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North American Contact Dermatitis Group Patch Test Results: 2019-2020.
Joel G DeKoven1,2, Erin M Warshaw3,4,5, Margo J Reeder6
1From the *Division of Dermatology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada.
Dermatitis : Contact, Atopic, Occupational, Drug
|March 14, 2023
Summary
Patch testing identified common allergens causing allergic contact dermatitis (ACD). Methylisothiazolinone (MI) allergy prevalence may be stabilizing in North America, but other allergens like nickel and fragrance mix I remain prevalent.
Area of Science:
- Dermatology
- Allergology
- Epidemiology
Background:
- Allergic contact dermatitis (ACD) is a common skin condition.
- Patch testing is crucial for diagnosing ACD.
- The North American Contact Dermatitis Group (NACDG) monitors allergen prevalence.
Purpose of the Study:
- To report NACDG patch testing results from 2019-2020.
- To identify prevalent allergens and trends in ACD.
- To assess changes in allergen positivity compared to previous periods.
Main Methods:
- Standardized patch testing with 80 screening allergens and supplemental allergens.
- Data collected from 4121 patients across 13 North American centers.
- Analysis of positive reactions and primary ACD diagnoses.
Main Results:
- Nickel (18.2%), methylisothiazolinone (MI) (13.8%), and fragrance mix (FM) I (12.8%) were most common positive allergens.
- Prevalence increased for FM I, hydroperoxides of linalool (HPL), benzisothiazolinone (BIT), propolis, and hydroperoxides of limonene.
- MI positivity did not increase, suggesting a potential plateau in the MI allergy epidemic.
Conclusions:
- Patch testing remains essential for diagnosing ACD.
- While MI allergy may be stabilizing, other allergens continue to be significant.
- A substantial number of patients react to allergens not included in standard series, highlighting the need for comprehensive testing.
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