A multi-center, retrospective review of patch testing for contact dermatitis in allergy practices.

Background: Studies assessing patch testing (PT) in allergy practices are limited.

Objectives: To determine whether PT results using a limited panel of allergens such as in the Thin-Layer Rapid-Use Epicutaneous Test (TT) as compared with an expanded panel, such as the addition of supplemental allergens (North American Contact Dermatitis [NACD] Panel, Dormer Cosmetics, hairdressing series, corticosteroid series, and personal products) will miss a significant number of positive PTs. To compare our PT results with published data from dermatology practices.