Sacks D B, Lim M M, Parvin C A, Kessler G
Department of Pathology, Washington University School of Medicine, St. Louis, MO 63110.
Clin Chem. 1990 Jul;36(7):1343-5.
In a previous evaluation of a "sensitive" radial partition fluorescent immunoassay on the Stratus system, thyrotropin (TSH) values exhibited a positive bias in icteric samples when compared with results of a nonsensitive radioimmunoassay. In the present study, we evaluated 366 patients samples to assess whether any biochemical markers of liver function could identify samples for which TSH values would be falsely increased. gamma-Glutamyltransferase and total bilirubin concentrations were unrelated to discrepant TSH values. In contrast, alkaline phosphatase (ALP) was significantly positively correlated with differences in Stratus and RIA TSH concentrations (P less than 0.001). However, this correlation explained only 34% of the observed residual variability around the estimated regression line. On average, the higher ALP values were associated with larger discrepancies between Stratus and RIA TSH values, although several samples with increased ALP did not have falsely increased Stratus TSH values. TSH measurements performed with a Stratus should be interpreted with caution in patients with abnormal biochemical markers of liver function.
在之前对Stratus系统上一种“灵敏”的放射免疫分析方法进行的评估中，与非灵敏放射免疫分析结果相比，促甲状腺激素（TSH）值在黄疸样本中表现出正偏差。在本研究中，我们评估了366份患者样本，以确定是否有任何肝功能生化标志物能够识别出TSH值会被错误升高的样本。γ-谷氨酰转移酶和总胆红素浓度与TSH值的差异无关。相比之下，碱性磷酸酶（ALP）与Stratus系统和放射免疫分析TSH浓度的差异显著正相关（P<0.001）。然而，这种相关性仅解释了估计回归线周围观察到的残余变异性的34%。平均而言，较高的ALP值与Stratus系统和放射免疫分析TSH值之间的较大差异相关，尽管一些ALP升高的样本其Stratus系统TSH值并未被错误升高。对于肝功能生化标志物异常的患者，使用Stratus系统进行TSH测量时应谨慎解释结果。
