Visceral leishmaniasis and lymphoma: a rare and dangerous couple

Leishmaniasis is a parasitic disease caused by protozoa of the genus Leishmania. The vectors are hematophagous (blood-feeding) dipterans of various genera, with humans serving as accidental definitive hosts and, in some cases, as reservoirs. Visceral leishmaniasis more often affects immunocompromised individuals, in whom the protozoan invades and replicates within the host’s macrophages, evading innate and cell-mediated immune responses. We describe the case of a 54-year-old male patient who had not traveled to endemic areas. He presented with progressive asthenia associated with persistent fever, which had been treated at home with nonsteroidal anti-inflammatory drugs and oral betamethasone. During hospitalization, he developed cytopenia and hepatosplenomegaly. Bone marrow biopsy revealed the presence of Leishmania and intravascular large B-cell lymphoma. When faced with cases of fever of unknown origin, clinicians should also investigate opportunistic infections. An underlying condition causing immunosuppression may not be clear, and corticosteroids often alter hematological values, thus masking a hematological disease.