Establishing reference intervals for soluble urokinase plasminogen activator receptor in Northern European adults

Objectives

Soluble urokinase plasminogen activator receptor (suPAR) may have untapped potential in clinical diagnostics. Previous studies determined reference intervals using an enzyme-linked immunoassay, but there is a need for reference intervals using a faster assay if the analysis is to be used in emergency medicine. The current study aims to determine reference intervals for suPAR using a fully automated particle-enhanced turbidimetric immunoassay (PETIA) according to the Clinical and Laboratory Standards Institute guideline A28-A3c.

Design and methods

Blood samples were prospectively collected from Danish blood donors. Plasma suPAR was analyzed on the cobas 8000 module c502 in an open channel using a PETIA. Sex-partitioned reference intervals were determined using a parametric quantile approach.

Results

The study included 241 participants—123 females and 118 males. The common reference interval for suPAR was 1.56–4.11 ng/mL (95% confidence intervals (CI) for the lower and upper limits were 1.56–1.63 and 3.81–4.47, respectively). The reference interval for females was 1.59–4.65 ng/mL (95% CIs 1.48–1.70 and 4.09–5.48, respectively) and for males, 1.56–3.59 ng/mL (95% CIs 1.47–1.65 and 3.31–3.93, respectively).

Conclusions

Our results support using sex-partitioned reference intervals for suPAR and provide a basis for future studies using the PETIA method.