上海地区儿童快速免疫层析法cTnⅠ参考区间的建立

Establishment of pediatric reference interval of cTnⅠ in Shanghai based on rapid immunochromatography

目的采用快速免疫层析法检测上海地区儿童末梢血心肌肌钙蛋白(cTnⅠ)水平,初步建立儿童末梢血cTnⅠ的参考区间,为临床诊断儿童心肌损伤提供实验室依据。方法选取7个月～12岁儿童240名,采用快速免疫层析法检测其末梢血cTnⅠ。先进行方法学评估(准确性、精密度、最低检测限、线性范围验证、方法比对),然后采用百分位数法确定cTnⅠ的参考区间。结果快速免疫层析法检测高、低值质控品的结果分别为4.73和0.49 ng/mL,均在质控品标示的预期范围内;低值质控品日间和日内精密度[变异系数(CV)]分别为5.97%和5.36%,高值质控品日间和日内精密度(CV)分别为6.35%和7.14%,均符合要求(CV<10%);最低检测限为0.02 ng/mL;线性范围为0.028～26.400 ng/mL;与化学发光法的相关性良好(r=0.988),检测cTnⅠ的第99百位数值为0.1 ng/mL,第99百位数值的不精密度为18.5%。采用百分位数法计算99%参考区间上限值为0.5 ng/mL,同时结合试剂说明书中标示的参考区间(<0.3 ng/mL),确定基于快速免疫层析技术的儿童末梢血cTnⅠ参考区间:<0.3 ng/mL为阴性、>0.5 ng/mL为阳性。cTnⅠ为0.3～0.5 ng/mL时需进一步检查,以判断是否有心肌损伤。结论初步建立了基于快速免疫层析法的上海地区儿童末梢血cTnⅠ的参考区间。

Objective To establish the pediatric reference interval of cardiac troponin I(cTnI)in Shanghai based on rapid immunochromatography,and to provide a reference for the clinical diagnosis of myocardial injury.Methods A total of 240 children aged from 7 months to 12 years were enrolled,and peripheral blood cTnI was determined by rapid immunochromatography.A methodology evaluation(accuracy,precision,minimum determination limit,linear range verification and method comparison)was carried out,and the reference interval of cTnI was determined by percentile method.Results The results of high-level and low-level quality control products determined by rapid immunochromatography were 4.73 and 0.49 ng/mL,respectively,which were in the expected range of quality control specification.The inter-day and intra-day precisions[coefficient of variation(CV)]for the quality control products with low level were 5.97%and 5.36%,and those with high level were 6.35%and 7.14%,respectively.They all met the requirements(CV<10%).The minimum determination limit was 0.02 ng/mL,and the linear range was 0.028-26.400 ng/mL.There was a good correlation with chemiluminescence(r=0.988).The 99th percentile of cTnI determination were 0.1 ng/mL,and the imprecision of the 99th percentile was 18.5%.The upper limit value of 99%reference interval(0.5 ng/mL)which was calculated by percentile method and the lower reference interval(<0.3 ng/mL)which was referred from reagent specification were used to establish the pediatric reference interval of serum cTnI based on rapid immunochromatography.The value of cTnI<0.3 ng/mL was negative,and the value of cTnI>0.5 ng/mL was positive.When the value of cTnI level was 0.3-0.5 ng/mL,further determination was required to perform and determine whether there was myocardial injury or not.Conclusions A rapid immunochromatography is preliminarily established for determining the reference interval of peripheral blood cTnI among children in Shanghai.