The enduring value of bone marrow morphology in kala-azar amid molecular distractions

We report a case of a 35-year old woman with prolonged fever, cytopenia and massive splenomegaly, initially misdiagnosed as steroid-refractory auto-immune haemolytic anaemia with thrombocytopenia. Whole-exome sequencing revealed pathogenic variants in three genes, none of which explained the clinical picture. A subsequent bone marrow examination identified Leishman-Donovan bodies, confirming visceral leishmaniasis (VL). This case illustrates the pitfalls of over-reliance on next-generation sequencing and immunologic tests in the absence of a clear clinical hypothesis. In cost-conscious healthcare settings such as India, simpler and less expensive diagnostic modalities, such as bone marrow microscopy, remain crucial, especially for endemic infections such as VL. High-end molecular diagnostics should be interpreted with caution, with clinical correlation and an awareness of the limitations and incidental findings common to such testing.