title: Clonal T-cell populations in pityriasis lichenoides et varioliformis acuta (Mucha-Habermann disease).
abstract: Patients with the skin disorder pityriasis lichenoides et varioliformis acuta (PLEVA) develop recurrent, self-healing papulonecrotic lesions that contain infiltrates of cytologically and antigenically normal T lymphocytes. DNA extracted from the lesions of 3 patients with PLEVA was analyzed for rearrangement of beta-T-cell receptor genes for the purpose of assessing the clonality of T lymphocytes within the tissues of this disease. Lesions from all 3 cases showed clonal gene rearrangements. In each of 2 cases from which two separate lesions were biopsied, identical rearrangements were found in specimens from both sites. DNA from a variety of inflammatory lesions obtained from patients with other types of skin diseases failed to show detectable rearrangements of beta-T-cell receptor genes. These results suggest that PLEVA represents a T-cell lymphoproliferative process, rather than an inflammatory disorder, as had been previously thought.
mesh_terms: D004262:DNA Restriction Enzymes; D006801:Humans; D008232:Lymphoproliferative Disorders / Q000473:pathology; D010267:Parapsoriasis / Q000276:immunology / Q000473:pathology*; D010915:Pityriasis / Q000276:immunology / Q000473:pathology*; D011948:Receptors, Antigen, T-Cell / Q000032:analysis / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology*
chemical_list: D011948:Receptors, Antigen, T-Cell; D004262:DNA Restriction Enzymes