A chromogenic culture medium identifies the 'superbug' methicillin resistant Staphylococcus aureus, giving results in 24 hours with 98% sensitivity and 100% specificity
Over recent years, an increasing number of hospitals have been infected by methicillin resistant Staphylococcus aureus (MRSA) - the so-called superbug.
Unfortunately, traditional culture media continue to produce unsatisfactory results in the detection of MRSA being slow and lacking in sensitivity and specificity. Chromagar MRSA is proving to be a major breakthrough in detecting hospital patients carrying MRSA, says Bioconnections.
Results are obtained within 24 hours, which is a saving of 24 - 48 hours. Evaluations show a sensitivity and specificity close to 100% and there is a tremendous saving in technician time and additional reagents.
Evaluations.
1486 swabs from 608 patients in an intensive care unit were tested for MRSA on admission and thereafter on a weekly basis.
The results obtained by culturing on Chromagar MRSA were compared with cultures on blood agar. Plates were read at 24 and 48 hours and suspect colonies were identified.
Results showed Chromagar MRSA to be 98%sensitive and 100% specific after 24 hours.
Experienced technicians were able to presumptively identify MRSA (mauve/pink colonies) with no further tests.
Confirmatory tests such as catalase, Gram stain and latex agglutination could all be performed directly from the medium.
The product is now in routine use in several UK hospitals.
