The atopy patch test: is it time to redefine its significance?

Based on the pathophysiology of AEDS, in which the mechanisms of delayed hypersensitivity are predominant, the APT seems to have a greater significance than skin prick tests or in vitro IgE tests in patients with current or past history of AEDS. That different sensitization mechanisms underlie these different clinical expressions seems conceivable. In particular, if mite allergens enter the skin in the presence of a filaggrin-dependent skin barrier dysfunction, the sensitization mechanism seems to be ultimately revealed by a positive APT.