Stiletto stabbing: penetrating injury to the hypothalamus with hyperacute diabetes insipidus.

Diabetes insipidus (DI) is a well documented complication observed after traumatic head injuries. We report a case of hyperacute onset DI in a 19-year-old male who sustained a hypothalamic-pituitary injury when he was stabbed in the head with a 30-cm long thin-bladed knife. At CT, our patient showed significant hemorrhagic contusions of the lower hypothalamus. He developed polydipsia, polyuria, and mild hypernatremia in the Emergency Department. Diagnostic digital subtraction angiography showed a hypervascular congestive pituitary gland with prominent draining veins. On the third day his hypernatremia became severe (183mEq/L). He was managed with parenteral fluids and a regimen of intranasal DDAVP (1-desamino 8-d-arginine vasopressin), leading to improved plasmatic sodium levels, urine output, and urinary specific gravity. In patients presenting with hyperacute posttraumatic DI, emergency room physicians and neurosurgeons should rule out direct injury to the hypothalamus and/or the posterior lobe of the pituitary, and initiate early pharmacological treatment.