Volumetric absorptive microsampling for steroid monitoring in congenital adrenal hyperplasia: Can capillary blood measurements reliably be converted to plasma concentrations?

Authors

Hanna De Baets, Tim Reyns, Tom Fiers, Martine Cools, Christophe P Stove

Published in

Clinica chimica acta; international journal of clinical chemistry. Pages 122947. Oct 26, 2026. Epub Oct 26, 2026.

Abstract

Steroid hormone monitoring is essential in endocrine conditions such as congenital adrenal hyperplasia (CAH), but conventional venous sampling is invasive and often impractical, particularly in children. Capillary microsampling using volumetric absorptive microsampling (VAMS) offers a minimally invasive alternative, suitable for home sampling. However, before embarking on application in patients, it is important to set up a clinical validation study to assess whether -and how- blood (VAMS-based) steroid hormone concentrations can be converted to concentrations in the reference matrix, plasma. Previously described, validated LC-MS/MS methods were used to determine the concentrations of androstenedione (4-AD), 17α-hydroxyprogesterone (17-OHP) and 11-ketotestosterone (11-KT) in paired venous (liquid and dried) and capillary samples collected from 43 healthy adults and 41 children with diabetes. Steroid concentrations were compared across matrices, and capillary VAMS results were converted to plasma values using the hematocrit (hct), derived from dried blood. No methodological differences were observed between dried and liquid (venous VAMS vs. whole blood) samples (>82% within ±20%). Capillary (cVAMS) vs. venous VAMS (vVAMS) samples showed good agreement for 4-AD and 17-OHP but higher variability, particularly for 11-KT. Converting cVAMS values to plasma concentrations using the hct resulted in clinically acceptable agreement with actually measured plasma concentrations for 4-AD, 17-OHP and 11-KT (with 87%, 94% and 72% of the differences within the clinical acceptance limits). While for 11-KT, unexplained differences between the two study populations were apparent, a proof-of-concept application in 5 CAH patients showed good agreement for all analytes. Our results suggest that fingerprick VAMS can be explored as an alternative strategy to conventional plasma collection for monitoring 4-AD, 17-OHP and 11-KT in CAH patients. Nevertheless, assessment of the clinical validity in a larger CAH patient cohort is warranted to confirm the applicability of VAMS as a tool for decentralized steroid monitoring in these patients.

PMID:
42933753
Bibliographic data and abstract were imported from PubMed on 27 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.