Journal article
Characterization of bilirubin interference in three commonly used digoxin assays
Clinical biochemistry, Vol.63, pp.102-105
01/2019
DOI: 10.1016/j.clinbiochem.2018.10.006
PMID: 30316751
Abstract
Due to the narrow therapeutic range of digoxin, determining serum/plasma digoxin concentrations is critical for assessing patients with congestive heart failure, atrial fibrillation, and certain types of arrhythmias. However, digoxin quantification by competitive immunoassays is susceptible to interferences that may alter the accuracy of its measurement in patient plasma. This study aimed to characterize the extent of bilirubin interference in three commonly used digoxin immunoassays.
Digoxin concentrations were compared using the Beckman Coulter® Unicel DxI 800, the Vitros® 4600, and the Roche Cobas® 8000 in neat or digoxin-spiked icteric and non-icetric plasma samples. A mixing study was performed to demonstrate how digoxin quantification is affected by bilirubin. An equation was derived that predicts the response of the DxI 800, given known bilirubin and digoxin concentrations.
The DxI reported detectable concentrations of digoxin in high bilirubin samples with no added digoxin, while the Vitros® 4600 and Cobas® 8000 gave virtually undetectable results. Spiking digoxin into samples with elevated bilirubin concentrations resulted in a higher percent recovery for the DxI 800 when compared to the other two platforms. The mixing study also revealed an increase in the percent recovery in the DxI 800, while the Vitros® 4600 and Cobas® 8000 were comparable to the expected concentration of digoxin.
The DxI 800 is most prone to interference by bilirubin, while the Vitros® 4600 and Cobas® 8000 are relatively unaffected. Icteric samples should be interpreted with caution if digoxin quantification is needed, especially on the DxI 800 assay.
Details
- Title: Subtitle
- Characterization of bilirubin interference in three commonly used digoxin assays
- Creators
- Paul D Simonson - University of WashingtonKatie H Kim - University of WashingtonGabrielle Winston-McPherson - University of WashingtonRugvedita S Parakh - University of WashingtonDiane Yamaguchi - University of WashingtonAnna E Merrill - University of IowaJane A Dickerson - University of WashingtonDina N Greene - University of Washington
- Resource Type
- Journal article
- Publication Details
- Clinical biochemistry, Vol.63, pp.102-105
- DOI
- 10.1016/j.clinbiochem.2018.10.006
- PMID
- 30316751
- NLM abbreviation
- Clin Biochem
- ISSN
- 0009-9120
- eISSN
- 1873-2933
- Publisher
- Elsevier Inc
- Language
- English
- Date published
- 01/2019
- Academic Unit
- Pathology; Injury Prevention Research Center
- Record Identifier
- 9984186418802771
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