Article ID: EJ25-0431
Congenital nephrogenic diabetes insipidus (CNDI) is characterized by resistance of the distal nephrons and collecting ducts to arginine vasopressin (AVP). High doses of 1-deamino-8-D-arginine vasopressin (DDAVP), a V2-receptor-selective agonist, are effective in some cases. The present study aimed to demonstrate the use, efficacy, and safety of DDAVP and the characteristics of patients who responded to this treatment. The present, retrospective, multicentric, observational survey of patients with CNDI receiving DDAVP was based on a previous, nationwide survey conducted by the Japanese Society for Pediatric Endocrinology (JSPE) and collected data on the use (formulation, dosage, and treatment duration), efficacy (change in urine output and height SDS), and safety of DDAVP. In the initial survey, 43 of 123 JSPE council members (35.0%) observed the patients. The secondary survey of 13 patients found DDAVP to be effective in five patients (38.5%), as evidenced by a 12.6–31.6% decrease in urine output. The maximum urine osmolality on a water deprivation test and urine osmolality after vasopressin injection were lower in patients who were unresponsive to DDAVP than in those who were responsive to the drug (106 vs. 206 mOsm/H2O/kg, 140 vs. 525 mOsm/H2O/kg). The AVPR2 variants identified in the DDAVP-responsive group were p.Ala37Pro, p.Leu44Phe, p.Arg104Cys, and p.Tyr128Ser. DDAVP was effective against CNDI with residual V2R function. The water deprivation test with vasopressin injection and genetic testing may be useful for predicting responsiveness to DDAVP.