Utility of a single nasal polymerase chain reaction assay in predicting absence of skin and environmental contamination in hospitalized patients with past methicillin-resistant Staphylococcus aureus.

We evaluated hospitalized patients with a history of methicillin-resistant Staphylococcus aureus (MRSA) for persistent colonization and need for contact precautions. Up to 3 daily cultures of nares, skin, and any present wounds were compared with a single nasal polymerase chain reaction (PCR) assay. Most patients (76.2%) were no longer colonized with MRSA. A single PCR assay was sufficient to exclude persistent colonization and environmental contamination and remove the contact precautions.

"Bringing down the flag": removing the contact precautions label for non-hospitalized patients with prior methicillin-resistant Staphylococcus aureus infection or colonization.

A policy consensus has not been reached regarding discontinuing contact precautions in patients with a history of methicillin-resistant Staphylococcus aureus (MRSA). We found that as many as 72% of outpatients flagged for past MRSA were no longer carriers, and a single nasal PCR test provided a reasonable negative predictive value for removing contact precautions.