血清尿素参考方法的建立以及临床常用试剂盒的比对研究

Establishment of Reference Method for Serum Urea Detection and Comparison with Routine Urea Kits

目的建立血清尿素测定的酶偶联平衡的参考方法(紫外分光光度法),对此方法进行性能验证,并评价4种临床常用的试剂盒是否可以接受。方法以美国CDC推荐的血清尿素酶偶联平衡候选参考方法为依据建立本实验的参考方法;通过测定标准物质(SRM909b),以及参加RELA-2009比对实验(ring-tiral),来验证参考方法的准确性;按CLSI《EP9-A2》要求,以酶偶联平衡参考方法作为比对方法,4种临床常用的检测试剂盒为待评方法,对40份血清样品的结果进行分析比较。结果用酶偶联平衡参考方法测定SRM909b水平1和2,与靶值的偏倚分别为2.19%,0.24%;参加参考实验室国际比对,血清尿素结果在可接受范围内;4种常用的试剂盒在医学决定点(Xc=9.64 mmol/L)预期偏差的95%可信区间值在实验室定义的可接受偏差(4.5%)范围内,也在生物学变异的可接受偏差(5.5%)范围内。结论本室已建立并验证了血清尿素测定的酶偶联平衡参考方法;4种常用血清尿素试剂盒的测定结果与参考方法的测定结果存在差异,但误差在临床可接受范围。

Objective To establish and validate the coupled-enzyme equilibrium reference method as a reference method for urea detection and compare it with other 4 routine urea kits. Methods The reference method was verified by testing the two levels of urea in SRM909b and participating in RELA-2009.The EP9-A2 protocol was used to compare the results in forty serum samples in 4 routine kits methods with coupled-enzyme equilibrium reference method. Results The deviation of SRM909b level 1 was 2.19% and SRM 909b level 2 were 0.24% respectively through determining by the reference method.The results for RELA-2009 were within the accepted range.Comparing the confidence interval of the predicted bias with the definition acceptable error at the medical decision point Xc（Xc=9.64 mmol/L） for the 4 routine kits,the results were all within the range of defined acceptable error（4.5%） and the range of biological variation bias（5.5%）. Conclusion The coupled-enzyme equilibrium reference method for serum urea was established in our lab.The urea results measured with 4 routine kits were different from results with the reference method,but the deviation was acceptable,and it will not affect the detection results.