Hydronephrosis occurs when urine builds up in the kidneys and cannot drain out to the bladder. This causes one or both kidneys to swell.
Two urinary system problems cause hydronephrosis:
- A blockage may prevent urine from draining out of the kidneys.
- A condition known as reflux may cause urine to flow back into the kidneys from the bladder.
These problems may in turn result from:
- A congenital blockage or defect in the urinary system
- Kidney stones
- A blood clot
- Scarring of the ureters
- A tumor in the bladder, cervix, colon or prostate
- Enlarged prostate
- Enlarged uterus during pregnancy
- Persistent urinary infection in the kidneys
- Neurogenic bladder
- Injury to structures in the urinary system, from surgery or trauma
Treatment for Hydronephrosis
Treatment involves:
- Draining excess urine from the kidney
- Removing the blockage
- Treating conditions that cause blockage or reflux
- Treating infections in the urinary system
Some causes of hydronephrosis resolve without treatment, such as pregnancy and kidney stones.
Treatment options include:
- Antibiotics to treat urinary tract infections
- Medications to reduce excess uric acid excretion
- Bladder catheter to drain the urine
- Nephrostomy — a tube in your midsection that drains urine from the kidney
- Surgery to remove a blockage or correct a defect
- Surgery to remove part or all of the kidney
Symptoms of Hydronephrosis
If symptoms occur, they may include:
- Pain in the back, waist, lower abdomen or groin
- Persistent pain with urination
- Increased urge to urinate or urinary incontinence
- Incomplete urination
- Fever
- Nausea and vomiting
- Unexplained itching
Diagnosing Swollen Kidneys
Your doctor may examine your pelvis or rectum to feel for blockages. Your doctor may also want to run these tests:
- Urine tests
- Blood tests
- Bladder catheterization
- Abdominal ultrasound
- Intravenous urogram
- Computed tomography angiography (CTA)
- MRI scan
- Cystoscopy
- Voiding cystourethrogram
Content was created using EBSCO’s Health Library. Edits to original content made by Rector and Visitors of the University of Virginia. This information is not a substitute for professional medical advice.
