Milinković Neda, Sarić Marija, Ružanović Ana, Žarković Miloš, Ćirić Jasmina, Perović Blagojević Iva, Mastilović Ana-Marija, Ignjatović Svetlana, Nedeljković Beleslin Biljana
University of Belgrade, Faculty of Pharmacy, Department of Medical Biochemistry, Belgrade.
University Clinical Center of Serbia, Clinic of Endocrinology, Belgrade, Serbia.
J Med Biochem. 2025 Jun 13;44(3):438-446. doi: 10.5937/jomb0-55873.
Despite commercially improved, standardised routine methods used in medical laboratories, precision laboratory medicine lacks harmonisation of results to make the laboratory result useful for its intended purpose. Furthermore, to obtain reliable laboratory results and precise diagnoses, it is important and recommended that each laboratory confirms the analytical and clinical characteristics of the method used. This study aimed to evaluate the analytical and clinical performance of the IMMULITE®2000 TSI bridge immunoassay to determine autoreactive thyroid stimulating hormone receptor antibodies (SH-R-Ab).
A total of 86 patients with clinically present Graves' orbitopathy and 23 healthy volunteers as a control group were included in the study. The total TSH-R-Ab concentration was determined using an ECLIA (Elecsys Anti-TSHR Immunoassay Roche Diagnostics, GmbH, Mannheim, Germany) on the Cobas e411 analyser (Roche, Diagnostics, GmbH). The TSH-R-Ab concentration was measured using a CLIA method (IMMULITE TSI 2000, Siemens Healthcare Diagnostics, UK). The inaccuracy of the method was investigated using two levels of commercial control samples (low and high analyte concentration).
The results obtained meet the general minimum requirements for the analytical performance of laboratory methods (CV<5%). The overall laboratory inaccuracy was acceptable according to FDA guidelines (CV<20%). The results showed a statistically significant correlation between the analysed methods (r=0.9041, p < 0.0001) but with a relative bias of 24.5%. The best ratio of sensitivity and specificity determined by the ROC analysis (93.3% and 100%, respectively) was obtained for a cut-off value of 0.1215 IU/L, which is significantly lower compared to the cut-off value specified by the manufacturer (0.55 IU/L).
The IMMULITE 2000 TSI bridge immunoassay for TSH-R-Ab quantification confirmed adequate precision, which is essential for routine use. However, further studies are required to evaluate its analytical specificity.
尽管医学实验室使用的商业常规方法有所改进且标准化，但精准检验医学缺乏结果的一致性，使得实验室结果无法用于预期目的。此外，为获得可靠的实验室结果和准确的诊断，每个实验室确认所用方法的分析和临床特征非常重要且值得推荐。本研究旨在评估IMMULITE®2000 TSI桥联免疫分析法测定自身反应性促甲状腺激素受体抗体（SH-R-Ab）的分析性能和临床性能。
本研究共纳入86例临床诊断为格雷夫斯眼眶病的患者及23名健康志愿者作为对照组。使用罗氏诊断有限公司（德国曼海姆）的Elecsys Anti-TSHR免疫分析法在Cobas e411分析仪（罗氏诊断有限公司）上测定促甲状腺激素受体抗体（TSH-R-Ab）的总浓度。使用化学发光免疫分析法（IMMULITE TSI 2000，西门子医疗诊断公司，英国）测量TSH-R-Ab浓度。使用两种水平的商业对照样品（低分析物浓度和高分析物浓度）研究该方法的不准确性。
获得的结果符合实验室方法分析性能的一般最低要求（变异系数<5%）。根据美国食品药品监督管理局的指南，整体实验室不准确性是可接受的（变异系数<20%）。结果显示分析方法之间具有统计学显著相关性（r=0.9041，p<0.0001），但相对偏差为24.5%。通过ROC分析确定的最佳灵敏度和特异性比值（分别为93.3%和100%）对应的临界值为0.1215 IU/L，与制造商规定的临界值（0.55 IU/L）相比显著更低。
用于定量TSH-R-Ab的IMMULITE 2000 TSI桥联免疫分析法确认了足够的精密度，这对于常规使用至关重要。然而，需要进一步研究以评估其分析特异性。
