Background and Aim: Toxocariasis is a common parasitic zoonosis of humans, dogs and cats. Migration of Toxocara larva in the internal organs is accompanied by a variety of complications such as hepatomegaly, marked eosinophilia, pulmonary and ocular symptoms. In some cases, symptoms are nonspecific and the patients may only show allergy-like cutaneous and pulmonary manifestations. Considering the significant increase in the prevalence of allergic disorders, study of the possible etiologies of these disorders can lead to the early diagnosis and effective treatment of the disease. In this study prevalence of anti-toxocara antibody and some hematological parameters were compared between allergic and non-allergic children.

Materials and Methods:  Our experimental group included 200 children under 15 years of age with skin and/or respiratory allergies referring to allergy clinics, and our control group consisted of 238 non-allergic children, matched to the experimental group in regard to age and sex. Specific anti-toxocara IgG titers were measured by TES/Ag-ELISA technique. Eosinophilia and leukocytosis were extracted from the CBC results.  We used T-test and chi-square to compare the results between the two groups.

Results: The prevalence of anti-toxocara IgG in the children with allergic manifestations was significantly higher (4.5%) than that in the healthy children (0.8%). Children with allergic manifestations had a higher rate of eosinophilia (16.5%) compared to healthy children (0.4%), but there was no significant correlation between eosinophilia and toxocariasis serology.

Conclusions: Regarding the higher prevalence of anti-toxocara antibodies in the children with skin and respiratory allergies, investigation of toxocariasis in the patients with allergic symptoms is recommended.

Keywords: Toxocariasis, Serology, Allergy, TES/Ag-ELISA.

Received: Aug 17, 2016      Accepted: Jan 23, 2017