Serodiagnosis of Human Toxocariasis Using Adult Antigens of Toxocara canis

Introduction Toxocara canis has a worldwide distribution and is regarded as the main cause of human toxocariasis (1, 2). Infection in humans, particularly children, is frequently caused by accidental ingestion of embryonated Toxocara eggs present in soil, water, food, dirty hands, and vegetables or by ingestion of larvae in under-cooked giblets (3). The disease can be asymptomatic or can lead to death. The presentations of visceral larva migrans include fever, abdominal pain, malaise, weight loss, skin rash,hepatomegaly, hypergammaglobulinemia and respiratory symptoms/signs with eosinophilia (4).Toxocariasis has also been proposed as a potential etiology in neurologic disorders when the larvae migrate to the central nervous system (5, 6). In 1975, Savigny (7) described a technique for in vitro maintenance of T canis larvae with concomitant production of excretory/secretory (ES) or exoantigen (TEX). TEX was used in ELISA for testing patients with visceral toxocariasis. This assay showed a high degree of sensitivity and specificity (8, 9). Experiences during the past few years have shown several shortcomings in the use of adult somatic and adult excretory-secretory antigens of T. canis for diagnosis of toxocariasis. Therefore, the aim of the present study was to evaluate the efficacy of purified adult somatic and adult excretory – secretory antigens for diagnosis of human toxocariasis using ELISA and enzyme linked immunotransfer blot (EITB).