pathogenesis
Last reviewed 01/2018
The organisms exists as a motile trophozoite and a cyst. The cyst can survive outside the body and can be transmitted to humans via ingestion of contaminated food or water. It may also be spread directly by person-to- person contact. Whilst the cysts are in the small intestine, the trophozoites emerge, pass down into the colon and then multiply.
In many cases individuals may carry the pathogen without evidence of clinical disease. In other instances the trophozoites will invade the colonic epithelium and continually multiply. This results in ulceration of the mucosa and the trophozoites may then migrate into the portal vein and then onto the liver. Infection of the liver may result in hepatitis and the formation of intrahepatic abscesses. If this disease is invasive then it may result in death if not treated promptly.
The incubation period varies from a matter of days to up to a year.