CHANGE OF SKIN ROUGHNESS DUE TO LOWERING AIR HUMIDITY IN A CLIMATE CHAMBER

Rough skin (''dry skin'') is characteristic of atopy and thought to be a pre-stage of atopic eczema. Atopic eczema frequently deteriorates i n winter, which may be related to low air humidity during the heating period. We have assessed skin roughness before and after decreasing ai r humidity to 30% in a climatic chamber. Replicas of clinically non-in flamed and not scaling skin from 10 patients with atopic eczema and 10 controls were taken before and after lowering air humidity for 3 h an d mere analyzed for the roughness parameters R(n), R(Z DIN) and R(Z IS O). After exposure to low air humidity there was a significant increas e of R(Z DIN) from 61.5 mu m to 66.9 mu m (p<0.05) and of R(Z ISO) fro m 63.8 mu m to 66.4 mu m (p<0.05) in patients with atopic eczema, wher eas no significant change occurred in controls. Development of skin ro ughness over 3 h under natural indoor environmental conditions did not indicate spontaneous variations. These quantitative data show that a short period of exposure to low air humidity increases skin roughness and may particularly influence the condition of patients with atopic e czema.