Differential Detection of Entamoeba histolytica and Entamoeba dispar Using PCR-Based Assay

E. histolytica is endemic in large parts of the world and is responsible for up to 100.000 deaths per year. However, the recent identification of E. dispar as nonpathogenic species which is morphologically indistinguishable from E. histolytica and does not require treatment has indicated the need of alternative methods for detection which are able to differentiate between the two organisms In this study we evaluated the utility of conventional PCR as a method for the detection and differentiation of E. histolytica from E. dispar.The present study was carried out on 60 from outpatient clinics of Zagazig University Hospital 40 diagnosed microscopically as E. histolytica/dispar infected persons. And 10 cases proved microscopically to be infected with parasitic infections other than E. histolytica E. dispar and 10 clinically and microscopically negative subjects as a control negative group. results were obtained:1- In symptomatic patient E. histolytica is more prevalent than E. dispar (50%) (35%) respectively.2- In asymptomatic subjects E. dispar is more prevalent than E. histolytica.3- Direct wet mount show the lowest sensitivity(22.5%) followed by iodine stained smears (52.2%) in relation to formol ether concentration technique and (22%) and (51.2%) respectively in relation to PCR technique while sensitivity of formol ether concentration technique recorded 97.6% in relation to PCR technique .4- PCR technique show high sensitivity and specificity (100%) and (95%) respectively in relation to formol ether concentration technique.5- Amoebic infection was more prevalent among age group between 10-19 years (37%).6- Amoebic infection was more common among females (61%) than males (39%).7- Amoebic infection was more prevalent in rural areas (74%) than those from urban areas (56%).