mecA-gene detection and MDR profile of S. aureus isolates from patients attending the Referral Hospitals of Amhara Reginal state, Ethiopia

Abstract Background: Staphylococcus aureus causes different types of human infections and has the ability to develop resistance to many antibiotics. There is a scarcity of data on the mecA gene and MDR profiles of this organism in developing countries, like Ethiopia. The aim of the present study is, therefore, to investigate MDR profiles and the mecA-gene profile of S. aureus from Referral Hospitals of Amhara Reginal State. Methods: Of the total of 110 isolates collected from Amhara Region Referral Hospitals, 70 MDR isolates were further processed for isolation of S. aureus mecA gene. Genomic DNA was isolated using SIGMA ALDRICH genomic DNA isolation Kit for Gram positive bacteria. Amplification of S. aureus mecA gene was done using amplicon size of 533 bp. Agarose gel electrophoresis was prepared with 1.5% agarose by TAE solvent and 0.5μg/mL of ethidium bromide. Electrophoresis was carried out for 1 hour and a half (7 Volts/ cm²) in 1X tris acetate EDTA (TAE) buffer. Data were analysed by using descriptive statistics.Results: The Majority of the isolates were recovered from patients aged less than 5 years, 51 (36.7%) and least from age greater than 60 years, 6 (4.3%). Most of the isolates were from blood, 61 (43.9%), followed by wound, 45 (32.4%). High resistance rate was observed in penicillin 81 (73.6%), followed by cotrimoxazole 78 (70.9%), ceftriaxone 76 (69%), erythromycin 66 (60%) and tetracycline 65 (59.1%). Phenotypically, considering cefoxitin as a surrogate marker, 38 (34.5%) of the isolates were methicillin-resistant. The overall MDR isolates were 92 (83.6%). The PCR amplification result of mecA gene was 14 (20%).Conclusions and recommendations: There is a high rate of MDR and MRSA isolates of S. aureus. PCR amplification result indicates 20% of MRSA isolates are mecA gene producers. Largescale study for detection of MDR strains of S. aureus including MRSA using molecular techniques should be encouraged in the Amhara region.