摘要目的:探讨微绒毛包涵体病（microvillus inclusion disease，MVID）的临床表现及基因变异类型。方法:回顾性分析2019年8月重庆医科大学附属儿童医院确诊的1例MVID患儿的临床特点及基因测序结果。以“微绒毛包涵体病”“先天性微绒毛萎缩”“microvillus inclusion disease”“MVID”“ MYO5B”“ STX3”“ STXBP2”为检索词分别检索中国知网、万方数据库、维普数据库及PubMed数据库自建库至2021年10月的文献，分析和总结国内外已报道的MVID的临床特征及诊断思路。 结果:（1）病例资料：患儿男性，2 d，因“发现皮肤黄染2 d”入院。该患儿表现为顽固性腹泻、间断腹胀、难以纠正的脱水、体重下降，检查提示顽固代谢性酸中毒、电解质紊乱、胆汁淤积。全外显子组测序发现患儿 MYO5B基因杂合变异c.1021C>T（p.Q341*）和c.1125G>A（p.W375*），分别遗传自患儿的父亲和母亲。患儿确诊为MVID。家属放弃治疗，患儿死亡。（2）文献复习：共获得20篇文献、共31例患儿的临床资料。结合本例（共32例）分析发现，MVID的典型临床表现主要是顽固性腹泻，同时伴有脱水、代谢性酸中毒、电解质紊乱等。部分患儿有胃肠道外症状： MYO5B基因变异者主要表现为喂养困难/营养不良（8/18）、呼吸窘迫和黄疸/胆汁淤积（均为4/18）； STX3基因变异和要表现为喂养困难/营养不良（2/5），呼吸窘迫和败血症（均为1/5）； STXBP2基因变异表现为喂养困难/营养不良（2/9），呼吸窘迫、黄疸/胆汁淤积、败血症、低血糖（均为1/9）。 MYO5B基因变异病例中，早产病例较多（8/18），其次为胎儿肠道扩张（5/18），羊水增多（5/18），父母近亲结婚、羊水胎粪污染（均为2/18）。 STX3基因变异病例中，父母近亲结婚者较多（3/5），其次为胎儿肠道扩张、羊水过多和羊水胎粪污染（各1/5）。 STXBP2基因变异病例中，父母近亲结婚者较多（3/9），其次为早产和羊水过多（各2/9）。 结论:MVID的临床表现不典型，病死率高，诊治难度高。当婴儿出现顽固性腹泻、脱水、代谢性酸中毒、电解质紊乱，或并发多种胃肠外症状时，应考虑MVID可能。 MYO5B、 STX3、 STXBP2基因变异的早期识别，可为MVID早期干预、预后判断以及遗传咨询提供依据。

abstractsObjective:To investigate the clinical features and genetic mutations of microvillus inclusion disease (MVID).Methods:Clinical features and gene sequencing results of a neonate with MVID in Children's Hospital of Chongqing Medical University in August 2019 were retrospectively analyzed. Literature was retrieved up to October 2021, with the terms of microvillus inclusion disease, congenital microvilli atrophy, MVID, MYO5B, STX3, and STXBP2 in China National Knowledge Infrastructure, Wanfang Database, VIP database, and PubMed. Clinical features, diagnosis, and treatment of the reported MVID cases were reviewed. Results:(1) Case report: A male infant presented with jaundice two days after birth and was admitted to our hospital. Clinical features included intractable diarrhea, intermittent abdominal distension, uncorrectable dehydration, and weight loss. Laboratory test results indicated metabolic acidosis, electrolyte disorder, and cholestasis. Whole exome sequencing confirmed the diagnosis of MVID in this baby boy with compound heterozygous mutations of c.1021C>T(p.Q341*) and c.1125G>A(p.W375*) in the MYO5B gene, which were inherited from the father and the mother, respectively. (2) Literature review: Except for the present case, 31 patients from 20 articles were reviewed, and the typical clinical manifestations were intractable diarrhea, accompanied by dehydration, metabolic acidosis, electrolyte disorder, etc. Some patients also developed extra-gastrointestinal symptoms, including feeding difficulties and malnutrition (8/18), respiratory distress syndrome (4/18) and jaundice/cholestasis (4/18) in patients with MYO5B mutations; feeding difficulties and malnutrition (2/5), respiratory distress syndrome (1/5), and sepsis (1/5) in patients with STX3 mutations; feeding difficulties (2/9), respiratory distress syndrome (1/9), jaundice/cholestasis (1/9), sepsis (1/9), and hypoglycemia (1/9) in patients with STXBP2 mutations. In terms of the demographic data and prenatal examination, preterm birth (8/18), fetal bowel dilatation (5/18), polyhydramnios (5/18), parental consanguinity (2/18), and meconium-stained amniotic fluid (2/18) occurred among patients with MYO5B mutations. In those with STX3 mutations, parental consanguinity (3/5), fetal bowel dilatation (1/5), polyhydramnios (1/5), and meconium-stained amniotic fluid (1/5) occurred. Of nine patients with STXBP2 mutations, parental consanguinity (3/9), preterm birth (2/9), and polyhydramnios (2/9) occurred. Conclusions:MVID has atypical clinical features and a high mortality, resulting in difficulty in the diagnosis and treatment. The possibility of MVID should be considered when an infant presents with intractable diarrhea, dehydration, metabolic acidosis, and electrolyte disorder accompanied by multiple extra-gastrointestinal symptoms. Early identification of MYO5B, STX3, and STXBP2 mutations will benefit prompt intervention, prognosis evaluation, and genetic counseling.