Clinical background:
Serum tryptase is raised acutely in anaphylaxis. It is particularly useful in anaesthetic allergy where it may help in the differential diagnosis of the acute reaction. However, normal levels do not exclude allergy as a cause of a reaction.
Specimen container paediatric:
Serum-Plain tube
Specimen container adult:
Serum-SST
Minimum volume paediatric:
1 ml
Minimum volume adult:
1 ml
Availability:
Tryptase samples are tested twice a week, usually on Tuesday and Thursday.
Freq analysis:
Twice Weekly
Add on test:
All urgent add ons via telephone on 0191 282 1890 and must be confirmed via email to
Quality assurance:
UK NEQAS for Tryptase
Interpretation:
The three samples taken give information about levels of Tryptase immediately post reaction, during recovery and once a resting level has returned. It is therefore very important that all samples are taken, labelled accurately and sent to the laboratory quickly.
Reference ranges:
Normal Range: 2 – 14 ug/L
Other info:
Serum should be taken as soon as possible after the reaction (within 1 hour), a short time after the reaction (between 1 and 4 hours), as well as 24 hours later and labelled with the time of reaction and time of sample post reaction. The two samples taken give information about levels of Tryptase immediately post reaction and also once a resting level has returned. It is therefore very important that BOTH samples are taken, labelled accurately and sent to the laboratory quickly.