Entamoeba histolytica is the pathogen responsible for invasive amoebiasis which includes amoebic dysentery and amoebic liver abscesses. Fecaloral route, either by eating or drinking fecally contaminated food or water or persontoperson contact such as by diaper changing or sexual activity. Some morphologic features of the organisms in this case were not easily seen, possibly because of the medication or poor specimen preservation. Entamoeba histolytica is an invasive, pathogenic protozoan, causing amoebiasis, and an important cause of diarrhea in developing countries. This kind of protozoan parasite resides in the mucous and submucous layer of the large intestine specially. The protozoan parasite, entamoeba histolytica, is the causative agent of amoebiasis in humans.
First molecular epidemiology of entamoeba histolytica, e. Entamoeba histolytica infections are commonly observed in tropical and subtropical regions of the world including iran. Entamoeba histolytica is an anaerobic parasitic protozoan, part of the genus entamoeba. The epidemiology of infection with entamoeba histolytica in the. Therefore as far back as in 1925 a concept of the existence of two morphologically identical amoeba species was formulated brumpt 1925. Pdf the epidemiology of entamoeba histolytica infection in sudan is poorly understood. It is the cause of amebic dysentery bloody diarrhea as well as colonic ulcerations.
Pathogenesis and immune response toward entamoeba histolytica. Entamoeba histolytica is a an anaerobic parasitic protozoan that is responsible for the development of amoebiasis. A countrywide stool survey of the gambia showed the prevalence of entamoeba histolytica cysts to range from. Entamoeba histolytica and entamoeba dispar basic guidelines a. Intestinal and extraintestinal are the two forms of amoebiasis. Laboratory diagnostic techniques for entamoeba species clinical. Predominantly infecting humans and other primates causing amoebiasis, e. Clinical manifestations of amebic infection range widely from asymptomatic to severe symptoms, including dysentery and extraintestinal abscesses. It exists in two formsthe trophozoite which is the active, dividing form, and the cyst which is dormant and can survive for prolonged periods outside the host. Entamoeba histolytica is an invasive, pathogenic protozoan. Entamoeba histolytica is a protozoan parasite and the causative agent of amebiasis. Entamoeba histolytica is an enteric protozoan parasite with worldwide distribution. Safety precautions for working with entamoeba histolytica entamoeba histolytica causes dysentery in humans and can also cause amoebic liver abscess, which can be fatal if untreated.
It causes intestinal and extraintestinal amoebiasis. In endemic developing countries where resources are limited, microscopic examinations based on wheatley trichrome staining is commonly used for. Further molecular studies have identified a third species, e. Identification of entamoeba histolytica trophozoites in. In 1984, at least 40,000 deaths were attributed to amoebiasis. It is estimated approximately 1% of humans are infected with e.
The protozoan parasite entamoeba histolytica, possibly other entamoeba spp transmission. To maximize recovery of cysts, stool samples in formalin, or other fixatives, should be concentrated prior to microscopic examination e. Pdf understanding the epidemiology of entamoeba histolytica. House flies and cockroaches mechanical transmission. It feeds mainly on the tissues of the intestinal wall. Amoebiasis is a major problem in developing countries. Entamoeba histolytica, a protozoan parasite, is the etiologic agent of amoebiasis in humans. Entamoeba histolytica causes about 50 million infections worldwide with a death rate of over 100,000 annually. Most cases of dysentery will subside on their own, but illness can recur if left untreated.
The bacteriocin inhibited the growth of parasite were 36. Entamoeba histolytica belongs to the genus entamoeba, and it is an important human pathogen. The epidemiology of entamoeba histolytica has been complicated by the mid1990s redescription of e. Entamoeba histolytica and another ameba, entamoeba dispar, which is about 10 times more common, look the same when seen under a microscope. A casecontrol study was conducted among residents of hanam province, northern. Entamoeba histolytica is a pathogenic parasite in the intestine of human beings and many other primates. Entamoeba histolytica is a protozoan parasite that causes amebic dysentery and liver abscess. Progress in the epidemiology of amoebiasis has not only suffered from.
