Abstract：
Wisconsin\'s newborn screening program implemented second-tier testing on specimens with elevated propionylcarnitine (C3) to aid in the identification of newborns with propionic and methylmalonic acidemias. The differential diagnosis for elevated C3 also includes acquired vitamin B12 deficiency, which is currently categorized as a false positive screen. The goal of this study was to summarize screening data and evaluate their effectiveness at establishing diagnoses and categorizing false positive cases. All Wisconsin newborns born between 2013 and 2019 with a positive first-tier screen for C3 were included in this study. For each case the first- and second-tier newborn screening data and confirmatory test results were compiled. The clinical determination for each case was reviewed and categorized into groups: inborn error of metabolism, maternal B12 deficiency, infant B12 deficiency, and false positive. A review of the screening data showed a significant overlap in the concentration of biomarkers for newborns with genetic versus acquired disease. Additionally, a review of confirmatory test results showed incomplete ascertainment of maternal vitamin B12 status. The Wisconsin newborn screening program recommended a confirmatory testing algorithm to aid in the diagnosis of inborn errors of metabolism and acquired vitamin B12 deficiency.
摘要：
威斯康星州的新生儿筛查计划对丙酰肉碱（C3）升高的标本进行了二级检测，以帮助鉴定患有丙酸和甲基丙二酸血症的新生儿。C3升高的鉴别诊断还包括获得性维生素B12缺乏，目前被归类为假阳性屏幕。这项研究的目的是总结筛查数据并评估其在建立诊断和分类假阳性病例方面的有效性。本研究包括2013年至2019年之间出生的所有威斯康星州新生儿，其C3一级筛查呈阳性。对于每种情况，都编制了一级和二级新生儿筛查数据和验证性测试结果。对每个病例的临床测定进行了回顾，并分为几组：先天性代谢错误，母体B12缺乏症，婴儿B12缺乏症，和假阳性。对筛查数据的审查显示，与获得性疾病相比，患有遗传性疾病的新生儿的生物标志物浓度存在显着重叠。此外,对确证试验结果的回顾显示,母体维生素B12状态的确定不完全.威斯康星州新生儿筛查计划推荐了一种验证性测试算法，以帮助诊断先天性代谢错误和获得性维生素B12缺乏症。
