How Many Patients Undergoing Patch Tests React to Supplemental Allergen?
About 20 percent of patients who underwent patch testing had relevant reaction
By Dermsquared Editorial Team | November 03, 2021
About one in five patients who undergo patch testing to an allergen screening series of 65 to 70 allergens have a relevant reaction to supplemental allergens/substances, according to a study published online Nov. 3 in JAMA Dermatology.
Erin M. Warshaw, M.D., from Park Nicollet Health Services in Minneapolis, and colleagues conducted a 17-year cross-sectional analysis of North American Contact Dermatitis Group (NACDG) data from multiple centers. A total of 43,417 patients with dermatitis underwent patch testing with the NACDG screening series of 65 to 70 allergens and supplemental allergens as clinically indicated.
The researchers found that 21.9 percent of those who underwent patch testing to the screening series had currently relevant reactions to one or more supplemental allergens or substances. Patients with supplement-positive findings were significantly less likely to be men and/or have atopic dermatitis (odds ratios, 0.90 and 0.89, respectively). Among those with supplement-positive findings, the common primary sites of dermatitis included the face, hands, and scattered/generalized distribution (30.1, 21.4, and 17.3 percent, respectively). Personal care products and clothing/wearing apparel were frequent sources of supplemental allergens (51.4 and 18.1 percent, respectively). Supplemental allergens were occupationally related in 16.9 percent, including precision production, craft, or repair workers (25.1 percent). Overall, 25.7 percent of those with supplement-positive findings had no currently relevant reactions to NACDG screening allergens.
"These results suggest that comprehensive patch testing would be useful for the diagnosis and management of contact allergy," the authors write.
Several authors disclosed financial ties to the pharmaceutical industry.