Soru

A 55-year-old man with poorly controlled type 2 diabetes mellitus is evaluated in the hospital on day 4 of admission for a severe diabetic foot infection. He initially presented with a deep, purulent ulcer on the plantar aspect of his right foot surrounded by extensive cellulitis. On admission, empiric therapy was initiated with intravenous vancomycin and piperacillin-tazobactam, and he subsequently underwent surgical debridement of necrotic tissue. Today, his temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $128/78\text{ mm Hg}$, and pulse is $78\text{/min}$. The wound appears clean with developing granulation tissue. Deep tissue cultures obtained during surgery yield heavy growth of Staphylococcus aureus. Antimicrobial susceptibility testing demonstrates resistance to penicillin and susceptibility to oxacillin, cefazolin, and vancomycin. Which of the following is the most appropriate next step in pharmacotherapy?