AD in Infancy: Diagnostic Advice and Treatment Tips

WASHINGTON — Atopic dermatitis (AD) in childhood presents most commonly by age 1 and typically begins on the face, and while it can make infants “miserable,” caregiver and provider concerns about treatment on the face and at such a young age mean it is often “woefully undertreated,” Robert Sidbury, MD, MPH, said at the annual Revolutionizing Atopic Dermatitis conference.

Dr Robert Sidbury

Identifying and mitigating triggers — such as irritation, contact allergy, and infection — is a cornerstone of treatment in infants, but tailored therapy with topical corticosteroids, topical calcineurin inhibitors (TCIs), and topical phosphodiesterase 4 (PDE4) inhibitors also have roles to play, said Dr. Sidbury, chief of dermatology at Seattle Children’s Hospital and professor in the department of pediatrics at the University of Washington, Seattle.

Dr Lawrence Eichenfield

Views on the use of dupilumab as a systemic agent for severe infantile AD, meanwhile, have shifted significantly in the past year with the Food and Drug Administration approval of the biologic for children aged 6 months to 5 years and with extended experience with the biologic in all ages, including children, Lawrence F. Eichenfield, MD, professor of dermatology and pediatrics at the University of California, San Diego, said at the meeting.

The pediatric dermatologists spoke during a session devoted to AD in infants, during which the diagnosis of AD and the role — and risks — of food allergy testing were also discussed. Diagnosis, said Elaine C. Siegfried, MD, who also spoke during the session, requires careful consideration of mimicking conditions and a broader list of differential diagnoses in those infants with poor growth or frequent infections.

Here are some of the experts’ pearls for practice.

Diagnosing AD in infants

Dr Elaine Siegfried

Among infants who are growing well and otherwise healthy, the infantile eczema phenotype encompasses AD, seborrheic dermatitis, contact dermatitis, psoriasis — and overlap of more than one of these conditions. “Overlap is common,” said Dr. Siegfried, professor of pediatrics and dermatology at Saint Louis University, and director of the division of pediatric dermatology at Cardinal Glennon Children’s Hospital.

(Initial topical treatment for all these conditions is similar, but optimal treatment may differ for young children with moderate to severe disease that requires systemic treatment, she said in an interview after the meeting.)

Sparing of the diaper area that reflects skin barrier integrity is a classic feature of AD in infants and can be a useful diagnostic sign. In addition, “hypopigmentation is more characteristic of psoriasis” than AD, whereas AD tends to be hyperpigmented, which is most obvious in skin-of-color patients, Dr. Siegfried said.

Disease-specific pigment changes may be related to microbial colonization — such as Malassezia-associated hypopigmentation — or cell turnover, which is faster in psoriasis and slower in AD — with corresponding differences in pigment retention, and may be more obvious in children than adults, she said.

A less common scenario is dermatitis in infants who are not growing well. For these patients, she noted, the differential diagnosis includes metabolic or immune deficiency dermatitis as well as a variety of genodermatoses.

Generalized redness and scaling present on the first day of life is suggestive of non-atopic dermatitis. “If you’re born with red scaly skin, that’s very different than if you develop red skin in the first month or two of life,” Dr. Siegfried said.

When there is diaper area involvement with AD, contact dermatitis, impetigo, and Candida may be complicating factors. And in infants with other morbidities — especially those who are not growing well — diaper area involvement suggests a broader differential diagnosis. “I implore you, if you see children, make sure you weigh and measure them at every appointment,” she said.

Dr. Siegfried has seen infants with Netherton syndrome, and those with cystic fibrosis with zinc deficiency, for instance, presenting with “an eczematous-like picture,” diaper-area involvement, and other morbidities.

For infants with AD, she maintains a high index of suspicion for secondary infections such as molluscum, herpes simplex virus (HSV) with or without streptococci, scabies, tinea, and group A streptococci. “Secondary infections…may be incognito,” she said. “Look for subtle signs. Even molluscum can be very subtle.”

