A novel dried blood spot-LCMS method for the quantification of methotrexate polyglutamates as a potential marker for methotrexate use in children
Hawwa et al.
The finding, in our words
The authors developed and validated a sensitive LCMS assay for methotrexate polyglutamates in dried blood spots from finger-prick samples, demonstrating agreement with conventional HPLC-UV analysis of matched red-cell samples in 47 paediatric patients. This enables minimally invasive, parent-collected sampling at home for therapeutic drug monitoring, supporting decentralised clinical studies and care in paediatric rheumatology.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
A systematic review found mixed economic evidence for microsampling in therapeutic drug monitoring; one study reported no cost reduction with DBS home-sampling, €688 versus €676, whilst another predicted savings up to 61%. The authors caution that more work is required to assess costs alongside clinical outcomes and optimise logistics for decentralised implementation.
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.
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.
Clinical validation in twenty-eight children showed that dried blood spot sampling predicted venous tacrolimus concentrations adequately, with ninety-five percent of predicted-to-observed ratios between 0.74 and 1.28 and median prediction error below fifteen percent, whereas mycophenolic acid predictions were more variable, indicating semiquantitative utility. The authors concluded that home-based dried blood spot collection is suitable for tacrolimus therapeutic drug monitoring in paediatric transplant recipients.
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.