Korean J Clin Microbiol.  2009 Dec;12(4):169-173.

Evaluation of ChromID MRSA for the Detection of Methicillin-resistant Staphylococcus aureus

• Kim MJ
• Kang DH
• Park JI
• Choi TY

Abstract

BACKGROUND
Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen in both nosocomial and community settings, and screening for a carrier is an important infection control practice in many hospitals. We evaluated the sensitivity and specificity of the ChromID MRSA assay (bioM?rieux, Marcy I'Etoile, France).
METHODS
A total of 190 clinical samples were collected from the anterior nares of premature infants in a newborn intensive care unit (N-ICU). Equal volumes (100microliter) of the samples were inoculated on mannitol salt agar with oxacillin 6 mg/L (MSAO) and ChromID MRSA after emulsifying the screening swab in brain-heart Infusion broth with oxacillin 6 mg/L (BE). The specimens in BE were subcultured on ChromID MRSA after an overnight incubation.
RESULTS
Twenty-one of 190 samples (11%) was positive for MRSA by BE. After a 24 h incubation, the sensitivity/specificity of MSAO was 52%/98% and that of ChromID MRSA was 62%/100%, and at 48 h, the sensitivity/specificity of MSAO was 62%/92% and that of ChromID MRSA was 81%/99%.
CONCLUSION
ChromID MRSA is a useful selective medium for the rapid isolation and identification of MRSA.

Keyword

Methicillin-resistant Staphylococcus aureus (MRSA); Detection; Performance; Culture medium

MeSH Terms

Agar
Humans
Infant, Newborn
Infant, Premature
Infection Control
Intensive Care Units
Mannitol
Mass Screening
Methicillin Resistance
Methicillin-Resistant Staphylococcus aureus
Oxacillin
Sensitivity and Specificity
Agar
Mannitol
Oxacillin

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