Visceral leishmaniasis — DTM&H MCQ

Correct answer: D — Visceral leishmaniasis

The correct answer is D, visceral leishmaniasis. This man from Bihar, an area of Indo-Gangetic plain hyperendemic for kala-azar, has the classic triad of prolonged fever, weight loss and massive splenomegaly, accompanied by pancytopenia (anaemia, neutropenia and thrombocytopenia) from bone marrow infiltration and hypersplenism. Visceral leishmaniasis is caused by Leishmania donovani transmitted by sandfly bites, and Bihar accounts for the majority of the global disease burden, making geography a key discriminator here. The combination of geography, chronicity and trilineage cytopenia with massive splenomegaly is the pattern taught for kala-azar and should prompt splenic or bone marrow aspirate for amastigotes or rK39 serology. Why the other options are wrong: C. Chronic schistosomiasis: causes portal hypertension and splenomegaly from periportal fibrosis, but does not produce this degree of pancytopenia or prolonged fever, and Bihar is not a schistosomiasis-endemic focus. A. Hyperreactive malarial splenomegaly: occurs after repeated malaria exposure with massive splenomegaly and anaemia, but neutropenia and thrombocytopenia this severe are unusual, and fever is typically absent between episodes, unlike this patient's ongoing 2-month febrile illness. E. Disseminated strongyloidiasis: presents with gastrointestinal and pulmonary symptoms plus eosinophilia in immunosuppressed hosts, not massive splenomegaly with pancytopenia. B. Enteric fever relapse: causes fever and modest splenomegaly but not massive splenomegaly, and typically shows leucopenia rather than the marked trilineage cytopenia seen here. Key point: massive splenomegaly with pancytopenia and weeks of fever in a patient from Bihar is visceral leishmaniasis until proven otherwise.

Reference: UK Health Security Agency, Leishmaniasis (visceral leishmaniasis / kala-azar): epidemiology and clinical features, researchportal.ukhsa.gov.uk