Routine screening for methicillin-resistant Staphylococcus aureus among patients newly admitted to an acute rehabilitation unit

BACKGROUND: Following an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infection in our acute rehabilitation unit in 1987, all patients except in-house transfers (because of their low prevalence of MRSA colonization) underwent MRSA screening cultures on admission. OBJECTIVES: To better characterize the current profile of patients with positive MRSA screening cultures at the time of admission to our acute rehabilitation unit, and to determine the relative yield of nares, perianal, and wound screening cultures in this population. METHODS: Prospective chart review with ongoing active surveillance for infections associated with the acute rehabilitation unit. RESULTS: The rate of MRSA isolation from one or more body sites increased significantly from 5% (1987-1988) to 12% (1999-2000) (P=.0009) for newly admitted patients and from 0% to 796 (P<.0001) for in-house transfers. A negative nares culture was highly predictive (98%) of a negative perianal culture. Prior history of MRSA infection or colonization and transfer from outside sources were independently associated with positive MRSA screening cultures. CONCLUSION: The rate of MRSA isolation from screening cultures of newly admitted patients, including in-house transfers, has increased significantly during the past decade in our acute rehabilitation unit. When paired with nares cultures, perianal cultures were of limited value in this patient population.