Introduction to Megaureter

A megaureter is a malformation of the ureter. This causes the ureter to expand, which can damage the kidneys.

What is a megaureter?

A megaureter, also known as a megaloureter, is a malformation of the ureter that is usually congenital. The deformity is possible on one side as well as on both sides of the body.

The ureter forms the anatomical structure through which urine is drained from the kidneys. The ureter also provides a connection to the urinary bladder. If a malformation leads to a narrowing (stenosis) of the ureter, this leads to a backflow of urine from the bladder, which in turn is responsible for urinary tract infections or damage to the kidneys. See AbbreviationFinder for abbreviations related to Megaureter.


A megaureter is caused by various disorders. It is important to differentiate between different types of megaureter, such as a primary and a secondary megaureter. In medicine, we speak of a primary megaureter when the enlargement of the ureter is already congenital. A secondary megaureter, on the other hand, is caused by triggers outside the ureter.

However, there are also numerous cases of a megaureter in which no specific cause such as urine reflux or a constriction can be determined. Doctors then speak of an idiopathic megaureter. The primary obstructive megaureter is caused by a constriction that forms in front of the passage to the urinary bladder. This stenosis comes about because the development of the ureter before birth was insufficient.

High urine pressure builds up above or in front of the narrowing, resulting in severe stretching of the ureter. Another sub-form is the primary refluxive megaureter. It is caused by urine refluxing from the bladder into the ureter. The causes of a secondary or acquired megaureter are different.

For example, various diseases of the urinary bladder can be responsible for a secondary obstructive megaureter, narrowing the opening of the ureter into the bladder. One reason for this is accumulation of urine, which is caused by increased wall tension in the bladder. Possible causes are disorders of the urinary bladder or the urethral valves caused by nerves.

A secondary refluxive megaureter, on the other hand, is caused by a reflux of urine, which is usually caused by obstructions or narrowings on the underside of the urinary bladder.

Symptoms, Ailments & Signs

A megaureter occurs when the diameter of the urethra increases to at least 10 millimeters. In many cases, the people affected do not feel any discomfort when the ureter is dilated. For this reason, the problem is only discovered during routine investigations.

However, some people can have symptoms. These include abnormalities or pain when urinating. Complications are rare in a megaureter. This sometimes leads to a urinary tract infection or inflammation of the kidneys, which is accompanied by fever.

In the worst case, the pathogens spread further throughout the body and cause blood poisoning (sepsis). It is also possible for the kidney cavities to expand ( hydronephrosis ), which will affect the kidney tissue in the long term. The consequences of this are limitations in kidney function or kidney failure.

Diagnosis & disease progression

A megaureter can often be identified during prenatal diagnosis. A prenatal ultrasound examination ( sonography ) in the fetus shows a disturbance in the transport of urine. Accurate and regular check-ups are necessary because the megaureter can lead to urinary tract infections or kidney damage.

Because a megaureter rarely causes symptoms, in most cases it is only noticed during routine checks. Various special procedures can be used to carry out further examinations of the ureter. These include, for example, a voiding urethrogram (MCU) or a voiding urethrogram. These methods can either disprove or confirm that urine reflux is the trigger.

Further information about the urine flow and the kidney functions can be obtained by a nuclear medical scintigraphy. A representation of the ureter is also possible with an excretory urography. During the growth of the unborn child in the womb, the megaureter often improves.

This allows the ureter to stretch, which in turn reduces dilation. In some cases, however, an operation must be carried out, which means that the patients no longer have any health problems afterwards.


In most cases, the megaureter does not cause any particular discomfort or complications. In many cases, the treatment of the disease is not initiated until late, since it is often diagnosed by chance during check-ups. In some cases, the disease can also negatively affect urination, resulting in stabbing or burning pain.

This pain has a very negative effect on the quality of life and can also lead to psychological problems or depression. It is not uncommon for the kidneys to become inflamed and fever to occur. Those affected appear exhausted and suffer from reduced resilience. Blood poisoning can also occur if the disease is not treated.

In the worst case, those affected suffer from kidney failure and die from it. Those affected are dependent on a donor kidney or on dialysis in order to survive. In most cases, the underlying disease can be treated relatively well, so that there are no special complications or restrictions. With successful treatment of the disease, there is also no reduction in the patient’s life expectancy.

When should you go to the doctor?

Since the megaureter often remains symptom-free for a long period of time, participation in preventive medical check-ups is recommended. Middle-aged children and adults in particular should take advantage of check-ups supported by statutory health insurance. This enables early detection and a treatment plan can be drawn up and applied before the onset of possible symptoms.

