Precision Medicine in House Dust Mite-Driven Allergic Asthma

Abstract

House dust mites (HDMs) are the allergenic sources most frequently involved in airway allergy. Nevertheless, not every sensitized patient develops respiratory symptoms upon exposure to HDM, and there is a clinical need to differentiate allergic asthmatics (AAs) from atopic non-allergic asthmatics with HDM sensitization. This differentiation sometimes requires in vivo provocations like the bronchial allergen challenge (BAC). Interestingly, recent data demonstrate that non-atopic patients with asthma can also develop positive BAC results. This novel phenotype has been termed local allergic asthma (LAA). The interest in identifying the allergic triggers of asthma resides in the possibility of administering allergen immunotherapy (AIT). AIT is a disease-modifying intervention, the clinical benefit of which persists after therapy discontinuation. Recently, new modalities of sublingual tablets of HDM immunotherapy registered as pharmaceutical products (HDM-SLIT tablets) have become commercially available. HDM-SLIT tablets have demonstrated a robust effect over critical asthma parameters (dose of inhaled corticosteroids, exacerbations, and safety), thus being recommended by international guidelines for patients with HDM-driven AA. In this review, we will summarize the current knowledge on the phenotype and endotype of HDM-driven AA, and LAA, address the difficulties for BAC implementation in the clinic, and discuss the effects of AIT in AA and LAA.

Organ‐specific allergen challenges in airway allergy: Current utilities and future directions

“…41 Moreover, the BAC would be required to identify bronchial allergen-specific reactivity in non-atopic asthmatics with a clinical history suggestive of allergy (local allergic asthma). 51 Conversely, direct (e.g., methacholine provocation) or other type of indirect (e.g., mannitol provocation) challenges are mostly used to detect bronchial hyperresponsiveness as an essential step in asthma diagnostic process. 52,53 Thus, the BAC and other bronchial challenges are complementary tests.…”

“…On the other hand, the NAC is needed to differentiate local allergic and non‐allergic rhinitis in non‐atopic individuals, and dual allergic rhinitis and mixed rhinitis in atopic subjects 41 . Moreover, the BAC would be required to identify bronchial allergen‐specific reactivity in non‐atopic asthmatics with a clinical history suggestive of allergy (local allergic asthma) 51 . Conversely, direct (e.g., methacholine provocation) or other type of indirect (e.g., mannitol provocation) challenges are mostly used to detect bronchial hyperresponsiveness as an essential step in asthma diagnostic process 52,53 .…”

Diagnostic Tools in Allergic Rhinitis

“…Of note, the IgE-dependent activation of basophils has been confirmed through BAT with wortmanin experiments (50,54). Moreover, BAT does not require a previous NAC to improve its sensitivity (52,54). Nevertheless, further studies are still required to confirm its diagnostic performance and to evaluate its cost-effectiveness (5, 52,54).…”

“…For them, BAT can be an essential tool because of its sensitivity for diagnosing IgE-mediated allergy (51). Of note, the IgE-dependent activation of basophils has been confirmed through BAT with wortmanin experiments (50,54). Moreover, BAT does not require a previous NAC to improve its sensitivity (52,54).…”

“…Moreover, BAT does not require a previous NAC to improve its sensitivity ( 52 , 54 ). Nevertheless, further studies are still required to confirm its diagnostic performance and to evaluate its cost-effectiveness ( 5 , 52 , 54 ).…”