Prevalence of colonization with community-associated methicillin-resistant Staphylococcus aureus among end-stage renal disease patients and healthcare workers

Abstract

Objective: To evaluate the prevalence, epidemiologic features, and molecular characteristics of colonization with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) among hospitalized dialysis patients and their healthcare workers (HCWs).

Design: Prospective observational clinical and laboratory study of nasal colonization.

Setting: A 600-bed urban academic medical center.

Subjects: One hundred twenty hospitalized dialysis inpatients and 100 HCWs.

Results: Of 120 patients, 40 (33%) were colonized with S. aureus; 26 (65%) of these 40 were colonized with MRSA. Among the 26 MRSA isolates, 10 (38.5%) carried staphylococcal cassette chromosome (SCC) mec type IV (ie, CA-MRSA), and 7 of these 10 carried the genes for the Panton-Valentine leukocidin (PVL) toxin. Patients colonized with healthcare-associated MRSA strains and those colonized with CA-MRSA strains were similar, except for a higher frequency of a history of congestive heart failure among those with healthcare-associated MRSA strains (P=.014). Among 10 patients who presented with or developed an S. aureus infection while hospitalized, 8 were colonized with S. aureus, 7 with MRSA, and 3 with SCCmec type IV strains. Among 100 HCWs, 31 were colonized with S. aureus, including 6 with MRSA; 2 of the MRSA isolates belonged to CA-MRSA strains, and soft-tissue infections were reported in one of the HCWs and in the family member of the other HCW colonized with these strains.

Conclusions: There is a high rate of colonization with MRSA and CA-MRSA among hospitalized dialysis patients and their HCWs. As other studies have found, it appears that individuals are being colonized with both CA-MRSA strains and healthcare-associated MRSA strains.