A molecular and epidemiological study on methicillin-resistant Staphylococcus aureus

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major health hazards and became of greater public health concern since the emergence of MRSA. Among 379 staphylococcal isolates recovered from different clinical sources, 258 (68.1%) were identified as Staphylococcus aureus (S. aureus) with high detection percentage in urine (37.46%). Out of 258 S. aureus isolates, only 27% were phenotypically positive MRSA. All MRSA isolates were resistant to amoxicillin and cefuroxime. Only 50% of the isolates were sensitive to vancomycin. Higher minimum inhibitory concentration (MIC) of oxacillin (256 µg ml-1) was detected for 12.9% of MRSA isolates. Screening 20 selected MRSA isolates for the presence of resistance genes (Type I, Type II, Type III, Type Iva, Type IVb, Type IVc, Type IVd, Type V, MecA and Luk-PV) showed highest prevalence of mecA and Luk-PV genes with 60 and 50%, respectively. The coexistence of more than one gene was detected in many isolates which was correlated to high resistance to antibiotics.