Join us   Log in   editor.njbms16@gmail.com  


NJBMS - Volume 6, Issue 4, April - June 2016

Pages: 157-162
Print Article   Download XML  Download PDF

ANALYTICAL SENSITIVITY OF TSH ASSAYS BY ELISA AND ELFA

Author: K.PRAMILA, POONGUZHALI GOPINATH, K.MENAKA SHANTHI, M.DIVYA

Category: Biochemistry

Abstract:

INTRODUCTION : The technological advances from radioimmunoassay to immunometric assays have greatly enhanced the sensitivity of TSH assays over the last three decades and has firmly established TSH as the single most reliable Thyroid function test in assessing the Thyroid hormone status of an individual.

AIMS AND OBJECTIVE : The objective of this current study is to compare the performance of TSH assay based on Enzyme Linked Fluorescent Assay (VIDAS system) with Enzyme Linked Immunosorbant assay technology (Accubind) and also to compare the analytical sensitivity of the TSH assay by the above two technologies.

MATERIALS AND METHODS : Thyroid stimulating hormone levels have been assayed in the serum of 105 patients by both ELISA and ELFA so as to analyze the performance of the above two technologies. The term analytical sensitivity refers to a minimal concentration of TSH that can be detected by an assay with greater confidence.

RESULTS : There exists statistically significant difference between assays by ELISA and ELFA in Euthyroid (p<0.001**) and Hypothyroid samples (p<0.05). The precision CV for Hyperthyroid samples by ELISA range from 7.7% to 39.4% whereas for ELFA the precision CV ranges from 3.4% to 14.5% thus exhibiting the greater analytical sensitivity for ELFA.

CONCLUSION : TSH assay by ELFA has broader functional range, higher analytical sensitivity and also higher specificity compared to TSH assay by ELISA technology.The actual purpose of this study is to fully characterize the analytical performance of the two assays, to understand the capability and limitations of each test so as to ensure that they are fit for routine use.

Keywords: ELISA, ELFA, Thyroid stimulating hormone, analytical sensitivity