Ameba

• Protozoa - Unicellular eukaryotes
• phylum - sarcomastigophora
• subphylum - sarcodina
• class - lobosea
• Mostly distinguished from other protozoa by their size, structure, and other traits, such as how they move.
• Has the ability to extend their cytoplasm in the form of pseudopods, which allows them move within their environment
• Two morphologic forms:

  • cyst
  • trophozoite
• cyst - infective form
• cyst - has thick cell wall
• Trophozoite- Reproducing/multiplying form
• Trophozoite - Can be easily destroyed by gastric juices
• Free living

  • Entamoeba gingivalis
  • Naegleria fowleri
  • Acanthamoeba spp.
• Entamoeba histolytica- Only pathogenic intestinal ameba
• Entamoeba histolytica- Most invasive of the genus
• Entamoeba histolytica

  MOT:

  • Ingestion
  • fecal-oral
  • unprotected sex
• Entamoeba histolytica- Infection often associated with Charcot-Leyden Crystals
• Entamoeba histolytica

  Associated with:

  • Intestinal amebiasis
  • Amebic colitis
  • Amebic Dysentery
  • Amebic liver abscess (ALA)
  • Secondary amebic meningoencephalitis (SAM)