The Allergic March, also called the Atopic March, refers to the progression or development of various allergic conditions with age.
What is Allergic March?
Being prone to develop allergic conditions is a genetically inherited trait; however, the conditions or environment a child grows up in also affects the development of allergic conditions. The tendency to have an allergic condition, known as "atopy", makes one prone to develop other allergic condition which is one reason it is called the Allergic (Atopic) March. The 4 main allergic conditions are eczema (also called atopic dermatitis), food allergies, environmental allergies (also called allergic rhinoconjunctivitis or "hay fever" or just "allergies"), and asthma. These conditions and their symptoms often appear in a particular sequence with age, hence another reason for the term "march". BUT they can also overlap. For example a child with a food allergy can go on to develop environmental allergies before they have outgrown their food allergy. Although the term "march" also implies that there is a progression through each one of these allergic conditions, an individual may only manifest some of these allergic conditions through their lifetime. It's just that the allergic conditions that do end up developing tend to appear at particular ages in a sequence.
What are the symptoms and when do they appear?
Typically the first allergic condition to manifest is eczema which is a skin condition characterized by itchy rashes which come and go. Eczema most commonly develops between 2-12 months of age. About 30% of children with moderate to severe eczema develop a food allergy and this condition is typically next to develop, often between 6 to 12 months of age. Symptoms of food allergies include redness of the skin, rash or hives (welts), swelling of lips or eyes, vomiting, or breathing difficulty which occur in various combinations fairly quickly after eating the food (usually within 2 hours). Food allergies most commonly are due to one or more of the following: milk, egg, wheat, soy, peanut, tree nuts, fish, and shellfish. These foods account for 85% of food allergies in children. In a child who has eczema, there is an 85% risk of developing environmental allergies (hay fever). Environmental allergies can develop as early as 1 year of age to substances found indoors such as dust mites and pet dander. Allergies to pollen typically develop between 3 to 5 years of age at the earliest (after exposure to a few pollen seasons). Symptoms of environmental allergies include runny nose, frequent sneezing, itchy nose, blocked nose, or itchy, red, watery eyes. Finally, a child with eczema has a 50% risk of developing asthma which can manifest at 3 to 5 years of age or later. Asthma is a chronic lung disease characterized by inflammation (swelling and mucous) in the airways (breathing tubes) AND "twitchiness" of the airways causing them to constrict (narrow). When the airways constrict, symptoms of asthma occur and can include repeating coughing or wheezing (high pitched whistling noise with breathing) or chest tightness (a sensation where breathing seems constricted or difficult) or a combination of these. The symptoms of asthma can be triggered by colds (illness) or allergies.
When should treatment begin?
Doctors and other scientist are continually doing research to better understand the Allergic March. Hopefully a better understanding of the Allergic March can help us develop strategies to prevent allergic conditions from occurring and put a "halt" to the march. For example, studies have shown that starting a young child with environmental allergies on immunotherapy (allergy shots) can reduce the child’s risk of developing asthma. Additionally, new studies suggest that introducing some highly allergenic foods such as peanut earlier in life may reduce the risk of developing food allergies in children with eczema. To learn more contact your local Allergy Partners physician or visit allergypartners.com.
By Dr. Vaishali Mankad
Allergy Partners of Raleigh"