Hazelnut

Hazelnut is one of the most common food allergens and may cause allergic reactions of varying severity in both children and adults. Allergy develops when the immune system overreacts to proteins found in hazelnuts.

This test measures hazelnut-specific IgE antibodies and helps confirm allergic sensitization. The results assist in establishing the relationship between symptoms and hazelnut consumption, assessing the risk of allergic reactions, and guiding further diagnosis and management.

Indications

The test is recommended for individuals with:

• skin redness, itching, or swelling after eating hazelnuts;
• hives (urticaria);
• itching or swelling of the lips, tongue, mouth, or throat;
• nasal congestion, sneezing, or watery eyes after exposure to the allergen;
• abdominal pain, nausea, vomiting, or diarrhea after eating hazelnuts;
• cough, wheezing, or difficulty breathing;
• suspected food allergy;
• the need to identify the cause of allergic reactions;
• follow-up of patients with a confirmed tree nut allergy.

How does the allergic reaction develop?

In individuals with an allergy, the immune system mistakenly recognizes hazelnut proteins as harmful. In response, it produces specific IgE antibodies, which bind to mast cells and basophils.

Upon subsequent exposure to the allergen, these cells release biologically active substances, primarily histamine, leading to symptoms such as itching, skin rash, swelling, runny nose, digestive symptoms, or breathing difficulties.

Measuring hazelnut-specific IgE helps confirm IgE-mediated allergic sensitization and assess the likelihood of allergic reactions upon exposure to this allergen.

Procedure

The test is performed using a venous blood sample.

The sample is analyzed in the laboratory to detect hazelnut-specific IgE antibodies. The test is safe because it does not require direct exposure to the allergen, making it suitable even for patients at increased risk of severe allergic reactions.