Abstract：
Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is an autosomal recessive disease associated with the mutation of the TYMP gene. MNGIE causes gastrointestinal and neurological symptoms, and the gastrointestinal symptoms are usually notable, which may lead to misdiagnosis. However, we herein report a 29-year-old female who presented with prominent neurological symptoms, while her gastrointestinal symptoms were mild. Brain MRI revealed prominent diffused leukoencephalopathy and peripheral neuropathy was confirmed by the nerve conduction velocity test. Biochemical tests showed elevated plasma thymidine, deoxyuridine, and lactate levels. Molecular genetic testing demonstrated a novel homozygous TYMP c. 447 dupG mutation and the patient\'s mother was heterozygous for the mutation but had no clinical features. MNGIE was diagnosed based on the results. Unlike other patients who had notable gastrointestinal symptoms, this patient presented with more prominent neurological symptoms than gastrointestinal symptoms, which might have been caused by the novel mutation in the TYMP gene.
摘要：
线粒体神经胃肠脑病（MNGIE）是一种与TYMP基因突变相关的常染色体隐性遗传疾病。MNGIE会引起胃肠道和神经症状，胃肠道症状通常很明显，这可能会导致误诊。然而,我们在此报告了一名29岁的女性，她表现出突出的神经症状，而她的胃肠道症状很轻微.脑部MRI显示突出的弥漫性白质脑病，神经传导速度测试证实了周围神经病变。生化测试显示血浆胸苷升高，脱氧尿苷,和乳酸水平。分子遗传学检测显示了一种新的纯合TYMPc。447dupG突变，患者的母亲是该突变的杂合，但没有临床特征。根据结果诊断出MNGIE。与其他有明显胃肠道症状的患者不同，这个病人表现出比胃肠道症状更突出的神经症状,这可能是由TYMP基因的新突变引起的。
