Zhou Lan, Chen Xiaohui, Xiong Jiaojiao, Lei Ling
Department of Obstetrics and Gynecology, Chongqing Health Center for Women and Children, Chongqing, China.
Department of Obstetrics and Gynecology, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
Front Pediatr. 2023 Apr 17;11:1034923. doi: 10.3389/fped.2023.1034923. eCollection 2023.
Type III Bartter syndrome (BS) is an autosomal recessive disease caused by mutations in the (chloride voltage-gated channel Kb) gene that encodes CLC-Kb. CLC-Kb is mainly located in the thick ascending limb of Henle's loop and regulates chloride efflux from tubular epithelial cells to the interstitium. Type III BS is characterized by metabolic alkalosis, renal salt wasting, hyperreninemia, and hyperaldosteronism with normal blood pressure.
We reported the case of a 3-day-old girl whose initial symptom we diagnosed as jaundice, but we accidentally found metabolic alkalosis. She showed recurrent metabolic alkalosis, hypokalemia, and hypochloremia and also had hyperreninemia and hyperaldosteronism with normal blood pressure. Both oral potassium supplements and potassium infusion therapy were unable to entirely restore the electrolyte imbalance. She was suspected of Bartter syndrome and genetic tests were performed on her and her parents. Next-generation sequencing identified gene mutation including heterozygous mutation c.1257delC (p.M421Cfs58) and a low-level mutation c.595G > T (p.E199); both mutations were also verified in the parents.
We reported the case of a classic Bartter syndrome in a newborn with a heterozygous frameshift mutation and a mosaic non-sense mutation in the gene.
III型巴特综合征（BS）是一种常染色体隐性疾病，由编码CLC-Kb的CLCNKB（氯离子电压门控通道Kb）基因突变引起。CLC-Kb主要位于髓袢升支粗段，调节氯离子从肾小管上皮细胞向间质的外流。III型BS的特征为代谢性碱中毒、肾性失盐、高肾素血症和高血压正常的高醛固酮血症。
我们报告了一名3日龄女孩的病例，其最初症状被诊断为黄疸，但我们意外发现了代谢性碱中毒。她出现反复的代谢性碱中毒、低钾血症和低氯血症，同时伴有高血压正常的高肾素血症和高醛固酮血症。口服补钾和静脉输注钾治疗均无法完全纠正电解质失衡。她被怀疑患有巴特综合征，并对她及其父母进行了基因检测。二代测序确定了CLCNKB基因突变，包括杂合突变c.1257delC（p.M421Cfs58）和低水平突变c.595G>T（p.E199）；这两种突变在其父母中也得到了验证。
我们报告了一例新生儿经典巴特综合征病例，其CLCNKB基因存在杂合移码突变和嵌合无义突变。
