Zhao Yangting, Li Kai, Chen Chongyang, Lv Xiaoyu, Wang Yawen, Ma Lihua, Fu Songbo, Liu Jingfang
The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China.
Department of Endocrinology, The First Hospital of Lanzhou University, Lanzhou, Gansu, China.
Postgrad Med. 2024 Aug;136(6):683-690. doi: 10.1080/00325481.2024.2383555. Epub 2024 Jul 23.
Nephrogenic diabetes insipidus (NDI) is a rare genetic disorder primarily associated with mutations in the arginine vasopressin receptor 2 () gene or the aquaporin 2 () gene, resulting in impaired water reabsorption in the renal tubules. This report describes a case of a young male patient with NDI from China with a history of polydipsia and polyuria for over 15 years. Laboratory examinations of the proband indicated low urine-specific gravity and osmolality. Urologic ultrasound revealed severe bilateral hydronephrosis in both kidneys, bilateral dilatation of the ureters, roughness of the bladder wall, and the formation of muscle trabeculae. The diagnosis of diabetes insipidus was confirmed by water deprivation tests. The administration of posterior pituitary hormone did not alter urine-specific gravity, and osmolality remained at a low level (<300 mOsm/kg). Based on these findings, and the genetic tests of the proband and his parents were performed. A missense mutation (c.616 G>C) in exon 3 of the gene of the proband was found, caused by the substitution of amino acid valine to leucine at position 206 [p.Val206Leu], which was a hemizygous mutation and consistent with X-chromosome recessive inheritance. The administration of oral hydrochlorothiazide improves the symptoms of polydipsia and polyuria in the proband. This novel gene mutation may be the main cause of NDI in this family, which induces a functional defect in , and leads to reduced tubular reabsorption of water.
肾性尿崩症(NDI)是一种罕见的遗传性疾病,主要与精氨酸加压素受体2(AVPR2)基因或水通道蛋白2(AQP2)基因的突变有关,导致肾小管对水的重吸收受损。本报告描述了一名来自中国的年轻男性肾性尿崩症患者,有多饮、多尿病史超过15年。先证者的实验室检查显示尿比重和尿渗透压降低。泌尿外科超声显示双肾严重双侧肾盂积水、双侧输尿管扩张、膀胱壁粗糙及肌小梁形成。禁水试验证实了尿崩症的诊断。给予垂体后叶激素后尿比重未改变,尿渗透压仍维持在低水平(<300 mOsm/kg)。基于这些发现,对先证者及其父母进行了基因检测。在先证者的AVPR2基因外显子3中发现一个错义突变(c.616 G>C),导致第206位氨基酸缬氨酸被亮氨酸替代[p.Val206Leu],这是一个半合子突变,符合X染色体隐性遗传。口服氢氯噻嗪改善了先证者的多饮、多尿症状。这种新的AVPR2基因突变可能是该家族肾性尿崩症的主要原因,它导致AVPR2功能缺陷,进而导致肾小管对水的重吸收减少。