Visceral Leishmaniasis
A 49-year-old previously healthy man presented to the emergency department with a 5-month history of fever, abdominal pain, fatigue, and an unintentional 15-kg weight loss. The physical examination was notable for an enlarged liver and spleen. Laboratory studies showed a white-cell count of 2040 per cubic millimeter (reference range, 4000 to 10,000), a hemoglobin level of 9.2 g per deciliter (reference range, 14.0 to 18.0), and a platelet count of 50,000 per cubic millimeter (reference range, 140,000 to 400,000). Blood cultures as well as tests for human immunodeficiency virus, hepatitis B virus, hepatitis C virus, cytomegalovirus, and Epstein–Barr virus were negative. Computed tomography of the abdomen confirmed the presence of an enlarged liver and markedly enlarged spleen (Panel A). Examination of a bone marrow aspirate revealed amastigotes, each with a nucleus (Panel B, blue arrow) and a kinetoplast (Panel B, red arrow), within histiocytes. This is the typical appearance of leishmaniasis, and polymerase-chain-reaction testing of the bone marrow aspirate confirmed the diagnosis. Transmitted by sandflies, Leishmania infantum is endemic to Italy and the Mediterranean region. The patient started treatment with liposomal amphotericin B. At a follow-up visit 1 month later, the fever, abdominal pain, and fatigue had resolved, and physical examination revealed resolution of the splenomegaly.