Ureterocele and Ureteral Duplication

What is a ureterocele?

A ureterocele involves the kidney, ureter, and bladder. A normal ureter is one that transports urine from the kidney to the bladder. When a child has a ureterocele, the portion of the ureter closest to the bladder becomes enlarged because the ureter opening is very tiny and obstructs urine outflow. As the urine flow is obstructed, urine backs up in the ureter tube.

What is ureteral duplication?

Children who have a ureterocele may also have an ureteral duplication. This means that they will have two ureters for one kidney that drain independently into the bladder. The ureter with the ureterocele generally drains the top half of the kidney while the duplicate may drain the lower half. The ureter with the ureterocele may enter the bladder lower than the duplicate ureter, which may cause a backflow of urine into the higher ureter.

Who is affected by ureterocele and ureteral duplication?

Ureterocele and ureteral duplication is much more common in girls than in boys. In girls, the ureterocele will nearly always involve both kidneys, whereas in boys often only one kidney is involved.

What causes ureterocele and ureteral duplication?

The cause of ureterocele and ureteral duplication is unknown; however, some cases have been reported in siblings, suggesting a genetic component.

How is a ureterocele and duplicate ureter diagnosed?

If a ureterocele is not detected on a prenatal ultrasound, it may not be detected until the child has recurrent urinary tract infections. If your child has a history of frequent urinary tract infections, your child's physician may order the following diagnostic procedures:

• Ultrasound of the entire urinary tract. A diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.

• Voiding cystourethrogram (VCUG). Your child's bladder is filled with contrast from a catheter and urination is watched to see if reflux into the ureters occurs. 

What is the treatment for a ureterocele or ureter duplication?

Treatment for ureterocele is very complex, individualized, and varies from child to child. Specific treatment for ureterocele or ureter duplication will be determined by your child's physician based on:

• Your child's age, overall health, and medical history

• The extent of the condition(s)

• Your child's tolerance for specific medications, procedures, or therapies

• Expectations for the course of the condition(s)

• Your opinion or preference

If your child is ill from a urinary tract infection, intravenous fluids and antibiotics may be administered. Once the urinary tract infection is resolved, the ureterocele will be addressed.

Treatment of the ureterocele often depends on the size of the constriction and the function of the kidney that the ureter is draining. If the area of the ureter has a great deal of urine accumulation, it may need to be surgically drained. Larger ureteroceles that may cause a great deal of reflux (or backflow) into the ureter may need to be removed. If there is a duplicate ureter, the twin may be left intact.

In some children, the kidney of the affected side may be damaged and part of it may need to be removed.

Your child may be referred to a urologist (a physician who specializes in disorders and care of the urinary tract and the male genital tract). A small ureterocele may not require medical intervention if the kidney is functioning without difficulty.