Elaine Siegfried, MD: We don’t really use the terms acute, subacute, and chronic when we’re talking about atopic dermatitis. There’s just not a clinical correlation to classifying it that way. Maybe some authors have done that. I certainly don’t use those terms very much. But disease waxes and wanes so it’s a chronic disease, but it goes through periods of flare and remission, and flare and remission, and again, we don’t know what causes those flares, but those flares happen pretty quickly. And when I say pretty quickly it’s probably over a course of days and they last over a course of days to weeks in the flare period.
When children are having those kind of flares, it frequently drives them to the emergency department and urgent care centers, and in some cases, children are admitted to the hospital. I think that really varies on what the resources are in any location because taking care of children in the hospital who have severe acute flares requires very specialty care and you have to know how to do it.
The low-grade kind of what you might refer to as subacute is something that really affects most children, especially children who have more than just mild disease, because they always have disease, they’re never clear. The worst they are is up here, and clear is the floor. They might get here and then they’re sort of happy because they’re suffering most of the time when they’re up here. That happens to children who have moderate or moderate-to-severe disease, they never quite clear but they’re always having smoldering disease.
Then chronic disease is just atopic dermatitis that doesn’t clear, and that happens in a pretty good proportion of people, but for some children and families they tolerate having that kind of disease for years and years. And now we’re finding out the impact of that. If you have smoldering disease, that’s low-grade, chronic, especially if it interferes with sleep, and that’s the big parameter that’s important to how much it interferes with your sleep. And if it interferes with sleep, we now know that that has significant repercussions on growth and development and learning, and it’s sort of a silent morbidity that happens with this disease. That’s really the best reason to recognize it and treat it.
Julie Block: Children with atopic dermatitis experience extreme itching if they have moderate and severe disease and flares on their skin, and sometimes they scratch themselves bloody. You know it’s time to see your physician if that is the case, and those are primarily the triggers. Again, it’s a skin rash. We call it the itch that rashes, and for children sometimes it begins in infancy, and many times children grow out of it. But if they don’t, they are generally set with their pediatrician early on in infancy or as toddlers and see their practitioner. And sometimes, depending on the severity of their disease, they will be referred to a specialist, a dermatologist, or an allergist perhaps.
Children with atopic dermatitis can be diagnosed with mild, moderate, or severe disease. It is based on their body surface area that is covered, their other comorbidities that they may have, such as asthma, allergies. And so it does go in and out. You can be somewhat managed and your disease may be considered mild and then it can flare up again and it can vacillate between those stages. But generally, if you’re moderate to severe, you’re staying in that lane, and you require great interventions and treatments.
Elaine Siegfried, MD: Atopic dermatitis is a clinical diagnosis, we don’t have a biomarker, we don’t have a blood test. It’s just based on early age of onset, distribution of disease, intense itch. A family history plays a role as well. So people who have a family history of asthma and hay fever and allergies is an important diagnostic factor. But the distribution is really what really gives you the most information. And that changes over time, so between infants and young children and adolescents, the areas that are most involved, change. But classically and the most characteristic distribution is antecubital and popliteal fossa. Face is involved and hands and feet are involved, especially as you age. We don’t really know why that is, but work with microbiome—those are the germs that grow in your skin—probably points to some of the reasons for that distribution.
Atopic dermatitis is a phenotype, so diagnosing the disease is based on clinical criterial. And because it’s such a common disease in children, people often overlook other things that kind of mimic atopic dermatitis. And that can be a problem, and it’s also a problem in terms of studies, like looking at the epidemiology and how it comes and goes. You have to know what true atopic dermatitis is to get an answer like that.
But what kind of other diseases are mistaken for atopic dermatitis? When babies have onset of generalized redness and scaling, if they’re otherwise healthy, they can have seborrheic dermatitis or psoriasis, or atopic dermatitis, or contact dermatitis. Those all kind of look like generalized redness and scaling with itch. And it takes a little while for them to evolve into a more classic phenotype of atopic dermatitis, again based on the distribution and the chronicity.
We don’t do blood tests for it typically to make the diagnosis. But as children get older, their clinical presentation fits the pattern of atopic dermatitis with antecubital and popliteal fossa involvement and intractable itch that interferes with sleep; it sort of becomes clear at that point.
Julie Block: Children with atopic dermatitis in their spectrum of care are first primarily seen by their pediatrician, and they again, depending on the severity of their disease, will be referred to a dermatologist, or a pediatric dermatologist, or an allergist, or a pediatric allergist. Those are the most common specialties that see children with atopic dermatitis.