Relationship between Toxocara seropositivity and allergic rhinitis.

Background: Allergic rhinitis is the most common chronic disease in the upper respiratory tract, requiring better diagnostic methodology to counteract its onslaught. The purpose of this study was to investigate the association between Toxocara seropositivity and allergic rhinitis.

Methods: Sixty-four consecutive patients with allergic rhinitis and 61 healthy volunteers in the control group were included in this study. The diagnosis of allergic rhinitis was defined by positive epicutaneous prick test. The diagnosis of toxocariasis was established by IgG and specific IgE antibodies against Toxocara by ELISA method. All cases were examined for intestinal parasites also. The seropositive cases with Toxocara were reevaluated for symptoms and signs of toxocariasis.

Results: Higher toxocariasis seropositivity (ELISA IgG; 28.1%) rate was determined in the patients with allergic rhinitis and compared with the control groups (11.5%; p < 0.05). Specific IgE seropositivity (17.2%) was high for the patients with allergic rhinitis compared with the control group (3.3%; p < 0.05).

Conclusion: Our results show that there was a possible causal relationship between Toxocara infection and allergic rhinitis. Patients with allergic rhinitis from a region with high prevalence for this parasitic infection should be evaluated for Toxocara infection.