新生儿22q11.2缺失综合征5例临床及基因分析

目的 分析22q11.2缺失综合征(22q11.2 deletion syndrome, 22q11.2DS)的临床和基因特征，提高对新生儿期发病22q11.2DS的认识。方法 选择2018年2月-2021年10月新乡医学院第一附属医院新生儿科和中南大学湘雅二医院新生儿专科收治的22q11.2DS患儿，对其临床表现、诊断及基因检测结果等进行回顾性分析。结果 5例22q11.2DS新生儿患儿中男性3例，女性2例。早产儿2例，剖宫产4例。床旁胸片或超声发现胸腺小或缺如4例，术中发现胸腺缺如1例。4例有先天性心脏病(法洛四联征2例，室间隔缺损合并房间隔缺损2例)。感染不易控制2例，反复低钙血症2例。基因检测结果为新生变异4例，遗传自母亲1例；缺失片段大于2.45Mb的3例，缺失片段3.0Mb左右的2例。结论 新生儿期22q11.2DS主要表现为先天性心脏病和胸腺小或缺如，对怀疑该病的新生儿尽早行基因检测明确诊断，以指导进一步治疗。

Clinical and genetic analysis on 5 cases with neonatal 22q11.2 deletion syndrome

Objective To analyze the clinical and genetic characteristics of 22q11.2 deletion syndrome (22q11.2DS). Methods The 22q11.2DS children admitted by the Department of Neonatology of the First Affiliated Hospital of Xinxiang Medical University and Division of Neonatology of the Second Xiangya Hospital of Central South University from February 2018 to October 2021 were selected, and their clinical manifestations, diagnosis and genetic testing results were retrospectively analyzed. Results There were 5 cases of 22q11.2DS neonates, 3 male cases and 2 female cases, 2 cases of premature babies and 4 cases of cesarean sections. Undersized or absent thymus was found in 4 cases by bedside chest radiography or ultrasonic examination, and one absent thymus was found during operation. Four cases were found to have congenital heart disease (2 cases with fallot's tetralogy, 2 cases with ventricular septal defect combined with atrial septal defect). There were 2 cases with intractable infection and 2 cases with recurrent hypocalcemia. The genetic testing results showed that there were 4 cases with novel variation, 1 case with maternal inheritance, 3 cases with absent fragment greater than 2.45 Mb and 2 cases with absent fragment in about 3.0 Mb. Conclusion The 22q11.2DS in the neonatal period are mainly manifested as congenital heart disease and undersized or absent thymus. The newborn suspected of 22q11.2DS should be diagnosed by genetic testing to the earliest convenience to guide further therapy.