Fatal hyponatremia in a 7-year-old girl with cloacal exstrophy after cystoscopy for a bladder stone.

A case of fatal hyponatremia in a 7-year-old girl following a percutaneous cystolithotomy is presented. Stone removal by percutaneous cystolithotomy is considered a safe and effective procedure, but this may depend on the type of solution used for irrigation. In this case less than 2L of sterile water was used as irrigation in an augmented bladder causing a drop in sodium to 120 mmol/L in 30 min. The result was a massive shift of water into the cerebral tissue, cerebral edema and death.