一例Smith-Magenis综合征新生儿的临床特点及遗传学分析

Clinical characteristics and genetic analysis of a neonate with Smith-Magenis syndrome

目的探讨1例Smith-Magenis综合征新生儿病例的临床特征及遗传学病因。方法应用低深度全基因组测序(copy number variation sequencing,CNV-seq)技术对患儿及其父母进行遗传诊断,并分析疾病表型与遗传缺陷之间的相关性。结果患儿出生后第二天出现病理性黄疸伴免疫缺陷,头颅磁共振提示脑室增宽、枕大池扩大等。3月龄时面容表现为方脸型、前额突出、眼睛深陷、眼睑裂向上倾斜、眼距增宽、鼻梁低平等。经基因诊断结果提示患儿17p11.2区段存在约2.9 Mb杂合缺失,seq[GRCh37]del(17)(p11.2)(chr17:16836379-19880992),其父母为野生型。结论Smith-Magenis综合征多发现于儿童期及成人期病例,新生儿期病例较为罕见,Smith-Magenis综合征新生儿神经系统及行为异常特征暂时未表现,但病理性黄疸、头颅影像学异常及免疫缺陷等可能为该综合征新生儿特征,值得新生儿医师关注。

Objective To explore the clinical features and genetic etiology for a neonate with Smith-Magenis syndrome(SMS).Methods Copy number variation sequencing(CNV-seq)was applied to the neonate and his parents,and the genotype-phenotype correlation was analyzed.Results On the second day after birth,the neonate had presented with pathological jaundice and immunodeficiency.Cranial MRI revealed ventricular enlargement and enlargement of cisterna magna.At 3 months,the infant has presented with square face,prominent forehead,deep-set eyes,hypertelorism,palpebral fissure upward and button noses.Genetic testing showed that he had carried a 2.9 Mb deletion in 17p11.2 region,seq[GRCh37]del(17)(p11.2)(chr17:16836379-19880992).The same deletion was not found in either parent.Conclusion SMS is mostly diagnosed in child and adulthood,but rarely in neonates.For neonates with SMS,the neurological and behavioral abnormalities have not been shown,but pathological jaundice,CNS abnormalities and immune deficiency may be the characteristics,which require attention of neonatal physicians.