Evaluation of a developed IMB based-ELISA in diagnosis of urinary schistosomiasis in areas at risk in Upper Egypt

Abstract

Background: Nanotechnology enables researchers to boost accuracy of the existing diagnostic techniques. Immunomagnetic beads (IMB) based-ELISA was utilized to diagnose several parasitic diseases; schistosomiasis mansoni and japonicum, toxoplasmosis and neurocysticercosis. Objectives: The present work aims to develop and evaluate a novel nano-diagnostic assay using gold nanoparticles (AuNPs) in ELISA (IMB based-ELISA) for the diagnosis of urinary schistosomiasis. Subjects and Methods: IMB based-ELISA assay was developed by preparation of polycolonal antibodies (pAbs) against Schistosoma soluble egg antigen (SEA). The developed novel assay was evaluated in urine samples of 290 schoolchildren collected from primary and preparatory schools in four villages in Beni-Suef governorate, Egypt. Urine samples were screened by chemical reagent strips (Combi 10) and examined by urine microscopy (UM). The conventional ELISA technique was used to evaluate the efficacy of IMB based-ELISA using UM as the gold standard method for diagnosis of urinary schistosomiasis. Results: The novel IMB based-ELISA assay succeeded to diagnose 50 out of 290 schoolchildren (17.2%). In comparison with other methods, results showed that 39/290 (13.4%) were positive by UM and 53/290 (18.3%) by conventional ELISA. A sensitivity, specificity and diagnostic accuracy of the evaluated ELISA assay using UM as the gold standard method were 94.87%, 95.22% and 94.48% respectively. It was observed that Combi-10 gave sensitivity and specificity of 35.9% and 94.9% respectively for micro-haematuria and proteinuria. Conclusion: IMB-ELISA based on AuNPs provides a more rapid as well as sensitive detection of SEA in urine samples of patients with active schistosomiasis. Its high sensitivity and specificity ensure its application in field studies. Additionally, urinary schistosomiasis proved highly prevalent in schoolchildren living in Beni-Suef villages.