Objectives: To explore early diagnostic biological markers for Leigh syndrome caused by the m.8993T>G mutation.
Methods: A retrospective analysis was performed on the clinical data of four children diagnosed with m.8993T>G mutation-related mitochondrial disease at the Children's Hospital of Chongqing Medical University from January 2014 to January 2024. Additionally, a literature review was conducted.
Results: All four children had plasma amino acid and acylcarnitine analyses that revealed decreased citrulline levels, and one child was initially identified through neonatal genetic metabolic disease screening. According to the literature review, there were 26 children with mitochondrial disease and hypocitrullinemia caused by the m.8993T>G mutation (including the four children in this study). Among these, 12 children exhibited clinical phenotypes of Leigh syndrome or Leigh-like syndrome, while 18 children were identified with hypocitrullinemia and/or elevated levels of 3-hydroxyisovalerylcarnitine (C5-OH) during neonatal genetic metabolic disease screening.
Conclusions: Hypocitrullinemia may serve as a potential biomarker for the early diagnosis of m.8993T>G mutation-associated Leigh syndrome, detectable as early as during neonatal genetic metabolic disease screening.
目的: 探索m.8993T>G变异致Leigh综合征的早期诊断生物学标志。方法: 回顾性分析2014年1月—2024年1月在重庆医科大学附属儿童医院确诊的4例m.8993T>G相关Leigh综合征患儿的临床资料并文献复习。结果: 4例患儿血氨基酸和酰基肉碱谱分析发现瓜氨酸降低，其中1例最早于新生儿遗传代谢病筛查发现。目前已报道的m.8993T>G变异合并低瓜氨酸血症的线粒体病患儿（含该研究4例）共26例，其中12例临床表型为Leigh综合征或Leigh样综合征，18例最早于新生儿遗传代谢病筛查发现存在瓜氨酸降低和/或3-羟基异戊酰肉碱（C5-OH）升高。结论: 低瓜氨酸血症可能是m.8993T>G相关Leigh综合征早期诊断的血清生物学标志物，最早可在新生儿遗传代谢病筛查中发现。.
Keywords: Child; Hypocitrullinemia; Leigh syndrome; MT-ATP6 gene; m.8993T>G.