Diagnosis: Schamberg’s disease
Schamberg’s disease is a form of progressive pigmented purpuric dermatosis. This type of nonpalpable purpura consists of reddish-brown macules that are usually located on the lower extremities and ankles, and spare the soles of the feet. These petechiae appear due to capillary leakage and breakdown of blood near the skin surface, leaving behind hemosiderin deposits.
Clinically, the lesions are asymptomatic and may persist for months or years. They are characteristically referred to as punctate "cayenne pepper" spots, and can vary in size and shape. Occasionally, mild erythema and scaling can cause slight itching.
Although these lesions have a vasculitic appearance, there is no hematologic or other internal disease association. Schamberg’s purpura may resemble stasis dermatitis, because both processes include inflammation, dilation of capillaries, extravasation of erythrocytes, and hemosiderin deposits. However, lesions due to venous insufficiency extend deep into the dermis and have more pronounced epidermal changes and dermal fibrosis.
An unknown cause. Although no one knows what causes Schamberg’s disease, a cellular immune reaction may be at work. Early endothelial expression of certain intracellular adhesion receptors has shown a common pericapillary infiltrate pattern in cases of Schamberg’s disease.1 Recent viral infection and allergic reactions to medications, such as aspirin, have also been associated with Schamberg’s disease.2