Three patients, 11, 17 and 41 days old with various degrees of central nervous system (CNS) lesions developed central diabetes insipidus as a complication of hypothalamic damage. Two of the children had congenital CNS malformations including meningomyelocele, hydrocephalus, and prosencephaly, while the third child presented Streptococcus agalactiae meningitis, complicated with CNS hemorrhage and hypertensive dilatation of the lateral ventricles. All of them fulfilled the criteria for central diabetes insipidus, reaching high levels of serum sodium and osmolality, along with hypotonic urine. The responses to intranasal arginine-vasopressin were prompt, normalizing the serum levels of sodium and increasing urinary osmolality, allowing a better metabolic balance, avoiding continuing damage to the already compromised CNS. The neonatologist must be aware of the possibility of this kind of complication even in a normal child with CNS infection. Imaging studies showing hemorrhage in the region of the posterior hypothalamus must be a sign that this type of complication is able to occur.