SAN FRANCISCO — Atopic dermatitis is a multifactorial disease requiring multimodal treatment, Jeffrey Sugarman, M.D., said at a meeting on clinical pediatrics sponsored by the University of California, San Francisco.
Dr. Sugarman of the university offered a number of tips to assist the clinician in treating atopic dermatitis (AD), the key dermatosis in children:
▸ Be sure of the diagnosis. “Pruritus is a universal feature,” Dr. Sugarman said. “If your child with atopic dermatitis is not itchy, you may want to rethink the diagnosis.”
▸ Barrier dysfunction contributes to AD, and the barrier is typically abnormal, even in nonlesional skin. This results in an increased permeability to bacterial pathogens, allergens, and nonspecific irritants.
▸ Gentle skin care is important, and one way to accomplish that is to use a cleanser with a neutral or slightly acidic pH. Surprisingly, some popular cleansers, even those marketed for infants, have highly alkaline pH, which exacerbates barrier dysfunction. (See chart.)
▸ Recommend the use of emollients, hydrophobic lipids that replace or supplement subcutaneous lipids. These form a temporary hydrophobic shield on the surface, which promotes immediate barrier repair.
▸ Most emollients, such as petrolatum and lanolin, are nonphysiologic and have a limited duration of benefit (less than 6 hours).
Physiologic lipid emollients, which now are coming on the market, contain correct molar ratios of ceramide, cholesterol, and free fatty acids.
The skin handles physiologic emollients differently than their nonphysiologic counterparts. Physiologic emollients are taken up by keratinocytes, packaged into lamellar bodies, and resecreted to form lamellar bilayers.
TriCeram is one such emollient that's already on the market, and Dr. Sugarman expects others to become available soon. Unfortunately, the high price of TriCeram will put it out of the reach of many patients, he said.
▸ “Drooling dermatitis,” AD around an infant's mouth, is caused by mechanical irritation in messy eaters from nursing or the bottle. Tell parents to keep the barrier up by applying Vaseline or Aquaphor on the perioral skin before meals. Assure them that drooling dermatitis will disappear as the infant gets older.
▸ A child or adolescent who has had “athlete's foot” that has not responded to topical antifungals may actually have juvenile plantar dermatosis or “toxic sock syndrome,” he said.
These children typically will have sweaty feet and a history of atopic disease. Look closely at the bottom of the feet. Juvenile plantar dermatosis is characterized by inflammation on the weight-bearing surfaces of the big toes.
The web spaces are spared, which is the opposite distribution you would see from a fungal infection. Treatment includes a frequent change of socks and the use of emollients and a mid-potency steroid cream.
▸ To minimize pruritus with AD, recommend warm—not hot—baths, and avoid overheating. Keep the body covered with soft, non-wool clothing. Use emollients. Hydroxyzine is Dr. Sugarman's favored antihistamine, at a dose of 1–2 mg/kg per day.
Consider rotating antihistamines, such as cyproheptadine, doxepin, and diphenhydramine, if one stops working. Topical diphenhydramine is of little use, and the newer nonsedating antihistamines also appear to be relatively ineffective in reducing pruritus.
▸ For decades, the use of intermittent topical corticosteroids has been the standard of care for AD, despite their well-known side effects including burning, redness, dryness, and thinning of skin with long-term use.
▸ Topical calcineurin inhibitors (TCIs) such as tacrolimus and pimecrolimus also work, and are especially valuable for intertriginous and eyelid lesions. They decrease the need for topical corticosteroids and improve quality of life.
The FDA apparently is concerned about the potential risk of cancer with long-term use of TCIs, but Dr. Sugarman said they're safe if used properly.
They should be reserved for second-line use for short-term and intermittent long-term use in AD. TCIs should be avoided in children younger than age 2 and in immunocompromised patients. Reinforce the need for adjunctive treatment such as gentle skin care, controlling itch, and treating infections. And advise parents that treated areas also need sun protection.