What causes bilateral hydronephrosis and ureteral dilatation?

The causes of hydronephrosis and ureteral dilatation usually include congenital abnormalities, tubal obstruction, neurogenic bladder dysfunction, etc.

1. Congenital abnormalities

may exist at birth, such as narrowing of the ureteropelvic junction, renal pelvis dysplasia, etc. These abnormalities block the flow of urine, resulting in hydronephrosis and ureteral dilatation.

2. Ureteral obstruction

may occur due to stones, tumors, urethral strictures, etc. Obstruction prevents urine from exiting the kidneys, resulting in dilated renal pelvis and ureter.

3. Neurogenic bladder dysfunction

Neurogenic bladder dysfunction refers to the inability of the bladder to contract and relax normally. It may be caused by neurological diseases, spinal cord injuries, etc. When the bladder cannot urinate effectively, pressure will flow back to the kidneys, resulting in dilated renal pelvis and ureter.