摘要目的:探讨1例微绒毛包涵体病(MVID)患儿的临床特点和遗传学病因。方法:以2019年5月至郑州大学第一附属医院就诊的1例MVID患儿为研究对象。回顾性分析其临床资料，应用全外显子组测序(WES)进行基因检测，对候选变异进行Sanger测序验证和多重连接依赖性探针扩增(MLPA)。复习文献总结MVID的临床和遗传学特点。结果:患儿为早产男婴，表现为不明原因难治性腹泻伴酸中毒，积极对症治疗，效差，于2月龄死亡。WES发现患儿携带 MYO5B基因c.1591C>T(p.R531W)杂合变异，并提示第9外显子杂合缺失。Sanger测序验证R531W变异遗传自父亲，MLPA证实第9外显子杂合缺失遗传自母亲，且为新发现的变异。国内报道7例MVID患儿中，1例失访，6例死亡；国外报道188例患者中，仅1例治愈。 结论:该MVID患儿表现为难治性腹泻伴酸中毒，预后不良。 MYO5B基因R531W和第9外显子缺失复合杂合变异可能为该患儿的致病原因，为家系遗传咨询和产前诊断提供依据。

abstractsObjective:To explore the clinical and genetic characteristics of a neonate with Microvillus inclusion disease (MVID).Methods:A neonate with MVID admitted to the First Affiliated Hospital of Zhengzhou University in May 2019 was selected as the study subject. Clinical data were collected. Whole exome sequencing (WES) was carried out, and candidate variants were verified by Sanger sequencing and multiple ligation-dependent probe amplification (MLPA). A literature was also carried out to summarize the clinical and genetic characteristics of MVID.Results:The prematurely born neonate had presented with unexplained refractory diarrhea and metabolic acidosis. Active symptomatic treatment was ineffective, and the child had died at 2 months old. WES revealed that he had harbored compound heterozygous variants of the MYO5B gene, namely c. 1591C>T (p.R531W) and deletion of exon 9. Sanger sequencing showed that the R531W variant was inherited form his father, and MLPA confirmed that the exon 9 deletion was inherited from his mother. Seven children with MVID were reported in China, of which one was lost during follow-up and six had deceased. One hundred eighty eight patients were reported worldwide and only one was cured. The clinical features of MVID had included refractory diarrhea, metabolic acidosis and poor prognosis. Conclusion:The child was diagnosed with MVID due to the compound heterozygous variants of the MYO5B gene, which has provided a basis for genetic counseling and prenatal diagnosis.