Susceptibility of clinical isolates of uropathogenic bacteria from Southwest Nigeria to antibiotics and extracts of Brachystegia eurycoma Harms (Leguminosae)

Abstract

Resistance of uropathogens to antibiotics has been on increase and responsible for increased mortality and morbidity among patients. Clinical isolates (22) of uropathogenic bacteria comprising Escherichia coli, Klebsiella Pneumoniae, Proteus mirabilis and Staphylococcus aureus were tested for susceptibility to standard antibiotics and extracts of Brachystegia eurycoma . Methanolic extracts of leaves, stem and root barks of the plant were screened at 20mg/ml against the organisms using agar well diffusion method. Susceptibility of the isolates to plant extracts and standard antibiotics (amoxicillin, gentamicin, ofloxacin, chloramphenicol, tetracycline, augmentin, nalidixic acid, nitrofurantoin, erythromycin and cotrimoxazole) was done using agar disc diffusion methods respectively. Minimum Inhibitory Concentrations (MICs) of the extracts were determined by agar-dilution method on some of the uropathogens. Ofloxacin was the most active against E. coli, K. pneumoniae and P. mirabilis while gentamicin and chloramphenicol were the most active on S. aureus . The plant’s extracts showed good activity on most of the uropathogens, even on the multidrug resistant (MDR) isolates of S. aureus and P. mirabilis. The MIC of B. eurycoma extracts on E. coli, K. pneumonia and S, aureus varied from 0.06 to 1.0mg/ml. This study showed that MDR uropathogens were still prevalent in Southwest Nigeria and that extracts of B. eurycoma contains bioactive compounds having good antibacterial activity, especially on the MDR clinical isolates. The overall results indicated varied patterns of sensitivity and resistance to antibiotics and extracts, warranting judicious and rational use of antibiotics in the routine treatment of UTI to prevent recurrence and development of resistant strains. Keywords : Uropathogens; Resistance; Antibiotics; Brachystegia eurycoma extracts; MIC.