Congenital nephrogenic diabetes insipidus in a baby girl

A 6-week-old girl with fever, hypernatraemia, dehydration, and polyuria failed to concentrate urine in response to exogenous vasopressin administration. There was no family history of nephrogenic diabetes insipidus. When she was 15 months old, the infusion of vasopressin did not produce an increase in urinary cyclic-AMP.