Andrew P. Word

Ear dermatitis + epoxy reactivity = hearing aid allergy?

Kaveh A. Nezafati, Ponciano D. Cruz Jr; Department of Dermatology, The University of Texas Southwestern Medical Center, Dallas, TX An unusually healthy 98-year-old woman presented with a 4-month history of an eczematous dermatitis that started on both ears and spread to the temples and forehead. Her only oral medication was ibuprofen and she was prescribed triamcinolone and clobetasol creams by dermatologists. Patch testing to 46 standard allergens and her 2 steroid creams showed a single positive to epoxy resin (1% w/w in petrolatum). This led us to focus on her hearing aids as a source of allergic contact dermatitis. Epoxy resins are an increasing cause of occupational contact dermatitis. Furthermore, given their favorable chemical and physical properties (excellent adhesiveness, high physical strength, and easy curing), they are used in a wide variety of commercial products like adhesives in clothing and elastics, coatings for technological devices and electrical wiring, roofing and flooring materials, and glues in artwork. Allergic dermatitis to epoxy can be due to components of the polymer (bisphenol A) and/or the curing agents and accelerants. Patch testing only to bisphenol A might not reveal the relevant allergen. We accessed Web-based postings for hearing aids and found epoxy resin in some devices. Repeated communication with the specific manufacturer of her hearing aid disclosed bisphenol A to be a monomeric component of epoxy resins in her device; however, the precise constituents are unknown to us. After consultation with the patient’s audiologist we sent the device back to the manufacturer for re-curing to reduce the amount of bisphenol A that may be potentially leaching from it. Once cured, we hope the device ceases to be a problem (or in the patient’s words, ‘‘no longer a terrible nuisance!’’).

Treatment of warts with contact allergens

Contact immunotherapy is an increasingly used, effective means of treating cutaneous viral warts. Dinitrochlorobenzene, diphencyprone, and squaric acid dibutylester are the most frequently used modalities, showing slight variances in adverse effect profiles and efficacy. All of these agents serve as safe treatment modalities when administered according to the guidelines recommended herein. We review the value of contact immunotherapy in the treatment of cutaneous viral warts.

Scalp "sensitivity" without visible lesions.

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