In vitro testing for hypersensitivity-mediated adverse drug reactions: Challenges and future directions

Drug hypersensitivity reactions (DHRs) are uncommon but potentially fatal adverse events. Their diagnosis and prediction are difficult given their variable presentation and the overlap of symptoms with those of other clinical conditions. Systemic rechallenge is considered the gold standard for the diagnosis of DHRs; however, this may have severe consequences. In vitro tests are currently not sufficiently reliable to provide the basis for clinical decisions. This article summarizes the challenges associated with in vitro testing for DHRs.