Peanut Allergy Test
Latin name: Arachis hypogaea
Source material: Shelled nuts
Family: Fabaceae (Leguminosae)
Common names: Peanut, Groundnut, Monkeynut
Peanut is a food which may result in allergy symptoms in sensitised individuals.
Peanut Allergy Test: Allergen Exposure
Peanuts are the seeds of an annual legume, which produces its fruit below the soil surface, in contrast to tree nuts like walnuts or almonds.
The peanut originated in South America as early as 5,000 years ago, and from there was spread by traders and explorers to the rest of the world. Now, peanuts are cultivated globally as a commercial crop.
Peanuts are consumed mainly as Peanut butter, as snacks (roasted, salted, plain or dry roasted), in candy and in baked goods.
Peanuts also yield widely used cooking oils (both refined and crude, aromatic and non-aromatic).
Peanut flour is an important ingredient in a variety of processed foods.
It has been known for peanuts to have been deflavoured, reflavoured and sold as walnuts, almonds, and pecan nuts.
Peanut Allergy Test: Allergen Description
A number of allergens present in peanuts have been characterised to date, including a number of seed storage proteins of the conglutin, vicilin, and glycinin families.
Furthermore, a number of uncharacterised allergens have been detected in peanut.
The allergenicity of peanut allergens has been clearly shown to be dependant on the degree of heat the substance is exposed to, and it is evident that roasting increases the allergenicity of peanuts.
Peanut allergens have been shown to cross into breast milk and may sensitise infants.
Peanut Allergy Test: Potential Cross-Reactivity
An extensive cross-reactivity among the different individual species of the Fabaceae could be expected but in fact does not occur frequently.
Although peanut shares homologous proteins with other beans and legumes, the majority of individuals with clinical reactions to a single legume do not show clinical reactions to the other legumes.
Furthermore, other legumes rarely provoke severe anaphylactic reactions or result in a lifelong allergy.
Cross-allergenicity has been demonstrated to be most marked among extracts of peanut, garden pea, chick pea, and soya bean.
Reactivity to tree nuts is a serious problem for peanut-allergic people. Peanut and tree nut allergic reactions coexist in 25-50% of peanut-allergic patients, and allergic reaction to tree nuts such as walnuts, cashews, pecans and pistachios can develop even though tree nuts are from a different botanical family.
Reactions frequently occur on first known exposure and may be life-threatening.
Peanut Allergy Test: Clinical Experience
Peanuts are a significant cause of serious food allergy in both adults and children. Unlike other food allergies, peanut allergy usually begins in childhood and persists throughout the affected individual’s lifetime.
First sensitisation has been attributed to the presence of peanut allergen in breast milk. Peanut allergy has also been reported to be transferred through liver, kidney, and bone marrow transplantation.
Peanut allergic reactions are more likely to be severe or even fatal than reactions to other food allergens.
Atopic dermatitis, angioedema, asthma, diarrhoea, nausea and vomiting, and anaphylaxis have been reported. Urticaria may be a prominent symptom. Angioedema of the lips and tongue following ingestion of peanut butter, and localised urticarial reactions following direct skin contact, have been described.
Although not reported frequently, asthma may be a significant feature in peanut allergy.
There is good evidence that peanut allergy is on the increase.