This essay is a comprehensive review on the pathogenic and potentially athogenic amoebae,. The morphological differences between intestinal types as well as the free living types were clarified, scanning and transmission electron microscopic studies were discussed.. Moreover, it discussed three virulence factors of E. histolytica trophozoite which enable it to penetrate the intestinal mucous membrane and the possibilities of presence other factors are not yet known. The epidemiology of amebae and its prevalence in Egypt and worldwide were discussed, however it was difficult to know the true prevalence of E. histolytica due to the similarity of its pathogenic strains and the non pathogenic E. dispar and E. moshkoviskii, and this was mainly because most researches depend on the microscopic examination of these parasites. On the other hand, the recent researches used the molecular biological methods which were only helpful to distinguish between these types.
Furthermore, the recent advances in the field of the immunological response of human body for E. histolytica infection was discussed as well as the discovery and description of the amoebic genome which was followed by a lot of trials to produce anti-amoebiasis vaccine, however this is still not an achievable target. This review discussed also the advances in the field of serological and immunological diagnosis of amoebic infection using PCR, isoenzymes and microarray techniques. The present work also discussed the
treatment of amoebic infections as well as the causes of resistance to
antiamoebic drugs.
Different types of free living amoebas, their ultrastructural morphology using electron microscopy, the methods of diagnosis, as well as diseases caused by them particularly in immunocompromized individuals, clinical picture of brain invasion which may be followed by severe complications and death.
Amoebic studies in Egypt were also an area of focus in the current review describing the different strains of amoebae which are found in Egypt, diagnosis and treatment. It was noticed that there is few researches in the field of differentiating E. histolytica, E. dispar and E. moshkoviskii. So we recommend more studies to be done on this point later on. In this study, we could not trace any work in the field of amoebiasis from all Upper Egyptian governorates, in spite of the abundance of the risk factors for amoebic
infection in most villages as well as some urbanized districts where sewage pollution of drinking water is not uncommon putting in mind that E.moshkovskii was essentially isolated from sewage contents. In such conditions, it is surprising that this parasite was not recorded from Egypt