In Vitro Antimicrobial Susceptibility Testing of Bacterial Isolates Causing Wound Infection in A Tertiary Care Hospital, Port Harcourt, Nigeria

Abstract

A successful treatment of wound infection is determined by the proper identification and evaluation of the varied types of microorganisms that colonize the wound surface. Such evaluation will include an antimicrobial susceptibility profiling of the invading pathogen(s) in order to implement an effective and pathogen specific treatment. The antimicrobial susceptibility profile of the bacterial species isolated from wound infections was tested to provide basis for their prudent use as antimicrobials. The standard method of antibiotic sensitivity testing with single antibiotic disc was employed in the analysis. The bacterial isolates tested were Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. The organisms were isolated from samples collected from patients at different wards at the University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria. The number and percentage occurrence of each individual bacterium encountered varied among the isolates. Pseudomonas aeruginosa has the highest frequency of occurrence of 48.6% accounting for 36 of the 74 bacterial isolates. This was followed by Staphylococcus aureus and Escherichia coli accounting for 17 (23.0%) and 11 (14.9%) respectively. Klebsiella pneumoniae was the least prevalent bacteria species accounting for 10 (13.5%) of the total bacterial count. The study shows imipenem as the most potent antimicrobial agent against the isolates tested. The isolates were moderately sensitive to gentamicin, ciprofloxacin and levofloxacin, but highly resistance to ceftazidime, erythromycin, sulphamethoxazole/trimethoprim, cefepime, amoxicillin/clavulanic acid and aztreonam. The study further reiterates the need for prudent use and control of antimicrobials.