Cristoforo Incorvaia and Nicola Fuiano
The diagnosis of allergy is mainly based on the combination of clinical history data and results of skin prick tests (SPT) or in vitro IgE tests, including specific IgE measurement, and, as third level testing, challenges with the suspected allergens. The atopy patch test (APT) that assesses the type 4, delayed hypersensitivity, is insufficiently used. We review the data obtained in recent studies on the diagnostic utility of the APT in patients with AR, especially when house dust mites are the cause of allergy.