Isolation, characterization and antibiotic susceptibility pattern of Staphylococcus aureus isolated from in-patients in selected hospitals in Kaduna Metropolis, Kaduna State Nigeria

Abstract

Staphylococcus aureus is an important pathogen associated with various hospital-and communityacquired infections hence constitutes a public health problem. This study was carried out in order to isolate, characterize and determine the antibiotic susceptibility pattern of S. aureus isolated from patients on admission in some selected hospitals in Kaduna metropolis, Kaduna State Nigeria. A total of 300 skin swab samples were collected from in-patients. The swab sticks were inoculated into brain-heart infusion broth, transported to the laboratory and then inoculated on mannitol salt agar. Isolates with the characteristic colonial morphology of S. aureus were then identified microscopically and characterized biochemically. The susceptibility of S. aureus isolates to seven antibiotics was carried out by Kirby-Bauer method. A total of 52 S. aureus strains were isolated from skin swabs. Multiple Antibiotic Resistance (MAR) index analysis showed that the MAR indices of the isolates were between 0.14 and 0.71. Most of the isolates had MAR values greater than 0.2 suggesting that the isolates were from high risk environment where antibiotics are frequently used. The occurrence of S. aureus from this study was found to be 17.33%.

Keywords: Antibiotic, hospital, in-patients, MAR index, Staphylococcus aureus, susceptibility