[Last Modified: ]
[Leishmania spp.]

Amastigotes of Leishmania are spherical to ovoid and measure 1-5 µm long by 1-2 µm wide.  They possess a large nucleus, a prominent kinetoplast, and a short axoneme, the last of which is rarely visible by light microscopy.  The organisms reside in macrophages of the host and can be found throughout the body.

A	B

A, B:  Leishmania spp. amastigotes; touch-prep stained with Giemsa.

A	B

A, B:  Leishmania tropica amastigotes from an impression smear of a biopsy specimen from a skin lesion.  In Figure A, an intact macrophage is practically filled with amastigotes (arrows), several of which have a clearly visible nucleus and kinetoplast; in Figure B, amastigotes are being freed from a rupturing macrophage.  Patient had traveled to Egypt, Africa, and the Middle East.  Based on culture in NNN medium, followed by isoenzyme analysis, the species was identified as L. tropica.