青少年Gitelman综合征一例的临床表现及基因诊断分析

Clinical characteristics and SLC12A3 gene mutation profile of Gitelman syndrome： One case report

目的分析1例Gitelman综合征患者的临床特点和其SLCl2A3基因的突变特点。方法以1例拟诊断为Gitelman综合征的患者为研究对象，分析其临床表现和辅助检查结果，并行SLCl2A3基因及CLCNKB基因检测以明确诊断。结果该患者青少年起病，临床表现主要有低血钾、低血镁、低尿钙，排除长期使用噻嗪类利尿剂、泻药、慢性呕吐和腹泻可能，诊断为Gitelman综合征。分别对SLCl2A3基因和CLCNKB基因采用Sanger直接测序法，在SLCl2A3基因上检测到致病突变T304M和L488P，其中L488P被证实是本研究发现的新突变位点。结论基因检测有助于早期明确诊断Gitelman综合征并改善其预后。

Objective To describe the clinical characteristics of a patient with Gitelman syndrome, and to identify the associated SLC12A3 gene mutations. Methods A suspected case of teenager-onset Gitelman syndrome was observed in our hospital. It was further confirmed by clinical manifestations and auxiliary examination. In addition, direct sequencing for the exons of SLC12A3 gene and CLCNKB gene region was conducted to identify the probable disease-associated mutations. Results The case showed characteristics of hypokalemia, hypomagnesemia, and low level of urinary calcium and onset by age of 18. By excluding the possibilities of long-term use of thiazide diuretics, laxatives, chronic vomiting and diarrhea, he was finally diagnosed as a case of Gitelman syndrome. Furthermore, by Sanger direct sequencing, 2 coding variations were identified in SLC12A3 gene region, including T304M and L488P. IA.88P was a new heterozygous mutation. Conclusion Detection of SLCI2A3 gene mutation could facilitate the diagnosis of Gitelman syndrome and improve prognosis.