Supplemental Patch Testing Identifies Allergens Missed by Standard Screening Series

Background: Supplemental patch testing is an adjunct to standard patch test screening series. Objective: To determine the demographics, characteristics, frequency, relevance, and interpretation of patch test reactions for supplemental patch testing. Methods: Retrospective study of patients tested 2017-2020 with North American Contact Dermatitis Group (NACDG) and supplemental screening series (Supplemental Series A [SSA], Supplemental Series B [SSB]). Demographics, characteristics, reaction strengths, relevance, and final interpretation were recorded. Results: Cohort included 791 patients; 73.5% female, 68.6% age >40 years. 74.1% were White, 15.2% Black, 5.7% Asian, and 1.5% Hispanic. The most common dermatitis sites were scattered/generalized (27.2%), face (24.0%), and hands (23.5%). For 2017-2018 and 2019-2020, respectively, 82% (318/388) and 78.4% (316/403) had ≥1 "allergic" reaction. In addition, 13.5% (52/385) and 11.7% (47/403) had SSA reactions, and 38.1% (115/302) and 31.5% (101/321) had SSB reactions. In the 87 (2017-2018) and 99 (2019-2020) patients with negative NACDG testing, 17 (19.5%) and 12 (12.1%) had supplemental reactions. Of the 34 supplemental allergens with reaction frequency ≥1%, 58.8% (20/34) are not part of the American Contact Dermatitis Society 90 (2020) or NACDG 2021-2022 screening series. The highest frequency allergens from this group were dodecyl and octyl gallate, cinnamic alcohol, phenyl salicylate, hexahydro-1,3,5-tris-(2-hydroxyethyl) triazine, and abitol. Conclusions: Supplemental patch testing identifies additional relevant allergens in patients with suspected allergic contact dermatitis.

Tinea versicolor in a premature infant

Tinea versicolor (TV) is a fungal skin infection that classically affects adolescents and young adults. Occasionally, it may be seen on the face of infants. We report an unusual case of widespread cutaneous TV in a premature infant.

Medical Adhesive Allergens: Retrospective Analysis of Cross-Sectional Data from the North American Contact Dermatitis Group, 2001-2018

BACKGROUND

Identification of allergens causing medical adhesive contact allergy is difficult.

OBJECTIVE

Characterize the demographics, clinical characteristics, patch test results and occupational data for North American Contact Dermatitis Group (NACDG) patients with medical adhesive contact allergy.

METHODS

Retrospective study of 43,722 NACDG patients patch-tested 2001-2018, with: 1) medical adhesive (tapes/band aids/adhesive aids/suture glue) source, 2) positive patch test, and 3) final primary diagnosis of allergic contact dermatitis.

RESULTS

313 (0.7%) patients met inclusion criteria. Compared to other patients with final primary diagnosis of allergic contact dermatitis, medical adhesive allergy patients were less likely male (odds ratio 0.58, 95% confidence interval [0.45-0.77]) and/or age >40 (0.76 [0.6-0.96]). The most common NACDG screening series allergens were colophony (80.7%), balsam of Peru (3.9%), 2-hydroxyethyl methacrylate (2.7%) and carba mix (2.7%). One-fourth (79/313, 25.2%) had positive patch test reactions to supplemental allergens/materials, and 17.3% (54/313) only had reactions to supplemental allergens/materials.

LIMITATIONS

Results of comprehensive patch testing may be prone to referral population selection bias and may not be representative of the general dermatology population.

CONCLUSION

Colophony was the most common allergen. Supplemental allergens and materials should be tested in the evaluation of suspected medical adhesive contact allergy.

Tattoo hypersensitivity reactions: inky business

Hypersensitivity reactions can occur in both temporary and permanent tattoos. Traditional temporary tattoos consist of red henna or black henna; paraphenylenediamine is the most common allergen and usually is present in black henna. Contact allergy to genipin in jagua temporary tattoos also has been reported. Permanent tattoo inks traditionally contain black pigment of amorphous carbon or black iron oxides or metals. Modern permanent tattoo ink is a blend of pigments, including metals, as well as carbon, azo, diketopyrrolopyrrole, quinacridone, anthraquinone, dioxazine (purple), or quinophthalone (yellow) dyes. Patch testing for temporary and permanent tattoos is complex and challenging.