D3.49 - Clinical significance and safety of provocation test for drug allergy diagnosis in outpatient unit: A real world observational study

Drug allergy is one type of drug adverse reaction that is immunologically mediated and triggered by exposure to a drug, which is a very common problem confronted in clinical work, and brings difficulties for the administration of drugs. Drug provocation test (DPT) is considered as the golden standard to diagnose the type I hyerresponsive allergy of drugs. However, it is at the very initial stage in China with the consideration of risk, clinical experience is in the utmet needs. We have developed the drug provocation test at the outpatient unit since August, 2017. Hereby we shared our experience of our clinical application of drug provocation test at outpatient site aim to provide solid data of provocation test and helpful experience for the related clinicians.   

This is an observational study on patients of suspected drug allergy from August 2017 to April 2024. General information and data of serum antibodies was collected. The drug provocation tests were conducted in a outpatient clinic room equipped with emergency rescue equipment.

A total of 56 subjects were enrolled in this study with 75 instances of suspected drug allergies, involving 22 different suspected allergenic drugs. The tested drugs primarily consisted of anesthetics and antibiotics. 156 drug provocation tests were conducted 12 underwent single drug provocation test including 5 with antibiotics, 6 with lidocaine, 1 with articaine hydrochloride and epinephrine tartrate. The remaining 44 patients underwent provocation tests with multiple drugs simultaneously including 13 with multiple antibiotics, 28 with multiple anesthetics, and 3 with multiple antibotics and anesthetics. 23 patients achieved positive results while 33 patients were negative, resulting in a positive rate of 41% (23/56). The positive rate of patients with single system reaction is 41%(12/29) , while it is 25% (1/4) in patients with multiple system reaction, and 43%(10/23) in patients with anaphylaxis.32 tests were positive with the positive rate of 20%, 1 tests suspected positive. For 31 subjects who underwent 48 provocation tests to determine if the suspected allergenic drug was truly allergenic, The consistency for anesthetics was notably lower. The severity of drug allergy, personal history of allergic diseases, total IgE, sIgE, and eosinophils were not found to be influencing factors for the drug provocation test results. No severe adverse reactions were observed.

 Drug provocation tests can provide safe and effective drug treatment options for patients, especially for the use of antibiotics and anesthetics. Conducting drug provocation tests in an outpatient setting is both safe and effective.