RESUMEN
Background: Allergic rhinitis [AR] is a common allergic disease. It has a marked effect on quality of life. Various populations of effector and regulatory T cells and their cytokines play a crucial role in allergic inflammation
Objectives: This study was designed to evaluate serum levels of IL-9 in subjects with allergic rhinitis and to investigate the association of its serum level with the severity of the disease, and its clinical parameters
Methodology: This study included 19 AR cases and 19 healthy controls. All patients and controls were subjected to the followings: full medical history, allergy skin test, nasal smear to detect eosinophilia, and measurement of serum levels of IL-9 by enzyme linked immune-sorbent assay [ELISA]. Cases were classified according to Allergic Rhinitis and its Impact on Asthma [ARIA] guidelines into mild, moderate and severe
Results: The median values of serum levels of IL-9 in AR cases were higher than in the controls [8.5 vs 6.85 pg/ml] with statistically significant difference [p =0.02]. Roc curve analysis, also showed significant association between the serum level of IL-9 in AR patients than controls [P value < 0.0001], the cut point was >7.5 pg/ml in AR patients with sensitivity and specificity of 77.78 and 83.33 % respectively. In addition, there was a significant association between the serum levels of IL-9 and degree of disease severity [P=0.01], and AR symptoms [nasal obstruction and irritative symptoms]. There was a significant association between sensitization to multiplicity of allergens and the mean level of IL-9 in AR cases [P< 0.05]
Conclusion: The elevated serum level of IL-9 in AR cases may provide new insight into the patho-physiology of the disease and into development of novel therapeutic targets