雙水平校準糾正苦味酸法肌酐檢測偏移*

牛長春，萬雅芳，李甜，廖璞

(重慶市人民醫(yī)院三院院區(qū)檢驗科/重慶市臨床檢驗中心，重慶 400014)

·臨床檢驗技術(shù)研究·

雙水平校準糾正苦味酸法肌酐檢測偏移*

牛長春，萬雅芳，李甜，廖璞

(重慶市人民醫(yī)院三院院區(qū)檢驗科/重慶市臨床檢驗中心，重慶 400014)

目的通過臨床檢驗實驗室間質(zhì)量評價(室間質(zhì)評)分析苦味酸法檢測肌酐的偏移及校準對偏移的影響。方法利用重慶市臨床檢驗室間質(zhì)評數(shù)據(jù)，開展冰凍混合人源血清(參考方法賦值)調(diào)查，分析苦味酸法與酶法肌酐檢測結(jié)果間的差異及偏移；用雙濃度水平冰凍混合人源血清(參考方法賦值)校準常規(guī)檢測系統(tǒng)后檢測室間質(zhì)控品。結(jié)果2012年至2016年重慶市苦味酸法肌酐檢測實驗室數(shù)下降；苦味酸法實驗室穩(wěn)健均值與酶法存在差異，且差值與肌酐水平有相關(guān)性(r=0.774 6)；冰凍混合人源血清(參考方法賦值)調(diào)查及國家衛(wèi)計委臨床檢驗中心正確度驗證結(jié)果均顯示，苦味酸法肌酐在低濃度存在正偏移(最大達10.39%和13.31%)，且偏移與濃度相關(guān)(r=0.988 9)，而酶法肌酐的偏移較小(最大達1.04%和1.49%)；用冰凍混合人源血清校準常規(guī)檢測系統(tǒng)后，苦味酸法肌酐檢測在低濃度的正偏移被抵消。結(jié)論苦味酸法肌酐檢測在低值范圍存在正偏移，雙濃度水平校準可糾正此偏移。

校準；雙濃度水平；肌酐；室間質(zhì)量評價

Abstract:ObjectiveTo evaluate the bias of creatinine testing by external quality assessment (EQA)and analyze the effects of calibration on the bias of tested values using Jaffe assay.MethodsThe EQA data from The Clinical Laboratory Centre of Chongqing City were utilized to investigate the frozen pooled-human serum in which the value of creatinine was determined by reference method. The differences between Jaffe assay and creatine oxidase method were analyzed and the bias was evaluated. After the routine measurement systems were calibrated using the frozen pooled-human sera with double levels, the EQA samples were tested.ResultsThe number of the laboratories using Jaffe method for creatinine measurement reduced significantly in Chongqing from 2012 to 2016. The robust average values of Jaffe assay were different from enzymatic assay significantly and the difference of the values were correlated with the concentration of creatinine (r=0.774 6). The results of the investigation using frozen pooled human serum and the trueness verification program of National Center for Clinical Laboratories indicated the positive bias of Jaffe assay was observed in low levels of creatinine with maximum of 10.39% and 13.31% and the bias correlated with the concentration of creatinine (r=0.988 9), by contrast the bias was low in enzymatic assay with maximum of 1.04% and 1.49% only. After the measurement systems were calibrated by frozen pooled human sera with double-levels, the positive bias of Jaffe assay in the low concentration of creatinine could be corrected.ConclusionThere may be a positive bias of Jaffe assay for the samples with low concentration of creatinine, which could be corrected by using the calibrators with double-levels.

Keywords: calibration; double-levels; creatinine; external quality assessment

雖然診斷腎病的新標志物，如中性粒細胞明膠酶相關(guān)脂質(zhì)運載蛋白、腎損傷分子1、半胱氨酸蛋白酶抑制劑C等[1-2]，越來越受關(guān)注，但肌酐(creatinine, Cr)作……