Recent advances in the diagnosis of drug allergy.

The diagnosis of immunologic drug reactions is based primarily on a detailed clinical history and historical data on relative immunogenicity of the culprit drugs. Except for a few standardized skin tests, most of the other methods for diagnosing drug allergy have unproven diagnostic or predictive clinical utility. Many tests for drug-specific immune responses are suggestive if positive, but have unknown negative predictive values. The present review addresses the most recent published literature regarding the diagnosis of drug allergy. Recent advances in the use of the lymphocyte transformation test, and delayed intradermal skin tests and patch tests for the diagnosis of delayed cutaneous reactions to penicillins suggest that these tests may have clinical utility, although confirmatory reports are still missing. For the diagnosis of acute vaccine reactions, gelatin-specific IgE as measured by radioallergosorbent test has now been shown to be reliably associated with allergic reactions to gelatin-containing vaccines.