Predictive factors for clinical response to allergy immunotherapy in children with asthma and rhinitis

To date, no predictive methods for the clinical response to allergy immunotherapy (AIT) are available. We sought to evaluate the pretreatment parameters used in diagnosing allergic asthma and/or rhinitis including allergen skin-prick test responses, serum specific and total IgE (sIgE and tIgE) levels and blood eosinophil counts, and to identify whether these can be used to predict clinical effectiveness in children treated with immunotherapy.

This study involved 185 children who had undergone 3 years of standardized-quality house-dust mite subcutaneous immunotherapy. Clinical characteristics and laboratory parameters were analyzed. A multivariate unconditional logistic regression model and receiver operating characteristic curves were used. Predicted probabilities and predictive areas under the curve were calculated.

The clinical response to AIT was effective in 129/185 (69.7%) patients. Four variables were associated with clinical response by multivariate logistic analysis: tobacco smoke exposure [odds ratio (OR) 2.845 and 95% confidence interval (CI) 1.147-7.058; p = 0.024], a family history of atopy (OR 2.881 and 95% CI 1.240-6.692; p = 0.014), a serum tIgE level ≥965 kU/l (OR 5.917 and 95% CI 2.320-15.089; p = 0.000) and an sIgE/tIgE ratio ≥6% (OR 0.336 and 95% CI 0.124-0.911; p = 0.032). The sensitivity and specificity of the area under the curve of the serum tIgE were higher than those of serum sIgE and sIgE/tIgE ratio alone.

Tobacco smoke exposure, atopic family history, serum tIgE and sIgE/tIgE ratio were in significant correlation with clinical response to AIT in children, which may be helpful for patient selection before immunotherapy. The serum tIgE is superior to both the serum sIgE/tIgE ratio and sIgE levels alone in predicting clinical effectiveness.