Acrylate Patch Testing for Allergic Contact Dermatitis Over 28 Years: Hierarchical Clustering for Subgroup Analysis and Computational Optimization for Patch Test Selection.

BACKGROUND: Acrylate allergy is rising, with many patients showing patch test positivity to multiple acrylates. Understanding acrylate sensitivity can guide avoidance and optimize screening. OBJECTIVES: To quantify acrylate patch test positivity, define subgroups using hierarchical clustering, and algorithmically optimize acrylate patch testing series. METHODS: We conducted a retrospective review of 27 acrylate allergens patch tested at 3 Mayo Clinic sites (Arizona, Florida, Minnesota) from 1997 to 2024; 14 had ≥1% positivity. Pairwise copositivity rates were background-corrected and analyzed using hierarchical clustering, followed by computational optimization for patch test screening. RESULTS: Among 17,148 patients, 90,818 tests yielded 1,557 positives (1.71%). Most frequent positive reactions were 2-hydroxyethyl acrylate 0.1% (HEA, 5.4%), 2-hydroxypropyl methacrylate 2% (HPMA, 5.0%), and 2-hydroxyethyl methacrylate 2% (HEMA, 4.6%). Clustering revealed 2 general subgroups, with ethyl cyanoacrylate 10% (ECA) showing minimal copositivity to other acrylates. Optimization analysis for screening showed that one allergen (HEMA) captured 49.4% of sensitized patients; 2 (HEMA + ECA) captured 72.2%. Four allergens, including HEMA, ECA, HEA, and diethylene glycol diacrylate 0.1% (DEGDA), captured >90%, and a 7-allergen series captured 100%, with no higher yield from additional acrylates in standard screening. CONCLUSIONS: Acrylate allergy is heterogeneous, comprising 2 subgroups, with cyanoacrylates co-reacting separately. Algorithm-guided series refinement improves diagnostic efficiency by prioritizing high-yield allergens for screening while minimizing unnecessary testing.