[Clinical characteristics of congenital nephrogenic diabetes insipidus]

The purpose of this study was to improve the ability to visualize and diagnose congenital nephrogenic diabetes insipidus (CNDI). The clinical manifestations, laboratory examination findings, imaging features and treatment outcomes of 22 patients with CNDI admitted to the First Affiliated Hospital of Zhengzhou University from May 2013 to May 2020 were retrospectively analyzed. Among the 22 patients with CNDI, 86.4% (19 cases) were male. The age of the 22 patients ranged from 2 months to 47 years old, in which 20 cases were younger than 30 years old and 2 cases were older than 30 years old. The clinical manifestations were polydipsia and polyuria, accompanied with various degrees of fever, defects in growth and development, and increased serum creatinine in some patients. Fifteen patients (68.2%) had different degrees of bilateral kidney and ureteral hydronephrosis, and increased residual urine volume in the bladder. Pituitary magnetic resonance imaging (MRI) enhanced scan showed that the high signal intensity in the posterior pituitary lobe was not detectable in 5 cases (22.7%), and blurred in 6 cases (27.3%). Seven tested patients were all found AVPR2 gene mutation. For patients with suspected CNDI, water-inhibiting vasopressin test and genetic testing should be performed in time so as to confirm diagnosis and treat as early as possible.