Implementation of Volumetric Finger-Prick Self-Sampling for TDM of Immunosuppressants After Kidney Transplantation: Lessons Learned from the Practice

Nils Tore Vethe; Anders Åsberg; Stein Bergan; Ida Robertsen; Karsten Midtvedt

doi:10.1097/FTD.0000000000001281

Implementation of Volumetric Finger-Prick Self-Sampling for TDM of Immunosuppressants After Kidney Transplantation: Lessons Learned from the Practice

Ther Drug Monit. 2024 Nov 19. doi: 10.1097/FTD.0000000000001281. Online ahead of print.

Authors

Nils Tore Vethe^{1

2}, Anders Åsberg^{2

3}, Stein Bergan^{1

2}, Ida Robertsen², Karsten Midtvedt³

Affiliations

¹ Department of Pharmacology, Oslo University Hospital, Oslo, Norway.
² Department of Pharmacy, University of Oslo, Oslo, Norway; and.
³ Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway.

PMID: 39560611
DOI: 10.1097/FTD.0000000000001281

Abstract

Background: Home-based hospital services are becoming increasingly popular, and the addition of remote outpatient appointments after kidney transplantation facilitates more practical and closer follow-up. In this context, finger-prick self-sampling is an important aspect of monitoring of immunosuppressants and biomarkers. Nevertheless, several issues must be addressed to ensure the feasibility and quality when implementing microsampling in clinical practice. We summarize our experiences and opinions in this field.

Methods: This article is based on the authors' experience regarding the laboratory and clinical implementation of finger-prick self-sampling in kidney transplant recipients. The referenced literature is related to the authors' knowledge in this field.

Results: We present considerations for the selection of relevant analytes, key characteristics of selected volumetric sampling tools (Mitra and Capitainer), and the associated sampling pitfalls. In addition, we address the requirements for patients performing finger-prick sampling, appropriate design of methods and workflow, critical points for validation, and aspects related to logistics and digital solutions.

Conclusions: Volumetric finger-prick self-sampling is suitable for monitoring immunosuppressants and certain biomarkers that are relevant to outpatient follow-up after kidney transplantation. We believe that a carefully designed system for the entire workflow, including patient training, will be beneficial in enabling a safe experience for transplant recipients, as well as ensuring overall efficiency and adequate quality. In the future, a combination of immunosuppressants with a wide range of biomarkers has significant potential for use in at-home self-sampling after kidney transplantation.