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Updated: Jun 22, 2026
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Trans-vivo Delayed Type Hypersensitivity Assay for Antigen Specific Regulation
Published on: May 2, 2013
Skin testing in delayed reactions to drugs
1Department of Dermatology, Fournier Hospital, University Hospital of Nancy, Nancy, France. a.barbaud@chu-nancy.fr
Immunology and Allergy Clinics of North America
|July 1, 2009
Summary
Drug skin tests, including patch and prick tests, help diagnose cutaneous adverse drug reactions (CADR). These tests are valuable for maculopapular rash, with a negative predictive value around 90%.
Area of Science:
- Dermatology
- Allergology
- Clinical Immunology
Background:
- Cutaneous adverse drug reactions (CADR) are common, with delayed hypersensitivity reactions posing diagnostic challenges.
- Drug skin tests are crucial for identifying specific drug culprits in CADR.
Purpose of the Study:
- To evaluate the utility of various drug skin tests in diagnosing CADR.
- To detail the application of patch testing in patients with different drug-induced skin reactions.
Main Methods:
- Review of drug skin testing modalities, including patch tests, prick tests (with delayed readings), and intradermal tests (IDT) with immediate and delayed readings.
- Focus on the diagnostic approach for maculopapular rash (MPR).
Main Results:
- Drug skin tests are valuable for CADR, particularly MPR, with patch tests being the initial step.
- Prick tests and IDT (with delayed readings) are used sequentially if initial tests are negative or if injectable forms are available.
- Drug skin tests aid in assessing cross-reactivity between drugs and have a negative predictive value of approximately 90%.
Conclusions:
- Drug skin tests, especially patch tests, are effective tools for investigating CADR.
- The diagnostic yield depends on clinical presentation and the specific drug, with a high negative predictive value supporting their use.
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