Establishing of reference value and estimate of biological variation for the allergy analyte tryptase

This project was performed on behalf of the laboratory section for allergy- and protein analysis at the laboratory for clinical chemistry (LKB), Haukeland Universitetssjukehus (HUS). The aim of this project was to establish reference values for tryptase in a healthy population with or without allergies, and to evaluate the biological variation for tryptase. The project was approved by the regional ethical committee (2017/1179/REK Vest). Samples were collected from healthy volunteers with and without allergies (n=245). The samples were analysed at Pahdia 1000 (ImmunoDiagnostics, Thermo Fisher Scientific, Uppsala, Sweden). The reference values and the associated 90 % confidence intervals were calculated both with the parametric and non-parametric method. It was also examined if different variables such as age, gender, allergies, exercise and medication/supplements could have an impact on the tryptase values. A pilot-project was performed to examine the biological variation for tryptase, including 14 healthy volunteers who agreed to take blood samples for 10 weeks. The samples were stored frozen, and by the end of the sample collection the samples from 5 of the volunteers were thawed and analysed. Linear mixed effects-models was used for statistical computations. The non-parametric method gave a reference value for tryptase as