Peanut allergy.Peanut oil allergy.Peanut allergy treatment.Peanut butter allergy.

What are the symptoms of peanut allergy?

redness and swelling; itching and tingling in and around the mouth and throat; gastrointestinal symptoms such as diarrhea, stomach cramps, nausea, and vomiting; swollen throat, shortness of breath or wheezing, and a runny nose. In severe cases, anaphylaxis (one of the most common causes of food-induced anaphylaxis) occurs.

*Anaphylaxis is an allergic symptom that appears in the whole body in a very short time after touching, eating (drinking), or inhaling an allergy-causing substance. It is a life-threatening reaction.

Shock incidence by causative food: peanuts ranked fifth with 15.4%. Peanuts have been shown to cause more fatal reactions than other foods in small doses. (1g of peanuts, 10g of other food)

How many people have peanut allergies?

Peanut allergies are on the rise in children. A 2017 US study found that peanut allergies in children have increased 21% since 2010, and nearly 2.5% of American children may have a peanut allergy. In Japan, it ranks eighth with around 3% of immediate food allergies. Peanut allergy is rare in children in developing countries where peanut products have been used to alleviate malnutrition, even a small amount can cause anaphylaxis, so caution is required. Peanuts are legumes (like soybeans) and not nuts.

What are some precautions you can take to prevent this?

People with peanut allergies should avoid the following foods:

Peanuts (groundnuts), peanut butter, peanut flour, mixed nuts, peanut-containing (sweets, chocolate, crackers, ice cream), etc.

Asian and Mexican cuisines where peanuts are commonly used, including ethnic cuisines.

The 7 specified raw materials are allergens that must be labeled in processed foods that are packaged in containers and are 7 items: eggs, milk, wheat, shrimp, crab, peanuts, and buckwheat.　

Direct contact with peanuts, use of skin care products containing peanuts, and inhalation of processed peanut powders, such as peanut flour, and dusty and aerosols containing peanuts have been reported to cause allergic reactions. Peanuts are sometimes used in sweets such as curry roux and chocolate, and in dressings. It is difficult to judge whether or not a product is used just by looking at it.

 As a result, these products and others may cause allergies.

Allergens (substances that trigger allergic reactions) are strengthened by heat-treating peanuts.

Juices and dressings containing kiwis, apples, and citrus fruits may cause cross-allergenicity and should be used with caution. *Cross-reactivity refers to binding to similar antigens other than the antigen from which the antibody was created.

What is pollen food allergy syndrome?

Immediately after eating vegetables and fruits, people with hay fever experience irritation and itching in the oral cavity, pharynx, and lip mucosa within a few minutes. Get better. Gastrointestinal symptoms such as nausea, diarrhea, and abdominal pain, hay fever symptoms such as a runny nose and itchy eyes may occur, and in rare cases, serious systemic symptoms such as swollen throat, shortness of breath, hives, and anaphylactic shock may occur. I have.

In the case of peanuts, the most common possible causes are birch tree pollen, such as alder and birch. Betulaceae pollen scatters at the same time as cedar and cypress. Betulaceae pollen may also react to rose fruits such as peaches.

How do you diagnose peanut allergy?

 A small amount of food is applied to the skin and pricked with a needle. If you are allergic to certain substances, your skin will react.

Blood tests: By checking the amount of allergen-type antibodies in the bloodstream called immunoglobulin E (IgE) antibodies, the immune system's response to certain foods can be measured. The diagnostic ability of Ara h2 is high, and a high value (score of 4 or more) is diagnosed as a peanut allergy.

Challenge test: In addition to sensitization to peanuts, diagnosis is made by a history of frank immediate-type allergy or provocation by an oral food challenge test (challenge test). Stress testing carries a considerable risk of causing serious allergic reactions. Low or negative Ara h2 and specific IgE (peanut) are positive and should be confirmed with a challenge test.

How do you treat peanut allergy?

・Antiallergic drugs 

・Tracheodilators

・Injection, inhalation, or oral administration of steroids, etc.

 Inject adrenaline when anaphylaxis occurs. 

so that they can inject themselves with a therapeutic drug (adrenaline) when an anaphylactic reaction occurs in daily life. 

After the symptoms of anaphylaxis have subsided, a second anaphylaxis may occur again several hours later without contact with the allergen, and this is called a biphasic anaphylactic reaction. In a 2015 study in the United States, 2% of people treated for peanut allergy in a hospital emergency room had this biphasic reaction (second slowest reaction). The delayed response occurred on average 15 hours after people were first treated. Another study found that about 15% of children had a second severe allergic reaction hours after the first.

Peanuts are often thought of as nuts, but they belong to the same legume family as soybeans.

However, there is almost no allergic complication with closely related soybeans, and rather with other types of nuts, allergy complication occurs at a high rate.

In Europe and the United States, peanut butter is often consumed during the weaning period, so the frequency is high,
Onset is due to ingestion by pregnant or breastfeeding mothers during infancy, ingestion of peanut butter by the individual in the West, percutaneous sensitization of skin care products containing peanuts, and contaminants of mites and household dust in processed peanut powder. It is believed to be caused by airway sensitization.

Recently, the incidence of oral allergy due to common antigens of birch pollen has been increasing.
In addition, not only the fruit but also the shell is antigenic.

In the diagnosis, Areh 1 to 3 are the main allergens among peanut proteins, and it is said that anaphylaxis is likely to occur when these IgE antibodies are high. Recently, it has become possible to test for IgE antibodies against Arah2, which is useful for predicting the onset of anaphylaxis. Tolerance to peanuts is said to be difficult to develop, but some mild cases of infant onset may develop tolerance. However, even if the initial symptoms are mild, it is said that 50% will become severe.
In addition to the immediate reaction, there is more common antigenicity with birch pollen than with peanuts.

The test measures IgE antibodies in walnuts, cashews, hazelnuts, cacao, brazil nuts, almonds, coconuts, and components of walnuts and cashews.

Cross-reactivity with peanuts is said to be 35%, and cross-reactivity with nuts is said to be 50%, so we will conduct regular inspections and confirm with food challenge tests as necessary.