Secondary allergic contact dermatitis is also common although it’s “technically difficult to confirm the diagnosis,” she said. Patch testing in infants is technically challenging, sensitivity is low, and monosensitization is uncommon. “So I do initial empiric topical allergen avoidance,” she said, keeping in mind ubiquitous and avoidable topical allergens such as Kathon, cocamidopropyl betaine, propylene glycol, disperse blue, and adhesives.

Treating AD in infancy

Irritation “is probably one of the biggest triggers” of AD in infants, and the often “pristine” diaper area compared with inflamed eczema elsewhere can demonstrate the importance of moisturization for healthy skin in atopic infants, Dr. Sidbury said.

Among treatments that “punch above their weight” for AD in infants is an ointment-based barrier applied around the mouth, chin, and chest — where the wet/dry impact of drooling is maximal — before and after meals, he said.

Another is hydrocortisone 2.5% mixed 1:1 with mupirocin for those infants who have secondary infections and “that exudative, weepy-looking appearance on the face,” he said. The topical antibiotic in the combination cream “lessens the potency of the steroid and oftentimes by synergy, makes it more effective” by simultaneously treating inflammation, he said. He cautions against products containing neomycin, which can be an allergen.

A combination antibiotic-steroid-emollient cream (the Aron Regimen) can also “sometimes punch above its weight,” Dr. Sidbury said.

Infections typically involve Staphylococcus aureus, but in up to 16% of cases Streptococcus is involved. And notably, lurking underneath the honey-colored crusting of S. aureus infections may be the grouped vesicles that characterize eczema herpeticum, Dr. Sidbury said.

“Counsel [parents] preemptively to treat cold sores immediately [in order to] decrease HSV shedding and minimize risk to their baby,” Dr. Sidbury said.

For treating AD-associated inflammation in skin not affected by secondary infections, over-the-counter 1% hydrocortisone cream is often sufficient, and “for very young babies and preemies in particular, I generally don’t use anything stronger because their skin barrier isn’t fully complete yet, so they absorb more than an older child does,” he said, referring to ages 2 months corrected as a marker for considering a stronger formulation if needed.

Many parents are “very concerned” about topical corticosteroid (TCS) use and pediatricians are also “often concerned,” Dr. Sidbury said. Addressing this concern, he tries to provide context and promote adherence by pointing out that infants have an easily visible vein at the temple area where the skin is naturally thin. If parents were to see this appearance for the first time in other areas while using topical steroids, he tells them, it may be the first sign of skin thinning, but “it’s entirely reversible at that stage.”

He also stressed the cost of not treating. It’s unknown whether “treating aggressively early on prevents any future development or manifestation of eczema, or future comorbidities, but we don’t know that it doesn’t,” Dr. Sidbury said. “And we certainly know how miserable that baby with eczema can be in the short term. So we need to use these medicines.”

Dr. Sidbury utilizes tacrolimus 0.03% ointment, a topical calcineurin inhibitor (TCI), only if he is worried about overuse of steroids, and uses a regimen that alternates the TCI (used in infants off-label because it is approved for ages 2 years and older) with TCS in periods of similar duration (for example, treatment with TCS for 1 week and TCI for 1 week, or rotations of 2 weeks each or 3 days each). “And these rotations may be dynamic depending on severity of the flare at any given time,” he said after the meeting.

Preapproval data from the pivotal trials of tacrolimus are reassuring and can be shared with parents. “Two-year-olds had 90% of BSA [body surface area] treated for 12 weeks” with no signs of systemic risks, Dr. Sidbury said at the meeting.

Crisaborole, a topical phosphodiesterase 4 (PDE4) inhibitor approved for AD down to age 3 months, does not, like tacrolimus, have a boxed warning about a possible risk for cancer, and may also be alternated with TCSs. It will cause stinging in some children, but TCSs and TCIs can also sting in some children, he said, noting that samples can be helpful to predict what will or won’t sting each infant.

Systemic treatment in infants

The Liberty AD PRESCHOOL phase 3 trial that supported the FDA’s approval of dupilumab down to 6 months of age, published in 2022 in The Lancet, covered ages 6 months to 5 years but included only six children under the age of 2, “leaving us with a very limited dataset in this age group,” Dr. Eichenfield said at the meeting.

