LAS VEGAS – Skin manifestations of nutritional deficiencies are likely underrecognized, according to Dr. James Treat.
“If you can recognize them, they’re incredibly satisfying and simple to treat,” he said at a pediatric update sponsored by the American Academy of Pediatrics California District 9. “You don’t have to prescribe medications; you simply have to replete in most cases.”
At-risk populations include children and adolescents on restrictive diets for conditions ranging from autism spectrum disorders to extreme or overdiagnosed food allergy, and eating disorders. “There are also kids with metabolic diseases and genetic defects that can lead to nutritional deficiencies,” said Dr. Treat, a pediatric dermatologist at Children’s Hospital of Philadelphia.
Dr. James Treat
Widespread, “flaking paint” dermatitis is a common hallmark of nutritional deficiency. Clinical patterns of typical eczema include antecubital fossae, popliteal fossae, and affected areas of the neck. If only the cheeks are involved in teething, the culprit is most likely irritation from drooling. “I call it drool dermatitis,” Dr. Treat said. “Food allergy leading to skin irritation and breakdown of the skin on the face is not the typical pattern of what food allergy does. Food allergy usually leads to more of a type 1 hypersensitivity where you get urticarial lesions or you get waxing, redness, or swelling.”
Food allergies are more common in children with atopic dermatitis, but they may not be the root cause of the atopic dermatitis. Skin prick testing and IgE food testing have excellent negative predictive value but limited positive predictive value, yielding high false-positive rates. “This matters, because we see kids who are labeled allergic to many foods based on large screening panels,” Dr. Treat said. “Some of them may be false positives, and it is difficult to tell for sure without corroborating parental history.” In fact, children can occasionally develop Kwashiorkor (protein deficiency) from parents restricting what they eat based on allergy-testing results if they are not taught to eat a rounded diet that is nutritionally replete while still avoiding their allergens.
If a child presents with eroded and crusted plaques defined by a “heaped-up” border, think zinc deficiency. The plaques can appear in the diaper area but also in the acral and perioral areas, with relative sparing of the upper lip. He used the mnemonic “diaper” in listing clinical clues: diaper, irritability, acral location, photosensitivity, erosive and crusted appearance, and response to topicals that is poor.
The work-up should consist of measuring zinc and alkaline phosphatase levels in the children. If the child is breastfeeding, Dr. Treat recommended checking zinc levels in the breast. “If mom is missing a zinc transporter in her breast, she can actually have normal zinc levels but not get them into breast milk,” he explained. “You can also have a child who’s missing the zinc transporter in their own gut, or you can have kids who are drinking milk a bit early and some of the zinc-binding proteins in the milk bind the zinc so that it doesn’t get absorbed.” Conditions to consider on your differential include cystic fibrosis or fructose/sucrose malabsorption.
“Kids with severe atopic dermatitis may need a little extra zinc,” he said. “We don’t usually replete it by giving them zinc, but we make sure they’re using appropriate formula or breast milk or that they’re taking a multivitamin with a little zinc in it. Anytime you turn the skin over consistently, you often need a lot of zinc.” Mimickers of zinc deficiency include biotinidase deficiency, methylmalonic acidemia, propionic acidemia, maple syrup urine disease, citrullinemia, and ornithine transcarbamylase deficiency.
Dr. Treat reported having no relevant financial disclosures.
On Twitter @dougbrunk