Abstract: Thiamine is an essential water-soluble vitamin，playing a vital role in mitochondrial energy metabolism. Thiamine deficiency can affect the metabolic，nervous，cardiovascular，respiratory，gastrointestinal，and musculoskeletal systems. The causes of thiamine deficiency include primary and secondary factors. The primary cause is genetic defects in proteins involved in thiamine transport and metabolism，leading to inborn errors of thiamine metabolism known as thiamine metabolism dysfunction syndromes （THMD）. Five types have been identified，namely THMD1 to THMD5. The patients with THMD1 presents with the classic triad of diabetes mellitus，megaloblastic anemia，and sensorineural hearing loss. THMD2 to THMD5 primarily involve the nervous system. The patient’s brain MRI usually shows Leigh or Leigh-like syndrome. Early intervention with high-dose thiamine can significantly improve outcomes of the patients. THMD is often misdiagnosed and misses the optimal treatment window，ultimately resulting in death or permanent neurological sequelae. This article aims to analyze the clinical characteristics of thiamine and thiamine metabolism dysfunction syndromes and enhance vigilance against thiamine deficiency，facilitating timely interventions to reduce disability and mortality.

Key words: thiamine, thiamine metabolic dysfunction syndrome, mitochondria, leigh syndrome, hearing loss

摘要： 硫胺素是一种必需的水溶性维生素，在线粒体能量代谢中发挥重要作用。硫胺素缺乏可累及代谢、神经、心血管、呼吸、胃肠及肌肉骨骼系统，导致硫胺素缺乏的病因包括原发性和继发性。原发性硫胺素缺乏为编码硫胺素转运和代谢中相关功能蛋白的基因缺陷，导致先天性硫胺素代谢异常，引起硫胺素代谢障碍综合征（thiamine metabolism dysfunction syndrome，THMD），目前已确定5种类型，即THMD 1~5型。THMD1表现为典型的三联征，即糖尿病、巨幼细胞性贫血和感音神经性耳聋，而THMD 2~5型以神经系统损害为主，脑磁共振成像（MRI）表现为Leigh或Leigh样综合征，早期大剂量硫胺素治疗可显著改善预后。THMD常被误诊并错失治疗时机，导致死亡或永久性神经系统后遗症。文章旨在分析硫胺素及硫胺素代谢障碍综合征的临床特征，提高对硫胺素缺乏症的警觉性，以及时干预，减少致残致死。

关键词: 硫胺素, 硫胺素代谢障碍综合征, 线粒体, Leigh综合征, 耳聋