[01] Abdulhadi Sale Kumurya, Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria.

Background: Glycopeptides have been the last in the line of antibiotics used to treat serious MRSA infections. The emergence and spread of multi-resistant methicillin resistant Staphylococcus aureus (MRSA) strains, especially those resistant to fusidic acid and rifampicin in Nigerian hospitals is of concern. Objectives: The main objectives of the study were to determine the resistance rates of fusidic acid and rifampicin among MRSA strains in Northwestern Nigerian hospitals. Methods: In this study PCR was performed for detection of mecA gene from S. aureus isolates. Antibiotic susceptibility testing using disc susceptibility testing and minimum inhibitory concentration (MIC) were performed on 423MRSA isolates from 8 health institutions across Northwestern Nigeria. The isolates were obtained from clinical samples collected for duration of two years from February 2008 to April 2010. The resistance was confirmed by determination of MIC of fusidic acid and rifampicin. Staphylococcus aureus ATCC 25923 was used as a reference control organism. Results: 0f 432 MRSA isolates, 21(4.9%) and 27(6.4%) were found to be resistant to fusidic acid and rifampicin respectively. All the 21 and 27 isolates were confirmed to be resistant with MIC of >25mumg/L and >45mumg/L to fusidic acid and rifampicin respectively. Conclusion: The information gained from the epidemiology of fusidic acid and rifampicin- resistant isolates can help the hospitals infection control teams understand the epidemiology of these organisms in their institutions. Surveillance of these strains should be carried out to prevent further spread of the clone. Increase resistance to fusidic acid and rifampicin will further reduce the already limited treatment options for MRSA infections.

Fusidic Acid, Rifampicin, MRSA, Resistance, Northwestern Nigeria

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