Comparative Study Of Two Lactamase Detection Methods In Staphylococcus aureus Isolated From Students Of Michael Okpara University Of Agriculture, Umudike

ABSTRACT

This study was carried out following standard procedures to compare the practicability of the 4 acidometric and iodometric test methods for 1 lactamase production in Staphylococcus aureus isolated from students of Michael Okpara University of Agriculture, Umudike. The total of 1 00 swab samples collected from the ear and nose of the students were cultured on Mannitol Salt Agar plates. Further identification by coagulase, catalase and DNase tests were carried out on the isolates. The isolates were subjected to antimicrobial susceptibility testing by Kirby-Bauer disk diffusion method. Resistance to Augmentin was observed in 58 (93.5%) isolates while 49 (79.0%) isolates were susceptible to Ofloxacin. Sensitivity, specificity and efficacy of the test methods for the determination of f3 lactamase production were calculated taking penicillin resistance and sensitivity as the standard. Acidometric method was found to be the more sensitive (96.1%) and efficient (95.2%) test and had a high positive predictive value. The iodometric test method was found to be relatively less sensitive (76.5%) and efficient (77.4%). The acidometric method was found to be the better method for the detection of 1 lactamase production. The study also notes the alarming prevalence rate of 3 lactamase producing S. aureus among healthy individuals which indicates the need for treatment by 1 lactarnase susceptible antibiotics.