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Cause of hydronephrosis- Kidney stone blocked ureter
Cause of hydronephrosis- Kidney stone blocked ureter

The most common causes of hydronephrosis is acute unilateral obstructive uropathy. This involves a sudden development of an obstruction in one of your ureters. They are commonly blocked by kidney stones, but scarring and blood clots can also lead to acute unilateral obstructive uropathy.