IgE Tests for Food Allergies

Food allergies are usually classical early allergic reactions, but the reaction may follow a variety of courses. The range of reactions triggered by food allergens includes local acute symptoms in the gastrointestinal tract, such as vomiting, nausea, diarrhoea, gastrointestinal pain, constipation and flatulence, all the way through to cutaneous reactions (e.g. urticaria, worsening eczema in patients with atopic dermatitis), even including severe systemic reactions, such as lethal anaphylactic shock. Allergies to cows milk, chicken eggs, peanuts, wheat and soya are predominant in childhood, while allergies to nuts, fish, soya, wheat, celery and seafood are most frequently observed in adults. Secondary food allergies (oral allergy syndrome as a result of cross-reactivity) may be triggered after sensitisation to a typical inhaled allergen (e.g. pollen allergy). If the medical history leads to a suspicion of an IgE-mediated immediate-type allergy, evidence of sensitisation, obtained by measuring serum sIgE antibodies, is indicated. 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. In vitro basophilic activation tests may provide information on the clinical relevance of a positive IgE test result.