2026 · Clinical chemistry and laboratory medicine · paywalled
Patient-centric capillary dried blood spot sampling for tacrolimus and creatinine monitoring in clinical practice
De Baets et al.
The finding, in our words
The study found that quantitative dried blood spot sampling provided high clinical agreement for tacrolimus and creatinine monitoring, with patients rating the self-collection devices as user-friendly. These results support the feasibility of decentralised therapeutic drug monitoring for immunosuppressants.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
VAMS microsampling found no significant difference from venous blood for tacrolimus in paediatric patients; samples were stable for 14 days, with average difference between paired at-home samples of 0.12 ± 0.94 ng/mL.
At-home volumetric absorptive microsampling (VAMS) for anti-seizure medicines was feasible and reliable, with strong correlations to clinic VAMS and low bias for lacosamide, lamotrigine and levetiracetam; quantitative dried blood spot (qDBS) was a reliable alternative in the ambulatory setting, though older age reduced sampling quality.
Home DBS sampling gave testosterone results that agreed well with venous blood in men on intramuscular testosterone undecanoate, but showed falsely high values in those using topical gel, likely from skin contamination. Patients preferred home collection for its convenience, suggesting DBS is viable for decentralised monitoring of injectable testosterone if patients are taught proper technique.
Microsampling, particularly VAMS and quantitative DBS, can enable patient-centric therapeutic drug monitoring of immunosuppressants after transplantation, allowing home self-sampling and long-term monitoring when patients live far from transplant centres. These volumetric dried formats have largely overcome the haematocrit effect and sample heterogeneity that limit conventional dried blood spots.
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.