Peanut allergy

• What is Peanut allergy?
• Statistics
• Risk Factors
• Progression
• Symptoms
• Clinical Examination
• How is it Diagnosed
• Prognosis
• Treatment
• References

What is Peanut allergy?

Food allergies, including allergy to peanuts and other nuts, can have effects at several different sites in the body, including the mouth, throat, lungs, skin and gastrointestinal tract. Often more than one site in the body is affected at the same time, and the reaction can be generalised, such as anaphylactic shock.

Statistics

Peanut allergy affects 1 in 50 children and 1 in 200 adults in Australia.³

Risk Factors

As with most allergic diseases, people with a personal or family history of other allergic diseases are more likely to develop peanut allergy. Research is ongoing to determine whether early exposure to peanuts increases or decreases the risk of developing peanut allergy in high risk children.

Progression

In most cases, peanut allergy and allergy to other nuts is lifelong. There have been some reports in the literature of patients who have developed a tolerance to peanuts and tree nuts over time.⁵

How is it Diagnosed

There are several methods of unorthodox “tests” for food allergy. Examples include cytotoxic food testing, Vega testing, kinesiology, iridology, pulse testing, Alcat testing and Rinkel’s intradermal skin testing. These are unreliable, have no scientific basis and have no useful role in the assessment of allergy.¹

Prognosis

Most cases of allergic reactions to peanut are mild. Skin reactions such as hives, eczema and vomiting are the most common complaints. Some sensitive individuals develop difficulty breathing due to asthma or throat swelling, or a drop in blood pressure. This is known as anaphylaxis, and allergy to peanuts is one of the most common triggers of anaphylaxis. In most people peanut allergy can be managed by avoidance of peanuts and foods containing peanuts.

Treatment

Management of confirmed peanut allergy is centred around avoidance of foods containing peanuts. Unfortunately, many foods and other products contain peanuts or peanut traces as they are widely used in both Western and Oriental cooking. Laws require that any product that may contain peanut traces be labeled as such. The following list of foods and products may contain peanuts or peanut traces, and it is important to carefully check the label before consuming these: Baked goods Biscuits Cereals Chinese meals Crackers Egg rolls Ice creams Health bars Indonesian dishes Kebabs Marzipan Mixed nuts Pastries Peanut oil “Natural” flavorings Peanut butter Sweets Spaghetti sauces Soups Thai dishes Vegetable fats & oils Pesto Arachnis oil Bouillon/Worcestershire sauce Nougat Muesli Hydrolyzed vegetable protein Chocolates Nutmeg Vegetarian dishes Animal and bird feeds Lotions, shampoos & creams Promethium (progesterone cream derived from peanuts) The only proven treatment for peanut allergy is avoidance. Omitting peanuts from the diet has no adverse nutritional consequences. Children should bring their own peanut free food with them to school and they should also be encouraged not to swap food. In common eating and food preparation areas, where there are children with severe peanut allergy, particularly in day care centers and pre-schools, all nut-containing foods should be avoided. Anaphylaxis Action Plans are important for many people with nut allergies, as most people will have an accidental exposure every couple of years. The difficulties of avoiding peanuts completely make it essential to make plans in case of a severe reaction. Your doctor will make an action plan for you and also determine whether or not you should have an Epipen (or EpiPen Junior for children) in case of a severe reaction. It is also a good idea to ask your doctor about whether you should wear a Medic-Alert bracelet to tell other people about your allergy if you become unwell.

References

1. ASCIA patient information bulletin. Peanut and tree nut allergy. Australasian Society for Clinical Immunology and Allergy. 2000. Available at: http://www.allergy.org.au/aer/infobulletins/peanut_allergy.htm
2. James, J. Food Allergies. eMedicine. 2004. Available at: http://www.emedicine.com/med/topic806.htm
3. Patient information sheet. Peanut allergy. RPA Allergy unit. 2002. Available at: www.cs.nsw.gov.au/rpa/Allergy/ resources/allergy/peanutallergy.pdf
4. Prescott, S. Tang, M. The Australasian Society of Clinical Immunology and Allergy position statement: summary of allergy prevention in children. MJA. 2005; 182: 464-7.
5. Rangaraj, S. Ramanathan, V. Tuthill, D. et al. General paediatricians and the case of resolving peanut allergy. Pediatr Allergy Immunol. 2004; 15: 449-53.
6. Warrell, D. Cox, T. Firth, J. Benz, E. Oxford Textbook of Medicine. 4th ed. 2003. Oxford University Press. Oxford.