Entamoeba coli – Trophozoite

  • Common non-pathogenic commensal of human
  • Habitat in human: Large intestines
  • Trophozoites detected in faecal specimens of infected human
Diagnostic Features
  • Live parasites show sluggish movements
  • Size: 20 – 25 µm (range 15 to 50 µm) – larger than E. histolytica
  • Shape: Irregular with blunt pseudopodia
  • Nucleus: One nucleus; Peripheral chromatin granules: irregularly distributed & coarse
  • Large, usually eccentric karyosome in nucleus
  • Cytoplasm appears coarse, often with vacuoles
  • No RBCs in cytoplasm; Bacteria, yeast, etc., present
Magnification x10
Magnification x40
Magnification x100