Lucio phenomenon is a rare vasculopathy that can occur in patients with Hansen disease, particularly diffuse lepromatous leprosy. It is characterized by retiform purpura and necrotic ulcerations, most commonly affecting the extremities. Diagnosing Lucio phenomenon can be challenging, especially when secondary bacterial infections occur. We report a patient with Lucio phenomenon who presented with acute necrotizing fasciitis of his left upper extremity and a 10-year history of chronic ulcerations. Shortly following admission, he also developed acute kidney injury. The necrotizing fasciitis was treated with prompt surgical debridement and intravenous antibiotics. Biopsy and PCR of a right upper extremity ulcer confirmed the presence of Mycobacterium lepromatosis. Multidrug therapy and prednisone were used to treat the Lucio phenomenon. After initiating treatment, no new lesions developed, kidney function improved, and the patient underwent successful skin graft of his left upper extremity. Although corticosteroid use is controversial, our patient's marked response to multidrug therapy with prednisone highlights the importance of this regimen in severe presentations of Lucio phenomenon. To the best of our knowledge, only two other cases of Lucio phenomenon confirmed to be caused by M. lepromatosis have been reported in living patients (rather than retrospectively identified post-mortem), underscoring the importance of the presented clinical course and treatment regimen.
