A megaureter is referred to as "big ureter" is a descriptive term not a diagnosis. The two important questions about megaureter are whether there is reflux (backwash) of urine causing the megaureter or whether there is a blockage at the ureterovesical junction causing megaureter.
If there is reflux present, the diagnosis is "refluxing megaureter" or "megaureter from reflux". If there is obstruction present, the diagnosis is "obstructed megaureter" or "primary obstructed megaureter". If there is neither reflux nor obstruction present then the diagnosis is "primary non-obstructed megaureter".
In very rare instances, there can be reflux & obstruction present and the diagnosis is "refluxing obstructed megaureter". The two most common types of megaureter by far are the "primary non-obstructed megaureter" and the "refluxing megaureter".
What are the signs and symptoms of a megaureter?
Sometimes, megaureters are found on prenatal ultrasound and are asymptomatic. However, megaureters can also be founded after a child has a urinary tract infection. Also, occasionally flank pain can be seen or there may be blood in the urine.
How is a megaureter diagnosed?
A megaureter is moreover a descriptive term which means large ureter and is diagnosed by ultrasound. Once a megaureter is found, two more tests are generally performed to see if there is reflux or obstruction.
A VCUG is performed to look for reflux. A Lasix kidney scan is conducted to look for obstruction and how well the kidneys function relative to one another.
How are megaureters treated?
Megaureters are treated differently based on their etiology. If there is reflux causing the megaureter, then it is treated with prophylactic antibiotics and occasionally endoscopic or open surgery as appropriate.
Several factors are considered at the time of recommending the treatment, if there is an obstruction or partial obstruction causing the megaureter at the ureterovesical junction.
If the kidney with the obstructed or partially obstructed megaureter has decreased function, or there are recurrent urinary tract infections, then a ureteral reimplant with the removal of the blockage is recommended.
However, if the obstructed or partially obstructed megaureter is not causing symptoms and the kidney is functioning fine, then surgery can often be avoided since the obstruction may resolve over time and the megaureter may go away.
The huge majority of these types of megaureters resolve with time and only periodic ultrasounds are performed to assess the kidney growth, if there is no obstruction and no reflux present.
Most patients with megaureter will receive prophylactic antibiotics until the megaureter goes away on its own, training related to emptying bowels with ease is given or in the cases where surgery is performed, after the surgery the training is given.
Why are megaureters treated?
Apart from the cause of megaureter (reflux or obstruction), megaureters are treated to prevent urinary tract infection and possible kidney damage.
Both reflux and obstruction can lead to kidney damage, especially in the setting of urinary tract infections. Prophylactic antibiotics may be given because of the increased risk of urinary tract infection. Surgery may be required as well.
What happens after the treatment?
For megaureters that need surgery to be performed, generally prophylactic antibiotics are continued for some time after surgery, and serial ultrasounds are performed to monitor the kidney. The surgery is very successful at relieving the obstruction.
For megaureters that do not have reflux or obstruction, they generally resolve on their own during childhood. Prophylactic antibiotics are often continued, and periodic ultrasounds are performed to monitor kidney growth and the megaureter.
Once the megaureter resolves, there is no need for further follow up or prophylactic antibiotics. Even if surgery is needed, the vast majority of children with megaureters go on to live normal lives.