effect (10,11). This rationale was strongly supported by our time-kill studies, which showed synergism using concentrations of antibiotics achievable by standard human dosing of both DAP and CPT.…”