LC-MS/MSmethod for the differential diagnosis of treatable early onset inherited metabolic epilepsies
LC-MS/MSmethod for the differential diagnosis of treatable early onset inherited metabolic epilepsies
复制标题
DOI：
10.1002/jimd.12244
复制
发表时间：
2020-09-01
影响因子：
4.2
通讯作者：
Hersberger, Martin
中科院分区：
文献类型：
--
作者：
Mathis, Deborah;Beese, Karin;Hersberger, Martin
快速诊断和早期特异性治疗代谢性癫痫由于先天代谢错误（IEMs）是至关重要的，以避免不可逆转的后遗症。目前，除了氨基酸和有机酸的谱分析外，还使用了一系列额外的靶向分析来选择性筛选这些疾病。这种策略可能导致较长的周转时间、重复采样和诊断延迟。为了取代这些个体靶向分析，我们开发了一种新的液相色谱-质谱法（LC-MS/MS），用于鉴别诊断遗传性代谢性癫痫。该方法可同时定量12种代谢物(磺胺半胱氨酸、胍丁酯、肌酸、胡椒果酸、Delta(1)-哌啶-6-羧酸酯（P6C）、脯氨酸、Delta（1)-吡啶-5-羧酸酯（P5C）和b -6-维生素），用于诊断9种不同的可治疗的以早发性癫痫为主的IEMs。血浆和尿液样品与内标混合，沉淀，上清采用LC-MS/MS分析。与以前的分析相比，不需要对代谢物进行衍生化分析。除P6C和P5C外，该LC-MS方法可用于所有代谢物的定量结果，由于缺乏市售标准，P6C和P5C只能获得半定量结果。所有分析物的变异系数均低于15%，回收率在80% ~ 120%之间。对已知IEMs患者样本的分析证明了该方法的诊断价值。所提出的检测方法涵盖了选定的生化标记，提高了实验室的效率，并可能导致更快的诊断和早期治疗，避免对IEMs患者造成不可逆的损害。
Rapid diagnosis and early specific treatment of metabolic epilepsies due to inborn errors of metabolism (IEMs) is crucial to avoid irreversible sequalae. Nowadays, besides the profile analysis of amino- and organic acids, a range of additional targeted assays is used for the selective screening of those diseases. This strategy can lead to long turn-around times, repeated sampling and diagnostic delays. To replace those individual targeted assays, we developed a new liquid chromatography mass spectrometry method (LC-MS/MS) for the differential diagnosis of inherited metabolic epilepsies that are potentially treatable. The method was developed to simultaneously quantify 12 metabolites (sulfocysteine, guanidinoacetate, creatine, pipecolic acid, Delta(1)-piperideine-6-carboxylate (P6C), proline, Delta(1)-pyrroline-5-carboxylate (P5C), and the B-6-vitamers) enabling the diagnosis of nine different treatable IEMs presenting primarily with early-onset epilepsy. Plasma and urine samples were mixed with internal standards, precipitated and the supernatants were analyzed by LC-MS/MS. In comparison with previous assays, no derivatization of the metabolites is necessary for analysis. This LC-MS method was validated for quantitative results for all metabolites except P6C and P5C for which semiquantitative results were obtained due to the absence of commercially available standards. Coefficients of variation for all analytes were below 15% and recovery rates range between 80% and 120%. Analysis of patient samples with known IEMs demonstrated the diagnostic value of the method. The presented assay covers a selected panel of biochemical markers, improves the efficiency in the laboratory, and potentially leads to faster diagnoses and earlier treatment avoiding irreversible damage in patients affected with IEMs.