Interference of eltrombopag (PROMACTA®) on Total Bilirubin
Tuesday, March 10, 2020
This communication is to inform you of an interference caused by the drug, eltrombopag (PROMACTA®), on the measurement of total bilirubin when the test is performed on the Siemens Dimension Vista® analyzer, the analyzer in use at Laboratory Alliance. Eltrombopag can cause a positive bias in total bilirubin (false elevation) when the drug is present in the patient at therapeutic levels. Health care providers should, therefore, monitor total bilirubin levels for discordant results for patients who take the drug. Interference has not been observed with the direct bilirubin assay.
The potential clinical impact of a falsely elevated total bilirubin can be mitigated by its correlation to clinical symptomology and to additional laboratory testing, including other markers of liver function (e.g., alanine aminotransferase, aspartate aminotransferase and or alkaline phosphatase).