A NOVEL INTRAGENIC DELETION RELATED TO THE ARGININE VASOPRESSIN V2 RECEPTOR CAUSES NEPHROGENIC DIABETES INSIPIDUS

Abstract

Background

Nephrogenic diabetes insipidus (NDI) is a disease characterized by a defective response to the antidiuretic hormone (ADH) of the renal collecting duct leading to a decline in the ability of the pro-urine concentration.

Case presentation

A 23-year-old man presented with an over 20-year history of polyuria concomitant with hydronephrosis. The diagnosis of NDI was established by gene analysis as well as a water-deprivation and vasopressin test. All exons of arginine vasopressin V2 receptor (AVPR2) gene were amplified and sequenced. A novel hemizygous intragenic inframe deletion, cDNA 255 ^th bp to 263 ^th bp in exon 2 of AVPR2, was identified. These relevant translations from the 85 ^th amino acid Asp to 88 ^th amino acid Val were missed and replaced by amino acid Glu. After treating the patient with hydrochlorothiazide, his symptoms improved significantly.

Conclusion

The genetic analysis revealed a novel X-linked intragenic inframe deletion, AVPR2 gene cDNA 255 ^th bp to 263 ^th bp, causing NDI.