Entamoeba histolytica is an anaerobic parasitic amoebozoan, part of the genus Entamoeba. Predominantly infecting humans and other primates causing amoebiasis, E. histolytica is estimated to infect about 35-50 million people worldwide. E. histolytica infection is estimated to kill more than 55,000 people each year.
Amebiasis is a disease caused by the parasite Entamoeba histolytica. It can affect anyone, although it is more common in people who live in tropical areas with poor sanitary conditions. Diagnosis can be difficult because other parasites can look very similar to E. histolytica when seen under a microscope. Infected people do not always become sick.
- Causal Agents
- Life Cycle
- Geographic Distribution
Several protozoan species in the genus Entamoeba colonize humans, but not all of them are associated with disease. Entamoeba histolytica is well recognized as a pathogenic ameba, associated with intestinal and extraintestinal infections. Other morphologically-identical Entamoeba spp., including E. dispar, E. moshkovskii, and E. bangladeshi, are generally not associated with disease although investigations into pathogenic potential are ongoing. While the discussed species are morphologically-identical, E. histolytica may be observed with ingested red blood cells (erythrophagocytosis); E. dispar may occasionally be seen with ingested erythrocytes as well, although its capacity for erythrophagocytosis is much less than that of E. histolytica. Non-pathogenic amebae (e.g. Endolimax nana, Iodamoeba buetschlii, other Entamoeba species) are important because they may be confused with E. histolyticain diagnostic investigations.
Cysts and trophozoites are passed in feces . Cysts are typically found in formed stool, whereas trophozoites are typically found in diarrheal stool. Infection with Entamoeba histolytica (and E.dispar) occurs via ingestion of mature cysts from fecally contaminated food, water, or hands. Exposure to infectious cysts and trophozoites in fecal matter during sexual contact may also occur. Excystation occurs in the small intestine and trophozoites are released, which migrate to the large intestine. Trophozoites may remain confined to the intestinal lumen (A: noninvasive infection) with individuals continuing to pass cysts in their stool (asymptomatic carriers). Trophozoites can invade the intestinal mucosa (B: intestinal disease), or blood vessels, reaching extraintestinal sites such as the liver, brain, and lungs (C: extraintestinal disease). Trophozoites multiply by binary fission and produce cysts , and both stages are passed in the feces . Cysts can survive days to weeks in the extern...
Pathogenic Entamoeba species occur worldwide and are frequently recovered from fresh water contaminated with human feces. The majority of amebiasis cases occur in developing countries. In industrialized countries, risk groups include men who have sex with men, travelers, recent immigrants, immunocompromised persons, and institutionalized populations.
Entamoeba histolytica are pathogenic amoeba that are widely known for causing intestinal and extraintestinal infections in human beings. Entamoeba histolytica falls under the phylum Protozoa, the class Sarcodina and the order Lobosa.
May 26, 2021 · The cause of amebiasis is mainly the protozoan parasite Entamoeba histolytica. Life cycle of E. histolytica; SOURCE: CDC Amebiasis is a disease caused by infection with a parasitic amoeba that, when symptomatic, can cause dysentery and invasive extraintestinal problems. The cause of amebiasis is mainly the protozoan parasite Entamoeba histolytica.
Nov 19, 2020 · E. histolytica is an amoeba. An amoeba is the name given to any single-celled microscopic animal with a jelly-like consistency and an irregular, constantly changing shape. Amoebae are found in water, soil and other damp environments. They move and feed by means of flowing extensions of their body, called pseudopodia.
- Dr Laurence Knott
Entamoeba histolytica is an intestinal dwelling parasite in the human gastrointestinal tract that causes diseases such as amebiasis, amebic colitis and amebic liver abscesses. In most cases, E. histolytica colonizes the host's gut without causing symptoms or disease.
People also ask
Which Entamoeba species are pathogenic?
What is a parasitic amoeba?
What does Entamoeba mean?
What is the cyst of E. histolytica?
Entamoeba histolytica was first of all reported by a Russian Zoologist, Losch (1875), as Amoeba coli from the faeces of a patient suffering from dysentery. The genus Entamoeba was established by Cosagrandi and Barbagallo (1895); it should not, be confused with the genus Endamoeba which was established by Leidy (1879).
- related to: Entamoeba histolytica
hindawi.com has been visited by 10K+ users in the past month