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Patch testing with benzoyl peroxide: reaction profile and interpretation of positive patch test reactions
Hans-Michael Ockenfels1, Wolfgang Uter, Holger Lessmann
1Department of Dermatology, Klinikum Hanau, 63450 Hanau, Germany. hautklinikum-hanau@ndh.net
Contact Dermatitis
|October 15, 2009
Summary
Benzoyl peroxide patch tests often yield reactions with unclear significance. Patients with atopic dermatitis are prone to irritant reactions, while dental technicians may experience true allergic responses.
Area of Science:
- Dermatology
- Allergology
- Contact Dermatitis
Background:
- Benzoyl peroxide (BP) 1% pet. patch testing frequently results in weak positive reactions of uncertain clinical relevance.
- Understanding BP reactions is crucial for accurate diagnosis in dermatology.
Purpose of the Study:
- To characterize the reaction patterns observed during benzoyl peroxide patch testing.
- To identify patient demographics and conditions associated with positive benzoyl peroxide patch test reactions.
Main Methods:
- Retrospective analysis of patch test data from the Information Network of Departments of Dermatology (IVDK).
- Data collected between 1992 and 2007, involving 29,758 patients tested with benzoyl peroxide 1% pet.
Main Results:
- Weak positive reactions (6.5%) and strong positive reactions (1.3%) were observed with benzoyl peroxide 1% pet.
- Strong positive reactions were linked to leg/face dermatitis, dental technician occupation, younger age, and female gender.
- Atopic dermatitis patients showed an increased risk of weak positive reactions only.
Conclusions:
- Benzoyl peroxide 1% pet. is a problematic patch test agent requiring careful interpretation of clinical relevance.
- Atopic dermatitis patients are susceptible to irritant reactions from benzoyl peroxide.
- True allergic reactions to benzoyl peroxide are rare, but may occur in specific occupational groups or with past leg ulcer treatments; acne treatments rarely cause sensitization.
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