Patterns provide clues to causes of facial allergic contact dermatitis
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Key takeaways:
- Fragrance mix one, balsam of Peru, botanicals and nickel are common causes.
- Patterns along the lateral sides of the face may be due to shampoos and conditioners as they rinse off the scalp.
SAN ANTONIO — Different patterns of allergic contact dermatitis on the head and face may provide clues about what caused these outbreaks, Heather O’Connell, PA-C, said at the 16th Annual Allergy, Asthma & Immunology CME Conference.
“A conservative estimate is that one in three of our patients with atopic dermatitis have allergic contact derm,” O’Connell, who is the incoming president of the Association of PAs in Allergy, Asthma and Immunology, said during her presentation.
The prevalence of allergic contact dermatitis among patients with AD increases when the duration of eczema is longer, when they have difficulty in treating eczema or when they have facial eczema, she continued.
Also, O’Connell noted that allergic contact dermatitis usually happens 2 to 5 days after exposure to the allergen. Prior exposure is necessary for a reaction to occur, she added, and it usually is not dose dependent.
“Even a small amount of the allergen can produce the dermatitis,” she said.
Allergic contact dermatitis may spread from the site where the allergen is applied to the skin to elsewhere as well, O’Connell said. Additionally, pruritis is the dominant symptom, followed by burning and stinging.
The scalp
“Interestingly enough, the scalp is an uncommon site for allergic contact dermatitis,” O’Connell said, attributing this to its thicker skin, high sebaceous unit count and lack of folds and wrinkles.
“All of those things actually make it a really good barrier,” she said, noting that it is more likely for an allergen applied to the scalp to affect surrounding areas such as the face, eyelids and neck.
As the allergen is rinsed off, it may cause a pattern running down the sides of the face. There also may be a hairline pattern on the upper border of the forehead and above the ears. Geographic patterns may emerge only where the allergen directly contacts the skin as well, typically in the occipital or posterior auricular regions.
Fragrance mix one, which is a category of fragrances found in cosmetics and personal care products based on cross-reactivity, is the most common allergen affecting the scalp and neck.
The next most common allergen affecting the scalp and neck is balsam of Peru, which is used in food flavorings and personal care products, followed by botanicals, quaternium-15, cocamidopropyl betain (CAPB), acrylates, paraphenylendiamine (PPD) and glycerl thioglycolate.
“When I’m talking about botanicals, I’m talking about oils that are derived from plants,” O’Connell said. “Then they’re mixed with alcohol and distilled waters to make perfume.”
Quaternium-15 is a formaldehyde-releasing preservative. CAPB is a sudsing agent used in shampoos and conditioners. Acrylates, used to plasticize or harden products, often are found in acrylic nails and other cosmetics. PPD is a hair dye and the most common hair dye allergen.
“The darker your patient’s hair dye is, the more PPD it has in it,” O’Connell said. “It’s also used in textile dyes and in temporary tattoos.”
is used in perms.
“If you have a patient who still gets perms, that’s the main allergen,” O’Connell said.
The face
Allergic contact dermatitis often affects the face, O’Connell said, and it affects women more often than men.
“That’s probably not surprising to most of us,” she said.
O’Connell noted research indicating that approximately 26.2% of patients referred for patch testing had facial dermatitis, and 30% of those cases were caused by a cosmetic.
Although facial dermatitis can be caused by direct exposure, she continued, it also could be caused by indirect transfer.
Further, O’Connell said that the average consumer applies more than 30 pounds of personal care products to themselves each year. Women use an average of about 12 personal care products with about 168 unique chemicals each day, and men use an average of about six products with about 85 unique chemicals.
Fragrance mix one, balsam of Peru and botanicals are the most common allergens that cause facial dermatitis, O’Connell said. Nickel, which is the most common contact allergen overall worldwide, is next.
“It’s estimated that it affects between 9% and 18% of the general population, and it’s frequently mixed with other metals,” she said. “It can be difficult to sort out. It’s found in jewelry, clothing fasteners and obviously various other metal products. But also foods.”
Lanolin, which can be found in commercial moisturizers, is another common cause. Tosylamide formaldehyde resin, which is in nail polish, and methyl methylacrylate, found in customized nail products, cause facial dermatitis via ectopic transfers.
