Estimating the within‐subject (CVI) and between‐subject (CVG) biological variation of serum tryptase. Issue 4 (13th December 2021)

• Record Type: Journal Article
• Authors: Skarbø, Birthe R.; Vinnes, Erik W.; Wentzel‐Larsen, Tore; Sylte, Marit S.; Apelseth, Torunn O.
• Is Part Of: Immunity, inflammation and disease. Volume 10:Issue 4(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-13
• Subjects: biological variation -- reference change value -- tryptase; Immunology -- Periodicals; Immunity -- Periodicals; Inflammation -- Periodicals; 616.079
• DOI: 10.1002/iid3.578
• Languages: English
• ISSNs: 2050-4527

Abstract

Abstract: Background: Tryptase is used as a biomarker to support the diagnosis of anaphylaxis and hematologic diseases. In the event of a mast cell activation during anaphylaxis, a temporary increase in the concentration of tryptase may be seen. On the basis of clinical studies, an increase of 2 µg/L + 20% from basis level has been proposed as significant. To evaluate the increase in tryptase levels, the within‐subject (CVI ) and between‐subject (CVG ) biological variations should be known. This study was conducted to estimate the biological variation of tryptase and to identify the reference change value (RCV). Methods: Blood samples were collected from healthy volunteers once a week consecutively over a 10‐week period. Tryptase was measured by the use of a fluoroenzyme immunoassay (ImmunoCAP TM ; Thermo Fisher Scientific), and linear mixed‐effects models were used to calculate the biological variation and RCV for both nontransformed and log‐transformed tryptase. Results: Fourteen presumably healthy young adults (six males and eight females, age 23–35 years) were included. The CVI was 5.6% and the CVG was 31.5% (nontransformed data). Log‐transformed data showed similar results. The analytical variation (CVA ) was 6.3% and the RCV was 23.5%. Conclusions: Young healthy adults without ongoing allergic reactions show low within‐subject biological variation. Higher biological variation was observed between subjects. Abstract : To evaluate an increase in tryptase levels in anaphylaxis, the within‐subject (CVI ) and between‐subject (CVG ) biological variations should be known. This study was conducted to estimate the biological variation of tryptase and to identify the reference change value.