Antinuclear antibody positivity rate and clinical characteristics in prurigo chronica multiformis: a retrospective study of 26 patients
TL;DR
It is suggested that prurigo chronica multiformis may include an immunologic subtype in which autoimmunity and allergic inflammation intersect, and ANA-positive patients showed a high rate of allergen sensitization and a lower peripheral blood eosinophil percentage.
Abstract
Prurigo chronica multiformis is a refractory chronic pruritic dermatosis that predominantly affects older adults, but the frequency and significance of antinuclear antibody (ANA) positivity remain unclear. This retrospective single-center study included 26 patients with prurigo chronica multiformis treated between March 2016 and April 2025. Patients were divided into two groups according to ANA status, and baseline characteristics, allergic background, laboratory investigations, extent of skin involvement, and responsiveness to topical corticosteroids were compared. Five of 26 patients (19.2%) were positive for ANA. Among evaluable patients, all patients in the positive group showed sensitization to at least one allergen, which was more frequent than in the negative group (100% vs. 37.5%, p = 0.035). The median peripheral blood eosinophil percentage was significantly lower in the positive group (4.0% vs. 8.0%, p = 0.031). No significant differences were observed in the eosinophil count, total IgE levels, extent of skin involvement, or responsiveness to topical corticosteroids. Approximately one-fifth of patients with prurigo chronica multiformis were positive for ANA. ANA-positive patients showed a high rate of allergen sensitization and a lower peripheral blood eosinophil percentage. These findings suggest that prurigo chronica multiformis may include an immunologic subtype in which autoimmunity and allergic inflammation intersect.