Food Allergy in Charlottesville

Individuals with food allergy have an overreactive immune system towards a particular food. Such a response happens due to an antibody called IgE (Immunoglobulin E). Individuals suffering from food allergy often have a family history of allergies. The most common food allergens are the proteins in cow's milk, eggs, peanuts, wheat, soy, fish, shellfish and tree nuts.

The symptoms on food allergy may not depend on the amount of allergenic food consumed and may even happen with consumption of tiny amounts. It is also important to note that many allergens may cause symptoms even after they have been cooked, and even after undergoing the digestive process. On the other hand, some other allergens, typically certain fruits and vegetables, may only cause allergies when consumed raw.

In some food groups, such as seafood and tree nuts, a phenomenon called cross-reactivity may be seen. This implies that if an individual has an allergy to one member of a food family, they may also be allergic to other members of the same food group. Interestingly, cross-reactivity may not be as commonly seen in foods from animal groups. For example, it has been found that individuals who may have allergies to cow's milk may still be able to eat beef. Similarly, individuals with egg allergies may still be able to eat chicken. It has also been found that among shellfish, crustaceans (shrimp, crab and lobster) are most likely to cause an allergic reaction. Other mollusks such as clams, oysters and scallops are somewhat less commonly associated with allergies.

Symptoms of Food Allergies:
Symptoms of allergic reactions are commonly dermatological in nature and may cause skin itching, hives and swelling. Vomiting and diarrhea are common gastrointestinal symptoms. Symptoms of the respiratory system usually occur only in conjunction with skin and gastrointestinal symptoms.

Severe Allergic Reactions:
Anaphylaxis is a serious allergic reaction that happens very quickly and needs immediate and urgent attention! The symptoms often include difficulty in breathing, loss of consciousness and dizziness. If you notice any of these symptoms, especially after eating, call 911 rightaway. It is imperative to seek medical care immediately (call 911). Don't wait to see if your symptoms go away or get better on their own. Without immediate treatment and effective and expert medical care, anaphylaxis can be lethal. It is essential to follow up with your allergist in such cases.

Diagnosis:
An allergist is the best qualified professional to diagnose food allergy. Your allergist will take a thorough medical history, followed by a physical examination. You may be asked about contents of the foods, the frequency, seasonality, severity and nature of your symptoms and the amount of time between eating a food and any reaction.

Allergy skin tests may determine which foods, if any, trigger your allergic symptoms. In skin testing, a small amount of extract made from the food is placed on the back or arm. If a raised bump or small hive develops within 20 minutes, it indicates a possible allergy. If it does not develop, the test is negative. It is uncommon for someone with a negative skin test to have an IgE-mediated food allergy.

In certain cases, such as in patients with severe eczema, an allergy skin test cannot be done. Your doctor may recommend a blood test. False positive results may occur with both skin and blood testing. Food challenges are often required to confirm the diagnosis. Food challenges are done by consuming the food in a medical setting to determine if that food causes a reaction.

Another question that is commonly asked is whether children outgrow their food allergies. It has been reported that most children may outgrow  certain allergies such as those to soy, egg, cow's milk, and wheat allergy, even if they have a history of a severe reaction. About 20% of children with peanut allergy will outgrow it. About 9% of children with tree nut allergy will outgrow it. Your allergist can help you learn when your child might outgrow a food allergy.

Treatment:

The best way to treat food allergy is to avoid the foods that trigger your allergy. Always check the ingredients when eating, especially when out of home. Carefully read labels that indicate food information.

Carefully read food labels. Always carry and know how to use injectable epinephrine and antihistamines to treat emergency reactions. Teach family members and other people close to you how to use epinephrine! It is also important to wear an ID bracelet that describes your allergy.

Food allergies can be confusing and isolating. For support, you may contact the Food Allergy & Anaphylaxis Network (FAAN) at (800) 929-4040.

(Information only; not intended to replace medical advice; adapted from AAAAI)