The distention of the pelvis and calyces of both kidneys (see also unilateral hydronephrosis ).

Alternative Names

Hydronephrosis - bilateral

Causes, incidence, and risk factors

Bilateral hydronephrosis develops when the pelvis and calyces (urine collecting structures of the kidneys) of both kidneys become distended because urine is unable to drain from the kidney down the ureters into the bladder. Hydronephrosis is therefore not a separate disease entity; but rather a physical manifestation of the disease process that causes impairment of urine to drain out of the kidneys, ureters and bladder. Symptoms, treatment, and expected outcome are those of the associated diseases. Disorders associated with hydronephrosis include:

acute bilateral obstructive uropathy

chronic bilateral obstructive uropathy

vesicoureteric reflux

uteropelvic junction obstruction

posterior ureteral valves

neurogenic bladder

bladder outlet obstruction

prune belly syndrome

Advances in fetal ultrasound have given specialists the ability to diagnose obstructive uropathy (problems caused by the blockage of the urinary system) in the fetus before birth. Unilateral (one side only) or bilateral (both sides) obstruction of the urinary tract can be diagnosed by fetal ultrasound. Fetal conditions such as uteropelvic junction obstruction, posterior ureteral valves and prune belly syndrome can be diagnosed while the fetus is in the uterus. Newborn infants who have been previously diagnosed with obstruction while still in the uterus can receive prompt surgical correction of the defects, often with good outcomes. Experimental surgery on the fetus while in the uterus is presently being studied which can relieve the obstruction or decrease the pressure on the kidney in the fetus. Future techniques can be expected to salvage better kidney function than the good results that are presently expected.

Signs and tests

Bilateral hydronephrosis may be apparent on:

an

IVP

a

renal scan

an

ultrasound of the abdomen or kidneys

a kidney or

abdominal CT scan

Treatment

There is no separate treatment other than the treatment of the causative disorder.

Expectations (prognosis)

If obstruction is detected in the fetus, early surgical intervention shortly after birth will optimize kidney function. After surgery there is often an improvement, beyond the baseline, in renal function. Early discovery and intervention in any type of obstructive process will improve the outcome.

Complications

Renal insufficiency or renal failure may develop as a complication of many of the disorders associated with hydronephrosis .

Calling your health care provider

This disorder is usually discovered by the health care provider.

Prevention

Fetal ultrasound studies can demonstrate obstruction of the urinary tract and allow for early surgical intervention with improved outcome in the newborn. Other causes of obstruction such as kidney stones , posterior ureteral valves can be diagnosed early if individuals recognize early warning signs of obstruction and kidney disease .