EJMS

Abstract

Amoebiasis is a worldwide disease caused by the protozoan parasite Entamoeba histolytica which can be found worldwide but it's more prevalent in tropical and subtropical regions. The present study aims to compare between direct stool examination methods and copro-antigen detection by ELISA in the diagnosis of amoebic dysentery. The present study was carried out on 60 stool samples of patients aged from 6 up to 56 years (34 males and 26 females) complaining of different gastrointestinal troubles chosen from Pediatric and Tropical Medicine Outpatient Clinics of Zagazig University Hospitals and 12 normal healthy cases were considered as a negative control group. The stool samples were examined microscopically for detection of E. histolytica cysts or trophozoites and by ELISA for detection of E. histolytica copro-antigen. Microscopic examination revealed Entamoeba infection in 28 cases (46.6%), 13 of them (21.6%) was E.histolytica/E.dispar infection, while 15 (25%) were mixed with other parasitic infections; parasites other than Entamoeba were detected in 20 cases (33.3%). ELISA detected 25 of 28 E.histolytica positive cases and detected 0 of 20 cases infected with parasites other than Entamoeba. This means that no cross reactivity can occur with copro-antigen detection system when parasites other than E. histolytica or other spp of Entameoba (E.dispar) are found in stool. ELISA technique for detection of copro-antigen is more reliable for specific detection of E. histolytica infection than stool analysis as there is no cross-reactivity with other types of non-pathogenic Entameoba which cannot be differentiated by microscopic examination as E.dispar.