Yonsei Med J.  2013 Sep;54(5):1282-1284. 10.3349/ymj.2013.54.5.1282.

Detection of Methicillin-Resistant Staphylococcus aureus in Healthcare Workers Using Real-Time Polymerase Chain Reaction

• Kim MH
• Lee WI
• Kang SY

• KMID: 1793180
• DOI: http://doi.org/10.3349/ymj.2013.54.5.1282

Abstract

Healthcare-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have recently become an important issue for healthcare facilities due to high rates of infection, mortality, and high treatment costs. We investigated the frequency of MRSA in healthcare workers (HCWs) via nasal carriage and assessed the performance of the LightCycler(R) MRSA Advanced test. We tested nasal swabs from the anterior nares of participating HCWs at an intensive care unit. Nasal swabs were identified as S. aureus, methicillin-sensitive or methicillin-resistant coagulase-negative staphylococci (MSCoNS or MRCoNS), or MRSA by using conventional culture and the LightCycler(R) MRSA Advanced test. Of the 142 HCWs who participated in this study, only 11 participants (7.8%) were MRSA-positive by conventional culture and MRSA ID, and 24 (16.9%) were positive for mecA by real time polymerase chain reaction (PCR). In terms of diagnostic performance, the LightCycler(R) MRSA Advanced test had a sensitivity of 100%, a specificity of 90.1%, a positive predictive value of 45.8%, and a negative predictive value of 100% compared with conventional culture method. The detection limit of the LightCycler(R) MRSA Advanced test was 103 colony/mL. We concluded that real-time PCR was able to rapidly and sensitively detect MRSA in HCWs. However, MRSA must be confirmed by culture due to false positivity.

Keyword

Methicillin-resistant Staphylococcus aureus; mecA gene; real time PCR

MeSH Terms

Bacterial Proteins/genetics
False Positive Reactions
Humans
Methicillin-Resistant Staphylococcus aureus/genetics/*isolation & purification
Nurses
Physicians
Real-Time Polymerase Chain Reaction/methods
Sensitivity and Specificity
Staphylococcal Infections/*diagnosis
Bacterial Proteins

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