Contribution of the Leukocyte Adherence Inhibition Test to the Diagnosis of Non–IgE-mediated Immunoreactivity against Staphylococcus aureus in Patients with Intrinsic Atopic Dermatitis

Aims: The study aims to evaluate the potential of the Leukocyte Adherence Inhibition Test (LAIT) to discriminate non–IgE-mediated immunoreactivity against Staphylococcus aureus in patients with Intrinsic Atopic Dermatitis (IAD).

Study Design: We retrospectively examined the medical charts of 200 patients diagnosed with IAD who were investigated with an ex vivo challenge monitored by LAIT against an extract of S. aureus.

Place and Duration of Study: The study was conducted at Instituto Alergoimuno de Americana – São Paulo – Brazil – between January 2018 and October 2023.

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

Results: The LAI mean was 39.3%; SD 27.6%; ranging from 0% to 100%; mode = 0% (appeared 33 times). There was a wide range of distribution of LAI results, suggesting that some patients had immunoreactivity against the S. aureus allergens while others did not.

Conclusion: Our preliminary results support that the LAIT performed with S. aureus may differentiate diverse degrees of ex vivo immunoreactivity against their allergens in IAD patients.