Predictors of Immunosuppressive Treatment in Cutaneous Arteritis: Analysis of Clinical Characteristics in 42 Patients.

Cutaneous arteritis is a necrotizing vasculitis of medium-sized vessels in the skin for which no established criteria exist to guide the initiation of systemic treatment. This study aimed to identify the clinical and laboratory markers associated with the initiation of immunosuppressive treatments, including systemic corticosteroids. This retrospective chart review included 42 patients with cutaneous arteritis treated at the Department of Dermatology, Yokohama City University Hospital, from 2010 to 2023. Clinical manifestations and laboratory and imaging data were collected. Univariable and multivariable analyses were performed to identify the risk factors associated with the initiation of immunosuppressive treatment. Twenty-five patients with cutaneous arteritis (five men, 20 women) were included in this study. Of these, 14 patients received systemic corticosteroids and 11 were treated with additional immunosuppressive drugs. The Youden index analysis indicated that the thresholds of systemic corticosteroid induction were patients older than 43 years and platelet counts more than 340 000/μL. Univariable Firth logistic regression analysis showed numbness in the lower limbs, older age at onset, elevated platelet counts, and D-dimer levels (≥ 1 μg/mL) as risk factors for systemic corticosteroids. Our analysis identified several risk factors, such as numbness in the lower limbs, that may help predict the need for immunosuppressive treatment. Further large-scale prospective studies are required to confirm these findings.