Clin Chem Lab Med. 2026 Mar 12. doi: 10.1515/cclm-2025-1169. Online ahead of print.
ABSTRACT
OBJECTIVES: Accurate measurement of 17α-hydroxyprogesterone (17-OHP) in human serum and plasma is required for steroid profiling, to ensure the appropriate diagnosis of congenital adrenal hyperplasia. Therefore, an isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS)-based candidate reference measurement procedure (RMP) to quantify 17-OHP in human serum and plasma has been developed.
METHODS: A two-dimensional heart-cut LC approach was used to minimize matrix effects and prevent co-elution of interferences. A post-column infusion experiment was conducted to assess the potential impact of different matrices on ion suppression or enhancement effects. A multi-day validation experiment assessed precision, trueness and accuracy. Measurement uncertainty was evaluated in compliance with current guidelines.
RESULTS: The working range of this RMP was 0.0200-60.0 ng/mL (0.0605-182 nmol/L) and the method proved to be matrix-independent. The intermediate precision coefficient of variation (CV) ranged from 1.5 % to 2.1 % and repeatability CV from 1.3 % to 1.9 %, across all concentration levels. The relative mean bias ranged from -4.0 % to 2.0 %, regardless of the matrix and concentration level. The measurement process for single measurements showed an expanded uncertainty (k=2) between 3.6 % and 4.5 %. This uncertainty was further reduced performing the target value assignment (n=6), resulting in a range of 2.0-2.5 %. Equivalence between the candidate RMP and the Joint Committee on Traceability in Laboratory Medicine-listed RMPs was established through participation in the External Quality Assessment scheme for reference Laboratories in Laboratory Medicine (RELA) ring trial.
CONCLUSIONS: The performance of this procedure enables the evaluation and standardization of routine assays, and the evaluation of patient samples, to ensure traceability of individual patient results.
PMID:41808365 | DOI:10.1515/cclm-2025-1169