Acid mucopolysaccharides of the dermis in incipient psoriasis.

Acid mucopolysaccharides have been studied in the dermis of 40 cases of incipient psoriasis. In the upper dermis a marked reduction of the material stained with colloidal iron and with Alcian blue solutions containing 0.1 and 0.2 M MgCl2 was observed; enzymatic controls with hyaluronidase support the idea that this material consists mainly of hyaluronic acid. The intensity and the extension of this dermal alteration far beyond the limits of the above-mentioned epidermal alteration give credence to the hypothesis that in the pathogenesis of psoriasis, dermal alterations are of a primitive character.