上海地区丙氨酸氨基转移酶测定标准化探讨

Evaluation of the standardization for the determination of alanine aminotransferase in Shanghai

目的通过使用统一校准品的可比性调查实验，评价丙氨酸氨基转移酶（ALT）标准化工作在上海市二级甲等以上医院实施的可行性。方法上海地区72家二级甲等以上医院检验科参加ALT检测结果可比性调查实验（共3次）。方法一：采用日立-罗氏检测系统，将具有溯源性的国际临床化学协会（IFCC）推荐方法的ALT定值传递的混合人血清样本作为实验用临时校准品校准各实验室检测系统后，测定发放的血清调查品。方法二：与临时校准品同时发放1份非人血清基质的冻干品，由实验室用各自的检测仪器、试剂和发放的已定值的血清临时校准品为冻干品定值。用该冻干品作为校准品（各实验室的定值会不同），并与各自的检测仪器和试剂组成自建检测系统测定发放的血清调查品。同时，在本实验室选择4家试剂（分别为CZ、FH、KH、WK），在日立自动生化分析仪上用2种方法校准后，分别选择40份患者样本与罗氏试剂进行实验室内部比对实验。结果对参加调查医院的全部检测系统第3次实验结果统计，用统一校准品校准前，血清调查品均值为42．3、63．3和137．8U／L，其变异系数（CV）分别为14．9％、12．5％和10．4％；血清临时校准品校准后，血清调查品均值为44．5、67．1和146．8U／L，其CV分别为4．9％、2．6％和3．3％；自建检测系统实验的血清调查品均值分别为44．3、67．2和146．3U／L，其CV分别为5．3％、5．2％和4．3％。结论血清临时校准品实验基本达到设定的实验目标，即美国临床实验室修正法规（CLIA＇88）允许范围的1／5～1／4（CV在4％～5％），自建检测系统实验结果比用统一校准品校准前的离散度减小约1／2。通过加强人员培训、控制实验环节等一系列方法，进一步缩小ALT检测结果的差异，实现ALT检测结果在上海地区的一致和可比是可行的。

Objective To evaluate the standardization for the determination of alanine aminotransferase （ALT） using same calibrator in Shanghai. Methods Investigations of the coincidence of the result for ALT determination in laboratories of 72 third and second grade hospitals in Shanghai were made 3 times. The first method, in HITACHI chemis- try analyzer and the reagents of Roche diagnostics assigned value of International Federation of Clinical Chemistry and Laboratory Medicine（IFCC） method transferred from Roche cfas to human serum pool as temporary calibrator. The analytical systems of laboratories calibrated with temporary calibrator used for the determination of survey＇s samples. The second method（self-buih analytical system） , in analytical systems of laboratories assigned value transferred from temporary calibrator to the lyophilized material. Then the values of lyophilized material were used to calibrate self-built analytical system for the determination of survey＇s samples again. After performing the two methods, in our laboratory 40 patient specimens were evaluated comparatively using ALT reagents form four manufacturers （CZ, FH, KH, WK） and Roche diagnostics with HITACHI chemistry analyzer. Results Results from all laboratories were calculated. Before using same calibrator, means of samples were 42.3,63.3 and 137.8 U/L; coefficients of variation（CV） were 14.9% , 12.5% and 10.4% , respectively. After using temporary calibrator, means of samples were 44.5,67.1 and 146.8 U/L; CV were 4.9%, 2.6% and 3.3%, respectively. After using lyophilized material, means of samples were 44.3, 67.2 and 146.3 U/L; CV were 5.3%, 5.2 % and 4.3%, respectively. Conclusions After using the temporary calibrator, CV is less than 1/5-1/4 of CLIA requirements for analytical quality（CV from 4% to 5%） and achieves expectant goals. After using lyophilized material, CV is less than before about 1/2. We believe that the standardization for ALT determination with same calibrator in Shanghai should be carryied out by all-around training and strong control.