A Dilution Method to Mitigate Biotin Interference in Cardiac Troponin T Testing.
Nicholas J Bevins1, Jacqueline A Hubbard1, Robert L Fitzgerald1
1Department of Pathology, University of California at San Diego, San Diego, CA.
The Journal of Applied Laboratory Medicine
|October 30, 2019
Summary
Oral biotin supplementation can interfere with cardiac troponin T (cTnT) tests, potentially delaying myocardial infarction (MI) diagnosis. A 1:10 dilution with known cTnT serum effectively mitigates this biotin interference.
Area of Science:
- Clinical Chemistry
- Biochemistry
- Medical Diagnostics
Background:
- Oral biotin supplementation is a common practice.
- Biotin interferes with biotin-streptavidin-based immunoassays, including cardiac troponin T (cTnT) assays.
- This interference can impact the diagnosis of myocardial infarction (MI).
Purpose of the Study:
- To investigate biotin interference in Roche's fifth-generation cTnT assay.
- To evaluate the utility of dilution as a method to detect and remove biotin interference.
Main Methods:
- Clinical serum samples were supplemented with biotin.
- cTnT concentrations were measured before and after biotin addition.
- Serum dilution methods were tested to assess interference removal.
Main Results:
- Significant interference observed with biotin concentrations >50 ng/mL near the 100 ng/L cTnT reporting range.
- Autodilution (1:10) was ineffective in mitigating biotin interference.
- A 1:10 dilution with serum containing 20-30 ng/L cTnT successfully detected biotin interference.
Conclusions:
- Supraphysiologic biotin concentrations can artifactually lower cTnT levels, potentially delaying MI diagnosis.
- Dilution with a known low cTnT serum (20-30 ng/L) is an effective method to mitigate biotin interference.
