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North American Contact Dermatitis Group Patch Test Results 2013-2014
Joel G DeKoven1, Erin M Warshaw, Donald V Belsito
1From the *Division of Dermatology, Department of Medicine, University of Toronto, Canada; †Department of Dermatology, University of Minnesota; ‡Minneapolis VAMC, Minnesota; §Columbia University Medical Center, New York, NY; ∥Department of Medicine, Division of Dermatology, McGill University Health Centre, Montreal, Canada; ¶University of California, San Francisco; #Department of Dermatology, Cleveland Clinic Lerner College of Medicine, Ohio; **Department of Dermatology, Pennsylvania State University, Hershey; ††DS Research, Louisville, KY; ‡‡Division of Dermatology, Group Health Associates, Cincinnati, Ohio; §§Department of Dermatology, Keck School of Medicine, University of Southern California, Los Angeles; ∥∥Department of Medicine, Division of Dermatology, University of Ottawa, Canada; ¶¶The Ohio State University, Columbus; ##Section of Dermatology, Dartmouth Medical Center, Lebanon, NH.
The North American Contact Dermatitis Group (NACDG) found increasing sensitivity to methylisothiazolinone and other allergens. Expanded patch testing is crucial for diagnosing allergic contact dermatitis.
Area of Science:
- Dermatology
- Allergology
- Epidemiology
Background:
- Patch testing is the primary diagnostic method for allergic contact dermatitis.
- The North American Contact Dermatitis Group (NACDG) collects and analyzes patch testing data.
Purpose of the Study:
- To document NACDG patch testing results from 2013-2014.
- To analyze trends in allergic contact dermatitis and identify prevalent allergens.
Main Methods:
- Standardized patch testing with 70 allergens across 13 North American centers.
- Data verification, central database entry, and statistical analysis using chi-squared test.
Main Results:
- 4871 patients tested; 49.5% diagnosed with allergic contact dermatitis.
- Increased positive reaction rates for methylchloroisothiazolinone/methylisothiazolinone and hydroxyethyl methacrylate.
- Methylisothiazolinone showed a high positive reaction rate (10.9%); other new allergens also showed significant reactions.
Conclusions:
- Confirms an epidemic of methylisothiazolinone sensitivity in North America.
- Highlights the need for patch testing beyond standard screening series for comprehensive diagnosis.
