[Considerations of the pathogenesis of parakeratosis variegata based on morphologic and molecular genetic findings].
We report on a 63-year-old woman who had been suffering from generalized parakeratosis variegata since she was 7 years old. Increased tightness of the skin was the only clinical symptom. On the whole integument except for the face, we found a fine network of hyper- and depigmentation and telangiectasias. The skin surface was dry and atrophic with fine lamellar scaling. Histological, immunohistological and ultrastructural findings indicated early infiltration by a cutaneous T-cell lymphoma. However, PCR analysis of the T-cell receptor gamma-chain genes revealed multiple amplification products favouring a polyclonal T-cell proliferation. In light of the clinical history over a period of 56 years, we consider parakeratosis variegata to be a benign, chronic inflammatory condition, as is confirmed by the results of PCR analysis in this patient.