Definition – what is a hazelnut allergy?
Hazelnut allergy is an intolerance reaction of the body caused by hazelnuts. The allergy typically involves an excessive reaction of the immune system after contact with hazelnuts, which causes the allergic reaction. Hazelnut allergy is most often triggered by the consumption of hazelnuts. Many people are allergic to raw hazelnuts, but cooked or baked hazelnuts make hazelnut allergies much less common. Hazelnut allergy is an allergy of the so-called immediate type, which can lead to severe reactions up to life-threatening allergic shock.
Causes
Why an allergy develops is often still unclear. Genetics play an important role in the development of allergies. Children of allergy sufferers are often allergic to many substances themselves.
A hazelnut allergy is one of the most common allergies. It often occurs together with other allergies, for example to fruit, pollen, mites (house dust) and animals. Many allergy sufferers are also affected by atopic dermatitis (neurodermatitis).
Diagnosis
The diagnosis of hazelnut allergy is usually made at the second contact with the hazelnut. When a person comes into contact with a hazelnut for the first time, the immune system becomes sensitized to the hazelnut antigen. The second contact causes an allergic reaction with typical symptoms.
In this case, the medical history plays an important role in the diagnosis. By questioning the person concerned, it is possible to determine which substance may have caused the reaction. An allergy test can then be performed.
In blood tests, various messenger substances of the immune system can be detected, which are typically elevated in an allergic reaction. Test procedures such as the prick test are also used. This involves injecting various potential allergens under the skin. The skin is then observed for some time. In the case of an allergy, the area where the allergen was injected into the skin becomes reddened and swollen, possibly forming a wheal.
I recognize a hazelnut allergy by these symptoms
Hazelnut allergy can manifest itself in many different symptoms. The symptoms range from harmless redness of the skin and itching to life-threatening narrowing of the respiratory tract. Typically, contact with the allergen occurs first.
In the case of the hazelnut, it is usually consumed. Subsequently, symptoms appear in the mouth area. These may include itching and redness of the skin and mucous membranes.
This skin reaction can spread to the whole body in case of pronounced allergies. This is where a so-called urticaria with wheals and extensive reddening of the skin can develop. In the case of pronounced allergic reactions, swelling can occur in the mouth area and in the area of the airways.
In the worst case, this can lead to pronounced breathing difficulties. The allergic reaction to the hazelnut makes the vessel walls more permeable to liquid, the liquid leaks from the vessels into the surrounding tissue. This causes blood pressure to drop, and fluid accumulation in the skin and possibly in the lungs, which also causes breathing difficulties and oxygen deficiency.
In addition, the airways become narrower, which further increases the shortness of breath. Such a pronounced reaction is called anaphylactic shock. Further symptoms can be the tension of the muscles in the intestinal wall with abdominal pain (often cramping) with nausea and vomiting. In addition, the nose often begins to run and the eyes water, as the body is stimulated to produce more mucus in the nose and tear fluid.
