In a recent paper published in the Journal of Clinical Microbiology, MRSA ID a chromogenic media from bioMérieux, was evaluated for its ability to identify methicillin-resistant Staphylococcus aureus.

A well-defined collection of staphylococci in pure culture was used (n = 998). The sensitivity after 24 h was found to be 96.4%, increasing to 98.8% after 48 h. The specificity was 98.2% after 24 h and decreased to 89.7% after 48 h.

The authors concluded that MRSA ID is sensitive and specific for differentiation between Methicillin susceptible Staph aureus (MSSA) and MRSA in vitro. MRSA ID is able to detect a large number of different MRSA strains. The performance of MRSA ID was significantly better after 24 h than after 48 h of incubation. Therefore, with MRSA-ID, optimal results can be obtained within a day. Further clinical studies are required to determine the utility of MRSA ID for the detection of MRSA directly from clinical samples.

Reference:
Bram M. W. Diederen, Marie-Louise van Leest, Inge van Duijn, Piet Willemse, Peter H. J. van Keulen, and Jan A. J. W. Kluytmans
Performance of MRSA ID, a New Chromogenic Medium for Detection of Methicillin-Resistant Staphylococcus aureus
Journal of Clinical Microbiology, February 2006, p. 586-588, Vol. 44, No. 2