Symptoms associated with hydronephrosis include pain in the flank, groin or abdomen, nausea and fever says the National Kidney Foundation. Urination may be painful or incomplete, or the patient may need to urinate more frequently or feel that he needs to urinate when he doesn't. He may also become incontinent. Hydronephrosis may also be asymptomatic.
Treating the hydronephrosis depends on treating the underlying cause of it, according to the National Kidney Foundation. In severe cases, a catheter or a nephrostomy is used to drain the urine out of the kidney and prevent kidney failure. It is especially important for hydronephrosis to be treated if the patient has only one kidney, says MedlinePlus.
Many conditions can cause hydronephrosis, according to the National Kidney Foundation. They include a blood clot, tumors, pregnancy, urinary tract infections and an enlarged prostate. Kidney stones are also a cause of hydronephrosis. The tissue in the kidney also can be scarred from injury or prior surgery, and the kidney can be compromised by metastastic cancer from other organs such as the colon, prostate or cervix.
Conditions that lead to hydronephrosis are acute unilateral obstructive uropathy and a condition called vesicoureteric reflux, says MedlinePlus. The latter is when urine washes backwards from the bladder into the kidney.