Toxocariasis; A Neglected Tropical Disease, Association With Asthma, Chronic Urticaria and Unexplained Neurologic Manifestations Among Children

Abstract

Background: The link between parasitic infections and either allergic diseases or unexplained neurologic manifestations was hypothesized especially in children. However, the debate continues regarding this link. Aim of the work: To determine the seroprevalence of toxocariasis in children with different allergic diseases [bronchial asthma and skin allergy], besides the unexplained neurological manifestations [epilepsy and focal neurologic deficits] in children. Patients and methods: Children with bronchial asthma [40 children], skin allergy [40 children], and unexplained neurological manifestations [epilepsy and focal neurologic deficits], [40 children] were included. All underwent a full history taking, clinical examination, lab investigations and determination of seropositivity for Toxocara canis. Results: Eosinophilia was reported in 22.5%, 30.0% and 17.5% of asthma, skin and unexplained neurological manifestations groups respectively. In patients with asthma, the prevalence of toxocariasis was 15.0%, in skin disease, the incidence was 7.5% and in unexplained neurological manifestations, it was 12.5%. There was no significant difference between positive and negative toxocariasis in regard to patient demographics. But there was a significant increase in contact with pets, chronic urticaria, lymph nodes involvement and eosinophilia in positive when compared to negative groups. Conclusion: The association between Toxocara canis infection and allergic diseases such as bronchial asthma, chronic urticaria and unexplained neurological manifestations [epilepsy and focal neurologic deficits], was confirmed in the present work. The contact with dogs and cats [pets] was the major determinant risk factor explaining such association. Prospective cohort studies were warranted to examine the cause effect relationship.