Clinical evaluation of thyroglobulin II assay and its impact on clinical management of thyroid diseases

Objective To compare the consistence and difference between the assay results of the second generation of Tg (Tg Ⅱ) and the first generation of Tg (TgⅠ) immunoassay, as well as to evaluate the impact of TgⅡon the clinical management of thyroid diseases. Methods Serum samples of 249 patients (30 with benign thyroid disorders and 219 with DTC; 64 males and 185 females, average age 43.0 years) were collected and assayed by TgⅡand TgⅠ kits simultaneously. The measuring ranges of TgⅠ and TgⅡ were 0.10-1 000.00 μg/L and 0.04-500.00 μg/L, respectively. Data were analyzed by the Wilcoxon rank sum test and Spearman correlation analysis using IBM SPSS 19.0. Results The assay results of TgⅡ and TgⅠ strongly correlated(rs=0.979, P 1.0 μg/L but TgⅡ 0.1 μg/L but TgⅡ<0.04 μg/L. Conclusions Serum TgⅡand TgⅠ assay results are strongly correlated, though TgⅡvalue is slightly lower than TgⅠvalue. This difference may have no significant influence on the clinical diagnosis of thyroid diseases. However, TgⅡ may be better to evaluate the curative effect in some DTC patients post 131I therapy. Key words: Thyroid diseases; Thyroglobulin; Diagnosis; Prognosis