Molecular Diversification and Frequency of mecA Gene in the MRSA Infections of Hospitalized Patients at Islamabad, Pakistan

Abstract

Objective: To determine the molecular diversification and frequency of mecA Gene in MRSA infections of hospitalised patients at Islamabad, Pakistan.

Study design: Cross-sectional study.

Place and Duration: Pakistan Institute of Medical Science, Islamabad, Pakistan, from Sep 2017 to Sep 2018.

Methodology: To explore the occurrence of pathogenic S. aureus in the hospitalised patients of Islamabad, 500 samples were collected. All the isolates were further characterised by gram staining, catalase test and DNAse media analysis validating the presence of S.aureus. The overall frequency of S.aureus was 19.5% in all the isolates. Six highly distinguished colonies were further evaluated through colony PCR by 16S r RNA analysis, and results revealed 99.9% homology of isolates with S.aureus. The degree of resistance was further evaluated for 12 isolates based on the previous MRSA resistance pattern. The extraction and concentration of DNA were done by the CTAB and Nanodrop methods. Then primers were designed for the presence of the mecA gene of S. aureus.

Results: Results showed 51 (52.7%) MSSA and 45 (47.4%) MRSA among all the isolates. Colony PCR by 16S r RNA analysis results revealed 97 (99.9%) homology of isolates with S.aureus. PCR of all the twelve extracted DNAs of isolates showed the frequency of the mecA gene in all the isolates.

Conclusion: The study is the first report the presence of resistance mecA gene in the hospitalised patients of Islamabad. It has depicted a resistant gene's presence and showed the rising trend of resistance in pathogenic S. aureus.