Allergen Testing: Purpose, Procedure, Interpretation

Allergic diseases exert a significant global burden impact individuals across all age groups. Allergies to food, aeroallergens, drugs, and venom complicate patients’ lives and, at sometimes pose life-threatening risks. Skin prick/puncture tests, intradermal tests, and patch tests are skin tests that have been utilized to diagnose allergic diseases. The skin prick test (SPT) typically induces a wheal and flare reaction, indicative of Type 1 hypersensitivity. In intradermal skin testing, allergen extracts are administered into the dermis at a concentration that is 100–1000 times less than that used in SPT. Patch tests are typically used for patients experiencing delayed-type hypersensitivity reactions. Nevertheless, conducting skin tests and accurately interpreting the results need adequate training and also involve the possibility of unexpected systemic responses. Serum-specific IgE (sIgE) measurement, as a complementary or alternative diagnostic tool, is widespread. Component-resolved diagnosis might be beneficial in cases where polysensitization complicates the diagnosis, or when negative skin prick test (SPT) findings are obtained despite a potential history of allergy. The allergen provocation test could be used as a gold standard method in particular patients.