Entamoeba histolytica – Cyst

  • Cyst is the infective stage to human
  • Cysts detected in faecal specimens of infected human
Diagnostic Features
  • Shape: Spherical
  • Size: 12 – 15 mm (range 10 – 20µm)
  • Nuclei: Mature cyst contains 4 nuclei;
  • Centrally located small karyosome in nucleus; Peripheral chromatin is fine and uniformly distributed
  • Chromatoid bodies with bluntly rounded ends may be present in cytoplasm
  • Glycogen mass: Diffused or absent in mature cysts; clumped in immature cysts

Magnification x10

Magnification x40

Magnification x100