[The cytoarchitectonics of the epidermis in sarcoidosis of the skin].

Histologic and electron microscopic study of the epidermis in, respectively, 30 and 4 patients with skin sarcoidosis has revealed that atrophy of the epidermis is the most incident condition, whose severity depends on microcirculation disorders that are explained by the location of the epithelioid-cell granulomas relative to skin microcirculatory bed. Moderate atrophy involves the following ultrastructural changes in the keratinocytes: increased count of ribosomes and mitochondria, tonofibril condensation, perinuclear vacuolization, separation of individual cellular contact sites. If atrophy is well manifest, basal keratinocytes grow in size and the nuclei in them are positioned apically. These data suggest that drugs improving the microcirculation be prescribed to such patients in order to obliterate possible cosmetic defects.