Blockage of the Ureters

The most common cause of blockage of the ureter in children is a congenital obstruction at the point where the ureter joins the renal pelvis — the ureteropelvic junction (UPJ). This is the area at the center of the kidney where urine collects and is funneled into the ureter – tubes that carry urine from the kidneys to the bladder.

During fetal development, a baby’s kidneys first appear as buds inside the pelvis, near the bladder. As the kidneys develop, they climb gradually toward their normal position near the rib cage in the back. Sometimes, one of the kidneys fails to make the climb. It may stop after making part of the climb or remain in the pelvis. Rarely does a child have two ectopic kidneys. This problem occurs in about one in 1,500 children. 1

In UPJ obstruction, the kidney produces urine at a rate that exceeds the amount of urine able to drain out of the renal pelvis into the ureter and this causes accumulation of urine within the kidney. This accumulation is also called hydronephrosis and is easy to see on an ultrasound. This allows the physician to predict the presence of UPJ obstruction before the baby is born.

Although less common in adults, UPJ obstruction maybe caused by kidney stones, previous surgery(ies) or disorders that can cause inflammation of the upper urinary tract.

Kidney Cancer

The cause of kidney cancer isn’t clear but researchers have identified certain things that may increase your risk of developing kidney cancer. 2

  • Smoking
  • Family history of kidney cancer
  • Polycystic kidney disease (several cysts in the kidneys)
  • Chronic kidney failure and/or dialysis
  • Diet with high caloric intake or fried/sautéed meat
  • Low vitamin E intake
  • Tuberous sclerosis
  • Exposure to asbestos, blast furnaces and ovens used in iron/steel manufacturing

Diseases of the kidney are found more frequently in men than women and in racial and ethnic minority populations in the United States than in the Caucasian population. African Americans, Asian Americans, Hispanics/Latinos, and Pacific Islander Americans are three times more likely to suffer from kidney failure than Americans of European descent. 3

1.“Ectopic Kidneys”, National Urological Association Foundation,, URL:

While clinical studies support the effectiveness of the da Vinci® System when used in minimally invasive surgery, individual results may vary. Surgery with the da Vinci® Surgical System may not be appropriate for every individual. Always ask your doctor about all treatment options, as well as their risks and benefits.

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