[01] Kumurya A. S., Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria.

Background: The differentiation of Methicillin resistant Staphylococcus aureus (MRSA) strains from other strains of S. aureus has important implications for the treatment and management of patients with S. aureus infections. Detection of the mecA gene by PCR has been described as a rapid method for the identification of MRSA. Objectives: A molecular assay for the simultaneous detection of a Staphylococcus aureus-specific gene and the mecA gene, responsible for the resistance to methicillin in staphylococci, was evaluated. Methods: In a clinical study, 100 isolates of Staphylococcus aureus were investigated. Polymerase chain reaction (PCR) was used (with a Techne TC-5000 instrument-Bibby Scientific Ltd.) to amplify both the S. aureus specific sequence gene and mecA gene of 100 isolates with the amplicon size of 107 and 532bp. To accelerate the procedure of identification in clinical microbiology laboratories, simple and rapid method for DNA extraction directly from a single colony was employed. The assay included a rapid DNA extraction protocol conducted in 15 minutes and PCR conducted. The performance and robustness of the assay was evaluated with a control strain of methicillin susceptible Staphylococcus aureus-ATCC 25923 (MSSA). The specificity of the new molecular assay was tested with a bacterial strain of methicillin susceptible Staphylococcus aureus-ATCC 25923 (MSSA). Results: All clinical the isolates gave positive results for the S. aureus-specific genomic target, and only five isolates (5.0%) were positive for the mecA gene. Conclusion: The new rapid DNA extraction protocol was found to be quick, robust, and labor saving and it proved to be suitable for a routine molecular diagnostic laboratory. On the basis of this finding; establishment of molecular diagnostic laboratory in secondary and tertiary health units is urgently required.

Staphylococcus Aureus, MRSA, MecA Gene, DNA Extraction, PCR

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