全自动荧光免疫分析仪在新生儿葡萄糖-6-磷酸脱氢酶缺乏症筛查中的应用

目的：分析全自动荧光免疫分析仪（GSP分析仪）检测新生儿葡萄糖-6-磷酸脱氢酶（G6PD）缺乏症的性能。方法：应用GSP分析仪检测国家卫生健康委临床检验中心室间质量评价质控品和G6PD试剂盒（荧光分析法）的低、高质控品，计算准确度和精密度。采用GSP分析仪和半自动荧光免疫分析仪（1420分析仪）同步检测2622例新生儿筛查标本和41例确诊患儿的标本，分析检测结果的相关性和一致性；采用GSP分析仪和1420分析仪检测漂浮和未漂浮标本各78例，比较检测结果差异；采用1420分析仪和GSP分析仪分别检测2017年1月至2018年12月1?100?384名新生儿筛查标本及2019年1月至2020年12月855?856名新生儿筛查标本，比较两种仪器的筛查效能。对目前使用的切值（26?U/dL）的合理性进行评估，并通过百分位数法，以第99.1百分位建立GSP分析仪筛查G6PD缺乏症的新切值。结果：GSP分析仪检测5个不同浓度室间质控品的检测值与靶值的相对偏倚为0.71%~4.23%，检测G6PD测定试剂盒质控品的批内精密度为4.34%~4.91%，批间精密度为0.85%~2.12%，总变异系数为5.44%~5.72%，均符合实验要求。GSP分析仪和1420分析仪检测的G6PD活性存在明显的正相关（r=0.740，P<0.01），均能筛查出41例确诊患儿，筛查的一致性较好（Kappa=0.945）。1420分析仪检测漂浮干血斑中的G6PD活性明显低于未漂浮干血斑中的G6PD活性（P<0.05），而GSP分析仪检测漂浮和未漂浮干血斑中的G6PD活性差异无统计学意义（P>0.05）。GSP分析仪和1420分析仪筛查G6PD缺乏症的敏感度均为100.00%，且特异度均在99.80%以上。与1420分析仪比较，GSP分析仪筛查G6PD缺乏症的阳性预测值、初筛阳性率和诊断率均上升，假阳性率下降（均P<0.01）。根据人群第99.1百分位建立新切值，男性为26.1?U/dL，女性为29.1?U/dL。结论：GSP分析仪检测性能良好，筛查效率高，更有利于疾病的检出，可用于临床新生儿G6PD缺乏症的大规模筛查。

Application of genetic screening processor in screening neonatal glucose-6-phosphate dehydrogenase deficiency

Objective: To evaluate the performance of genetic screening processor (GSP analyzer) in neonatal screening for glucose-6-phosphate dehydrogenase (G6PD)deficiency. Methods:The accuracy and precision of GSP analyzer was evaluated with the control materials from National Center for Clinical Laboratories and the low and high quality G6PD control kit (fluorescence analysis). GSP analyzer and semi-automatic fluorescence immunoanalyzer (1420 analyzer) were simultaneously used to detect 2622 neonatal screening samples and 41 confirmed samples to analyze the correlation and consistency of the test results; 78 floating samples and 78 non-floating samples were detected to compare the result. A total of 1?100?384 neonatal screening samples from January 2017 to December 2018 and 855?856 neonatal screening samples from January 2019 to December 2020 were detected with 1420 analyzer and GSP analyzer, respectively. Referring to the percentile method and the expert consensus, the new cut-off value of GSP analyzer for G6PD deficiency in screening was established. Results: The relative bias of GSP analyzer in detecting G6PD was 0.71%–4.23%; the intra assay precision was 4.34%–4.91%, the inter assay precision was 0.85%–2.12%, and the total coefficient of variation was 5.44%–5.72%. There was a significant positive correlation between G6PD activity detected by GSP analyzer and 1420 analyzer (r=0.740, P<0.01). Forty-one clinical confirmed patients were identified by both 1420 analyzer and GSP analyzer (Kappa=0.945). The G6PD activity in floating dry blood spots detected by 1420 analyzer was significantly lower than that in non-floating dry blood spots (P<0.05), but there was no significant difference in G6PD activity between floating and non-floating dry blood spots detected by GSP analyzer (P>0.05). The sensitivities of GSP analyzer and 1420 analyzer in screening G6PD deficiency were both 100.00%, and the specificities were both more than 99.80%. Compared with 1420 analyzer, the positive predictive value, positive rate and prevalence of G6PD deficiency detected by GSP analyzer were increased, and the false positive rate was decreased (allP<0.01). The new cut-off value was 26.1 U/dL for male and 29.1 U/dL for female according to the 99.1% percentile of the population.Conclusion: GSP analyzer has better detection performance with high automation, efficiency and throughput, which can be used in large-scale screening for neonatal G6PD deficiency.