Ureteral obstruction

A partial or complete mechanical or functional blockage of urine flow within one or both ureters, impairing drainage from the renal pelvis to the bladder and increasing the risk of hydronephrosis and obstructive uropathy.

Causes

• Intrinsic obstruction

  • Kidney stones

  • Blood clots

  • Ureteral stricture

  • Urothelial tumor

  • Postsurgical ureteral injury

  • Endometriosis involving the ureter

• Extrinsic compression

  • Benign prostatic hyperplasia (BPH)

  • Prostate cancer

  • Colon cancer

  • Ovarian cancer

  • Cervical cancer

  • Retroperitoneal fibrosis

  • Enlarged retroperitoneal lymph nodes

  • Pregnancy

• Congenital causes

  • Ureteropelvic junction (UPJ) obstruction

  • Compression by an aberrant crossing blood vessel