Bilateral hydronephrosis is the enlargement (distention) of the pelvis and urine collecting structures of both kidneys. Bilateral means both sides.

See also: Unilateral hydronephrosis

Bilateral hydronephrosis oocurs when urine is unable to drain from the kidney down the ureters into the bladder. Hydronephrosis is not itself a disease, but rather a physical result of whatever disease is keeping urine from draining out of the kidneys, ureters, and bladder.

Disorders associated with bilateral 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

Signs of hydronephrosis is generally seen during pregnancy ultrasound studies and as such there are no symptoms in the fetus.

In the newborn, any diagnosed urinary tract infection is reason to suspect some type of obstructive problem in the kidney. In the older child, repeat urinary tract infections are cause for evaluation of possible obstruction.

Unfortunately, with the exception of an increased number of urinary tract infections, obstruction of the urinary tract is often without symptoms.

Bilateral hydronephrosis may be seen on:

• CT scan of the abdomen or kidneys
• IVP
• Pregnancy (fetal) ultrasound
• Renal scan
• Ultrasound of the abdomen or kidneys

Placing a Foley catheter may relieve the obstruction. Other treatment options include draining the bladder or relieving pressure through percutaneous nephrostomy tubes. Once the blockage is treated, attention must be paid to treat the underlying cause (such as an enlarged prostate).

Advances in fetal ultrasound have given specialists the ability to diagnose problems caused by bilateral obstruction of the urinary tract in the developing fetus. If an obstruction is detected in a fetus, surgery shortly after birth will improve kidney function.

Newborns who have been previously diagnosed with obstruction while still in the uterus can receive prompt surgical correction of the defects, often with good results.

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

This disorder is usually discovered by the health care provider.

A fetal ultrasound can reveal an obstruction of the urinary tract and allow for early surgery with better outcomes in the newborn. Other causes of obstruction, such as kidney stones, can be diagnosed early if individuals recognize early warning signs of obstruction and kidney disease.