Service d'Endocrinologie et Maladies Métaboliques, CHRU de Lille, 59037 Lille Cedex, France.
Eur J Endocrinol. 2011 Oct;165(4):665-73. doi: 10.1530/EJE-11-0224. Epub 2011 Jul 13.
Gitelman syndrome (GS) is a tubulopathy caused by SLC12A3 gene mutations, which lead to hypokalaemic alkalosis, secondary hyperaldosteronism, hypomagnesaemia and hypocalciuria.
The aim of this study was to assess the prevalence of SLC12A3 gene mutations in adult hypokalaemic patients; to compare the phenotype of homozygous, heterozygous and non-mutated patients; and to determine the efficiency of treatment.
Clinical, biological and genetic data were recorded in 26 patients.
Screening for the SLC12A3 gene detected two mutations in 15 patients (six homozygous and nine compound heterozygous), one mutation in six patients and no mutation in five patients. There was no statistical difference in clinical symptoms at diagnosis between the three groups. Systolic blood pressure tended to be lower in patients with two mutations (P=0.16). Hypertension was unexpectedly detected in four patients. Five patients with two mutated alleles and two with heterozygosity had severe manifestations of GS. Significant differences were observed between the three groups in blood potassium, chloride, magnesium, supine aldosterone, 24 h urine chloride and magnesium levels and in modification of the diet in renal disease. Mean blood potassium levels increased from 2.8 ± 0.3, 3.5 ± 0.5 and 3.2 ± 0.3 before treatment to 3.2 ± 0.5, 3.7 ± 0.6 and 3.7 ± 0.3 mmol/l with treatment in groups with two (P=0.003), one and no mutated alleles respectively.
In adult patients referred for renal hypokalaemia, we confirmed the presence of mutations of the SLC12A3 gene in 80% of cases. GS was more severe in patients with two mutated alleles than in those with one or no mutated alleles. High blood pressure should not rule out the diagnosis, especially in older patients.
Gitelman 综合征（GS）是一种由 SLC12A3 基因突变引起的管状病变，导致低钾碱中毒、继发性醛固酮增多症、低镁血症和低钙尿症。
本研究旨在评估 SLC12A3 基因突变在成年低钾血症患者中的患病率；比较纯合子、杂合子和未突变患者的表型；并确定治疗效果。
记录 26 例患者的临床、生物学和遗传数据。
SLC12A3 基因筛查在 15 例患者中发现了两个突变（6 个纯合子和 9 个复合杂合子），6 例患者有一个突变，5 例患者无突变。三组患者在诊断时的临床症状无统计学差异。两组突变患者的收缩压较低（P=0.16）。令人意外的是，有 4 例患者患有高血压。5 例携带两个突变等位基因和 2 例杂合子的患者出现严重的 GS 表现。三组患者在血钾、氯、镁、卧位醛固酮、24 小时尿氯和镁水平以及肾脏病饮食调整方面存在显著差异。两组、一组和无突变等位基因组治疗前血钾分别为 2.8±0.3、3.5±0.5 和 3.2±0.3mmol/L，治疗后分别为 3.2±0.5、3.7±0.6 和 3.7±0.3mmol/L，差异有统计学意义（P=0.003）。
在因肾性低钾血症就诊的成年患者中，我们证实了 80%的病例存在 SLC12A3 基因突变。与携带一个或无突变等位基因的患者相比，携带两个突变等位基因的患者 GS 更为严重。高血压不应排除诊断，尤其是在老年患者中。
