Pachyonychia congenita. Electron microscopic and epidermal glycoprotein assessment before and during isotretinoin treatment

Abstract

Patients (2), a father and son, with pachyonychia congenita were treated with orally administered isotretinoin because the extreme deformity and discomfort associated with their massive keratoderma interfered with their work and school. While clinical benefits could not be sustained, EM findings compatible with abnormal keratinization suppression were observed. Skin biopsy samples were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The gels were then subjected to a lectin overlay technique with concanavalin A labeled with iodine 125. Specific glycoproteins distribution was found to be different for lesional and normal epidermis. The procedure was repeated after oral treatment with isotretinoin. The labeled glycoprotein pattern of the lesional epidermis was clearly distinguishable from both the pretreatment lesional and the normal epidermis; it was mostly intermediate between the 2. The normal epidermis was virtually unaffected by the retinoid treatment.