Peanut allergy

From Wikipedia, the free encyclopedia

Peanut allergy
Classification and external resources
ICD-10 T78.4
ICD-9 V15.01
DiseasesDB 29154

Peanut allergy is a type of food allergy, distinct from nut allergies. It is a hypersensitivity to dietary substances from peanuts causing an overreaction of the immune system which may lead to severe physical symptoms for millions of people[1]. The Asthma and Allergy Foundation of America estimates that peanut allergy is the most common cause of food-related death.[2]. Prevalence among adults and children is similar — around 1% — but at least one study shows it to be on the rise in children.[3] 25% of children with a peanut allergy outgrow it.[4] It is usually treated with an exclusion diet and vigilant avoidance of foods that may be contaminated with whole peanuts or peanut particles and/or oils. The most severe peanut allergies can result in anaphylaxis[5], an emergency situation requiring immediate attention and treatment with epinephrine.

Contents

[edit] Symptoms

Symptoms of peanut allergy are related to the action of Immunoglobulin E (IgE) and other anaphylatoxins, which act to release histamine and other mediator substances from mast cells (degranulation). In addition to other effects, histamine induces vasodilation of arterioles and constriction of bronchioles in the lungs, also known as bronchospasm (constriction of the airways).

Symptoms can include the following:[6]

The British Dietetic Association warns that: "If untreated, anaphylactic shock can result in death due to obstruction of the upper or lower airway (bronchospasm) or hypotension and heart failure. This happens within minutes to hours of eating the peanuts. The first symptoms may include sneezing and a tingling sensation on the lips, tongue and throat followed by pallor, feeling unwell, warm and light headed. Severe reactions may return after an apparent resolution of 1-6 hours. Asthmatics with peanut sensitivity are more likely to develop life threatening reactions."[6]


As with most allergies, avoidance is the key. All labels for foods, medicines, cosmetics, creams, and ointments should be read. A history of allergic reactions after consuming a peanut may suggest an allergy.

While several companies have developed promising drugs to counteract peanut allergies, trials have been mired in legal battles.[7]

[edit] Treatments

Food allergy experts at the Duke University Medical Center believe that an immunotherapy treatment for peanut allergies will be available to affected people within 5 years. [8] Immunotherapy would be used to treat a person's immune response to peanuts from an allergic reaction to a nonallergic response. This is great news for the parents of affected children and adults living with the allergy. The condition is actually becoming more common affecting about 1% of children in total. The number of affected people doubled between 1997 and 2002.[9]

[edit] Deaths from peanut allergy

Approximately 125 people die in the United States each year from food allergies.[10][11] It was reported on Leanord Lopate Show that the CDC figures for food allergy deaths in 2007 were in a much lower range (12-20)[12]

The dangers of peanut allergy are real, even if sometimes misrepresented in the popular press. The 2005 death of Christina Desforges, which was initially reported as a result of exposure to peanuts, spurred many parents to speak out about the dangers from such seemingly mundane matters as peanut butter and jam sandwiches at schools or peanut shells on the floors of restaurants.[13] According to a coroner's statement in March 2006 however, Ms. Desforges did not die of anaphylactic shock caused by a kiss from her boyfriend after he ate a peanut butter snack, but in fact died as a result of asthma-linked respiratory failure, which was triggered by tobacco smoke at a party. Research by Jennifer Maloney suggests that peanut allergens normally leave the saliva after about an hour.[1]

[edit] Allergen-Free Peanuts

On July 20, 2007, the North Carolina Agricultural & Technical State University announced that one of its scientists, Dr. Mohamed Ahmedna, had developed a process to make allergen-free peanuts. Initial testing showed a 100 percent inactivation of peanut allergens in whole roasted kernels, and human serums from severely allergic individuals showed no reaction when exposed to the processed peanuts. Food companies have expressed an interest in licensing the process, which purportedly does not degrade the taste or quality of treated peanuts, and even results in easier processing to use as an ingredient in food products.[14]

[edit] See also

[edit] External links

[edit] References

  1. ^ National Institutes of Health, NIAID Allergy Statistics 2005 http://www.niaid.nih.gov/factsheets/allergystat.htm
  2. ^ “Allergy Facts and Figures,” Asthma and Allergy Foundation of America http://www.aafa.org/display.cfm?id=9&sub=20&cont=517
  3. ^ Prevalence of peanut and tree nut allergy in the United States determined by means of a random digit dial telephone survey: A 5-year follow-up study http://www.allerg.qc.ca/peanutallergy.htm#pressreldec903
  4. ^ Great Ormond Street Hospital for Children NHS Trust and UCL Institute of Child Health, Peanut Allergy - Family Factsheet http://www.ich.ucl.ac.uk/factsheets/families/F000279/
  5. ^ National Report of the Expert Panel on Food Allergy Research, NIH-NIAID 2003 http://www3.niaid.nih.gov/about/organization/dait/PDF/june30_2003.pdf
  6. ^ a b The British Dietetic Association. Peanut Allergy Information for Dietitians. 1999 http://www.bda.uk.com/Downloads/peanutallergy.pdf
  7. ^ highbeam.com
  8. ^ Expert sees peanut allergy solution within 5 years - Yahoo! News
  9. ^ Expert sees peanut allergy solution within 5 years - Yahoo! News
  10. ^ Burks, Peanut-induced anaphylactic reactions http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=10436387&dopt=Abstract, Int Arch Allergy Immunol, 07-1999.
  11. ^ John Weisnagel, Peanut allergy: where do we stand? http://www.allerg.qc.ca/peanutallergy.htm, Association of Allergists and Immunologists of Quebec, 05-27-2007.
  12. ^ wnyc.org, {{{title}}}, [[{{{publisher}}}]], [[{{{date}}}]].
  13. ^ "Nutty killer: Peanut policy perplexes parents", Hook weekly, 2006-01-05. Retrieved on 2006-12-13. 
  14. ^ North Carolina A & T State University Press Release, July 23, 2007