先天性糖基化障碍Ig型一例报告并文献复习

Congenital disorder of glycosylation type I g： a case report and literature review

目的探讨先天性糖基化障碍（congenital disorders of glycosylation，CDG）Ⅰg型的临床特征及遗传学特点，提高临床对CDG-Ⅰg型的认识。 方法对上海交通大学医学院附属上海儿童医学中心收治的1例CDG-Ⅰg型患儿资料进行回顾性分析。以＂先天性糖基化障碍Ⅰg型＂、＂ALG12＂、＂先天性糖基化缺陷Ⅰg＂和＂CDG-Ⅰg＂、＂congenital disorders of glycosylation type Ⅰg＂、＂congenital disorder of glycosylation Ⅰg＂、＂ALG12＂为关键词，分别对中国知网、维普数据库和万方数据库、生物医学文献数据库（PubMed）、Web of Science数据库自建库至2018年1月收录的文献进行检索，总结CDG-Ⅰg型患儿的临床特征及遗传学特点。结果本院收治患儿男，生后1 d，因＂反应差伴低血糖＂入院，以面部畸形、肌张力减退、双乳头凹陷、阴茎短小、隐睾为主要表现。入院后因间歇性低血糖、反复感染给予抗感染、静脉补充葡萄糖及激素治疗。内分泌相关激素检查、血尿串联质谱检测结果均正常。全外显子高通量测序分析回报ALG12基因存在复合杂合突变，外显子4存在c.432C〉A（p.Cys144＊）无义突变，来自父亲，外显子7存在c.904T〉C（p.Tyr302His）错义突变，来自母亲，均为新发突变。随访患儿死亡，原因不详。文献检索目前国内尚无CDG-Ⅰg型病例报道。国外文献共收集8例CDG-Ⅰg型患儿，其中男4例，女4例，5例于新生儿期起病，主要临床表现为面部畸形、肌张力低下、生殖腺异常、凝血功能异常、免疫功能低下、反复感染、电解质紊乱等；ALG12基因突变8例，共有11个突变位点；存活6例，死亡2例。结论CDG-Ⅰg型较罕见，为常染色体隐性遗传，目前报道病例多在新生儿期起病，主要表现为多系统受累，如面部畸形、发育迟缓、肌张力减退、凝血因子减少、男性患儿性腺机能减退、低血糖等，可行ALG12基因检测明确诊断。

ObjectiveTo study the clinical features, diagnosis, genetic characteristics and treatment of congenital disorder of glycosylation type Ⅰg （CDG-Ⅰg） and to raise the awareness of CDG-Ⅰg among the clinicians.MethodThe data of one child with CDG-Ⅰg admitted to Shanghai Children′s Medical Center affiliated to Shanghai Jiaotong University School of Medicine was studied retrospectively. Literatures were retrieved with key words including ＂congenital glycosylation disorder Ⅰg＂ , ＂ALG12＂ , ＂congenital glycosylation defect Ⅰg＂ , ＂CDG-Ⅰg＂ and ＂congenital disorder＂ in the Chinese knowledge network, VP database, Wanfang database, Biomedicine, PubMed and the Web of Science database from data established until January 2018. We summarized the clinical and genetic characteristics of CDG-Ⅰg.ResultAn one-day-old male infant admitted to the Hospital due to ＂poor response with hypoglycemia＂ manifested with facial deformity, hypotonia, inverted nipples, micropenis and undescended testes. He had intermittent hypoglycemia and recurrent infection, treated with antimicrobials, glucose rehydration and hormone therapy. Serum insulin, growth hormone level, blood and urine metabolic screening were normal. The patient was compound heterozygous for ALG12 mutations, c. 432C〉A, p.Cys144＊ and c. 904T〉C, p.Tyr302His, each of his parents carried a pathogenic mutation. The patient died in follow-up for unknown reasons. No reported cases of CDG-Ⅰg from China have so far been reported yet. We reviewed the other 8 cases CDG-Ⅰg （4 males and 4 females） born in foreign countries, 5 of them with neonatal onset. Common clinical manifestaions include facial deformity, hypotonia, hypogenitalism, coagulopathy, hypoimmunity, recurrent infection, electroyte imbalance etc. The ALG12 gene has 11 mutation sites.ConclusionCDG-Ⅰg is a rare autosomal recessive disorder. Most reported patients had onset in neonatal period.It seems that the association of facial deformity, psychomotor retardation, hypotonia, coagulopathy, male hypogenitalism and hypoglycemia might be a clue to the diagnosis of CDG-Ⅰg. Gene detection of ALG12 can confirm the diagnosis. This disorder has no specific treatment yet.