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Updated: Dec 6, 2025

Dermoscopy Aids in the Diagnosis of Discoid Lupus Erythematosus
Published on: May 16, 2025
Case for diagnosis. Hyperpigmented and excoriated papules and nodules in a diabetic patient
Catalina Hasbún1, Mauricio Sandoval2, Sergio González-Bombardiere3
1School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
Abstract:
Reactive perforating collagenosis is a rare perforating dermatosis clinically characterized by intensely pruritic hyperpigmented papules, plaques, and nodules with a central keratotic plug. Histopathology reveals transepidermal elimination of collagen fibers. Its pathophysiology is still under investigation, but the acquired form has been linked to systemic conditions such as diabetes mellitus and chronic kidney disease. However, it has also been described as a paraneoplastic syndrome. The authors present the case of a 65-year-old diabetic patient in which a myeloproliferative neoplasm was suspected.
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