The kinetoplast in the diagnosis of visceral leishmaniasis

In visceral leishmaniasis (as in all leishmanial infections), microscopic diagnosis is made by observing the intracellular amastigote form, complete with a kinetoplast, in aspirate smears or biopsied tissue. In the 2 clinically-ill patients described here, intracellular inclusions were demonstrated in a bone marrow aspirate or a colon tissue biopsy. Kinetoplasts associated with the inclusions were not identified in the marrow aspirate smear (although the patient was treated for visceral leishmaniasis), but were identified retrospectively in the colonic tissue (although the patient was treated for histoplasmosis). Both cases illustrate the importance to clinical consultants of microscopically observing (or not) an associated kinetoplast when faced with a tissue aspirate or biopsy specimen showing intracellular inclusions.