Real-time PCR assay for detection of <em>Staphylococcus aureus</em>, Panton-Valentine Leucocidin and Methicillin Resistance directly from clinical samples

Abstract

Rapid detection of Methicillin Resistant <i>Staphylococcus aureus</i> (MRSA) is an important concern for both treatment and implementation of infection control policies. The present study provides an 'in house' real-time PCR assay to detect directly <i>nuc</i>, <i>pvl</i>, and <i>mecA</i> genes. The assay is able to perform identification of MRSA, Methicillin-Sensitive <i>S. aureus</i>, Methicillin-Resistant Coagulase Negative Staphylococci and the Panton-Valentine leukocidin virulence gene from rectal and pharyngeal swab samples in a screening context. We found an analytical sensitivity of this current Triplex PCR assay of 514 CFU/mL. Analytical specificity was tested with different Gram-positive and Gram-negative species and yielded no false-positive PCR signal. The sensitivity and specificity of the Triplex Real Time PCR were both 100% for these targets when compared with the culture and conventional methods. This assay is readily adaptable for routine use in a microbiology laboratory, as it will enable the implementation of timely and properly guided therapy and infection control strategies.