Background and objective: The prevalence of allergic contact dermatitis is high. Patch testing is the standard procedure to detect contact sensitivity. More than 3000 allergens are known, today. On the basis of the data of this study the top allergens are presented.
Patients and methods: The retrospective analysis is based on the patch test results collected by the Information Network of Departments of Dermatology in 2004. Data of 9948 patients (6175 female und 3773 male) referred for the evaluation of suspected contact allergy were analysed to determine the frequency of sensitization to the 10 most common contact allergens.
Results: The top ten allergens were nickel sulphate (frequency of sensitization standardized for sex and age 17.2 %), fragrance mix (7.2 %), balsam of Peru (6.7 %), cobalt chloride (6.5 %), potassium dichromate (5.3 %), colophony (4.6 %), lanolin alcohol (4.3 %), p-phenylenediamine (4.2 %), ammoniated mercury (3.5 %) und methyldibromoglutaronitrile/phenoxyethanol (3.4 %) in 2004.
Conclusions: Even after healing of the skin lesions of allergic contact dermatitis, it must be considered that sensitization persists indefinitely. Therefore, patients have to be informed exactly about their relevant contact allergens to ensure complete avoidance. To do so, physicians need a detailed knowledge of the most common contact allergens which are discussed in this paper.