Emergence of community-associated methicillin-resistant Staphylococcus aureus infection among patients with end-stage renal disease

OBJECTIVE. To evaluate the frequency of infections due to community-associated methicillin-resistant Staphylococcus aureus ( CA-MRSA) strains among our patients with end-stage renal disease. DESIGN. Prospective observational clinical and laboratory study of patients in 2005. Molecular features of isolates recovered from these patients were compared with those of isolates recovered in 2000 from patients with end-stage renal disease. SETTING. A 600-bed urban academic medical center. PATIENTS. Thirty-two patients with end-stage renal disease and MRSA infection at the time of hospitalization from 2005 were evaluated. For comparison, laboratory analysis was performed for 17 MRSA isolates recovered from patients with end-stage renal disease in 2000. RESULTS. The patients from 2005 were more likely than the patients from 2000 to have infection with strains that carried the staphylococcal cassette chromosome ( SCC) mec type IV complex ( 50% vs 11.8%; relative risk, 4.25 [ 95% confidence interval, 1.17-25.98]; P=.012) and the Panton-Valentine leukocidin toxin genes ( 25% vs 0%; P=.038). Eight patients from 2005 were infected with a strain that is identical to MRSA clone USA300 in terms of molecular type and presence of SCCmec type IV and Panton-Valentine leukocidin genes. Among the patients from 2005, those infected with SCCmec type IV strains ( ie, CA-MRSA strains) and those infected with SCCmec type II strains ( ie, healthcare-associated MRSA [ HA-MRSA] strains) were similar with respect to demographic characteristics, risk factors, and outcomes. CONCLUSIONS. We documented an increased proportion of infections with CA-MRSA strains, including clone USA300, among our population of patients undergoing dialysis. Patients infected with CA-MRSA strains and HA-MRSA strains were similar with respect to presenting illness and outcomes.