Related Experiment Video
Updated: Jul 16, 2026
10:31
Antigenic Liposomes for Generation of Disease-specific Antibodies
Published on: October 25, 2018
Hazelnut allergy: a double-blind, placebo-controlled food challenge multicenter study
C Ortolani1, B K Ballmer-Weber, K S Hansen
1U.O. Medicina Generale 1, A.O Niguarda Hospital, Milan, Italy.
The Journal of Allergy and Clinical Immunology
|March 17, 2000
Summary
Real hazelnut allergy is confirmed by double-blind, placebo-controlled food challenges (DBPCFC). While skin and IgE tests show high sensitivity for hazelnut allergy, their low specificity means they cannot solely validate a diagnosis.
Area of Science:
- Allergy and Immunology
- Clinical Nutrition
- Food Science
Background:
- Tree nuts, particularly hazelnuts, are frequent causes of food allergy in Europe.
- Limited research exists on confirmed hazelnut allergy in individuals with suspected hypersensitivity.
Purpose of the Study:
- To identify individuals with a history of allergic reactions to hazelnut ingestion.
- To ascertain the prevalence of true hazelnut allergy using double-blind, placebo-controlled food challenges (DBPCFC).
Main Methods:
- Recruited 86 subjects reporting hazelnut ingestion symptoms across three European allergy centers.
- Performed skin prick tests (SPTs) for aeroallergens and hazelnut, alongside specific hazelnut IgE level determination.
- Utilized DBPCFC as the gold standard for diagnosing clinically relevant food allergy.
Main Results:
- DBPCFC confirmed hazelnut allergy in 77.9% of subjects (67 out of 86).
- Skin tests and IgE levels exhibited high sensitivity and positive predictive value (PPV) but critically low specificity and negative predictive value (NPV).
- Specific IgE sensitivity: 0.75, PPV: 0.92, Specificity: 0.16. SPTs (natural food) sensitivity: 0.88, PPV: 0.94, Specificity: 0.27.
Conclusions:
- Hazelnut is a confirmed allergenic food, with DBPCFC validating real food allergy.
- Diagnostic accuracy of skin prick tests and specific IgE for hazelnut allergy is limited by low specificity and NPV.
- These tests should not be relied upon exclusively for validating a hazelnut food allergy diagnosis.
Related Concept Videos
02:06Allergic Reactions
Overview
01:27Allergic Drug Reactions
Allergic reactions related to drugs are hypersensitivity responses driven by the immune system and bear no connection to the drug's therapeutic action. While drugs in isolation do not trigger an immune response, they can interact with endogenous proteins to form antigens. These antigens stimulate lymphocytes to produce antibodies. IgE-type antibodies attach themselves to mast cells. Upon subsequent exposure to the same stimulus, the antigen-antibody interaction is initiated, unleashing numerous...
01:30Allergic Reactions: Anaphylaxis
Anaphylaxis is a severe, life-threatening hypersensitivity reaction mediated by Immunoglobulin E (IgE) antibodies. When IgE binds to allergens, it triggers the release of mediators– histamine, leukotrienes, and prostaglandins from mast cells and basophils. These mediators cause vasodilation, edema, and inflammation, leading to various symptoms.The primary allergens causing anaphylaxis include food items (e.g., peanuts, shellfish), drugs (e.g., penicillin, asparaginase, corticotropin, heparin),...