Methicillin-resistant Staphylococcus aureus colonization, behavioral risk factors, and skin and soft-tissue infection at an ambulatory clinic serving a large population of HIV-infected men who have sex with men.

We conducted a prospective cohort study of 795 outpatients, many of whom were human immunodeficiency virus-infected men who have sex with men, to characterize risk of skin and soft-tissue infection (SSTI) associated with methicillin-resistant Staphylococcus aureus (MRSA) nares and perianal colonization. Multivariate analysis revealed that perianal colonization, drug use, and prior SSTIs were strongly associated with development of an SSTI. Of the patients who were colonized with MRSA at study entry, 36.7% developed an SSTI during the ensuing 12 months, compared with 8.1% of persons who were not colonized with MRSA.