Abstract：
A new form of transient antenatal Bartter syndrome (aBS) was recently identified that is associated with the X-linked MAGED2 variant. Case reports demonstrate that this variant leads to severe polyhydramnios that may result in preterm birth or pregnancy loss. There is limited but promising evidence that amnioreductions may improve fetal outcomes in this rare condition. We report a woman with two affected pregnancies. In the first pregnancy, the patient was diagnosed with mild-to-moderate polyhydramnios in the second trimester that ultimately resulted in preterm labor and delivery at 25 weeks with fetal demise. Whole exome sequencing of the amniotic fluid sample resulted after the pregnancy loss and revealed a c.1337G>A MAGED2 variant that was considered diagnostically. The subsequent pregnancy was confirmed by chorionic villi sampling to also be affected by this variant. The pregnancy was managed with frequent ultrasounds and three amnioreductions that resulted in spontaneous vaginal delivery at 37 weeks and 6 days of a viable newborn with no evidence of overt electrolyte abnormalities suggesting complete resolution. A detailed review of the published cases of MAGED2-related transient aBS is provided. Our review focuses on individuals who received antenatal treatment. A total of 31 unique cases of MAGED2-related transient aBS were compiled. Amnioreduction was performed in 23 cases and in 18 cases no amnioreduction was performed. The average gestational age at delivery was significantly lower in cases without serial amnioreduction (28.7 vs. 30.71 weeks, p = 0.03). Neonatal mortality was seen in 5/18 cases without serial amnioreduction, and no mortality was observed in the cases with serial amnioreduction. In cases of second trimester severe polyhydramnios without identifiable cause, whole exome sequencing should be considered. Intensive ultrasound surveillance and serial amnioreduction is recommended for the management of MAGED2-related transient aBS.
摘要：
最近发现了一种新形式的短暂性产前巴特综合征（aBS），与X连锁MAGED2变体有关。病例报告表明，这种变异导致严重的羊水过多，可能导致早产或妊娠流产。有有限但有希望的证据表明，羊膜减少可能会改善这种罕见情况下的胎儿结局。我们报告一名妇女有两个受影响的怀孕。在第一次怀孕的时候,该患者在妊娠中期被诊断为轻度至中度羊水过多,最终导致早产和25周时分娩,胎儿死亡.羊水样品的全外显子组测序在妊娠丢失后产生,并显示c.1337G>AMAGED2变异,其被认为是诊断性的。绒毛膜绒毛取样证实了随后的妊娠也受到这种变异的影响。通过频繁的超声检查和三次羊膜减少治疗妊娠，导致在37周和6天有活力的新生儿自发阴道分娩，没有明显电解质异常的证据表明完全缓解。提供了已发表的MAGED2相关的短暂性aBS病例的详细综述。我们的审查重点是接受产前治疗的个人。共收集了31例MAGED2相关的短暂性aBS的独特病例。23例进行了羊膜切除术，18例未进行羊膜切除术。在没有连续羊膜减少的情况下，分娩时的平均胎龄显着降低（28.7vs.30.71周，p=0.03)。新生儿死亡率见于5/18例，无连续羊膜减少，在连续羊膜减少的病例中没有观察到死亡。在没有可识别原因的中期妊娠严重羊水过多的情况下，应考虑全外显子组测序.建议对MAGED2相关的短暂性aBS进行强化超声监测和连续羊膜减少。
