Idiopathic atrophie blanche.

A 41-year-old woman presented with a 3-year history of purpuric lesions followed by superficial, painful ulcers and development of lesions on the lower legs and on the dorsa of the feet, particularly in the summer. The patient was asymptomatic during the winter months. On physical examination she had irregular, scleroatrophic, white-ivory, coalescent lesions on a livedoid basis, with purpuric and, in some lesions, pigmented borders with numerous telangiectatic capillaries. These lesions were localized on the medial sides of the lower legs and on the dorsa of the feet (Figure 1). Laboratory investigations were normal or negative, including complete blood cell count, platelets, coagulation indexes, erythrocyte sedimentation rate, serum immunoglobulins, antinuclear antibodies, anti-double-stranded DNA, anticardiolipin, antiphospholipids, antineutrophilic cytoplasmic antibodies, circulating immunocomplexes, complement fractions (C3, C4), cryoglobulins, rheumatoid factor, and Rose-Waaler reaction. The only laboratory abnormality was an elevated fibrinogen level (472 mg/dL). Doppler velocimetry excluded a chronic venous insufficiency. Thoracic x-ray and abdominal ultrasound were normal. A digital photoplethysmograph revealed functional Raynaud's phenomenon. A biopsy specimen taken from a purpuric lesion showed an atrophic epidermis with parakeratosis and focal spongiosis. An increased number of small-sized vessels were observed within a sclerotic dermis. Most of the vessels in the upper dermis were dilated and showed endothelial swelling; some were occluded due to amorphous hyaline microthrombi (Figure 2). There were fibrinoid deposits around the vessels with thickening of the vessel walls. Extravasated erythrocytes were found throughout the upper and mid-dermis. There was a sparse perivascular lymphocytic infiltrate but no vasculitis. Direct immunofluorescence showed a perivascular microgranular deposit of IgM (+), C3 (++), and fibrinogen/fibrin (+++). On the basis of clinical, serologic, histopathologic, and immunopathologic findings, a diagnosis of idiopathic atrophie blanche was made. The patient was treated with dapsone (50 mg p.o. q.d.) and pentoxifylline (400 mg p.o. t.i.d.) with pain relief and complete resolution of the ulcerations after 6 weeks of therapy.