Atopy Patch Testing with Aeroallergens and Food Proteins

Atopy patch test (APT) is an experimental epicutaneous test method to diagnose aeroallergen - or respectively food allergentriggered atopic eczema. Application of aeroallergens or foods may promote allergenspecific T-cell responses and IgE-mediated immune responses at the same time. Positive APT reactions are associated with an increased specific serum IgE, positive skin prick test reaction, allergen exposure in history, long eczema duration, or rhinoconjunctivitis. APT may be indicated in patients with eczema with suspicion of aeroallergen symptoms without proof of positive specific IgE and/or a positive skin prick test and in patientswith severe and/or persistent atopic eczema with unknown trigger factors or multiple IgE sensitizations without proven clinical relevance. However, to this point, despite extensive efforts at APT standardization, no licensed test substances are available for routine use today.