2024 · The journal of applied laboratory medicine · paywalled
Patient-Centric Quantitative Microsampling for Accurate Determination of Urine Albumin to Creatinine Ratio (UACR) in a Clinical Setting
Löfgren et al.
The finding, in our words
In 102 patients, Mitra and Capitainer microsamples gave urine albumin-to-creatinine ratios at 102% and 95% of the clinical analyser's, and both stayed within 98% to 103% after three weeks at room temperature, which supports either device for decentralised urine collection.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
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 dried urine spot method for measuring 14 amino acids was validated using filter paper and mass spectrometry, offering a stable alternative to liquid urine that supports patient self-collection and remote analysis.
Low volume sampling devices showed good concordance with venous serum for measuring the pharmacodynamic biomarker sMAdCAM-1, but dried blood samples required substantial dilution to overcome buffer interference, which was mitigated by using a highly sensitive Simoa assay. The study demonstrates that while these devices have potential for decentralised clinical trials, careful validation is needed to address site-specific biases and assay sensitivity limitations.
The study compared VAMS capillary finger prick samples with venous liquid and venous VAMS samples from 50 healthy volunteers for thiamine diphosphate measurement, finding 94 to 100 per cent of results within 20 per cent of their mean across all comparisons with no significant bias. VAMS microsamples also remained stable when sent through regular post without affecting results, supporting their use for decentralised thiamine status assessment in both developed and remote settings.
Researchers successfully validated an analytical method for measuring creatinine across plasma and volumetric absorptive microsampling devices, demonstrating strong correlation between conventional plasma and dried microsamples. This provides a reliable, patient-centric approach for monitoring kidney function remotely during transplant follow-up.