[Postinfectious Lucio phenomenon in diffuse leprosy. Report of 2 cases].

In the clinical classification of leprosy the diffuse nonnodular form belongs to the lepromatous subtype. In these patients only a diffuse cutaneous infiltration without nodules or plaques is seen. Although the cutaneous features can be difficult to identify, the reactional state in these cases may lead to a serious necrotizing vasculitis, known as Lucio's phenomenon. We describe two cases of Lucio's phenomenon triggered by erysipelas. The diagnosis of leprosy was established only after the immunologic reaction had occurred. Both patients were treated with steroids and thalidomide. In the second case, the bacterial infection led to sepsis and death. In at-risk patients with a necrotizing vasculitis, leprosy should be considered in the differential diagnosis.