IgE Abs to Der p 1 and Der p 2 as diagnostic markers of house dust mite allergy as defined by a bronchoprovocation test

BackgroundLimited information is available regarding the clinical usefulness of measuring the levels of IgE to allergen components from house dust mites (HDMs) in the diagnosis of genuine HDM allergy.MethodsTo evaluate the diagnostic usefulness of measuring levels of serum IgE antibodies (Abs) to allergen components from Dermatophagoides pteronyssinus (DP) as a predictor of immediate asthmatic response (IAR) to bronchoprovocation, we studied 55 DP-sensitized asthmatic patients who underwent a bronchoprovocation test using crude DP extract. The levels of IgE Abs to crude DP, nDer p 1, rDer p 2, and rDer p 10 in patients who showed IAR (n = 41) were compared with those in patients who showed no IAR (n = 14).ResultsWhile the frequencies of positivity for IgE Abs to nDer p 1 and rDer p 2 among the entire study population were 89 and 86%, respectively, all patients with IAR tested positive for both of them with high IgE concentrations. The areas under the receiver operating characteristic curves for IgE to nDer p 1 and rDer p 2 as predictors of IAR were 0.913 and 0.906, respectively. The specificity of IgE to nDer p 1 and rDer p 2 was higher than IgE to crude DP even at low cut-off points.ConclusionsIgE to nDer p 1 and/or rDer p 2 was highly predictive of allergen-induced IAR. These findings validate the clinical usefulness of measuring the levels of IgE to nDer p 1 and rDer p 2 as a diagnostic tool for genuine HDM allergy.