Methods: A retrospective study evaluating patients between 5-65 years of age, of both sexes, with a clinical diagnosis of allergic rhinitis, was performed. The control group consisted of staff and students of the institution, aged 18-65 years, of both sexes, and no prior or current history of allergic rhinitis, asthma or atopic dermatitis. The measurement of specific IgE for Dp and Bt was performed using the ImmunoCAP and in the immediate hypersensitivity to Dp and Bt skin tests extracts from the FDA Allergenic were used.
Results: We evaluated 42 patients with allergic rhinitis and included 22 patients in the control group. We observed 90% sensitivity for Dp skin tests and 66.7% for measurement of specific IgE to Dp (p = 0.0001); 84% for Bt skin tests, and 61.9% for IgE specific for Bt (p = 0.0004). The specificity was 91% for Dp and Bt skin tests and 86% for specific Bt and Dp IgE (p> 0.05). The positive predictive value (PPV) was 95% for Dp skin tests, 94% for BT skin tests and 90% for serum specific IgE for both Dp and BT (p> 0.05). The negative predictive value (NPV) was 83% for Dp skin tests and 58% for the measurement of specific IgE for Dp (p = 0.0001); 77% for Bt skin tests and 54% for serum specific IgE for Bt (p = 0.001).
Conclusions: In the studied population, there was a higher sensitivity and better NPV of skin tests for Dp and Bt compared to the dosage of specific IgE. These results reinforce the usefulness of skin tests for immediate hypersensitivity to mites in clinical practice.