Endocrine Abstracts

Introduction: Subclinical thyroid dysfunction is defined as an abnormal serum thyroid-stimulating hormone (TSH) level and free thyroxine (FT4) and triiodothyronin (T3) levels within their reference ranges. The prevalence of subclinical thyroid dysfunction has increased, especially in women older than 60 years. There is good evidence that subclinical hypothyroidism is associated with progression to overt disease, so screening is recommended for high-risk populations. FREND™ Thyroid Duo, a microfluidic immunoassay, was developed to provide a convenient quantitative method for both TSH and FT4 in a single test.

Objective: To evaluate the analytical performance a FREND™ Thyroid Duo immunoassay on FREND™ system.

Method: The analytical performance studies (sensitivity, precision, linearity, interference and accuracy) were performed according to the CLSI protocols (EP17, EP05, EP06, EP07 and EP09). For the method comparison, serum TSH and free T4 were assayed by FREND™ and Architect i1000 (Abbott Diagnostics, Abbott Park, IL, USA).

Results: The FREND™ Thyroid Duo demonstrated acceptable imprecision of %CV (<10%) in low, intermediate, and high level samples for both analytes. The linearity of the assay was found to be acceptable in the range of 0.06–25 mIU/l for TSH and 0.4–6 ng/dl for FT4. Method comparisons between Abbott Architect’s assays and NanoEnTek’s FREND Thyroid Duo assay were made and no significant deviation from linearity was found. No significant interference was observed for both analytes from bilirubin, Intra-lipid and total protein up to concentrations of 20 mg/dl, 3 g/dl, and 12 g/dl respectively.

Conclusion: The NanoEnTek’s FREND™ Thyroid Duo assay represents a rapid, accurate and convenient mean of measuring TSH and FT4 quantities in human serum on FREND™ system. The subclinical thyroid dysfunction may be screened or monitored in a clinic or physician’s office using this microfluidic 2-in-1 thyroid assay with ease and comfort.