Answers to common questions about allergic diseases and the atopic march.
An allergy is an immunological response to a normally harmless substance. When an allergen is introduced to the body, the immune system views it as a threat and issues a response. The location of the response—such as in the intestines, lungs or skin—determines the type of allergic disease that develops.
An allergen is the substance that triggers an immune response. Common allergens include dust, pollen, dander and some foods.
The atopic march, also referred to as the allergic march, is the observation that one allergic disease predisposes a person to the development of other allergic diseases. Atopic dermatitis, or eczema, is often the first step in the allergic march. Approximately 50 percent of children who develop eczema go on to develop other allergic diseases.
Asthma is a chronic condition that results in inflammation of the airways and decreased lung function. Symptoms include difficulty breathing, coughing, wheezing and tightness in the chest.
Although the mechanisms are not fully understood, experts agree that the development of allergic disease is based on both genetics and environment. One of the biggest predictors of whether a child will develop allergic disease is whether a parent (particularly a mother) has allergies. There are specific genes mutated at a high frequency in patients with atopic dermatitis. Environmental factors can include other bacteria and viruses the infant is exposed to, as well as pollution and particulate matter.
Allergic diseases are among the most common types of chronic disease and more than 50 million Americans are affected by allergic diseases. Ten-twenty percent of infants will develop atopic dermatitis. There are almost 10 million children in the US that have asthma. More than 5 million kids in the US have food allergies.
Maybe. Often the most severe symptoms occur during childhood. Many food allergies that develop in children can fade over time. As children age, other allergic symptoms can become less severe, which may be due to changes in immune responses to allergens. However, some patients have allergies their entire lives, and some adults develop allergies that they did not have as children.
Recent studies suggest that early introduction of peanut to infants that are not reactive will decrease their likelihood of developing peanut allergies later in life. This might be true for other foods too. Discuss this with your pediatrician or allergist to make an informed decision.
Reactions to wheat can be an allergy. In contrast, Coeliac disease is an autoimmune disease, not an allergy, that results from consuming wheat. The immune basis of gluten sensitivity is not yet clear, but it is unlikely that gluten sensitivity an allergic disease. Allergies are optimally defined by an allergist, and the best protection from known allergens is avoidance.
Tolerance built up by repeated exposure through allergy shots and other methods, is an effective therapy for some patients. While current treatments are effective for most people in alleviating an allergic reaction, treatments can be totally ineffective in others.
Currently, there are no adequate therapies for totally inhibiting allergic reaction or curing allergic disease.