Implementation of Volumetric Finger-Prick Self-Sampling for Therapeutic Drug Monitoring of Immunosuppressants After Kidney Transplantation: Lessons Learned From the Practice
Vethe et al.
The finding, in our words
The paper summarises that volumetric finger-prick self-sampling is suitable for monitoring immunosuppressants and biomarkers after kidney transplantation, but successful implementation requires careful design of the entire workflow, including patient training and method validation. This matters because it provides a real-world framework for moving critical monitoring from the clinic to the patient's home.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
This review found that volumetric microsampling devices, such as Mitra, HemaPEN, HemaXis DB10, and Tasso-M20, overcome haematocrit bias, whilst Telimmune plasma separation cards enable direct plasma collection without centrifugation. These technologies support patient-centric, decentralised sampling, though the authors note that clinical validation remains limited across different drugs and patient populations.
A validated offline SPE-LC-MS/MS method using the Mitra microsampling device successfully quantified tacrolimus, cyclosporine A, tryptophan, kynurenine, and creatinine simultaneously. The method met EMA and FDA criteria, showing agreement between capillary and venous sampling, which could facilitate decentralised therapeutic drug monitoring and transplant follow-up through patient self-collection.
A study of 37 kidney transplant recipients found Capitainer and Mitra microsampling feasible for decentralised monitoring. Capitainer showed consistent sampling success, 92%-96%, and higher analytical accuracy than Mitra, 52%-88% success. Proportions within ±15% of venous reference for creatinine and haemoglobin were 92%-100% and 93%-100% for Capitainer, versus 79%-96% and 67%-92% for Mitra, despite small cohorts.
Clinical validation for tacrolimus and mycophenolic acid monitoring showed that while volumetric absorptive microsampling met analytical criteria after concentration correction, conventional dried blood spots achieved superior adherence to strict clinical criteria, sample quality, and cost efficiency without significant haematocrit bias.