Local steroid therapy and bacterial skin flora in atopic dermatitis.

A double-blind, randomized trial was conducted to determine the influence of topical steroid therapy on atopic skin flora. The bacteriological and clinical effects of desonide (Locapred), compared with those of its excipient, were studied in 40 children. Clinical scoring and bacteriological sampling were performed before the start of the trial and after 7 days of once-daily topical treatment. Before treatment, no differences in clinical score or Staphylococcus aureus colonization were noted between the two groups. After treatment, the clinical score improved (P < 0.001) in the desonide group, and S. aureus density decreased dramatically (P < 0.001). In the excipient group, no significant differences in clinical score or S. aureus density were noted. A comparison of the two groups demonstrated statistically significant differences with regard to clinical score (P < 0.001) and S. aureus density (P < 0.05). These results show the efficacy of topical corticosteroid treatment alone on S. aureus colonization in atopic skin, and confirm the critical role of inflammation in bacterial colonization.