Type I Allergy

IgE-mediated type I allergy is accompanied by mild to life-threatening symptoms. Allergen-specific IgE antibodies are formed after initial contact with the allergen and bind to the cell surface of histamine-rich cells, basophilic granulocytes or mast cells. In the event of a second contact with the allergen, a massive histamine release is triggered by the bound IgE antibodies. This can lead to symptoms of a type I allergy (immediate type) within minutes of contact with the allergen. Typical symptoms are allergic conjunctivitis, allergic rhinitis, allergic asthma, laryngeal oedema, atopic dermatitis and anaphylactic shock. Foodstuffs or inhalation allergens, such as plant pollen, house dust mites, animal epithelia or animal hair are often responsible for this type of allergy. For the clarification of IgE-mediated allergies, both symptom-related and individually compiled profiles are available in laboratory diagnostics. Measurement is performed using ImmunoCAP-Technology (Phadia 1,000), which also allows molecular diagnostics (based on the components used), facilitating the determination of a more precise sensitisation profile. This also permits risk assessments (anaphylaxis), as well as statements to be made regarding potential cross-reactivity (secondary food allergy). In vitro basophilic activation tests may provide information on the clinical relevance of a positive IgE test result.