American cutaneous leishmaniasis is an important endemic zoonotic disease in the New World that comprises a spectrum of clinical manifestations. Diffuse cutaneous leishmaniasis (DCL) is a rare form of the disease characterized by antigen-specific immunodeficiency that often presents with multiple disfiguring non-ulcerated confluent nodules or plaques that involve large areas of the skin, resembling lepromatous leprosy. Relapse is invariable in advanced stages, despite aggressive chemotherapy, and a plethora of drugs has been tested with unchanging results. We report on a severe an exceptional case that resolved after treatment with amphotericin B, a drug considered only mildly effective, and discuss the therapeutic approach to this disease.