Molecular Detection of Beta-Lactam Resistance Genes in Staphylococcus Aureus Isolated From Women in Nasarawa State, Nigeria

Resistance to antimicrobials by pathogenic microorganisms has raised serious global clinical concerns in recent times. The present study aimed at detection of β-lactam resistance genes in S. aureus isolates from women with symptomatic and asymptomatic cases of urinary tract infections in Nasarawa state, Nigeria. A total of 200 non-repetitive midstream urinal samples were analysed and 50 (29%) bacterial isolates were identified as S. aureus. The susceptibility profile of the bacterial isolates to tested antibiotics was Nitrofurantoin (74.1%), Gentamicin (72.4%), Ciprofloxacin (65.5%), Ofloxacin (56.9), Augmentin (36.2%), Cotrimozazole (29.3%), Ampicillin (27.6%), Erythromycin (25.8%), Ceftazidine (20.7%) and Cefurozime (10.3%). Thirteen bacterial isolates were found to be resistant to all β-lactam antibiotics tested, out of which 7 were confirmed β-lactamase producers using the acidometric and iodometric methods. The detection of β-lactamase genes (blaZ, blaI and blaR1) was carried out and only five of the isolates were found to be expressing the blaI genes. This research finding suggests that β-lactam resistance by S. aureus may not be dependent only on the blaZ, blaI and blaR1 genes.