Dried Blood Spot Sampling for Tacrolimus and Mycophenolic Acid in Children: Analytical and Clinical Validation

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.

VAMS and parallel-reaction-monitoring mass spectrometry for tacrolimus trough measurements at home in paediatric heart-transplant patients — Zhao et al., J. Mass Spectrometry and Advances in the Clinical Lab · source ↗

• vams
• venous-agreement
• acceptability
• blood
• dbs
• tdm
• self-collection
• dried
• capillary
• pediatric
• immunosuppressants
• validation

A systematic review of dried blood spot sampling for tacrolimus monitoring across adult and paediatric organ transplant recipients demonstrated that reported analytical bias compared with venous sampling fell within acceptable limits across the majority of studies. This supports dried blood microsampling as an accurate approach for decentralised therapeutic drug monitoring.

Predictability of Capillary Blood Spot Toward Venous Whole Blood Sampling for Therapeutic Drug Monitoring of Tacrolimus in Solid Organ Transplant Recipients — Gallant et al., European journal of drug metabolism and pharmacokinetics (paywalled) · source ↗

• blood
• dried
• capillary
• dbs
• validation
• venous-agreement
• pediatric
• tdm
• immunosuppressants

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.

Dried Blood Spot for CXCL-10 and Tacrolimus: Integrated Non-Invasive Monitoring to Guide Personalized Treatment in Adult Kidney Transplant Recipients — Millán et al., Pharmaceuticals · source ↗

• venous-agreement
• blood
• dbs
• tdm
• dried
• immunosuppressants
• validation
• biomarkers

This study validated a method for monitoring mycophenolic acid in paediatric patients, demonstrating that quantitative dried plasma spots achieved close agreement with venous plasma. Quantitative dried blood spots showed significant haematocrit-related bias, making the plasma-based format more suitable for decentralised monitoring.

Matrix fidelity in microsampling: Plasma-first LC-MS/MS quantification of mycophenolic acid and MPAG — Kocur et al., Journal of chromatography. B, Analytical technologies in the biomedical and life sciences (paywalled) · source ↗

• venous-agreement
• blood
• qdbs
• tdm
• haematocrit
• dried
• pediatric
• immunosuppressants
• validation

In matched clinical samples from rheumatoid arthritis, VAMS and DBS showed strong agreement for methotrexate polyglutamates (slopes 0.95-1.07; bias within -4.21% to 0.36%; SRCC ≥ 0.969), with up to 100% of total MTXPG results within ±20% limits; capillary microsampling agreed closely with whole blood but differed from red blood cells, indicating matrix-specific differences that must be accounted for when interpreting against RBC-based reference values.

Multi-Matrix LC-MS/MS Validation of Methotrexate Polyglutamates: Comparison of VAMS, DBS, and Conventional Blood Sampling in Rheumatoid Arthritis — Kocur et al., International journal of molecular sciences · source ↗

• vams
• venous-agreement
• neoteryx-mitra
• blood
• dbs
• tdm
• dried
• capillary
• immunosuppressants
• validation