Contributions of the Leukocyte Adherence Inhibition Test to the Diagnosis of Hypersensitivity Reactions Produced by Nickel

Aims: To evaluate the potential of the Leukocyte Adherence Inhibition Test (LAIT) as a diagnostic tool for nickel sensitization in patients with clinical suspicion of Nickel Hypersensitivity (NiH).

Study Design: We retrospectively examined the medical charts of a population of 102 patients diagnosed with chronic extensive dermatitis that prevented the employ of the diagnostic Patch Test and were investigated through an ex vivo challenge monitored by LAIT against NiSO4 (H2O)6.

Place and Duration of Study: Instituto Alergoimuno de Americana – São Paulo – Brazil – between January 2018 and May 2023.

Methodology: Two groups were separated according to the patient’s perception of pruritic reactions after prolonged contact with nickel alloys. Group A was composed of 45 patients denying pruritic reactions to prolonged contact with nickel alloys. Group B was composed of 57 patients that complained of local pruritic reactions produced by prolonged contact with nickel alloys. Cascade distribution charts were mounted with the range groups of Leukocyte Adherence Inhibition (LAI) results for visual comparison between the groups. The difference between the LAI means was studied with the help of the nonparametric Mann-Whitney U Test.

Results: The Cascade distribution charts showed a distinct distribution of LAI when comparing the two groups. This significative difference was supported by the Mann-Whitney U Test under p < 0.01.

Conclusion: Our preliminary results support the fact that the LAIT performed with NiSO4 (H2O)6 has the potential to become a diagnostic tool to help physicians to diagnose patients with NiH.