Cutaneous Manifestations of Inborn Errors of Immunity: Clinical Clues to Immune Disorders.

Background/Objectives: Cutaneous manifestations of inborn errors of immunity (IEI) are among the most common and often early signs of these disorders, estimated to affect about 40% of patients with IEI, and in some cases, they provide the first diagnostic clue. Skin findings in IEI are heterogeneous and include recurrent skin infections, severe atopic dermatitis, autoimmune manifestations, as well as atypical granulomatous dermatoses, neoplastic lesions, pigmentation disorders, and changes involving hair and nails. Early recognition of these manifestations and linking them to the appropriate immunologic defect is crucial for establishing the diagnosis and initiating targeted therapy. Methods: This paper reviews the dermatologic phenotypes associated with IEI, with particular emphasis on a tabular classification of skin lesions corresponding to specific immunologic defects. Relevant literature was analyzed to summarize characteristic cutaneous presentations and current diagnostic approaches, highlighting the importance of interdisciplinary evaluation. Results: Cutaneous findings in IEI encompass a wide spectrum of infectious, inflammatory, autoimmune, and neoplastic manifestations. Systematic classification of these lesions facilitates earlier recognition of underlying immune defects and supports differential diagnosis. Dermatologic signs frequently precede systemic manifestations, making them valuable early clinical indicators of IEI. Conclusions: Recognition of dermatologic manifestations is critical for early diagnosis of IEI. Interdisciplinary collaboration between dermatologists, immunologists, and other specialists improves diagnostic accuracy and patient management. Current therapeutic strategies range from symptomatic treatment to targeted therapies, and personalized approaches improve prognosis and quality of life in patients with IEI.