Supplementary Material for: Acquired Reactive Perforating Collagenosis Complicated by Diabetes Mellitus and Hypertension: A Case Report

A 55-year-old male with a 15-year history of diabetes mellitus and hypertension presented with a two-month history of progressive pruritic papules and nodules on both lower limbs. Despite initial misdiagnosis and unsuccessful antifungal therapy, dermatoscopic and histopathological evaluations confirmed acquired reactive perforating collagenosis (ARPC), a rare condition often associated with systemic diseases. This case underscores the diagnostic challenges of ARPC and highlights the importance of integrating dermatoscopy and histopathology to differentiate it from other perforating or pruritic dermatoses. Notably, the coexistence of diabetes and hypertension in this patient aligns with the recognized association between ARPC and metabolic disorders, emphasizing the need for comprehensive systemic evaluation in similar presentations. Symptomatic treatment with topical retinoic acid cream led to significant improvement, demonstrating a practical therapeutic approach in resource-limited settings. This report contributes to the limited literature on ARPC by illustrating its clinical, dermatoscopic, and histopathological features in the context of common comorbidities, reinforcing its relevance for dermatologists and internists alike.