Abstract
Objectives
Chromogenic anti-activated factor X (FXa) assays are currently the “gold standard” for monitoring indirect anticoagulants. However, anti-FXa has been shown to vary according to the choice of reagents. In the present study, the performance of anti-FXa measurement was evaluated in order to gain more insight into the clinical applications. Furthermore, the longitudinal coefficient of variation (CV) was studied to investigate whether there is improvement over time.
Methods
Laboratory tests results were evaluated for samples spiked with unfractionated heparin (UFH), low-molecular-weight-heparin (LMWH), fondaparinux and danaparoid sodium. External quality assessment (EQA) data from multiple years were used from more than 100 laboratories.
Results
Comparison of the results for all methods showed significant differences in measured values between the frequently used methods (ANOVA: p < 0.001). The largest differences were observed for LMWH and UFH measurements. These differences may be caused by differences in method composition, such as the addition of dextran sulphate. Substantial interlaboratory variation in anti-FXa monitoring was observed for all parameters, particularly at low concentrations. Our results showed that below 0.35 IU/mL, the CVs for UFH and LMWH increase dramatically and results below this limit should be used with caution.
Conclusions
Our study demonstrates that the choice of the anti-FXa method is particularly important for UFH and LMWH measurement. The variation in measurements may have an effect on clinical implications, such as therapeutic ranges. Furthermore, the longitudinal EQA data demonstrated a constant performance and, in at least 50% of the cases, improvement in the CV% of the anti-Xa results over time.
Acknowledgments
The authors would like to acknowledge Dr. P. Tsiamyrtzis for his statistical support.
Research funding: None declared.
Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: Authors state no conflict of interest.
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©2020 Walter de Gruyter GmbH, Berlin/Boston
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Articles in the same Issue
- Frontmatter
- Editorial
- Biotin interference in cardiac troponin immunoassay – where the wild things are?
- Review
- Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays
- Mini Review
- Chromatographic methods development for clinical practice: requirements and limitations
- Opinion Paper
- Harmonising EQA schemes the next frontier: challenging the status quo
- Genetics and Molecular Diagnostics
- Direct comparison study between droplet digital PCR and a combination of allele-specific PCR, asymmetric rapid PCR and melting curve analysis for the detection of BRAF V600E mutation in plasma from melanoma patients
- A novel mitochondrial m.14430A>G (MT-ND6, p.W82R) variant causes complex I deficiency and mitochondrial Leigh syndrome
- Obesity status modifies the association between rs7556897T>C in the intergenic region SLC19A3-CCL20 and blood pressure in French children
- General Clinical Chemistry and Laboratory Medicine
- Influence of reagent lots and multiple measuring systems on estimating the coefficient of variation from quality control data; implications for uncertainty estimation and interpretation of QC results
- Electrophoretic α1-globulin for screening of α1-antitrypsin deficient variants
- A continued method performance monitoring approach for the determination of pediatric renin samples – application within a European clinical trial
- Pilot study for cystic fibrosis neonatal screening: the Cuban experience
- Validation of the analytical performance of the NOVEOS™ System, a system which improves upon the third-generation in vitro allergy testing technology
- IgE cross-reactivity measurement of cashew nut, hazelnut and peanut using a novel IMMULITE inhibition method
- Sexual dimorphism in the cerebrospinal fluid total protein content
- Current state of the morphological assessment of urinary erythrocytes in The Netherlands: a nation-wide questionnaire
- Reference Values and Biological Variations
- Within-subject and between-subject biological variation of first morning void urine amino acids in 12 healthy subjects
- Proenkephalin as a new biomarker for pediatric acute kidney injury – reference values and performance in children under one year of age
- Hematology and Coagulation
- Quality performance for indirect Xa inhibitor monitoring in patients using international external quality data
- Cardiovascular Diseases
- Clinical risk assessment of biotin interference with a high-sensitivity cardiac troponin T assay
- Short- and long-term biological variation of cardiac troponin I in healthy individuals, and patients with end-stage renal failure requiring haemodialysis or cardiomyopathy
- Infectious Diseases
- Monocyte distribution width (MDW) as a screening tool for sepsis in the Emergency Department
- Performance of a Toxo IgM prototype assay for the diagnosis of maternal and congenital Toxoplasma infections
- Letters to the Editors
- Evaluation of an ELISA for SARS-CoV-2 antibody testing: clinical performances and correlation with plaque reduction neutralization titer
- Preliminary evaluation of Roche Cobas Elecsys Anti-SARS-CoV-2 chemiluminescence immunoassay
- Hypoalbuminemia and elevated D-dimer in COVID-19 patients: a call for result harmonization
- Total pathway to method validation
- Derivation of performance specifications for uncertainty of serum C-reactive protein measurement according to the Milan model 3 (state of the art)
- FGF23 measurement in burosumab-treated patients: an emerging treatment may induce a new analytical interference
- Use of a modified IDS-ISYS intact PTH assay for intraoperative PTH measurements
- Agreement of dried blood spot lyso-Gb3 concentrations obtained from different laboratories in patients with Fabry disease
- Influence of delayed separation of plasma from whole blood and centrifugation protocol on Zn plasma concentration
- A survey of order of draw on inpatient wards and adherence to EFLM-COLABIOCLI recommendations
- Successful implementations of automated minimum re-test intervals to overcome ferritin over-requesting in a Spanish hospital laboratory
- Remarkable pseudoleucocytosis induced by mild cryoglobulinemia
- Massive hemolysis due to Clostridium perfringens: a laboratory’s perspective