2025 · Alzheimer's & dementia : the journal of the Alzheimer's Association · open access
The detection of GRN mutation carriers by progranulin blood protein levels from finger-stick collection
Huber et al.
The finding, in our words
Finger-stick dried blood spots accurately measured progranulin levels, showing strong agreement with venous plasma (r=0.93) and high diagnostic accuracy (AUC=0.99) for detecting GRN mutation carriers in frontotemporal dementia. This patient-centric microsampling method could enable decentralised screening and remote therapeutic monitoring, circumventing the need for traditional venous collection.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
A 2025 review maps 28 microsampling devices, from dried spots and volumetric absorptive tips to upper-arm liquid capillary collectors, and names what a laboratory must control before their results are used: the haematocrit effect in non-volumetric dried samples, interstitial fluid from finger milking, volume, haemolysis and transport stability. Regulators on both sides of the Atlantic ask for the same two things, a device the patient can use safely and a sample fit for the test.
An IQ Consortium position paper from sponsor scientists positioning patient-centric sampling as the enabling technology for decentralised trials, and stating that a bridging study against conventional sampling “has quickly been established as a regulatory expectation”.
Maass et al., Clinical and Translational Science · source ↗
Merck describes a digitally enabled, patient-centric trial initiative that combines outpatient PK/PD sampling with digital biomarkers and smart dosing technologies to improve exposure-response understanding and reduce patient burden, while acknowledging adoption challenges.
Dockendorf et al., Clinical and translational science · source ↗
Capillary dried blood spots, after haematocrit-dependent conversion, showed good agreement with plasma for 25-hydroxyvitamin D quantification, with 90 per cent of results within 20 per cent of plasma and substantial to almost perfect agreement in status classification, supporting reliable home self-collection for large-scale vitamin D monitoring.
Heughebaert et al., Clinical chemistry and laboratory medicine (paywalled) · source ↗
This study validated a dried blood spot method for tacrolimus monitoring and demonstrated agreement with venous whole blood measurements in kidney transplant recipients. It also found that dried blood spot analysis of the biomarker CXCL-10 was elevated in patients experiencing rejection or infection, supporting its use for decentralised monitoring.