Allergies and asthma are two common childhood disorders. They are both conditions that are mediated by the immune system, and allergies can trigger asthma in many children. Asthma, according to the American Lung Association, is one of the primary causes of children missing school; in 2008, 14.4 million days of school were lost due to problems with asthma.
Allergens
Allergies and asthma commonly occur together, the Mayo Clinic explains. This is because both disorders are caused by exposure to substances called allergens. Allergens are compounds that are identified as being infectious, despite that allergens otherwise cause little or no damage to the immune system. When a child inhales these allergens, it can result in a condition known as allergic asthma.
IgE and the Immune System
Asthma and allergies are mediated by a special protein called immunoglobulin E, also known as IgE, the American Academy of Allergies and Asthma and Immunology explains. Immunoglobulins are proteins that are part of the immune system and bind to potentially infectious molecules. Children with allergies and asthma have IgE molecules that bind to allergens; when an IgE molecule binds to its target, it releases several chemical signals, including a chemical called histamine, which promotes inflammation. The immune systems of children are particularly sensitive to allergens because their body has not had as much time to learn which molecules are dangerous and which pose no health threat.
Symptoms
Allergies can cause a variety of symptoms, including an itchy or runny nose and inflammation of the nasal passages. When allergies trigger asthma, children may also have trouble breathing, and when they exhale, a characteristic wheezing sound may be heard. Frequently asthma can make sleep difficult because the child has trouble breathing at night. Asthma can also produce a chronic dry cough.
Testing
Allergy testing can benefit children who suffer from allergies and asthma. Allergy testing is commonly performed using what is known as the skin test. Skin testing involves placing several potential allergens on the skin and then using a small needle to prick the skin, causing the potential allergens to gain access to the tissue under the skin. If redness and swelling occur around the prick site after a few minutes, the substance is identified as an allergen. Identifying the allergens that trigger an allergic reaction can help children with allergic asthma know which things, such as pollen, dust mites or animal dander, to avoid. Avoidance of allergens can help children limit the frequency of allergy attacks.
Treatment
There are two main ways in which asthma is treated, the American Lung Association explains. Bronchodilators are inhaled medications that relax the muscles around the airway, allowing air to pass more easily in and out of the lungs. The other way of treating asthma involves suppressing the immune response that leads to the asthma attack; this can be done by using corticosteroids or other immune-modulating drugs, such as leukotriene modifiers and theophylline. Children with allergic asthma may also benefit from allergy shots, the Mayo Clinic explains. Allergy shots work by injecting small amounts of allergens into the child in order to desensitize the immune system.
