Multidrug-Resistant MRSA Clone Found in Male Homosexuals
Multidrug-resistant USA300 infections often found in anogenital area; may be sexually transmitted
TUESDAY, Jan. 15 (HealthDay News) -- Infection with a multidrug-resistant clone of methicillin-resistant Staphylococcus aureus (MRSA) is becoming an important source of disease among men who have sex with men in San Francisco and Boston, according to research published online Jan. 15 in advance of publication in the Feb. 19 print issue of the Annals of Internal Medicine.
Binh An Diep, Ph.D., of the University of California San Francisco, and colleagues conducted a population-based survey of nine medical centers in San Francisco. They also conducted cross-sectional studies in outpatient clinics in San Francisco and Boston. The goal was to estimate the incidence and spatial clustering of the multidrug-resistant MRSA clone USA300 and determine risk factors for infection.
The overall incidence of infection in San Francisco was 26 cases per 100,000 people, with an incidence higher in eight ZIP codes with a higher proportion of same-sex male couples. In the San Francisco-based clinic study, the investigators found that multidrug-resistant USA300 often resulted in infections of the buttocks, genitals or perineum. In Boston, the infection was found only in men who have sex with men.
"Several important antimicrobial classes for treatment of MRSA infections or eradication of colonization, including clindamycin, tetracycline and mupirocin, may not be effective in this population. Resistance to trimethoprim-sulfamethoxazole and rifampin remains rare among USA300 isolates and was not seen in multidrug-resistant USA300 in our study," the authors write.
Pfizer provided an unrestricted grant to a co-author to help fund the study.