Rare atypical feature of type II lepra reaction with ulcerative skin lesion in a lepromatous leprosy patient.

Lepra reaction is an acute exacervational status occurring in the chronic course of leprosy. Type 2 lepra reaction occur from multibacillus leprosy (such as BL or LL), which mediated by antigen-antibody immune complex deposited vasculitis, involving multiple organs, and usually associated with constitutional symptoms such as fever, malaise, joint pains. The skin lesions is characterized by painful and tender red papules or nodules on the skin, which also refers to erythema nodosum leprosum (ENL). Different rare atypical skin lesions of ENL have been reported such as bullous, ulcerative, necrotic, pustular, sweet syndrome like lesions in literature. The 74 years old male patient with lepromatous leprosy presented as multiple crusted ulcers on the trunk and red edematous nodule on extremities and face. The histopathologic feature was typical for type 2 lepra lesion. Fite stain revealed large histiocytes containing well defined dense granular bacillus. This case was very rare and interesting because of unusual crusted ulcerative skin lesions combined with conventional ENL lesions and leprosy itself is rare in Korea these days.