Lateral cases of facial dermatitis affecting the pre-auricular and lateral neck and jaw areas are likely due to shampoos and conditioners with CAPB, PPD hair dye or as they are rinsed off the scalp.
Cosmetics probably cause facial dermatitis affecting the forehead, cheeks, chin and nose.
“We’re rubbing those things heavily into the cheeks or into the forehead,” O’Connell said. “But it could also be due to moisturizing creams or anti-aging creams.”
O’Connell said that patients who wear jewelry may see gold leach into their personal care products and then unknowingly apply that gold to their face.
Allergic contact dermatitis that affects the entire face may be due to cosmetic products that treat the whole face such as foundations or face washes. Aeroallergens also may be a culprit, O’Connell said, although they would spare the nose. Photoallergenic causes may be in play too, although they would spare the upper eyelids.
The eyelids
Allergic contact dermatitis is one of the most common causes of eyelid dermatitis, O’Connell said, affecting or causing 81% of cases.
“That makes sense, because the eyelids are thin. They’re dense with blood vessels and lymphatics. They’re in constant motion,” she said.
Patients also are constantly applying chemicals to their eyelids in addition to ectopic transfer of allergens as they touch their eyelids with their hands and fingertips.
“The practice parameters recommend evaluating for allergic contact derm in patients with a facial rash with preorbital involvement,” O’Connell said.
“Highly allergic contact derm occurs more often naturally after an allergen is applied to the scalp or to the face rather than applied to the eyelids itself,” she continued. “While it’s really tempting to think that your patient’s eyelid rash is due to their eyeliner, it’s actually more likely to be a shampoo or conditioner causing it.”
However, O’Connell noted that airborne allergens also may be a cause.
Fragrances are the most common cause of eyelid dermatitis, followed by balsam of Peru, botanicals and nickel. Nail product chemicals including tosylamide formaldehyde resin and acrylates also are common causes.
Ingredients in ophthalmic products contact lens solutions and eyedrops such as benzalkonium chloride and thimerosl are unlikely causes of eyelid dermatitis.
Cases involving the upper and lower eyelids alike may be caused by shampoos and conditioners. Cases involving the upper eyelids only also may be caused by shampoos and conditioners, but O’Connell said that these cases probably are irritant contact dermatitis.
When the eyelids and face both are affected, O’Connell said, facial cleansers are likely the cause.
“We rub our facial cleanser into our cheeks or into our forehead,” she said. “Then when it gets rinsed off, it affects the upper and lower eyelids as well.”
Cases involving the scalp, forehead and eyelids are probably due to hair products such as dyes, bleach, styling gels, sprays and mousses.
When patients present with dermatitis on the eyelids, face and neck, O’Connell said, it most often is due to transferred allergens from fingernails or jewelry, especially when the dermatitis is bilateral but not symmetrical.
“Anytime you see that with dermatitis, you should be thinking about potentially ectopic transfer,” she said.
The lips
Lip dermatitis presents with burning, itching, erythema, edema and fissuring.
“It’s awful. All of our patients hate it. It’s really burdensome for them,” O’Connell said.
Allergic contact dermatitis on the lips usually does not spare the vermilion border, she continued. It also usually extends to the peri-oral skin but spares the oral mucosa.
“Those may be some hints,” she said.
Approximately 34% to 38% of lip dermatitis is atopic contact dermatitis confirmed by patch testing, O’Connell said, and it is more common among women, accounting for 85% of cases.
Fragrance, balsam of Peru and nickel are the most common causes of allergic contact dermatitis on the lips, in addition to other causes that are not included in standard patch testing, which O’Connell called frustrating.
“Patch testing sometimes doesn’t help us here, but that’s because we’re putting things into our mouth that we don’t put onto our skin,” she said.
Examples include menthol and spearmint.
“It’s important to have that idea of what you’re looking for before you patch test so you can order ingredients if you need to,” she said.
Finally, O’Connell noted that chronic oral mucosal irritation probably is not allergic contact dermatitis.
“I will get referrals for patients with burning mouth syndrome and recurrent aphthous ulcers,” she said. “But it’s important to know that chronic oral mucosal irritation is actually unlikely to be due to allergic contact derm.”
For more information:
Heather O’Connell, PA-C, can be reached at hroconnell@gmail.com.