Original Article. Evaluation of Rapid Detection of Nasopharyngeal Colonization with MRSA by Real-Time PCR

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Objective To investigate the clinical application of Real-Time PCR for rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) directly from nasopharyngeal swab specimens.

Methods We collected the nasal and throat swab specimens from patients or medical staffs in 3 intensive care units, blood laminar flow ward and respiratory ward in Beijing Hospital, Ministry of Health from December 2010 to April 2011. Each sample was tested by RT-PCR and conventional culture-based method for the presence of MRSA.

Results The total number of the specimens was 206. Compared with the conventional culture-based method, we demonstrated the diagnostic values for Real-Time PCR were 96.4% sensitivity, 96.6% specificity, 81.8% positive predictive rate, and 99.4% negative predictive rate. And the limit of detection was 102CFU/ml.

Conclusions This Real-Time PCR is a simple, rapid, sensitive and specific method. With the high negative predictive value, it can be used for the exclusion of MRSA colonization or infection. However, the application of its low positive predictive value should be further evaluated.

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