Five cases of bacterial endocarditis after furunculosis and the ongoing saga of community-acquired methicillin-resistant Staphylococcus aureus infections

Abstract

Bacterial endocarditis secondary to Panton-Valentine leukocidin producing community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections is rare. We report 5 previously healthy patients who presented with endocarditis after developing furunculosis due to CA-MRSA. A retrospective chart review of all patients with MRSA positive blood cultures was conducted over a 12-month period. Patients with multiple positive blood cultures within 72 h of admission and who had no risk factors for MRSA acquisition were included. Modified Duke's criteria were used to define bacterial endocarditis. PCR detection of Panton-Valentine leukocidin (PVL) genes as well as SCCmec typing was performed. In addition, strain typing of MRSA isolates was performed utilizing pulsed-field gel electrophoresis. Five out of a total of 193 patients had features consistent with CA-MRSA infections and met modified Duke's criteria for bacterial endocarditis. Blood culture isolates were found to be PVL gene positive and carried the type IV SCCmec element. PFGE confirmed that skin isolate was identical to the isolate cultured from his blood. Bacterial endocarditis in patients with CA-MRSA furunculosis is an emerging entity. In areas where CA-MRSA skin infections are prevalent, inappropriate initial antibiotics remain a major problem and may result in significant morbidity.