Other data and analyses that have provided reassurance, such as a laboratory safety analysis published online in 2022 showing no meaningful changes in laboratory safety parameters in children as young as 6 months, and pediatric data (not including infants) presented at a RAD meeting in 2022 showing that dupilumab, an interleukin-4 receptor alpha antagonist, may have positive effects on bone mineral density.

Data from the Liberty AD PRESCHOOL open-label extension study presented at the American Academy of Dermatology meeting in 2023, meanwhile, show that “the adverse event profile is not looking much different than what we see in older children,” Dr. Eichenfield said. “There are low rates of severe adverse events and a very low rate of discontinuations.”

At Rady Children’s Hospital, where Dr. Eichenfield is chief of pediatric and adolescent dermatology, dupilumab has become a first-line systemic agent for severe infantile AD, supplanting prior traditional but little used systemic agents such as oral corticosteroids, cyclosporine, methotrexate, azathioprine, or mycophenolate, he said after the meeting.

The decision to use systemics in the first 2 years of life is “a comprehensive one,” requiring knowledge of the child’s history, disease course, and assessment of response to prior therapies, comorbidities and severity, he said.

Food allergy in infants with AD

Food allergy is common in children with moderate to severe AD, but true food-triggered AD, with AD being the only symptom of food allergy, is rare, said Anne Marie Singh, MD, associate professor in the division of allergy and immunology and rheumatology at the University of Wisconsin, Madison, who focuses on pediatrics.

Over the years, studies of double-blind placebo-controlled food challenge tests in children with AD have tended to conflate immediate IgE hypersensitivity (and skin symptoms like urticaria) with AD, said Dr. Singh, who directs the university’s Food Allergy Research and Education Center of Excellence. In a recently published study she led involving 374 children with AD referred to allergy and/or dermatology subspecialty clinics at the University of Wisconsin, Madison, 55% had a food allergy but only 2% had food-triggered AD “where eczema is the only symptom and removal of the food cleared up the eczema and its return brought it back,” Dr. Singh said at the meeting. Another 4% had combined IgE-mediated food allergy and food-triggered AD. Almost half of the children with food-triggered AD were under 1 year of age, and egg was the most common trigger, she noted.

Food should be implicated largely by history, Dr. Singh emphasized.

Food allergy testing in the context of AD can be done but is challenging, with the clinical relevance of skin prick testing and food-specific immunoglobulin E (sIgE) difficult to predict. Predictive values of sIgE levels are established for immediate IgE mediated food allergy, but “cut-offs” for food-triggered AD are not established, she explained, noting that “cut-offs are likely higher for our children with AD.”

Elimination diets, moreover, pose significant risks of future oral tolerance and risks of nutritional deficiencies and poor growth, Dr. Singh said. New and immediate reactions to foods that are reintroduced after an elimination diet are common, and research has shown that 20% or more of such reactions involve anaphylaxis. “If an elimination diet is undertaken, you need emergency action plans, injectable epinephrine, and nutrition counseling,” she said.

A recent systematic review and meta-analysis conditionally recommended against elimination diets for the treatment of AD, Dr. Singh noted.

Asked by Dr. Sidbury whether there “is a sweet spot where you can eliminate [foods] without going all the way,” Dr. Singh said she will sometimes do a “diagnostic elimination trial” with food elimination for 2-4 weeks only — a time period after which “I’ll feel really comfortable reintroducing the food.”

Dr. Singh urged dermatologists to “know your allergist” because “patients respond best with a consistent message.”

Dr. Sidbury reported ties with Regeneron, UCB, Pfizer, Leo Pharma, Lilly, and Beiersdorf. Dr. Siegfried reported ties with Pfizer, Regeneron, Sanofi Genzyme, Pfizer, UCB, Novan and Leo Pharma. Dr. Singh reported ties with Incyte and Siolta Therapeutics. Dr. Eichenfield reported ties with Pfizer, Regeneron, Sanofi Genzyme, Incyte, and Pfizer.

This article originally appeared on, part of the Medscape Professional Network.

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