Hydronephrosis is swelling of one kidney due to a backup of urine. This problem may occur in one kidney.
Hydronephrosis; Chronic hydronephrosis; Acute hydronephrosis; Urinary obstruction; Unilateral hydronephrosis; Nephrolithiasis - hydronephrosis; Kidney stone - hydronephrosis; Renal calculi - hydronephrosis; Ureteral calculi - hydronephrosis; Vesicoureteral reflux - hydronephrosis; Obstructive uropathy - hydronephrosis
Hydronephrosis (kidney swelling) occurs as the result of a disease. It is not a disease itself. Conditions that may lead to hydronephrosis include:
The blockage and swelling of the kidney may occur suddenly or may develop slowly.
Common symptoms include:
In some cases, there may be no symptoms.
Treatment depends on the cause of the kidney swelling. Treatment may include:
People who have only one kidney, who have immune system disorders such as diabetes or HIV, or who have had a transplant will need treatment right away.
People who have long-term hydronephrosis may need antibiotics to reduce the risk of UTI.
Loss of kidney function, UTI, and pain may occur if the condition is left untreated.
If hydronephrosis is not treated, the affected kidney may be permanently damaged. Kidney failure is rare if the other kidney is working normally. However, kidney failure will occur if there is only one functioning kidney. UTI and pain may also occur.
Call your health care provider if you have ongoing or severe flank pain, or fever, or if you think you may have hydronephrosis.
Prevention of the disorders that cause this condition will prevent it from occurring.
Frøkiaer J. Urinary tract obstruction. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 37.
Gallagher KM, Hughes J. Urinary tract obstruction. In: Feehally J, Floege J, Tonelli M, Johnson RJ, eds. Comprehensive Clinical Nephrology. 6th ed. Philadelphia, PA: Elsevier; 2019:chap 58.