2023 · European journal of clinical pharmacology · paywalled
Reliability and feasibility of home-based dried blood spot in therapeutic drug monitoring: a systematic review and meta-analysis
Xiaoyong et al.
The finding, in our words
Dried blood spot sampling shows moderate agreement with plasma for therapeutic drug monitoring across evaluated drugs, and home based DBS achieves high yield and adherence with patient preference around three quarters; DBS is a reliable and feasible option for decentralised TDM but needs careful design and evaluation before use.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
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.
The study found that dried blood spot sampling showed good agreement with plasma concentrations for vancomycin and creatinine, with most differences within 20%, and patients preferred the finger prick method over venepuncture, supporting its use for decentralised therapeutic drug monitoring.
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.
In AML and CLL, 91% of VAMS venetoclax results fell within 20% of plasma after individualised haematocrit correction; in home sampling, 18 of 21 patients self-sampled independently and 76% of returned samples were analysable, which shows home microsampling is workable, though the authors ask for multicentre validation.
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.