Basophil Activation Test useful Alternative to Nasal Allergen Challenge Test for Allergic Rhinitis, suggests study

A recent groundbreaking study
confirmed that the basophil activation test (BAT) is a useful tool instead of
nasal allergen challenges to confirm allergies as per results published in the
journal Allergy.

Allergic rhinitis (AR) is an inflammatory
condition of the nasal mucosa associated with increased morbidity and reduced
quality of life. Skin prick test (SPT) and serum allergen-specific (sIgE) are
some of the tests for AR after a thorough clinical examination. nasal allergen
challenge (NAC) is advised to individuals whose clinical history is not
sufficiently clarifying regarding the relevance of the sensitizations detected.
Some individuals have negative SPT tests but positive NAC which is called local
allergic rhinitis (LAR). Some may have a combination of allergies with and
without SPT positivity called dual allergic rhinitis (DAR). Research shows that
BAT can be used as a standard test for AR. Research shows that BAT can be an alternative
to NAC for allergic patients with an IgE-dependent endotype. Hence, researchers
conducted a study to investigate the diagnostic performance of BAT for allergic
phenotypes of rhinitis.

Also Read: Air pollution linked to peanut allergy during childhood, unravels study

A prospective study included patients
≥18 years with chronic rhinitis for ≥2 years. They were subjected to NAC with
the allergens from Dermatophagoides pteronyssinus (DP), Alternaria
alternata (AA), Grass pollen (GP), and Olea europaea pollen (OP). Rhinitis
subjects underwent a 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, de-fined as AR for ≥1 allergen and LAR for ≥1 allergen), and non-allergic
rhinitis (NAR, negative NAC and SPT) phenotypes. BAT was used to measure allergic
reactions in various samples. Shapiro-Wilk tests were used to assess data
normality, ROC curves were used to assess the diagnostic accuracy of BAT.

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 from 43.5%(AA)-83.3%(OP),
    88.9%(GP)-100%(AA), 87%(GP)-100%(AA), and61.1%(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 was associated with conjunctivitis (p = 0.015)
    in allergic subjects.
Also Read: Long-Term Biologic Treatment tied to Clinical Remission in Nearly Half of Severe Asthma Patients: 7Study Reveals

Thus, the study concluded that
BAT can be effectively used for various rhinitis phenotypes. This comes after
BAT positivity was linked to severe rhinitis in LAR and conjunctivitis in
allergic individuals. As BAT can widely discriminate between allergic and
non-allergic rhinitis with high sensitivity and specificity this can be used for
early diagnosis and a tailored treatment plan.

Further reading: Testera-Montes
A, Ariza A, Sola-Martinez RA, et al. Investigation of the diagnostic accuracy
of basophil activation test for allergic phenotypes of rhinitis. Allergy.
Published online November 5, 2024. doi:10.1111/all.16390

Facebook Comments