Evaluation of single and double-locus real-time PCR assays for methicillin-resistant Staphylococcus aureus (MRSA) surveillance

Table 1 Validation of pure cultures by single and double-locus detection assays

	Real Time PCR results
Pure culture strains Total n = 150	Cuny's[7] single-locus detection^a		Huletsky's[8] single-locus detection^b		Reischl's[5] double-locus detection^c
	SCC:orfX+ (MRSA)	SCC:orfX- (other)	SCC:orfX+ (MRSA)	SCC:orfX- (other)	Sa442+ mec+ (MRSA)	Sa442+ mec- (MSSA)	Sa442- mec+ (Oxa. resistant)	Sa442- mec- (other)
MRSA (n = 50)	49	1	49	1	50	---	---	---
MSSA (n = 50)	14	36	2	48	---	48	---	2
MR-CoNS (n = 25)	---	25	---	25	---	---	25	---
MS-CoNS (n = 25)	---	25	---	25	---	---	---	25

^a sensitivity = 98%, specificity = 86%, Positive predictive value = 77.8%, Negative predicted value = 98.9%
^b sensitivity = 98%, specificity = 98%, Positive predictive value = 96.1%, Negative predicted value = 99%
^c sensitivity = 100%, specificity = 100%, Positive predictive value = 100%, Negative predicted value = 100%

ISSN: 1756-0500