Prevalence and risk factors for methicillin-resistant Staphylococcus aureus in an HIV-positive cohort.

BACKGROUND

Persons living with HIV (PLWH) are disproportionately burdened with methicillin-resistant Staphylococcus aureus (MRSA). Our objective was to evaluate prevalence and risks for MRSA colonization in PLWH.

METHODS

Adults were recruited from Johns Hopkins University AIDS Service in Baltimore, Maryland. A risk questionnaire and specimen collection from anatomic sites with culture susceptibility and genotyping were completed. Generalized estimating equation modeling identified MRSA colonization risk factors.

RESULTS

Of 500 participants, most were black (69%), on antiretroviral therapy (ART) (87%), with undetectable viral loads (73.4%). Median CD4 count was 487 cells/mm(3) (interquartile range, 316-676.5 cells/mm(3)). MRSA prevalence was 15.4%, predominantly from the nares (59.7%). Forty percent were nares negative but were colonized elsewhere. Lower odds for colonization were associated with recent sexual activity (adjusted odds ratio [AOR] = 0.84, P < .001) and ART (AOR = 0.85, P = .011). Increased odds were associated with lower income (<$25,000 vs >$75,000; AOR = 2.68, P < .001), recent hospitalization (AOR = 1.54, P < .001), incarceration (AOR = 1.55, P < .001), use of street drugs (AOR = 1.43, P < .001), and skin abscess (AOR = 1.19, P < .001).

CONCLUSIONS

Even with high MRSA prevalence, the proportion identified through nares surveillance alone was low, indicating the importance of screening multiple anatomic sites. Associations were not found with same-sex coupling or black race. MRSA prevention might be a benefit of ART in PLWH.