Persistent methicillin-resistant Staphylococcus aureus (MRSA) nares test positivity during initial days of systemic antistaphylococcal antimicrobial therapy.

Abstract

The typical duration of positive nucleic acid tests for methicillin-resistant Staphylococcus aureus (MRSA) in the nares of patients receiving systemic anti-MRSA antimicrobials is unknown. In this study, hospitalized adult patients with an initial positive MRSA nares nucleic acid test prescribed systemic anti-MRSA antimicrobials had follow-up testing done 48 to 96 hours later. A positive follow-up test was detected in 100/113 (88.5%), indicating that MRSA nares DNA tests still have utility for screening after patients have initiated anti-MRSA therapy.