Stasis dermatitis and pigmented purpuric dermatoses: Histological characterization and review of literature

Abstract

Abstract Background Stasis dermatitis and pigmented purpuric dermatoses can both manifest as hyperpigmentation, petechiae and/or purpura on the lower extremities, posing a challenge for macroscopic differentiation. We investigated the histological differences in these two conditions. Objectives To determine the histological characteristics of stasis dermatitis and pigmented purpuric dermatosis. Methods Skin biopsy specimens were obtained from seven patients with stasis dermatitis, 15 with pigmented purpuric dermatosis, and three control patients. The samples were analysed for histological changes (hematoxylin‐eosin), melanin (silver nitrate), iron, elastic stain, and with an immunohistochemistry for melanocytes (Melan‐A). Results The predominant histological features of stasis dermatitis were hemosiderin deposits, eosinophils and telangiectasias. Pigmented purpuric dermatosis was characterized by extensive erythrocyte extravasation, interface changes and spongiosis. Conclusions The distinct histological characteristics of stasis dermatitis and pigmented purpuric dermatosis can improve the diagnostic classification of these entities.

Keywords

• hemosiderin
• hyperpigmentation
• melanin
• pigmented purpuric dermatoses
• Schamberg's disease
• stasis dermatitis