Autoimmune versus Non-autoimmune Cutaneous Features in Monogenic Patients with Inborn Errors of Immunity.

Cutaneous manifestations are one of the most common presentations among patients with inborn errors of immunity (IEI). These skin manifestations are often among the first presenting features in the majority of patients preceding the IEI diagnosis. We studied 521 available monogenic patients with IEI listed in the Iranian IEI registry up to November 2022. We extracted each patient's demographic information, detailed clinical history of cutaneous manifestations, and immunologic evaluations. The patients were then categorized and compared based on their phenotypical classifications provided by the International Union of Immunological Societies. Most patients were categorized into syndromic combined immunodeficiency (25.1%), non-syndromic combined immunodeficiency (24.4%), predominantly antibody deficiency (20.7%), and diseases of immune dysregulation (20.5%). In total, 227 patients developed skin manifestations at a median (IQR) age of 2.0 (0.5-5.2) years; a total of 66 (40.7%) of these patients initially presented with these manifestations. Patients with cutaneous involvement were generally older at the time of diagnosis [5.0 (1.6-8.0) vs. 3.0 (1.0-7.0) years;