Small bowel (small intestine)
Infectious disorders
Entamoeba histolytica

Author: Hanni Gulwani, M.D. (see Authors page)

Revised: 14 February 2018, last major update August 2012

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Entamoeba histolytica small bowel

Cite this page: Gulwani, H. Entamoeba histolytica. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/smallbowelentamoeba.html. Accessed July 15th, 2018.
Definition / general
  • Dysentery causing protozoa that can also cause fulminant colitis; causes up to 100,000 deaths per year (Trop Biomed 2011;28:194)
  • Increased incidence in homosexual men and AIDS patients
Pathophysiology
  • Fecal oral spread
  • Amoeba invade colonic crypts, burrow into lamina propria, create flask shaped ulcer with broad base
  • 40% invade portal vessels, embolize to liver and cause abscesses up to 10 cm
  • May activate apoptosis in target cells (Trends Parasitol 2011;27:254)
  • Rare abscesses in lung, heart, kidneys, brain
Diagrams / tables

Images hosted on other servers:

Life cycle

Microscopic (histologic) images

Images hosted on other servers:

Various images



Images contributed by Dr. Hanni Gulwani:

Amoebic colitis, numerous trophozoites of amoeba are noted

Amoebic colitis, PAS stain