What do I need to know about food allergies?
Food allergy occurs when the body’s IgE antibodies react to food proteins. The IgE antibody identifies this food protein as an invader hence causing mast cells (cells that are located throughout our body like skin, digestive system, esophagus, lungs, nose) to release histamines.
Histamines cause the range of symptoms like itching, hives, coughing, lips/throat/face swelling, sneezing, wheezing, diarrhea, and vomiting. This response can escalate to become anaphylaxis—a severe reaction that may cause airway constriction, extreme blood pressure drop and death. There is NO cure for food allergies at this time.
Lactose intolerance is NOT a food allergy but a condition caused by a deficient enzyme that breaks down lactose found in dairy products. Celiac disease is NOT a food allergy as it is a lifelong autoimmune reaction that attacks its own tissues in the digestive system; wheat, barley, rye and oats are all glutens that are to be avoided by celiac individuals.
What is the treatment for food allergies?
The only treatment for food allergies is to prevent any reaction by strict avoidance of food allergens. To treat a reaction that is severe, an injection of epinephrine using an auto-injector called an Epipen® can prevent death by stopping the anaphylaxis and thus reducing the symptoms. Concurrent food allergy and asthma increases the severity of a food allergic reaction. Timely treatment of a reaction is crucial.
Based on statistics here in Singapore as well as the US, Australia and UK, food allergy is the leading cause of anaphylaxis. Top food allergens, based on US, Australia and UK research include: milk, egg, wheat, soy, peanut, tree nuts, seafood, crustaceans, and sesame (with mustard and celery added in UK list). According to statistics from aforementioned countries, 6-8% of children under 3 years old have food allergies. Those with milk, egg and soy allergy will most likely outgrow their allergies by age 10; whereas those with peanut, tree nut, seafood and crustacean allergy may expect lifelong reactions.
How are food allergies diagnosed?
At this time there are ONLY two tests that can help diagnose one with food allergy: Skin prick test (SPT) and the blood test known as RAST or ImmunoCapRast. Both of these tests are available in Singapore and should only be done by a GP or certified allergist.
The results of the diagnostic tests will NOT predict the severity of a reaction; rather the results will predict if a reaction will occur. The best diagnostic tool for allergists is the patient history. If a visit to an allergist is planned, provide the allergist with a food diary and corresponding reactions if possible. An Epipen© can only be dispensed with a doctor’s prescription. The IGG test is NOT accepted for food allergy testing.
What happens after food allergies are diagnosed?
Once a child is diagnosed with a food allergy, the family will undergo major lifestyle changes. According to a study, families with a food allergic child deal with more stress than those with epileptic or asthmatic children. However, a normal lifestyle can be achieved by following simple guides:
• AVOID food allergens: NO amount, not even a trace amount, is acceptable.
• READ labels: take time in the grocery to read the ingredient list. Learn the alternative names for the allergen. For example, peanut oil is also known as arachis oil—and can be found in sauces, salad dressings, and even dog food! AVOID bakery items as cross-contamination is high. If in doubt, DO NOT consume anything without reading an ingredient label. NEVER assume.
• PRACTICE the emergency plan: create a plan to know when to administer antihistamine or an Epipen© with your allergist. Have all family members know their role during an emergency—including the help at home. Know which hospital is closest, both at home and school. Update this information regularly.
• Teamwork: school, teachers, nurses, caregivers and child. Everyone has their own responsibility. Make sure a school policy is in place and the emergency plan can be followed at school. Empower your child with knowledge and make sure they understand the rules of not sharing food nor eating anything offered. Class or school training on food allergy awareness is essential. EVERYONE, all school staff, should know what to do in case an accidental ingestion occurs.
• Join our support group to learn to cope, to share and understand more about food allergies through other families dealing with the same everyday issues AND a 24-7 internet support group www.kidswithfoodallergies.org. Schools with food allergy support groups here in Singapore include: Unite World College of Southeast Asia, Australian International School, Singapore American School.
Currently major research is underway to find a cure. Perhaps as soon as two to five years from now, a cure will be available where anti-IgE therapy will be able to shut down the whole allergy system for food allergies.
Resources:
Scott H. Sicherer, MD, Anne Muñoz-Furlong, BA*, Ramon Murphy, MD, Robert A. Wood, MD|| and Hugh A. Sampson, MD. Symposium: Pediatric Food Allergy. PEDIATRICS Vol. 111 No. 6 June 2003, pp. 1591-1594.
FAAN (2005) Public Comment on 2005 Food Safety Survey: Docket No. 2004N-0516 (2005 FSS). Fairfax, VA, USA: Food Allergy & Anaphylaxis Network
FAAN. Impact of Food Allergy on Quality of Life. Food Allergy News, Vol. 9, No. 4
Chiang WC, Kidon MI, Liew WK, Goh A, Tang JP, Chay OM. The changing face of food hypersensitivity in an Asian community. Clin Exp Allergy. 2007 Jul;37(7):1055-61.
Thong BY, Cheng YK, Leong KP, Tang CY, Chng HH. Anaphylaxis in adults referred to a clinical immunology/allergy centre in Singapore. Singapore Med J. 2005 Oct;46(10):529-34.
Khoo J, Shek L, Khor ES, Wang DY, Lee BW. Pattern of sensitization to common environmental allergens amongst atopic Singapore children in the first 3 years of life. Asian Pac J Allergy Immunol. 2001 Dec;19(4):225-9.
Shek LP, Lee BW. Food allergy in children-the Singapore story. Asian Pac J Allergy Immunol. 1999 Sep;17(3):203-6. Review.
Hadley, Caroline. 2006 Food allergies on the rise? EUROPEAN MOLECULAR BIOLOGY ORGANIZATION. VOL 7. NO 11. 1080–1083 (2006)
Raymond J Mullins. Paediatric food allergy trends in a community-based specialist allergy practice, 1995–2006. The Medical Journal of Australia . Volume 186 Number 12. 18 June 2007.
