What is this test?
Tryptase is an enzyme that is contained in mast cells and can be temporarily increased when they are highly activated, for example in anaphylaxis.
Why might it be ordered?
- For additional evaluation after a suspected severe systemic allergic reaction.
- For baseline evaluation in suspected disease with increased mast cell count or activity.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Collection time in relation to the reaction matters. After an acute reaction, your clinician may request an early sample and a later baseline sample. Never delay emergency treatment to have this test. Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
An increase from personal baseline may support mast cell activation. A persistently elevated baseline has a variety of possible causes. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.