D2.70 - Contribution of Patch Testing with the Hairdresser-Specific Additional Series in the Etiological Identification of Contact Dermatitis in Hairdressers

Introduction:The hairdressing sector in Tunisia has experienced remarkable growth in recent years, driven by the introduction of numerous chemical processes and products, as well as new manicure and nail treatment techniques. These widely used products expose workers to irritant and allergic occupational dermatoses, often associated with wet work and inappropriate glove use.

Case reports:We report three cases of allergic contact dermatitis of the hands in hairdressers/beauticians. The first case involved a 21-year-old hairdresser presenting with bilateral erythematous, scaly, fissured lesions of the hands with fingertip pulpitis. She was exposed to acetone, hydrogen peroxide, and acrylic-based nail products. Patch testing with the European Standard Series (ESS) was positive for nickel. The hairdresser-specific series revealed additional positive reactions to ammonium persulfate, cobalt chloride hexahydrate, hydroquinone, decyl glucoside, and sodium metabisulfite.

The second case concerned a 28-year-old beautician with no history of atopy, who handled a concentrated keratin-based hair straightening product (“So Lyss”) and a pigmented acrylic gel (“Essentiel Beauty”) used in permanent nail polish. Patch testing with the hairdresser series and the handled products showed, in addition to nickel, a positive reaction to “Essentiel Beauty,” which contains methacrylate resin used in artificial nail application.

The third case involved a 30-year-old non-atopic beautician presenting with bilateral pruritic erythematous-vesicular keratotic lesions of the hands and fingers. She was exposed to nail gels and solvents. Patch testing with the hairdresser series and workplace products revealed a positive bullous reaction to a “gel primer” containing acrylates.

Conclusion:Allergic contact dermatitis remains common among hairdressers, and occupational allergens are continuously evolving. The use of additional hairdresser-specific allergen series, and in some cases patch testing with workplace products, is strongly recommended and highly relevant to identify causative agents not detected by the European Standard Series.These cases illustrate the increasing diversity and complexity of allergens present in hairdressing and beauty products. Acrylates, ammonium persulfate, methacrylate resins, and preservatives such as sodium metabisulfite have become frequent allergens, particularly in hair straightening products and semi-permanent nail polishes.