Polymerase chain reaction screening for methicillin-resistant Staphylococcus aureus and contact isolation

Methicillin-resistant Staphylococcus aureus (MRSA) infections are thought to now be endemic in some populations. The early identification of individuals admitted to the hospital who are harboring this organism is important for the timely implementation of appropriate control strategies. Our objective was to measure the prevalence of MRSA carriage in high-risk patients entering our hospital and to determine which of these patients screened for MRSA should be placed in contact precautions on admission.

Between January 1, 2007, and December 31, 2007, we used polymerase chain reaction analysis, with a turnaround time of 4 hours or less, to screen for MRSA in a select group of patients entering our hospital.

We screened 1,568 patients and found 144 (9.2%) positive. Of the 1,568 patients, 170 (10.8%) were known to previously have been MRSA positive. Of these, 90 (52.9%) had negative screens.

We used a rapid screening test to identify patients harboring MRSA. Our findings support that MRSA is harbored sporadically and patients do not have to be placed in contact isolation based on a history of previously being MRSA positive.