Genetic Analysis of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolated from the Population of Southern Punjab, Pakistan

Abstract

The study was aimed to isolate and identify the methicillin-resistant strains and then detect the genetic variants and investigate S. aureus isolates that were resistant to methicillin found in the community of Southern Punjab. Collecting the isolates of S. aureus from the Southern Punjab region of Pakistan. Isolation and identification of these collected isolates were done by subjecting these isolates to laboratory procedures. A polymerase chain reaction was performed for the molecular and genetic analysis. 60 urine and 40 blood samples were taken from outdoor and indoor patients of the Nishtar Medical College & Hospital, Multan. Gram staining and different biochemical assays were done to confirm the presence of S. aureus. After the confirmation of S. aureus, DNA extraction was performed by a modified method of CTAB. A polymerase chain reaction was performed to analyze the size of amplicons found in the Southern Punjab community. In order to check the resistance and susceptibility pattern of S. aureus against beta-lactam antibiotics and fluoroquinolones, the Kirby-Bauer method was used. Out of 100 samples, 98 were cultured on blood agar and mannitol salt agar. 92 tested gram-positive and out of which only 88 gave positive results for the catalase test. When a coagulase test was performed, 85 produced coagulations with plasma in the test tubes. Upon antibiotic susceptibility testing, 50 samples were found as methicillin-resistant S. aureus.67% of methicillin-resistant S. aureus contains mecA3, femA3, aac(6’)/aph(2’’), Tet(K)13, Tet(M)13 genes and methicillin-susceptible S. aureus has 33% less prevalence as compared to methicillin-resistant S. aureus. Southern Punjab region of Pakistan was found to possess the genes mecA3, femA3, aac(6')/aph(2''), Tet(K)13, and Tet(M)13. Southern Punjab region outnumbered in Methicillin-resistant S. aureus(MRSA) isolates in terms of the prevalence of mecA3, femA3, aac(6’)/aph(2’’), Tet(K)13, Tet(M)13 genes. Non-beta lactam antibiotics can be used to treat MRSA infections.