A 22-year-old male was riding a skateboard without wearing a helmet and collided with a stationary handrail at a skate park suffering blunt head trauma, brain concussion, loss of consciousness, and temporary loss of memory. During rehabilitation in the hospital, the patient began producing large volumes of urine (4.5 L/day), even after intravenous fluids had been discontinued.
The physician ordered a battery of tests, including urine osmolality.
The urine osmolality was 40 mOsm/kg water (reference interval 150-1500 mOsm/kg).
An order for plasma ADH showed a non-detectable level (<0.5 pg/mL) of the hormone.
What is a disease/disorder that could cause the above? The answer is on the next slide.
