Abstract

We determined the in vitro effect of vancomycin on multidrug resistant Staphylococcus aureus isolates and presumptive roles of plasmid DNA using standard microbiological procedures. A total of 32 paper naira notes from seven different hospital sections (mostly from the patients) were analyzed. Thirteen notes (40.6%) gave isolates of S. aureus and subsequent resistant range of between 62.5 and 100% to frequently prescribed antibiotics. The same set of isolates showed three (23.1%) to be susceptible and ten (76.9%) to be resistant to vancomycin. Five of the latter ten isolates produced beta lactamase and became susceptible to some of the multidisc antibiotics and vancomycin, after the plasmid curing. This presumptively reflects important role of plasmid DNA in conferring resistance to microorganisms as a means of their adaptation especially in the vancomycin resistant S. aureus (VRSA). The increasing resistance to vancomycin could cause major problems to public health as it was often regarded as the last line of defense against nosocomial and community based S. aureus infection.

Key words: Vancomycin, multidrug, plasmid, beta lactamase, antibiotic resistance.