PARASITOLOGY: PROTOZOA

The only pathogenic ameba

• Entamoeba histolytica
• Entamoeba coli
• Endolimax nana
• Entamoeba gingivalis

SECONDARY AMEBIC MENINGOENCEPHALITIS

• Entamoeba histolytica
• Naegleria fowleri

PRIMARY AMEBIC MENINGOENCEPHALITIS

• Entamoeba histolytica
• Naegleria fowleri

TROPHOZOITES: Fine, centrally located karyosome, Endoplasm contains RBCs but no bacteria or cell detritus. Moves in one direction (unidirectional)

• Entamoeba histolytica
• Entamoeba coli

TROPHOZOITES: Large, eccentrically located karyosome, Endoplasm contain bacteria, yeasts, and cell detritus, Tries to move in several directions at the same time – sluggish motion

• Entamoeba histolytica
• Entamoeba coli

CYST: Coffin-shaped chromatoidal bars - Mature cyst with 4 nuclei

• Entamoeba histolytica
• Entamoeba coli

CYST: Splinter-like chromatoidal bars - Mature cyst with 8 nuclei

• Entamoeba histolytica
• Entamoeba coli

Blotlike karyosome; No chromatoidal bars and peripheral chromatin; May mimic D. fragilis, E. hartmann

• Iodamoeba butschlii
• Endolimax nana
• Entamoeba polecki
• Entamoeba hartmanni

Small-race E. histolytica; ID between E. histolytica/E. dispar is through size

• Iodamoeba butschlii
• Endolimax nana
• Entamoeba polecki
• Entamoeba hartmanni

Consistently uninucleated; chromatoidal bars are angular or pointed Endemic in Papua New Guinea

• Iodamoeba butschlii
• Endolimax nana
• Entamoeba polecki
• Entamoeba hartmanni