Antibiotic Susceptibility Pattern of Staphylococcus aureus Strains from Patients in Ethiopia

Staphylococcus aureus (S. aureus) is one of the most serious gram-positive bacteria causing several infections. Because of its intrinsic ability to develop resistance to antibiotics, nowadays only few drugs can be confidently mentioned for the treatment of S. aureus infections. The study aimed to investigate the antibiotics susceptibility pattern of S. aureus among patients.
A cross-sectional study was conducted on antibiotic susceptibility of S. aureus among patients. A total of 323 wound and nasal swab specimens were collected and inoculated on mannitol salt agar (Oxoid) and incubated at 37oC for 18 to 24 hours. Gram-staining and specific biochemical tests were used to identify the study organism. Sensitivity of the isolates to ten commonly used antibiotics was determined by Kirby-Bauer antibiotic sensitivity testing method. The isolates were found to be highly resistant to penicillin G and cephalothin (98.8%; each). Chloramphenicol, amoxicillin/clavulanic acid and oxacillin were also resisted by 53.1%, 50.6% and 38.3% of the isolates, respectively. Least resistance was obtained for ciprofloxacin, vancomycin and gentamycin. There was higher S. aureus prevalence for inpatient isolates than outpatients’. The isolates showed high resistance and multidrug resistance pattern to several combinations of the tested antibiotics.