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Patch Testing to Paraphenylenediamine: The North American Contact Dermatitis Group Experience (1994-2018)
Erin M Warshaw1,2,3, Malina Yamashita Peterson1,4, Amber R Atwater5
1From the Department of Dermatology, Park Nicollet/Health Partners Health Services, Minneapolis, Minnesota, USA.
Dermatitis : Contact, Atopic, Occupational, Drug
|July 31, 2023
Summary
Paraphenylenediamine (PPD) allergy affects 5.6% of patients, particularly women over 40. Hair dye is the most common cause of PPD allergic contact dermatitis, often leading to relevant reactions.
Area of Science:
- Dermatology
- Epidemiology
- Allergology
Background:
- Paraphenylenediamine (PPD) is a common allergen in dyes, frequently causing allergic contact dermatitis.
- Understanding the epidemiology of PPD allergy is crucial for prevention and management strategies.
Purpose of the Study:
- To analyze the epidemiological characteristics of allergic patch test reactions to PPD.
- To identify demographic factors, exposure sources, and co-reactivity patterns in PPD-allergic individuals.
Main Methods:
- Retrospective analysis of North American Contact Dermatitis Group data (1994-2018).
- Inclusion of 54,917 patients tested for PPD (1% petrolatum).
- Comparison of demographics, dermatitis sites, reaction strength, clinical relevance, occupational links, and co-reactivity between PPD-allergic and PPD-negative groups.
Main Results:
- 5.6% of patients exhibited allergic reactions to PPD.
- PPD allergy was associated with female gender and age over 40.
- Hair dye was the primary source (73.5%), followed by apparel (3.9%).
- Common co-reactants included benzocaine and disperse dye mix.
Conclusions:
- The prevalence of PPD allergy remained stable at 5.6% over 24 years.
- PPD allergy is linked to specific demographics and exposure, notably hair dye use.
- Allergic reactions are often clinically relevant, emphasizing the need for awareness and avoidance.
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