Serum biotin interference: A troublemaker in hormone immunoassays

Area of Science:

• Clinical Chemistry
• Biochemistry
• Endocrinology

Background:

• Biotin therapy is known to interfere with various immunoassay results.
• Accurate measurement of 25-hydroxy vitamin D (25-OHD), parathyroid hormone (PTH), and thyroid-stimulating hormone (TSH) is crucial for patient diagnosis and management.

Purpose of the Study:

• To investigate the interference of biotin on 25-OHD, PTH, and TSH assays.
• To evaluate the effectiveness of biotin neutralization using Streptavidin-coated magnetic particles (SMP).

Main Methods:

• Fifty children with biotinidase deficiency (BTD) undergoing biotin treatment were analyzed.
• Assays for 25-OHD, PTH, and TSH were performed using Roche Diagnostics and Beckman Coulter systems, alongside HPLC and LC/MS-MS.
• Biotin neutralization was achieved using SMP before and after sample analysis.

Main Results:

• Biotin interference was observed in Roche assays for 25-OHD, PTH, and TSH.
• Significant differences in results were noted after biotin neutralization with the Roche assay for 25-OHD (decrease) and PTH (increase).
• TSH levels also increased significantly in the Roche assay after neutralization.

Conclusions:

• High biotin concentrations significantly affect Roche assay results for PTH, 25-OHD, and TSH, posing a risk of misdiagnosis.
• SMP-based biotin neutralization effectively eliminates interference in these immunoassays.
• Clinical laboratories should consider biotin interference when interpreting results from specific assay systems.