Unusual delayed onset of diabetes insipidus following closed head trauma. Case report.

A case of delayed onset of diabetes insipidus (DI), which developed 27 days after a closed head injury, is reported. The patient sustained only a minor neurological deficit and, except for antidiuretic hormone (ADH) insufficiency, hypothalamic function was intact. This selective damage of posterior pituitary function was total and permanent. Ischemia due to vascular injury may be the most likely etiology. Once the diagnosis of delayed posttraumatic DI is confirmed, the treatment of choice is DDAVP (desmopressin acetate). In contradistinction to DI immediately following minor head injury, most patients with a delayed onset of DI after trauma have permanent ADH deficiency.