RESUMO
CONTEXT: Central diabetes insipidus (CDI) is a rare disease during the neonatal period, making it diagnosis difficult and delaying medical treatment. CASE REPORT: We report here a case of a premature infant born at 26 weeks gestation who, during his 1st month of life, presented persistent hypernatremia with polyuria despite increased fluid supply and low sodium intake. CDI diagnosis was suspected and then confirmed by the therapeutic test with vasopressin analog, in its oral form. Electrolyte disorders were normalized after treatment, which allowed normal weight and height growth with standard fluid supply. Biological and radiological tests were all normal; this CDI was considered idiopathic. CONCLUSION: Persistent hypernatremia with excessive diuresis should alert to CDI diagnosis.
