The atopic march, sometimes called the allergic march, refers to the progression of allergic diseases, from atopic dermatitis, or eczema, early in life to asthma or hayfever in the later months or years. In some children, one allergic reaction ends before another begins. In other children, these allergic reactions overlap, for example, a child might have both eczema and asthma.
The Different Stages
Typically, the “march” begins early in a child’s life, showing up somewhere between birth and five years of age. This appears as a skin rash, called eczema or atopic dermatitis. It can continue throughout a person’s life. In infancy the rash is most often on the face and scalp. It is a red, crusting rash and can be itchy. After puberty, the rash is most commonly found in the folds of the elbows and knees but might also appear on other parts of the body, including the face, neck and upper trunk. It looks like a thickening
According to AllergyUK.org, the next step in the march is the appearance of food allergies. However, not all children will develop allergies to foods.
Allergic rhinitis, also called hayfever or allergies, is the third step in the atopic march. This is an inflammation of the nose with symptoms such as sneezing, runny nose, stuffy nose, itching and post-nasal drip. Some people also experience inflammation and itching of the eyes. Some of the most common allergens are dust mites, pollen, cats and dogs.
The final step of the atopic march is asthma. During an asthma attack, the small airways in the lungs become inflamed and narrow, making it difficult to get air in and out of the lungs. Allergens that trigger hayfever, such as dust mites, dogs and cats can also trigger asthma attacks. It is most often treated with an inhaler. Between 50 and 70 percent of children with severe atopic dermatitis go on to develop asthma.
Causes of the Atopic March
The medical community isn’t quite sure what causes the progression from atopic dermatitis to asthma. It could be that an immune disorder is the underlying problem, causing all of the different allergic reactions. According to this theory, the immune system overreacts to allergens, causing the rash, stuffy nose or inflammation of the lungs. Another theory is that the early skin condition - atopic dermatitis or eczema - sets off a further reaction, triggering the overactive immune response.
One study, completed in 2009 at the Washington University School of Medicine in St. Louis, showed that damaged skin from atopic dermatitis releases a substance into the body, which triggers an immune reaction. As this substance reaches the lungs, it causes asthma.
The scientists are planning further studies to determine if treating eczema early can stop the release of the substance or if there are ways to block the body from releasing the substance, therefore stopping the atopic dermatitis from marching forward.
“The Allergic March,” 2007, Sept. Ulrich Wahn, World Allergy Organization
“The Atopic March: Progression from Atopic Dermatitis to Allergic Rhinitis and Asthma,” 2011, April, Ta Zheng et al, Allergy Asthma Immunology Res
“Skin Derived TSLP Triggers Progression from Epidermal-Barrier Defects to Asthma.” 2009, Demehri et al, PLOS Biology
Published On: June 12, 2014