Risk factors for nosocomial infective endocarditis in patients with methicillin-resistant Staphylococcus aureus bacteremia

Abstract

Background and objective: Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are increasing. Only a few studies of MRSA infective endocarditis have been conducted, and none have reported its risk factors. We sought to determine the host-related risk factors for infective endocarditis in patients with nosocomial MRSA bacteremia.

Setting: A 2,000-bed, university-affiliated, tertiary-care hospital.

Patients: Thirty-one patients with nosocomial MRSA infective endocarditis between October 1996 and May 2003.

Design: A retrospective chart review was conducted. Data were compared with those from a control group of patients with nosocomial MRSA bacteremia. Logistic regression was used to identify independent risk factors for nosocomial infective endocarditis.

Results: Compared with patients who had nosocomial MRSA bacteremia and no infective endocarditis, patients who had infective endocarditis had a higher incidence of chronic liver disease and a lower incidence of immunodeficiency. The risk of developing infective endocarditis was approximately 10% for patients with nosocomial MRSA bacteremia.

Conclusion: Patients with MRSA bacteremia and underlying chronic liver disease were prone to infective endocarditis.