Rapid Clearance of Refractory Methicillin-Resistant Staphylococcus aureus (MRSA) Bacteremia With Septic Pulmonary...

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is associated with significant morbidity and mortality, particularly when persistent despite appropriate therapy. Refractory bacteremia often reflects inadequate source control, metastatic infection, or antimicrobial treatment failure and requires timely reassessment and escalation of care. We report the case of a 44-year-old male patient with poorly controlled type 2 diabetes mellitus and polysubstance use who presented with altered mental status and was found to have diabetic ketoacidosis, necrotizing soft tissue infection of the right lower extremity, and MRSA bacteremia. His hospital course was complicated by septic pulmonary emboli and lung abscesses. Despite prompt initiation of intravenous vancomycin, therapeutic drug levels, and definitive surgical source control via below-knee amputation, surveillance blood cultures remained persistently positive for MRSA. Following multidisciplinary evaluation, vancomycin was discontinued and intravenous ceftaroline was initiated, resulting in rapid clearance of bacteremia and sustained clinical improvement. The patient was discharged to a skilled nursing facility to complete a six-week course of ceftaroline, with no evidence of recurrent infection on follow-up. This case underscores the importance of early recognition of vancomycin failure in persistent MRSA bacteremia and highlights the role of ceftaroline as an effective salvage therapy, particularly in patients with metastatic infection and high-risk comorbidities. Multidisciplinary management and individualized antimicrobial strategies remain critical for achieving favorable outcomes in refractory MRSA infections.