Cumulative yield from patient surveillance cultures for methicillin-resistant Staphylococcus aureus during a hospital outbreak.

The cumulative yield from cultures of separate sites was determined during the investigation of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak. Surveillance cultures were submitted from clinical sites, nose, groin, and axilla of 421 patients on two different occasions. MRSA was recovered most often from various clinical sites, including lower respiratory tract, surgical wounds, urinary tract, and decubitus ulcers (total, 13 patients). Four additional patients were identified as positive from the first nasal swab, one patient from the second nasal swab, and two others from swabs of the groin. The submission of axillary swabs or a second groin swab did not identify additional MRSA-colonized patients and resulted in additional costs of $4,525.