ROLE OF CLINICAL LABORATORY IN ALLERGY TESTING

The clinical laboratory has a well defined role to play in the diagnos is and management of patients with allergy. Elevated serum levels of t otal IgE and/or allergen-specific IgE indicate that an IgE mediated ev ent has occurred. Methods such as basophil degranulation and basophil or leukocyte histamine release can provide similar information. Sensit ive and precise methods suitable for automation are available for quan titation of histamine in whole blood or plasma. Methyl histamine can b e assayed in urine. Eosinophil cationic protein levels in serum can be used as an indicator of eosinophil activation in disorders such as as thma and atopic dermatitis. Similarly, serum mast cell tryptase levels can confirm or exclude an anaphylactic reaction both in life and as a cause of death. This review documents and compares commercially avail able methods for these assays and discusses their application to scree ning, diagnosis, and management of patients with allergy.