Bacteriology and antibiogram of pathogens from wound infections at Dessie Laboratory, North East Ethiopia

Abstract

Wound infections result in sepsis, limb loss, long hospital stays, higher costs, and are responsible for significant human mortality and morbidity worldwide. The aim of this study was to investigate the profile of pathogens cultured from wound infection and determine the antimicrobial susceptibility patterns.  A retrospective analysis of bacterial pathogens and their antimicrobial susceptibility was done on wound swab samples that have been cultured at Dessie Regional Laboratory from 2003 to 2010. Antimicrobial susceptibility tests were done using disc diffusion technique as per the standard of Kirby-Bauer method. The mean age of male and female patients was 31.2 and 29.8 years, respectively with male to female ratio of 1:1.6. Out of 599 wound swab samples analyzed, 422 (70.5%) were culture positive.  A total of 500 bacteria from 422 positive cases were identified. Seventy eight (18.5%) of the culture had double infections. Staphylococcus aureus was the most frequently isolated pathogen which accounted for 208 (41.6%) of isolates followed by Pseudomonas spp. 92 (18.4%), E. coli 82 (16.4%), Proteus spp. 55 (11.0%), Enterobacter spp. 21 (4.2%), and Citrobacter spp. 21 (4.2%), Klebsiella spp. 12 (2.4%) and Coagulate negative staphylococcus 9 (1.8%). Amoxicillin had the highest resistance rate 78.9%, followed by tetracycline 76.1% and erythromycin (63.9%). The sensitivity rates of norfloxacin, ciprofloxacin and gentamicin were 95.1%, 91.8% and 85%, respectively.  The overall multiple antimicrobial resistances rate was 65.2% and only 13% of the isolates were sensitive to all antimicrobial agents tested. The most frequently isolated bacteria were sensitive to ciprofloxacin, gentamicin, cloxacillin and norfloxacin. These antimicrobials are considered as appropriate antimicrobials for empirical treatment of wound infections. Periodic surveillance of aetiology and drug susceptibility both in the community and hospital settings is recommended.