Postobstructive diuresis following unilateral hydronephrosis. Case report with 58 liters per day

Increased urinary outputs are common after release of bilateral ureteral or subvesical obstruction. However polyuria is rare following unilateral obst ruction. We report a case of excessive postobstuctive diuresis of more than 58,000 mi per day (208 l in 10 days) after release of a left ureteral obst ruction in a 56-year-old female, being the highest amounts reported in the literature. Polyuria was derived from the obstructed as well as from the no rmal contralateral kidney. The involved pathomechanism is complex and not c ompletely understood. Treatment includes careful monitoring of the patient and replacement of fluid and electrolytes. In our case complete recovery of kidney function was observed after several days.