Abstract: A retrospective analysis was conducted on the case data of a child with congenital disorder of glycosylation caused by PMM2 gene mutation admitted to Beijing Jingdu Children's Hospital on May 11， 2020 due to liver damage， in order to understand the clinical phenotype and characteristics of congenital disorder of glycosylation caused by PMM2 gene mutation. Through literature review， the clinical and genetic characteristics of congenital disorders of glycosylation  mainly involving the liver were summarized. The results showed that the child was an 8-month-old female infant with onset of liver damage and myocardial damage， accompanied by coagulation dysfunction， hypoglycemia， hypoalbuminemia， thyroid dysfunction， abdominal fluid accumulation， and developmental delay. Physical examination showed signs of inverted nipples and esotropia. Head MRI suggested possible cerebellar dysplasia and Dandy Walker malformation. Gene analysis showed PMM2 compound heterozygous mutations c.448-2A>G （splicing）， c.712C>G （p.R238G）. After symptomatic treatment of liver protection， plasma and human albumin infusion， the child's abnormal laboratory test indicators improved significantly. Long-term follow-up showed significant mental and motor developmental delay. Based on the literature search， it is found that there are two main types of congenital disorders of glycosylation  with liver involvement. One type is mainly liver involvement， including MPI-CDG， TMEM199-CDG， CCDC115-CDG， ATP6AP1-CDG， SLC37A4-CDG， and VMA21-CDG. The other type is mainly other system involvement combined with liver damage， including PMM2-CDG， ALG-CDG， PGM1-CDG， and COG-CDG. Liver damage is mainly manifested as liver enlargement， elevated transaminase levels， abnormal coagulation function，and hepatic fibrosis， etc.， and a few can cause liver failure. Therefore， it can be concluded that congenital disorders of glycosylation has diverse clinical manifestations and can involve multiple systems， with liver damage being a common clinical manifestation.

Key words: child, congenital disorders of glycosyl-ation, liver, gene

摘要： 对2020-05-11北京京都儿童医院1例因肝损害入院的由PMM2基因突变所致的先天性糖基化障碍患儿病例资料进行回顾性分析，以了解PMM2基因突变的先天性糖基化障碍的临床表型及特点。通过文献复习，总结以肝脏受累为主的先天性糖基化障碍的临床特征及遗传学特点。结果发现，患儿为8月龄女婴，以肝损害、心肌损害起病，伴有凝血功能异常、低血糖、低蛋白血症、甲状腺功能异常、腹腔积液及发育落后，查体有乳头内陷、内斜视等体征，头颅MRI提示小脑发育不良、Dandy-Walker畸形可能，基因显示PMM2复合杂合突变c.448-2A>G（splicing），c.712C>G（p.R238G），经对症保肝、输注血浆及人血白蛋白等治疗患儿异常实验室检查指标明显好转，长期随访有明显精神及运动发育落后。结合检索的文献发现，可引起肝脏受累的先天性糖基化障碍主要分两种，一类是以肝脏受累为主，主要有MPI-CDG、TMEM199-CDG、CCDC115-CDG、ATP6AP1-CDG、SLC37A4-CDG和VMA21-CDG;另一类是其他系统受累为主合并肝损害，常见的有PMM2-CDG、ALG-CDG、PGM1-CDG及COG-CDG等。肝损害主要表现为肝大、转氨酶升高、凝血功能异常、肝纤维化等，少数可引起肝衰竭。由此得出，先天性糖基化临床表现多样，可累及多系统，肝损害是常见的临床表现。

关键词: 儿童, 先天性糖基化障碍, 肝脏, 基因