Changes in cutaneous flora after wet occlusion

Abstract

Aerobic flora from wet-occluded forearms of six volunteers was sampled the day before treatment, on the 3rd day when dressings were removed, and daily, when possible, for 8 days thereafter. Erythema was not present. All bacterial colonies appearing on appropriate dilution plates were identified with the aid of a replica-plating technique. Flora of each individual increased to over 104 colony-forming units/cm2 as a result of wet-occlusion, but counts rapidly fell by about 102 units once dressings were removed. Although similar types of bacteria were found on all subjects, the composition of each individual's flora during the recovery response appeared to be unique. Enterobacteriaceae were found on half the subjects with Enterobacter aerogenes being the most successful colonizer. Besides the expected presence of Baird-Parker Staphylococcus subgroup II, high numbers of subgroup IV and some colonies of subgroup III were also observed. Almost all cutaneous diphtheroids were lipophilic and lipolytic.