Prevalence study of Entamoeba histolytica/ dispar by microscopic and serological diagnosis (ELISA) using species verification by nested PCR in North Iraq region

Amebiasis is one of the important diseases caused by Entamoeba histolytica, a protozoan parasite, affecting the human intestinal mucosa and other organs. The aim of this study was to determine the prevalence of E. histolytica and Entamoeba dispar in patients hospitalized in Duhok, Erbil and Sulaymaniyah by microscopy (by native-Lugol, trichrome staining), ELISA and Nested-PCR methods. It was examined stool samples from 162 hospitalized persons in this study. Firstly, the samples were examined under light microscopy using native-Lugol and trichrome staining methods. In the study, ELISA and PCR methods were used to distinguish E. histolytica and E. dispar from each other. Entamoeba spp. were detected in 58 (35.8%) of the 162 stool samples examined. Entamoeba spp. were found in 22 (33.8%), 17 (34%) and 19 (40.4%) persons in Duhok, Erbil and Süleymaniye cities, respectively. In the second stage, all stool samples were examined by ELISA, and E. histolytica was detected in eight (4.9%) of the stool samples. E. histolytica was determined in 4 of 65 persons (6.1%) in Duhok city, 2 of 50 persons (4%) in Erbil city, and 2 of 47 persons (4.2%) in Sulaimaniyah city. Then, all stool specimens were examined by Nested PCR, and E. histolytica in nine of the samples (5.5%), E. dispar in 37 (22.8%) and mixed infection in three (1,8%) (E. histolytica and E. dispar together) were detected. In Duhok City, E. histolyca was found in five patients (7.6%), E. dispar in 14 patients (21.5%), and mix infection (E. histolyca and E. dispar) in two patients (3%) by PCR. In Erbil City, E. histolica was found in two patients (4%), E. dispar in 10 patients (20%), and mix infection (E. histolyca and E. dispar) in one patient (2%) by PCR. In Sulaimaniyah City, E. histolyca was found in two patients (4.2%), and E. dispar in 13 patients (27.6%) by PCR. In this study, it was found that the PCR method is much more sensitive than the other diagnostic methods in the detection and differentiation of E. histolytica and E. dispar, and it is also a very useful and easy method of ELISA for the detection of E. histolytica in stool