Entamoeba histolytica
Dongyou Liu in Handbook of Foodborne Diseases, 2018
Amoebiasis is a parasitic infection caused by Entamoeba histolytica; it has a great impact on public health, especially in developing countries. It is estimated that E. histolytica causes 50 million cases of disease and 40,000–100,000 deaths per year2; however, many aspects of the host-parasite relationship are still poorly understood. Intestinal amoebiasis (IA) affects the large intestine and is related to several clinical states. Amoebic ulcerative colitis is a well-defined medical infection, but other less common disorders include amoebic fulminating dysentery, amoeboma, and amoebic appendicitis. Amoebic liver abscess (ALA) is the most frequent extraintestinal form of amoebiasis and is characterized by large areas of liver necrosis or by abscesses.3 As humans are the main sufferers of amoebiasis, it is essential to review aspects of the parasite's cell biology and life cycle as well as clinical aspects and the epidemiology, pathogenesis, diagnosis, and treatment of this disease. Further knowledge of E. histolytica and of host responses of amoebiasis would help elucidate many aspects of this illness. In this chapter, we highlight the use of in vitro and in vivo models to understand the pathology and to facilitate more effective and earlier diagnosis. New protocols for the treatment of amoebiasis are needed to prevent side effects.
Protozoa
Loretta A. Cormier, Pauline E. Jolly in The Primate Zoonoses, 2017
Entamoeba histolytica is a gastrointestinal parasite spread through the fecal-oral route through ingestion of contaminated food or water (Petri and Rashidul 2015). Approximately 80% of the cases are asymptomatic, and when symptoms appear, they are often mild with diarrhea (CDC 2015a). However, in some cases, amebic dysentery may develop with more severe symptoms of bloody diarrhea, amebic colitis, and liver abscess (Petri and Rashidul 2015). Approximately 34–50 million symptomatic cases occur worldwide each year with approximately 100,000 deaths (Petri and Rashidul 2015). It is most common in tropical areas of the developing world and associated with poverty and poor sanitation (CDC 2015a). Young children and immunocompromised individuals are most at risk (Petri and Rashidul 2015).
Nutritional Disorders/Alternative Medicine
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss in Understanding Medical Terms, 2020
Food poisoning involves gastrointestinal symptoms after consumption of foods or drink, usually due to salmonella or an enterotoxin. Foods, water or milk can also be carriers for the enteric (intestinal) fevers—typhoid or paratyphoid—caused by Salmonella organisms. Bacillary dysentery (Shigella) and cholera (Vibrio cholerae) are other bacterial diseases spread through food or drinking water. Amebic dysentery, caused by the protozoan Entamoeba histolytica, is transmitted by water or uncooked foods contaminated with human feces. The term traveler's diarrhea refers to the gastrointestinal disorder that occurs from strains of enterobacteria to which immunities have not been developed.
The impact of water crises and climate changes on the transmission of protozoan parasites in Africa
Published in Pathogens and Global Health, 2018
Shahira A. Ahmed, Milena Guerrero Flórez, Panagiotis Karanis
Entamoeba spp., were presented in ten African countries (Zimbabwe, Tunisia, Sudan, Nigeria, Morocco, Ethiopia, Egypt, Cote d´Ivoire, Cameroon, Burkina Fasso). Diarrhea and dysentery are the most common symptoms after infection with this parasite. Extra-intestinal complications are less frequent to occur; however, high mortality can be associated. In recent cross sectional study in South Africa, E. histolytica was highly loaded in the diarrhea samples [40]. In Ethiopian patients, Entamoeba spp. were the highest predominant protozoa in the diarrhea samples from adults [41] and one of the most identified parasites in children under five years [42]. In Cameroon, Egypt and Sudan, Entamoeba spp., were detected in drinking water [42–44]. Direct wet mount/iodine is a simple, cost effective popular method used in African reports to identify cysts of Entamoeba spp. in water samples which probably raises its reporting numbers.
The management of Babesia, amoeba and other zoonotic diseases provoked by protozoa
Published in Expert Opinion on Therapeutic Patents, 2023
Clemente Capasso, Claudiu T. Supuran
Entamoeba histolytica is a pseudopod-forming, non-flagellated protozoan parasite that can cause amebiasis when a person becomes infected with it [35]. Amebiasis is more prevalent in those countries with tropical and subtropical locations and poor sanitation (Africa, Mexico, parts of South America, and India), although everybody may be at risk [36,37]. When viewed through a microscope, certain parasites can appear strikingly similar to E. histolytica, making diagnosis rather challenging [35]. Amebiasis can cause no symptoms at all, or it can progress to a severe illness characterized by amebic colitis (inflammation of the colon) and amebic liver abscess [36]. In the developing world, where diarrhea is the third largest cause of mortality among children under the age of 5 (accounting for 9% of all fatalities in this age group), amebic colitis is one of the top 15 causes of diarrhea in the first two years of life [36,38]. Fulminant amebic colitis is the most severe and life-threatening complication of amebiasis, presenting with bloody diarrhea, fever, leukocytosis, and stomach pain. Necrosis, toxic megacolon, perforation, and peritonitis may also occur [39].
Association of Helicobacter pylori and protozoal parasites in patients with chronic diarrhoea
Published in British Journal of Biomedical Science, 2018
J Yakoob, Z Abbas, R Khan, K Tariq, S Awan, MA Beg
In developing countries, co-infections with different pathogens are common, and are attributable the feco-oral transmission of bacterial and parasite pathogens brought about by the poor quality of the water consumed by the population at large living in unhygienic conditions, i.e. overcrowding, poor toilet facilities, and absence of quality health care [1]. The prevalence of intestinal parasites such as Blastocystis sp, Giardia duodenalis and Entamoeba sp., etc. has been estimated as 53% in children residing in an urban slum of a metropolitan city of Karachi, Pakistan [2]. Symptoms of abdominal discomfort and or pain, nausea and irregular bowel habit such as diarrhoea are associated with Entamoeba histolytica, Blastocystis sp and G. duodenalis infection. Amoebiasis is a faecal-oral route transmitted infection with the amoebas of the Entamoeba group. The symptoms of amoebiasis vary in severity from mild to severe and include loose stools, abdominal cramping, and abdominal pain. These are usually associated with infection by E. histolytica, but there are also reports of Entamoeba moshkovskii infection [3,4]. Microscopically, E. moshkovskii, Entamoeba dispar and E. histolytica are indistinguishable and require PCR test using specific primers for differentiation.
Related Knowledge Centers
- Amoebic Liver Abscess
- Commensalism
- Dysentery
- Entamoeba Coli
- Entamoeba Gingivalis
- Entamoeba Histolytica
- Escherichia Coli
- Gastrointestinal Tract
- Parasitism
- Amoebiasis