Molecular analysis of methicillin resistance and beta-lactamase production by clinical isolates of Staphylococcus aureus in Ekpoma, Edo State Nigeria

Background: Staphylococcus aureus-associated infections continue to be a public health challenge in resource-limited developing countries of sub-Saharan Africa. Understanding the genetic basis of resistance of Staphylococcus aureus remains a paramount panacea to associated illnesses. Objective: To isolate and identify methicillin-resistant and beta-lactamase-producing Staphylococcus aureus from a different clinical specimen collected from hospital attendees in Ekpoma, Edo State Nigeria. Materials and methods: A total of 200 Staphylococcal isolates were recovered from different clinical specimens analyzed. Standard Microbiological methods used in the isolation and identification of Staphylococcus aureus included the use of ProlexTM Staph Latex Kit, cultivation in MRSA Chromagar, and confirmation using species-specific oligonucleotide primers to amplify DNA regions of interest and result read by electrophoresis. Results. Out of 200 isolates of Staphylococcus aureus isolates, 80(40%) strains were positive for the mecA gene, while 120(60%) were beta-lactamase positive. Age groups 26 – 30 had 23.0% of S. aureus with 25.0% positive for MecA gene and 30.0% positive for β-lactamase production. S. aureus from wound swabs had a 52% high potential for 52% for β-lactamase production and 42.5% for the mecA gene. Female/male urine had 40.9%/20.0% prevalence of S. aureus. Methicillin resistance and beta-lactamase production were high (25% and 30% respectively) among isolates from urine samples. Conclusion. Methicillin-resistant (mecA) genes and beta-lactamase enzymes remain important determinants of resistance of Staphylococcus aureus to conventional antibiotics in resource-limited settings. Strict use of prescription drugs to avoid abuse, improved personal hygiene, good laboratory practice, screening of all in-patients upon admission into the hospitals, screening of visitors during visits to in-patients, hand washing, and the use of disposable aprons and gloves by staff to reduces skin-to-skin contact and therefore further reduce the risk of transmission are strongly recommended