Antimicrobial Resistance Among Common Bacterial Pathogens in South Western Nigeria

The phenomenal increase in antibiotic resistant bacterial pathogens calls for regular review of antimicrobial sensitivity pattern among bacteria of clinical significance in an environment. This study was conducted to determine the common clinically significant bacterial pathogens in this environment and their antimicrobial susceptibility pattern. Bacterial pathogens isolated from various clinical specimens brought to the diagnostic laboratory of the University College Hospital between May and October 2005 were subjected to antimicrobial sensitivity testing using the disc diffusion and minimum inhibitory concentration tests. The most prevalent bacterial pathogen was found to be Staphylococcus aureus (47.5%), followed by Pseudomonas aeruginosa (24.6%), Klebsiella species (23%), Proteus species (3.3%) and Escherichia coli (1.6%). P. aeruginosa (24.6%) rated highest in frequency among the Gram-negative organisms while S. aureus was the main Gram-positive pathogen isolated. Generally, resistance rates to most of the antibiotics tested were high among both Gram-positive and Gram-negative isolates. However, both groups showed good susceptibilities to gentamycin and ciprofloxacin. Resistance to the old generation antibiotics such as streptomycin and chloramphenicol, nevertheless, remained persistently high. This study has further revealed that continued surveillance of changes in resistance patterns of bacterial pathogens to antibiotics is of utmost importance if effective management of infectious diseases is to be ensured.