Hydronephrosis is caused by a blockage in the tube that connects the kidney to the bladder (ureter). Possible causes include a kidney stone, an infection, an enlarged prostate, a blood clot, or a tumor.


Pain in the side, back, or groin and trouble urinating are some symptoms.


Treatment may include antibiotics or surgery. In severe cases, the urine may need to be drained from the bladder or kidney.

Last Updated Jun 13, 2017

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