A megaureter is a ureter that’s bigger than expected. It mainly affects infants and children. It doesn’t usually cause symptoms. But symptoms may include discomfort or blood in your child’s pee. Most times, providers find it during prenatal imaging tests or a child’s UTI exam. Treatment may include a “watch-and-wait” approach, antibiotics or surgery.
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The ureters are part of your urinary system. They’re two thin tubes that carry urine (pee) from your kidneys to your urinary bladder. In most people, each ureter is about 9 inches long and 1/4-inch wide. But a megaureter is an enlarged ureter. It’s greater than 3/8 of an inch wide.
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Megaureters are typically congenital (appear at birth). Healthcare providers usually discover megaureters while conducting prenatal (before birth) imaging tests. Without treatment, a serious megaureter can damage your child’s urinary system.
There are two main types of megaureters:
There are also combinations of the two main types:
Secondary megaureters are another class of megaureters. They typically develop as a result of other conditions, including:
Healthcare providers and medical researchers aren’t sure how often megaureters occur each year. But they consider megaureters a relatively rare condition that typically occurs during fetal development.
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Megaureters don’t usually cause symptoms. Healthcare providers usually find them during prenatal imaging tests. But when symptoms occur in your child, they may include:
If your child has symptoms, they may vary from others’ symptoms, including how much discomfort they may feel.
Megaureters usually occur during fetal development. As a fetus develops, the ureter usually consists of a layer of muscle tissue. But sometimes, a stiff, fibrous tissue develops in a section of the ureter instead. The fibrous tissue prevents the wavelike muscle contractions that move pee toward the bladder (peristalsis).
Megaureters can also develop if a blockage stops pee from entering the bladder. Pee starts flowing back toward the kidney, which widens the ureter. Blockages may occur when the bottom end of the ureter that connects to the bladder doesn’t develop properly (ureterocele).
Any infant or fetus can have a megaureter. However, megaureters are about four times more common in people assigned male at birth (AMAB).
Without treatment, megaureters can cause UTIs and kidney damage.
Healthcare providers typically diagnose a megaureter during a prenatal ultrasound (sonogram). Ultrasounds use high-frequency sound waves to form a picture of the fetus, including the kidney, ureter and bladder structures.
After birth, your child may have megaureter symptoms, including frequent UTIs. Your child’s pediatrician will perform a physical examination. If they suspect your child has a megaureter, they may order additional testing, including:
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Megaureter treatment depends on your child’s age, symptoms and overall health. Many children don’t require major intervention and outgrow a megaureter over time. So, your child’s healthcare provider may recommend a “watch-and-wait” approach, which may include:
If the megaureter doesn’t get better within the first year of your child’s life, increases in size (dilates), causes repeated UTIs or affects kidney function, it may require surgery. Megaureter surgical options include:
Megaureter surgery poses many of the same risks as any other operation, including:
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Rarely, there may also be a risk of damage to the areas surrounding the ureter, including blood vessels or the bladder.
If your child needs surgery to fix a megaureter, they’ll typically recover after a few weeks. A healthcare provider will give you a better idea of what to expect according to your child’s specific prognosis.
There isn’t any known way to prevent a megaureter. Healthcare providers and medical researchers need more information on a megaureter’s exact causes, including whether or not it’s genetic.
In most cases, if a prenatal imaging test reveals a megaureter, the megaureter gets better gradually without surgery. Your child will need regular imaging tests to monitor the megaureter, and they may need regular antibiotics to prevent UTIs.
If the megaureter doesn’t get better on its own, your child may need surgery.
In general, the long-term outlook for a megaureter is good. In many cases, a megaureter will improve on its own without intervention. The success rates of surgical treatments for a megaureter are high.
If your child has a megaureter, they may need regular imaging tests to evaluate their ureters and kidneys. Be sure to take your child to every appointment. If you have to cancel, be sure to reschedule.
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Go to the nearest emergency room if your child has UTI symptoms and develops:
You may want to ask your provider:
A note from Cleveland Clinic
It can be difficult and overwhelming to hear that there may be something wrong during a prenatal imaging test. But the good news is that if a healthcare provider discovers a megaureter before birth, it usually gets better without surgery. If your child needs surgery, the success rate is high. As your child grows, they may need regular imaging tests and antibiotics to prevent urinary tract infections. If you have any questions, talk to a healthcare provider.
Last reviewed on 04/04/2024.
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