Contribution of the Leukocyte Adherence Inhibition Test in Diagnosing Non–IgE-Mediated Immunoreactivity against Aspergillus fumigatus in Patients with Allergic Rhinitis and Asthma

Aims: To evaluate the potential of the Leukocyte Adherence Inhibition Test (LAIT) to discriminate non–IgE-mediated immunoreactivity against Aspergillus fumigatus in patients with non–IgE-mediated Allergic Rhinitis and/or Asthma.

Study Design: We retrospectively examined the medical charts of 100 patients diagnosed with respiratory allergy with clinical suspicion of non–IgE-mediated fungal hypersensitivity who were investigated with an ex vivo challenge monitored by LAIT against an extract of A. fumigatus.

Place and Duration of Study: Instituto Alergoimuno de Americana – São Paulo – Brazil – between January 2018 and January 2024.

Methodology: The percentage of Leukocyte Adherence Inhibition (LAI) promoted by the ex vivo challenges with A. fumigatus extract was distributed in ranges through a cascade distribution chart to outline the variability of the results.

Results: The LAI ranged from 0% to 90%; the mean was 52%; the median was 55.5%; the standard deviation was 21%; the Mode was 61% (appeared six times), showing a Gaussian Distribution. This extensive distribution of LAI results suggests that some patients had non–IgE-mediated immunoreactivity against A. fumigatus allergens while others did not.

Conclusion: Our preliminary results support that the LAIT performed with A. fumigatus may discriminate diverse degrees of ex vivo immunoreactivity against this airborne allergen in patients suffering from respiratory allergies.