Nasal allergen-neutralizing antibodies correlate closely with tolerated intranasal allergen challenge dose following grass pollen subcutaneous immunotherapy in patients with local allergic rhinitis

Investigation of the diagnostic accuracy of basophil activation test for allergic phenotypes of rhinitis

INTRODUCTION

Basophil activation test (BAT) might be an alternative to nasal allergen challenge (NAC) to identify the allergic etiology in rhinitis patients. Here, we investigate the diagnostic performance of BAT for allergic phenotypes of rhinitis.

METHODS

Rhinitis patients and healthy controls were subjected to NAC with Dermatophagoides pteronyssinus (DP), Alternaria alternata (AA), grass (GP) and olive (OP) pollens. Rhinitis subjects also underwent skin prick test (SPT) with relevant allergens. Patients were classified into allergic rhinitis (AR, positive NAC and SPT), local allergic rhinitis (LAR, positive NAC and negative SPT), dual allergic rhinitis (DAR, defined as AR for ≥1 allergen and LAR for ≥1 allergen), and non-allergic rhinitis (NAR, negative NAC and SPT) phenotypes. BAT with DP, AA, GP and OP was conducted in study individuals and compared with NAC results.

RESULTS

A total of 47 AR, 31 DAR, 26 LAR, 12 NAR and 21 control subjects were recruited. The best positivity cut-offs of BAT for DP-, AA-, GP- and OP-driven allergy (all phenotypes) were a %CD63 cells of 8.650, 14.250, 26.200, and 12.780, respectively (AUC 0.851, 0.701, 0.887, and 0.921, respectively). Sensitivity, specificity, negative and positive predictive values of BAT (all phenotypes) ranged 43.5%(AA)-83.3%(OP), 88.9%(GP)-100%(AA), 87%(GP)-100%(AA), and 61.1%(DP)-80.0%(pollens), respectively. BAT identified 79%-100% of SPT-positive allergies (AR and DAR), and 25%-75% of SPT-negative allergies (LAR and DAR), while ≤10% of NAR/HC subjects tested positive. BAT positivity correlated with rhinitis severity in LAR patients (p = 0.018), and associated with conjunctivitis (p = 0.015) in allergic subjects.

CONCLUSION

BAT can replace NAC for AR confirmation, and limit the number of NAC required for LAR and DAR diagnosis. BAT can demonstrate sIgE in SPT-negative allergies.

Molecular allergy diagnosis enabling personalized medicine

Allergic patients are characterized by complex and patient-specific IgE sensitization profiles to various allergens, which are accompanied by different phenotypes of allergic disease. Molecular allergy diagnosis establishes the patient's IgE reactivity profile at a molecular allergen level and has moved allergology into the era of precision medicine. Molecular allergology started in the late 1980s with the isolation of the first allergen-encoding DNA sequences. Already in 2002, the first allergen microarrays were developed for the assessment of complex IgE sensitization patterns. Recombinant allergens are used for a precise definition of personal IgE reactivity profiles, identification of genuine IgE sensitization to allergen sources for refined prescription of allergen-specific immunotherapy and allergen avoidance diagnosis of co- versus cross-sensitization, epidemiologic studies, and prediction of symptoms, phenotypes, and development of allergic disease. For example, molecular IgE sensitization patterns associated with more severe respiratory allergies, severe food allergy, and allergy to honeybee or vespids are already established. The implementation of molecular allergy diagnosis into daily clinical practice requires continuous medical education and training doctors in molecular allergy diagnosis, and may be facilitated by clinical decision support systems such as diagnostic algorithms that may take advantage of artificial intelligence.

A novel dose-adjustment protocol for interrupted subcutaneous immunotherapy in children with allergic rhinitis

Aim: To assess the effectiveness and safety of a new protocol for adjusting doses during interrupted subcutaneous immunotherapy maintenance, exceeding an 8-week interval, with mite allergen injections in children with allergic rhinitis.Patients & methods: 194 children with allergic rhinitis who underwent subcutaneous immunotherapy and experienced interruptions lasting more than 8 weeks during maintenance were enrolled. Following the adoption of a novel dose-adjustment protocol, a real-world study was conducted.Results: After 3 years of subcutaneous immunotherapy, the novel group exhibited a significant reduction in allergy symptoms compared with baseline. Systemic reactions related to the novel protocol did not significantly increase.Conclusion: The novel protocol was deemed safe and effective, offering advantages of time savings and reduced burdens.