This site is intended for healthcare professionals

2288 pages added, reviewed or updated during the last month (last updated: 19/4/2021)

2288 pages added, reviewed or updated during the last month (last updated: 19/4/2021)

Medical search

amoebic dysentery

FREE subscriptions for doctors and students... click here
You have 3 more open access pages.

Amoebic dysentery is caused by Entamoeba histolytica, which is most often acquired in the tropics.

The organism invades the colonic mucosa creating shallow ulcers with undermined edges.

  • Reservoir - Humans are the only known reservoir

  • Epidemiology - Infections occur worldwide but are endemic in countries with poor sanitation; most UK cases are imported by travellers to endemic areas

  • Transmission - Main route is through ingestion of contaminated food or water. Person-to-person transmission may also occur between household and sexual contacts via faecal-oral route

  • Incubation period - Usually 2-4 weeks but may last months to several years

  • Clinical features - 90% of cases are asymptomatic
    • diarrhoea with or without dysentery occurs in intestinal disease- symptoms are often few or mild, with loose stools, mucus and blood - however may lead to fulminating colitis
    • complications of this condition include severe colitis, perforation, localised amoeboma and liver abscess.
      • amoebic liver abscess may occur which can be fatal

  • Period of infectiousness - cases are considered infectious as long as cysts continue to be excreted which may last several years


  • confirmation via PCR is important to distinguish between E. histolytica and non-pathogenic strains e.g. E. dispar


  • PHE (2019). Recommendations for the Public Health Management of Gastrointestinal Infections

Last edited 02/2020