Résumé
Drug hypersensitivity, including the allergic type, is one of the side effects of drugs and is a daily worry for the clinician. Even though urticarial and maculopapular eruptions are the most frequent manifestations, there are many clinical forms, mirroring many distinct pathophysiological events. The diagnosis of drug hypersensitivity often relies on clinical histories, skin tests, patch tests, and a few validated in vitro tests, such as serum specific IgE assays, which are available only for a few drugs. The sensitivity of these tests is not 100%; in selected cases, therefore, provocation tests are necessary. However, new diagnostic tools, such as the basophil activation test and the lymphocyte activation test, have been developed and are under validation. Their routine use could increase the sensitivity of diagnostic work-ups, thus reducing the need for drug provocation tests.
Most of these diagnostic tools have been carefully evaluated by the European Network of Drug Allergy (the European Academy of Allergology and Clinical Immunology drug hypersensitivity interest group). When properly performed in specialised centres, a firm diagnosis is often possible and safe alternative medication can be proposed.