Familial central diabetes insipidus detected by nocturnal enuresis.

A 10-year-old male referred to our clinic with the chief complaint of nocturnal enuresis also complained of daytime polyuria, frequency, and polydipsia. The clinical diagnosis was central diabetes insipidus. Since the patient's father had complained of similar symptoms, the arginine vasopressin-neurophysin II gene was examined. This revealed a single base substitution in one of two alleles in the patient, his father, and his grandfather (a C to T transition at nucleotide position 280 at codon 19 in the first exon). In conclusion, a history of polyuria or polydipsia should be carefully noted and the urinary volume and urine gravity or osmolarity examined in cases of nocturnal enuresis.