Skin patch tests may help patients with eczema identify topical ingredients that are aggravating the skin as well as the type of eczema they have, according to an article published in SELF. Experts told the magazine that eczema refers to a group of seven conditions—including atopic dermatitis and contact dermatitis—characterized by inflammation of the skin. Individuals may be at higher risk for developing atopic dermatitis if they have a genetic predisposition for a filaggrin protein deficiency. However, the experts explained that contact dermatitis—a form of eczema not rooted in genetics—is based on direct contact with allergens from the environment that results in skin irritation. They suggested that individuals who experience rashes or scaly and itchy skin that doesn’t improve or is outside of the usual areas that afflict patients with atopic dermatitis—typically behind the knees, in the creases of the elbows, and on the hands and face—may benefit from patch testing. Experts said that certain beauty products and jewelry can also incite contact dermatitis flare-ups on the neck and ears, another sign that an individual may need a patch test to receive a proper diagnosis and treatment plan.
When undergoing a patch test, dermatologists will place up to 80 stickers containing traces of chemicals, metals, natural oils, fragrances, and other ingredients on the individual’s back. After 2 days—in which the individual will be advised not to sweat profusely or shower—they will return to have their reactions assessed. A second follow-up 2 days later will confirm the results and examine any additional reactions to the ingredients in order to provide the individual with a full list of their allergens. Patch tests may help them uncover the source of their contact dermatitis and avoid certain allergens; however, if the patch test reveals a lack of allergic reactions, the individual may only have atopic dermatitis. Experts stressed that anyone experiencing symptoms of eczema should make an appointment with their dermatologist to discuss whether a patch test can help them better diagnose and manage their conditions.