Progressive Pigmentary Purpura (Schamberg's Disease)

Flat, tan-pink patches on his lower legs disturbed a 52-year-old man. The lesions had visible, nonpalpable petechiae, which did not blanch on diascopy; telangiectasia and inflammatory vasodilation, therefore, were excluded from consideration.

Complete blood cell count, platelet count, erythrocyte sedimentation rate, and protein electrophoresis were normal. Proteinuria was absent. There was no gross evidence of superficial varicosities. The normal laboratory findings confirmed the diagnosis of progressive pigmentary purpura, or Schamberg's disease.

Dr Yehia Y. Mishriki of Allentown, Pa, writes that Schamberg's disease is one of the pigmented purpuric dermatoses, which includes Majocchi's disease and lichen aureus. These dermatoses more commonly occur in men and usually appear between the ages of 30 and 60. The cause is unknown, but it is believed to begin with an immunologic cell-mediated injury to the wall of small capillaries that leads to extravasation of erythrocytes.

The pinpoint petechiae are areas of fresh hemorrhage; older lesions are tan to brown and are caused by deposition of hemosiderin. Infrequently, the petechiae may be palpable.

Treatment is not necessary, unless cosmetics is a concern. Topical low- and mid-strength corticosteroids prevent new lesions; older lesions may fade after many months or years. Oral tetracycline or minocycline may be helpful. Reserve psoralens plus ultraviolet A (PUVA) for the most severe forms of the disease.