NEW YORK – One expert has characterized para-tertiary-butylphenol formaldehyde resin as a suitable candidate for the next pediatric contact allergen of the year, based on a growing number of case reports.
Para-tertiary-butylphenol (PTPB) formaldehyde resin is found in shin guards, push-up bras, and numerous other products used by children and adolescents.
Published case reports of contact allergies caused by PTPB formaldehyde resin date back several years, but use of this resin as an adhesive in a broad range of products – particularly leather goods, such as shoes, purses, and watch straps – appears to be increasing, according to Dr. Nanette B. Silverberg.
Dr. Silverberg presented a review of new trends in pediatric contact dermatitis at the American Academy of Dermatology summer meeting.
The causes of contact allergies in children evolve constantly because of the introduction of new products, and this should influence the order in which patch testing of specific allergens is performed, said Dr. Silverberg, a dermatologist at St. Luke’s–Roosevelt Hospital Center, New York.
In her update, she cited several recently designated "allergens of the year" from the American Contact Dermatitis Society (ACDS) and added some of her own.
Dr. Silverberg also emphasized tricks she has devised to increase the likelihood of a successful patch test, not least of which is enlisting parent cooperation. "It is important to convince parents that they are guilt free," she advised. In parents who begin to blame themselves for exposures, a sense of denial can interfere with efforts to cooperate with patch testing. To avoid this problem, she suggested a proactive effort to establish they are fault free. "Blame it on marketing if you must."
In light of the potential for lack of compliance, patch testing should be made as effortless as possible. For one approach, Dr. Silverberg suggested timing testing so it is not an excuse to miss school. Another tip was to use "heaps of tape and more tape" to keep the patch tests in place, and then provide patients with a roll of tape when they leave the office. She also recommended thinking in advance of strategies to reduce the risk of patch tests being inadvertently or intentionally removed by children, such as gauze wrap around the abdomen.
"The number one way to make patch tests work in young children is to keep your patch test panel streamlined and focused," Dr. Silverberg said. Particularly in young children, she suggested just one or two panels rather than three or four. While bribes such as lollipops and stickers "should be used judiciously," Dr. Silverberg said it is very helpful to outline each patch with highlighters that glow under Wood’s lamp to make results easier to assess.
Contact allergies are extremely common, and it is often possible to control the contact dermatitis before or even without confirming the allergen. For example, dialkyl thiourea, the ACDS allergen of the year in 2009, is another source of contact dermatitis to shin guards as well as other products, but reactions to this or PTPB formaldehyde resin can often be prevented simply by putting a layer of clothing in front of the skin. By the same principle, contact dermatitis from car seats is often caused by dimethyl fumerate, the ACDS allergen of the year in 2011, but can be prevented simply by laying fabric or creating some other barrier to prevent contact.
Methylisothiazolinone, a preservative and antifungal agent often found in moist towels and wipes, was recognized as the most recent (2013) ACDS allergen of the year. Dr. Silverberg noted that these wipes have surprisingly broad applications. While dermatitis on the hands and buttocks would be expected, she cautioned that patients use these to clean other skin surfaces, so a broad index of suspicion is needed.
The most common contact allergens, such as nickel, cobalt, and neomycin, remain relatively unchanged from year to year, but many of these products are used less frequently in children’s products in appreciation of the risks that they pose. The challenge is keeping abreast of evolving trends. While patch testing is an effective tool for identifying the source of a contact dermatitis to alert parents and patients of the products they should avoid, she said that technique is critical to patch test success.
Dr. Silverberg said she had no financial disclosures.