Community-associated MRSA (CA-MRSA): an emerging pathogen in infective endocarditis

Over the last decade, a novel methicillin-resistant Staphylococcus aureus (MRSA) has emerged, primarily associated with healthy individuals within the community. This organism is distinct from healthcare-associated MRSA (HA-MRSA) in terms of epidemiology, microbiology and clinical manifestation and as such has been defined as community-associated MRSA (CA-MRSA). Given that S. aureus is a major aetiological agent of infective endocarditis (IE), particularly associated with the iv drug user population, reports of IE attributed to CA-MRSA are now emerging in the literature. The aims of this article are to (i) define and contrast CA-MRSA with HA-MRSA; (ii) review the published cases of CA-MRSA IE to date; and (iii) evaluate the current international recommendations for antibiotic prophylaxis and treatment regimens for IE in relation to CA-MRSA.