Nadkarni S, Allen L C
Department of laboratory Medicine and Pathobiology, Toronto Hospital, Ontario, Canada.
Clin Biochem. 1998 Mar;31(2):89-94. doi: 10.1016/s0009-9120(97)00173-2.
To evaluate the Ames, Randox, Roche, and Synermed methods for the measurement of serum iron and to investigate patterns of possibly discrepant results in dialysis patients.
Assays were performed on the Cobas Fara II analyzer. Precision and accuracy studies were conducted; recovery studies were done by adding pooled serum from dialysis patients to an assayed human serum-based control. Patient comparisons included over 150 nondialysis patients and 30 dialysis patients.
For the Ames, Randox, Roche and Synermed methods, the between-run precision was less than 2.80% with the normal aqueous iron standard; 2.00, 2.70, 0.80, and 2.00% for the four methods with the high serum iron control, respectively, and less than 2.30% with the serum pool. Using a pooled serum from dialysis patients, between-run precision was higher with all four methods. With an abnormal assayed human serum-based control, accuracy was over 98% for the four methods. Recoveries were 121% for the Ames and Randox methods and 104-105% for the Roche and Synermed methods. Accuracy as assessed with Murex EQAS specimens ranged from 71 to 80%, 71 to 96%, 98 to 99.5%, and 42 to 50% for the four methods, respectively. For comparisons of the Ames, Randox, and Roche methods with the Synermed method, difference analyses revealed biases (SD) for nondialysis patients of 1.9 (2.7), 1.5 (3.3), and 1.8 (2.2) mumol/L, respectively; and for dialysis patients of 8.2 (13.3), 5.1 (5.4), and 1.4 (1.7) mumol/L. Standard linear regression analyses and correlation coefficients are also provided.
The Roche method was slightly more precise than the other methods. Using an abnormal assayed serum-based control, all methods showed good accuracy. Recovery studies with pooled serum from dialysis patients showed interferences with the Ames and Randox methods and good recovery with the Roche and Synermed methods. With the bovine serum-based Murex samples, all but the Roche method yielded some low results; the Synermed method has been reported to suffer from matrix problems with bovine serum albumin. Based on recovery studies and difference analyses, the Ames and Randox methods revealed discrepancies in iron results for samples from dialysis patients. The Roche and Synermed methods appeared to be suitable for measurement of serum iron in dialysis patients.
评估用于测定血清铁的艾姆斯（Ames）、朗道（Randox）、罗氏（Roche）和西奈美（Synermed）方法，并研究透析患者中可能出现差异结果的模式。
在Cobas Fara II分析仪上进行检测。开展了精密度和准确度研究；通过将透析患者的混合血清添加到经检测的基于人血清的对照中来进行回收研究。患者比较包括150多名非透析患者和30名透析患者。
对于艾姆斯、朗道、罗氏和西奈美方法，使用正常水性铁标准时批间精密度小于2.80%；使用高血清铁对照时，四种方法分别为2.00%、2.70%、0.80%和2.00%，使用血清池时小于2.30%。使用透析患者的混合血清时，所有四种方法的批间精密度更高。使用异常的经检测的基于人血清的对照时，四种方法的准确度均超过98%。艾姆斯和朗道方法的回收率为121%，罗氏和西奈美方法的回收率为104 - 105%。用Murex EQAS标本评估时，四种方法的准确度分别为71%至80%、71%至96%、98%至99.5%和42%至50%。对于艾姆斯、朗道和罗氏方法与西奈美方法的比较，差异分析显示非透析患者的偏差（标准差）分别为1.9（2.7）、1.5（3.3）和1.8（2.2）μmol/L；透析患者的偏差分别为8.2（13.3）、5.1（5.4）和1.4（1.7）μmol/L。还提供了标准线性回归分析和相关系数。
罗氏方法比其他方法稍精确。使用异常的经检测的基于血清的对照时，所有方法均显示出良好的准确度。用透析患者的混合血清进行的回收研究表明，艾姆斯和朗道方法存在干扰，罗氏和西奈美方法回收率良好。对于基于牛血清的Murex样本，除罗氏方法外，其他方法均得出一些较低结果；据报道，西奈美方法存在牛血清白蛋白基质问题。基于回收研究和差异分析，艾姆斯和朗道方法在透析患者样本的铁结果上存在差异。罗氏和西奈美方法似乎适用于透析患者血清铁的测定。
