Tryptase

Alternative names, keywords

Samples required

Clotted blood (gold cap, 5 mL tube). Smaller tubes are available for paediatric samples.

3 samples requested in suspected anaphylaxis:

     1. as soon as possible after first symptoms

     2. Ideally within 1 to 2 hours of onset of symptoms, and no more than 4 hours after onset of symptoms.

     3. A baseline sample should be taken 24 hours or more after the event. A form may be provided for later sampling if the patient is not admitted.

Samples and request forms must be clearly labelled with dates and times. Clinical information regarding onset of symptoms is essential for interpretation.

Test indications

Evaluation of mastocytosis or suspected anaphylaxis. The test has best sensitivity in the investigation of reactions to drugs and insect venoms particularly in children. It also has value in "idiopathic" (untriggered) anaphylaxis.

Reference range

0.0 - 11.0 µg/L

Tryptase is chronically raised in mastocytosis. In anaphylaxis, tryptase will be increased during the reaction, then return to baseline.

Turnaround time

Referral lab quotes turnaround time of 6 days, however additional time must be allowed for packing, dispatch and delivery of sample, and return and processing of results.

Enquiries

Immunology (Referrals)