RESUMEN
Lucio phenomenon, or Lucio leprosy, is a rare severe lepra reaction that develops exclusively in patients with diffuse nonnodular lepromatous leprosy. It is characterized by irregular, angulated, or stellar necrotizing purpuric lesions that develop ulcerations. It mainly involves the extremities and develops as a result of massive invasion of vascular endothelial cells with lepra bacilli and secondary thrombotic vascular occlusion. Antiphospholipid antibodies often are detected in cases of Lucio phenomenon, and they are thought to play a role in its pathogenesis. We report a case of diffuse lepromatous leprosy in Egypt in which Lucio phenomenon with scrotal involvement and positive antiphospholipid antibodies was the first diagnostic presentation. The patient showed an excellent response to a combination of antileprotic treatment, low dose of prednisolone, acetylsalicylic acid, and anticoagulants. In addition, surgical debridement and vacuum therapy were performed for the scrotal lesion. Awareness of this grave presentation of leprosy is important for both dermatologists and rheumatologists to avoid misdiagnosis as vasculitis/collagen disease.