Entamoeba histolytica an overview sciencedirect topics. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. In most infected individuals the trophozoites exist as commensals. Entamoeba histolytica modes of transmission human being is the principle host source of infection. Multiple stool samples at least 3 should be tested before a negative result is reported. Picmonic is research proven to increase your memory retention and test scores. Molecular epidemiology and drug resistance study of entamoeba. Learn entamoeba histolytica protozoa microbiology picmonic for medicine faster and easier with picmonics unforgettable images and stories. Worldwide, approximately 50 million people develop colitis or extraintestinal disease, with over 100,000 deaths annually 3. Entamoeba histolytica is a protozoan parasite that causes amoebiasis. Hostparasite interactions in entamoeba histolytica and entamoeba dispar. For this purpose, we performed the genotyping of entamoeba isolates and the. Entamoeba histolytica, the causative agent of amebiasis, is a protozoan parasite that accounts for an estimated 100,000 annual deaths globally. Recent studies have revealed opportunities to produce an effective vaccine against the entamoeba histolytica infection.
Research article open access entamoeba histolytica and. Life history of entamoeba histolytica parasitology. Safety precautions for working with entamoeba histolytica. Prevention and control of amoebic dysentery in hong kong. Entamoeba histolytica introduction there is a large number of species of amoebae which parasitise the human intestinal tract. Molecular differentiation of entamoeba histolytica. It was not until 1993 that diamond and clark 1993 gave the ultimate redescription of e. Pathogenesis of infection by entamoeba histolytica. General description entamoeba histolytica is an ameba that feeds on cells in the human colon.
The structure and life cycle of entamoeba with diagram. Ingestion of contaminated food or water with amoebae cyst infective stage. The highest prevalence of amebiasis is in developing countries where barriers between human feces and food. Amoebiasis continues to be a major cause of morbidity and mortality in children in developing countries.
Infection ranges from mostly asymptomatic colonization of the large bowel to invasive and potentially fatal intestinal and extraintestinal disease, with a special predilection for liver abscess formation. Oti and others published understanding the epidemiology of entamoeba histolytica infections find, read and cite all the research. It inhabits the mucous and submucous layers of the large intestine. The study objective was to assess risk factors of e. This was a case of amebiasis caused by entamoeba histolyticadispar. Entamoeba histolytica is an important protozoan intestinal infection in resourcepoor settings, including vietnam. Previously, it was thought that 10% of the world population. Entamoeba histolytica is an invasive enteric protozoan parasite that is the cause of amebiasis. Number of entamoeba histolytica parasites in bacteriocin, supernatant, metronidazole and control groups. Some important species of entamoeba are described below.
Entamoeba histolytica is a protozoan endoparasite inhabiting the mucosa and submucosa layers of the large intestine of human beings, causing dysentery and liver abscess. Amebiasis is caused by entamoeba histolytica see the image below, a protozoan that is found worldwide see etiology. The genus entamoeba was established by leidy in 1879. Intestinal amebiasis is caused by the protozoan entamoeba histolytica.
It is responsible for amoebic dysentery bloody diarrhea and invasive extraintestinal amebiasis such as liver abscess, peritonitis, pleuropulmonary abscess. Our understanding of its epidemiology has dramatically changed since this amoeba was distinguished from another morphologically similar one, entamoeba dispar, a non. The main objectives of the present work were to determine the molecular frequency and the dynamic of infection of e. Over the same period it has also become clear that the true incidence of e. Entamoeba histolytica is an anaerobic parasitic amoebozoan, part of the genus entamoeba. According to the best estimates walsh 1986 approximately 48 million individuals suffer from amoebiasis throughout the world. Entamoeba histolytica amebiasis infectious disease and.
Entamoeba coli life cycle and location identical to. Others such as entamoeba coli not to be confused with escherichia coli and entamoeba dispar are harmless. To investigate the molecular epidemiology of entamoeba histolytica. Although many people harbour this organism world wide, only about 10% develop clinically. In this article we will discuss about the life history of entamoeba histolytica explained with diagram. It contains four nuclei when mature, one nucleus when immature with glycogen in a. Overexpression of differentially expressed genes identified in nonpathogenic and pathogenic entamoeba histolytica clones allow identification of new pathogenicity factors involved in amoebic liver abscess. Pdf epidemiology of entamoeba infection in sudan researchgate. Risk factors for entamoeba histolytica infection in an.
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