Tryptase is an enzyme released along with histamine and other chemicals when mast cells are activated. This activation can occur as part of both normal immune responses and allergic (hypersensitivity) reactions, especially severe systemic allergic reactions like anaphylaxis.
The tryptase test measures tryptase levels in the blood and is used to aid in the diagnosis of anaphylaxis. Anaphylaxis is primarily diagnosed based on clinical findings due to its life-threatening nature. Currently, there is no single specific biological marker that can definitively diagnose anaphylaxis alone; however, tryptase level measurement can contribute to diagnostic support in suspected cases.
For accurate interpretation of the test, it is essential to compare a blood sample taken between 60-90 minutes after the onset of anaphylaxis symptoms with a basal (reference) blood sample taken 24-48 hours after symptoms have completely resolved.