Newborn Screening Quality Assurance Program, Centers for Disease Control and Prevention, 4770 Buford Highway, NE, Mail Stop F-19, Atlanta, GA 30341, United States.
Clin Chim Acta. 2011 Mar 18;412(7-8):631-5. doi: 10.1016/j.cca.2010.12.021. Epub 2010 Dec 23.
The use of tandem mass spectrometry (MS/MS) for the analysis of amino acids and acylcarnitines from dried-blood spots (DBS) has become routine practice in newborn screening laboratories. The Newborn Screening Quality Assurance Program (NSQAP) added 3-hydroxyisovalerylcarnitine (C5OH) into its routine quality control and proficiency testing (PT) DBS materials for MS/MS to assure the quality of C5OH screening. We report the results from NSQAP evaluations for C5OH-enriched DBS, and summarize participant screening practices based on their analytical methods.
NSQAP prepared C5OH-enriched DBS materials for its participants. Laboratories reported quantitative and qualitative results. Bias plots of quantitative results were constructed using reported data and the results were sorted by an analytical method.
NSQAP participants reported PT specimen 3964 as outside of normal limits for C5OH. The mean C5OH value for derivatized and non-derivatized methods was 2.80 and 2.67 μmol/l, respectively. Reported data from other specimens showed a similar trend in derivatized vs. non-derivatized assay results. Differences in C5OH quantitative values were observed among laboratories using different internal standards.
C5OH MS/MS measurements in DBS assays varied by method and the choice of internal standards. The use of NSQAP's DBS materials allows harmonization of C5OH measurements by newborn screening laboratories worldwide.
串联质谱（MS/MS）用于分析干血斑（DBS）中的氨基酸和酰基肉碱已成为新生儿筛查实验室的常规实践。新生儿筛查质量保证计划（NSQAP）将 3-羟基异戊酰肉碱（C5OH）添加到其常规质量控制和能力验证（PT）DBS 材料中，用于 MS/MS，以确保 C5OH 筛查的质量。我们报告了 NSQAP 对 C5OH 富集 DBS 的评估结果，并根据他们的分析方法总结了参与者的筛选实践。
NSQAP 为其参与者准备了 C5OH 富集的 DBS 材料。实验室报告了定量和定性结果。使用报告的数据构建了定量结果的偏差图，并按分析方法对结果进行排序。
NSQAP 参与者报告了 PT 标本 3964 的 C5OH 超出正常范围。衍生化和非衍生化方法的 C5OH 平均值分别为 2.80 和 2.67 μmol/L。其他标本的报告数据显示衍生化与非衍生化检测结果呈相似趋势。使用不同内标物的实验室之间观察到 C5OH 定量值存在差异。
DBS 测定中 C5OH 的 MS/MS 测量值因方法和内标物的选择而异。使用 NSQAP 的 DBS 材料可以使全球新生儿筛查实验室的 C5OH 测量值实现协调一致。
