Feb 21, 2012

The Atopic March

The term “atopic march” refers to the natural history of atopic manifestations, characterized
by the typical sequences of immunoglobulin E (IgE) antibody responses and clinical symptoms that appear during a certain age period, persist over years and decades, and often show a tendency for spontaneous remission with time.

Prospective cohort studies have shown that sensitization to food allergens occurs usually during the first months of life with the antibody response to cow’s milk and hen’s egg occurring most frequently. Sensitization against inhalant allergens usually develops after the first 2 years of life. Most of these children will develop IgE responses to a wide array of environmental allergens such as house dust mites, animal dander, and pollen.

Specific patterns of atopic sensitization are associated with certain atopic illnesses. Atopic eczema is primarily related to IgE responses to dietary allergen, while individuals with allergic rhinitis tend to become sensitized to seasonal outdoor allergens. Specific IgE responses in asthmatic children are usually directed against perennial and indoor allergen such as house dust mites. Several studies have shown that early sensitization during infancy is a predictor for the persistence of childhood asthma until adolescence.

In the German Multicenter Allergy Study, food sensitization before age 1 to 2 years with or without concurrent inhalant sensitization was a strong predictor for the development of asthma and airway hyper-responsiveness until school age.
Our understanding of the determinants of the natural history of allergic diseases is limited. Although a strong genetic basis for atopy and asthma has been described and several genes have been identified, which are associated with different phenotypes, a variety of modifiable environmental and lifestyle factors have been discovered in the past, which might offer future options for primary prevention.

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