Ask the Expert: What Tests Can Help Determine Whether My Child's Eczema Is Caused By Allergies? By Philip Hemmers, D.O. February 11, 2013 Get Sanity Saving Ideas and Activities Subscribe Your child has itchy rashes on his skin. A doctor of the Allergy Center of Connecticut provides an overview of the types and safety of tests you can get on your child to see whether his eczema is caused by allergies. Approximately one in three children with eczema will have a food allergy. Unlike the symptoms of anaphylaxis (a more severe allergic reaction), eczema symptoms may occur hours or days after ingestion. This makes it difficult for parents to identify specific foods triggers. We must rely on allergy testing. The National Institute of Allergy and Infectious Diseases has recommended that children younger than 5 with moderate to severe atopic dermatitis be evaluated for allergies to milk, egg, peanut, wheat, and soy only if the child has persistent eczema despite adequate treatment or if the immediate reactions have occurred after ingestion of a specific food. Blood tests are often performed by the pediatrician as part of an initial screen for allergies. These tests measure the level of antibodies directed against specific foods. Antibodies are proteins made by the immune system to protect us from bacteria and viruses. An overactive immune system will produce the wrong antibodies (known as IgE) against the wrong proteins (harmless and nutritious foods). Blood test results must be interpreted correctly as they often over-diagnose allergy (by as much as 50 percent). The accuracy of this test is affected by age and the severity of disease. An allergy specialist may perform skin puncture testing. This simple test provides an accurate and fast result in children as young as 6 months. A small amount of food protein is placed under the skin, usually on the back or arms. Within 15 minutes a small welt (or hive) will appear under those foods that the child is allergic to. There is no risk for more severe reaction and the welts will resolve on their own. When questions persist, a food challenge may be necessary. This is the diagnostic gold standard. Suspect foods are removed from the diet and re-added after a period of observation. Depending on the likelihood of allergy, this challenge may be performed in the physician office. Generally, elimination and challenge requires more work and more patience. Some final tips: • Avoid unproven allergy tests. Among many others, this includes kinesiology testing, Namburipad’s Allergy Elimination Test, IgG testing, provocation and neutralization, pulse testing and the ALCAT test. • Do not remove foods, such as milk, wheat or eggs, without consulting your child’s physician. Dr. Philip Hemmers, a native of Long Beach, NY, is certified by the American Board of Allergy and Immunology to care for both children and adults. He practices at the Allergy Center of Connecticut with offices in Bridgebort, CT and Norwalk, CT. Dr. Hemmers earned a bachelor's in biomedical engineering from Duke University and attended medical school at the New York College of Osteopathic Medicine. He completed a pediatric internship and residency at Mount Sinai Medical Center and a fellowship training at Long Island College Hospital. Want more content like this? Like us on Facebook!