Phenotypic and genotypic detection of extended spectrum B-lactamases (ESBLS) and methicillin-resistant Staphylococcus aureus isolates in Kirkuk/Iraq

Methicillin-resistant Staphylococcus aureus is an intrusive human pathogen causing community- and hospital-acquired infections worldwide. S. aureus was discovered to be one of the leading sources of hospital infections and drug resistance in Iraq, particularly methicillin resistance. The aim of the study is to know the extent of the prevalence and resistance to antibiotics in S. aureus bacteria isolated from samples collected during the period of November 2021 to March 2022 from the Kirkuk Hospital. A total of 150 clinical samples (burn, urine, diabetic foot ulcer, and sputum) were used according to gender and age range (30–79 years). The results of antibiotic susceptibility testing for S. aureus infections showed resistance to Penicillin, Ceftazidime, Erythromycin, Clindamycin, Azithromycin, and Doxycycline at 100%, 68%, 64%, 74%, and 40%, respectively. Twenty S. aureus out of 50 isolates were identified as MRSA isolates, and 19 (95%) isolates were identified as having multi-drug resistance (MDR). All MRSA isolates were screened for 16srRNA, mecA, Blazβ, blaDHA-1, and blaOXA-1 using PCR. Only 15 (75%) isolates showed positive results for the mecA gene, while 20/20 (100%) showed Blaz-β genes. Regarding the β-Lactamase detection genes among MRSA isolates, only 12/20 (60%) of MRSA isolates carried the blaDHA-1AmpC genes, while 0/20 (0%) of MRSA isolates showed the blaOXA-1 genes. Improper use of antibiotics among patients in Kirkuk may play an important role in the spread and emergence of antibiotic resistance.