Bacteriology of wound infection: evaluation by surface swab and quantitative full thickness wound biopsy culture

A total of 171 cases of wounds of various aetiology were examined and screened bacteriologically for evidence of infection by surface swab culture and quantitative full thickness wound biopsy culture techniques. Staphylococcus pyogenes was the most frequently isolated (39.9%) single organism. Other organisms being Escherichia coli (26.1%), Pseudomonas aeruginosa (15.4%), klebsiella species (5.8%), Streptococcus pyogenes (4.9%), proteus species (4.8%) and coliform organism (3.1%). Collectively the Gram-negative organisms were the majority among the isolated organisms. As indicator of wound infection, surface swab culture was found to be reliable in 72% cases when correlated with wound biopsy culture. The latter technique was found to be more consistently valuable (in 95% cases) both for regular assessment of the wounds as well as to judge the response to treatment.