Finding contact dermatitis causes in women can be challenging

Key Points

Wailea, Hawaii - While common allergens cause most contact dermatitis in women, finding the sources of these allergens often demands detective work, an expert says.

In epidemiological studies that attempt to identify allergens most often responsible for contact dermatitis, he says, results vary depending on the population tested. However, throughout North America, "About one-third of the people patch tested are men; two-thirds are women (Zug KA, Warshaw EM, Fowler JF Jr., et al. Dermatitis. 2009 May-Jun;20(3):149-160. Erratum in: Dermatitis. 2009 Oct;20(5):300. Marks, James [added]). That tends to be consistent from study to study - women will be overrepresented," Dr. Cohen says. Gender aside, the hands and face represent two most common areas affected, he adds.

When it comes to the location of allergic reactions to cosmetic sources including soaps and haircare products, however, a recent study reveals a striking gender difference, Dr. Cohen says. Specifically, nearly half the women surveyed experienced at least one such reaction on the head and neck, versus 23.7 percent of men (Warshaw EM, Buchholz HJ, Belsito DV, et al. J Am Acad Dermatol. 2009 Jan;60(1):23-38. Epub 2008 Nov 6. Erratum in: J Am Acad Dermatol. 2009 May;60(5):840).

"That may reflect simply a usage phenomenon. Women are probably using more products, more frequently, on the head and neck, than men use," he explains.

Furthermore, he says that eyelid dermatitis represents "probably one of the more vexing problems that we deal with as dermatologists. When we test eyelid dermatitis in women, we average more than 100 allergens at a time," including a series of 60 to 80 standard allergens.

In a large cohort study of patients with pure contact dermatitis of the eyelid, gold, fragrance, balsam of Peru and nickel sulfate represented the most likely sources of positive reactions, with rates between 8.2 percent and 6.0 percent (Rietschel RL, Warshaw EM, Sasseville D, et al. Dermatitis. 2007 Jun;18(2):78-81).

When dermatologists find eyelid dermatitis, Dr. Cohen says, traditionally they have been trained to check whether patients use fingernail polish.

"But you'll probably be surprised at where nail polish fell along eyelid dermatitis culprits - 17th (1.5 percent)," he says.

Allergens it tied with included tixocortol pivalate, a screening chemical used to detect hydrocortisone allergies. Therefore, "Patients with eyelid dermatitis are as likely to be allergic to their nail polish as they are to the hydrocortisone they bought over-the-counter to treat it," he adds.