- Entamoeba histolytica is a protozoan parasite that is the second leading cause of parasitic death, after malaria. The amoeba is acquired by the fecal-oral route. Cysts are commonly found in contaminated drinking water in tropical areas with poor sanitation.
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What is the meaning of Entamoeba histolytica cyst?
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How big is the trophozoite form of E.histolytica?
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Feb 09, 2020 · Entamoeba histolytica is a protozoan parasite that is the second leading cause of parasitic death, after malaria. The amoeba is acquired by the fecal-oral route. Cysts are commonly found in contaminated drinking water in tropical areas with poor sanitation.
- 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.
Infection with Entamoeba histolytica (and E.dispar) occurs via ingestion of mature cysts from fecally contaminated food, water, or hands. Beside above, is Entamoeba histolytica cyst dangerous? The most commonly infected organ is the liver, but Entamoeba abscesses have been found in the brain and lungs as well.
The infection can occur when a person puts anything into their mouth that has touched the feces of a person who is infected with E. histolytica, swallows something, such as water or food, that is contaminated with E. histolytica, or swallows E. histolytica cysts (eggs) picked up from contaminated surfaces or fingers.
Nov 19, 2020 · When your gut (intestines) becomes infected with the parasite Entamoeba histolytica (often shortened to E. histolytica), the condition is known as amoebiasis. It affects around 1 in 10 people, yet 9 out of 10 infected people show no symptoms. Discover treatment options, symptoms and how to prevent the spread of amoebiasis.
- Dr Laurence Knott