Tryptase Genotyping for Diagnosis of Mast Cell Disorders: consder the test if serum tryptase level exceeds 6.5 ng/mL

Tryptase levels in serum can be used for diagnosis and management of:

- clonal mast cell disorders such as mastocytosis
- severe mast cell–dependent systemic reactions such as anaphylaxis

Hereditary α-tryptasemia (HαT)

The majority of individuals with elevated basal serum tryptase levels have increased TPSAB1 gene encoding α-tryptase. This defines hereditary α-tryptasemia (HαT). HaT affects nearly 6% of the general population.

When to check for TPSAB1 gene?

The presence or absence of HαT should be determined when defining what is an abnormal serum tryptase level.

Symptomatic individuals undergoing evaluation for a mast cell–associated disorder with a baseline serum tryptase level exceeding 6.5 ng/mL should be considered for tryptase genotyping in order to screen for HαT.

More in the JACI-IP article below:
https://www.jaci-inpractice.org/article/S2213-2198(22)00489-5/fulltext