The study of a possible correlation between serum levels of interleukin 17 and clinical severity in patients with allergic rhinitis.

Introduction: Allergic rhinitis (AR) is one of the most common allergic diseases, which affects ∼20% of the world's population. T-helper (Th) type 2 cells produce interleukin (IL) 4 and IL-13, and mediate allergic responses, and these cytokines have been extensively studied as key players in the atopic airway diseases. However, the involvement of Th17 cells and IL-17 in AR has not been clearly examined.

Aim: To reevaluate AR clinical severity with serum IL-17, whether IL-17 affects the disease alone or in contribution with the atopic predisposition.

Patients and methods: During an 18-month period, 39 individuals were divided into three groups: A, (13 control), B (13 with mild-to-moderate AR), and C (13 with severe AR). Both group B and group C patients (26) were subjected to clinical examination and allergy skin testing, and to measurement of both total serum immunoglobulin E (IgE) and IL-17 levels. Eleven patients with AR then were exposed to 6 months of cluster immunotherapy, whereas the rest of the patients were not exposed.

Results: Revealed a significant elevation of serum IL-17 levels with an associated increase in serum IgE in the patients with AR compared with controls and revealed that the serum levels of both total serum IgE and IL-17 decreased significantly after cluster immunotherapy.

Conclusion: These preliminary results added new data about the use of injective immunotherapy as well as reported on the use of sublingual immunotherapy.