Entamoeba histolytica (cont)
TROPHOZOITE
SIZE: 11 to 60 mcm.
SHAPE : Irregular.
NUCLEUS: Vesicular, dispersed.
NUMBER: One.
PERIPHERAL CHROMATIN: Finely granular and evenly distributed.
KARYOSOME: Small, discrete, and usually centrally located.
NUCUEOPLASM Clean.
CYTOPLASM: Clean.
APPEARANCE: Finely granular.
INCLUSIONS: Occasional RBCs.
MOBILITY: Directional and progressive with finger-like pseudopodia.
CYST
SIZE: 11 to 20 mcm.
SHAPE : Spherical.
NUCLEUS:
NUMBER: One to four; the mature cyst has four.
PERIPHERAL CHROMATIN: Finely granular and evenly distributed.
KARYOSOME: Small, discrete, and usually centrally located.
NUCUEOPLASM Clean.
CYTOPLASM: Finely granular.
CHROMATOID BODIES: If present, cigar-shaped, rounded ends; diagnostic
feature.
GLYCOGEN: Diffused, in vacuoles for young cysts.
Figure 1-5. Stages of E. histolytica.
MD0842
1-8