Active surveillance of methicillin-resistant Staphylococcus aureus with the BD GeneOhm MRSA™ assay in a respiratory ward in Nagasaki, Japan.

The utility of active surveillance cultures (ASCs) in respiratory wards, that do not have an associated intensive care unit (ICU), and the usefulness of the BD GeneOhm MRSA™ system for rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) have not been previously evaluated in Japan. ASCs using conventional culture methods and the BD GeneOhm MRSA™ assay were conducted in adult inpatients between May 11, 2009 and November 10, 2009 in a respiratory ward, without an associated ICU, in Nagasaki University Hospital. The infection and colonization rates of MRSA acquired in this respiratory ward were both investigated. A total of 159 patients were investigated. Of these, 12 (7.5%) were found positive for MRSA by the BD GeneOhm MRSA™ assay and 9 (5.7%) were found positive by a conventional culture test upon admission. All cases were MRSA-colonized cases and cross-transmission was not found to occur during hospitalization. The BD GeneOhm MRSA™ assay had a sensitivity of 100% and a specificity of 98%. ASCs in our respiratory ward revealed that MRSA was brought in from other sites in some cases, and that current infection control measures in Nagasaki University Hospital are effective. The BD GeneOhm MRSA™ assay was proven to be a useful and rapid detection tool for MRSA.