If the affected person experiences any peculiarities and changes while going to the toilet, a doctor’s visit should take place. If urinating causes pain, it is advisable to consult a doctor. Taking pain medication should be avoided until consultation with a doctor so that no further irregularities or complications occur. Fever, a general feeling of being unwell or inflammation of the bladder, ureters and kidneys should be discussed with a doctor. If the symptoms recur or increase in intensity, a comprehensive examination is recommended.

If left untreated, germs can spread in the organism. The person concerned is at risk of blood poisoning and thus a life-threatening condition. Therefore, a doctor should be consulted in the event of persistent symptoms or frequent recurrence of inflammatory diseases. If there is a change in the amount of urine, the color of the urine, or the smell of the urine, a doctor is needed. There is a malfunction of the kidney that requires treatment.

Treatment & Therapy

The treatment of a megaureter depends on its triggering cause. If it is a secondary megaureter, the focus is on treating the underlying disease in order to achieve improvement. If a megaureter is caused by urine reflux, conservative therapy is usually sufficient. The same applies to a narrowing of the ureter, provided there are no impairments to kidney function.

In most cases, the child’s ureter findings can already be improved in the first year of life. During this period, children are often given antibiotics to prevent urinary tract infections. If there is a pronounced constriction in the ureter that causes the megaureter, an operation is usually carried out.

Surgical intervention is necessary, especially if kidney function deteriorates. The narrowed segment of the ureter located in front of the bladder is removed, the ureter is modeled and a new connection is created between the bladder and the ureter.

Outlook & Forecast

The prognosis of the megaureter is favorable. It is a congenital malformation of the ureter, which can be changed by surgical intervention after the birth of the affected person. If there are no other disturbances in organ activity, there is a good chance of recovery. The aim of treatment is to improve the functionality of the ureter and alleviate the existing symptoms. This can be done conservatively or by administering medication.

This is intended to optimize the patient’s kidney function and reduce the risk of secondary diseases. In most cases, those affected are free of symptoms after the necessary corrective interventions. You can often recover from treatment within a few months. In addition, check-ups should be carried out afterwards so that possible changes can be reacted to immediately. However, lifelong therapy is not necessary.

However, without seeking medical treatment, life-threatening conditions can develop. Prognosis in these cases is significantly worse. The functionality of the organism is limited and organic damage develops. This limits the functioning of the kidneys and can lead to life-threatening complications. In addition, there is an increased risk of developing infections. These cause further deterioration in health.


Preventing a congenital megaureter is not possible. In order to prevent a secondary megaureter, it is advisable to have the triggering underlying diseases treated in good time.


The follow-up care for a megaureter is in many ways similar to that of a bladder infection, provided the underlying disease has not completely healed. To rule out a recurrence and/or spread of the bacteria, the patient should attend a follow-up appointment after the treatment. Follow-up care can be provided by the general practitioner or a urologist.

As a rule, a rapid urine test is carried out at regular intervals to clarify whether there is blood and/or bacteria in the urine. If this is the case, the therapy may need to be prolonged. The patient himself should take it easy and protect the kidney area from drafts. Activities that could further irritate the ureters, such as swimming, should therefore be avoided initially.

Hypothermia of the feet should also be counteracted by wearing thick socks. In addition, it is important for the patient to drink plenty of fluids afterward. This is essential for the kidneys so that they can excrete pollutants and bacteria with the urine. Urinary tract infections often need to be treated with antibiotics.

This usually not only kills the bacteria that are responsible for the urinary tract infection, but also positively minded intestinal residents that are essential for the immune system. Some patients complain of diarrhea and stomach cramps after antibiotic therapy. In this case, intestinal cleansing can help.

You can do that yourself

In many cases, a megaureter does not require treatment. A mildly pronounced malformation of the ureter usually does not cause any major symptoms and is therefore harmless. However, if symptoms such as pain when urinating or flank pain occur, this must be clarified by a doctor.

In addition to medical treatment, some measures can be taken to alleviate the symptoms. Cooling pads are a proven home remedy. Quark wraps and similar remedies can also reduce pain in the abdomen and kidneys. If you have a fever, rest and bed rest apply. In addition, a medical examination is always necessary in order to be able to identify any complications at an early stage. Surgical treatment is indicated if renal function deteriorates. The patient must then take it easy and pay attention to increased hygiene in the area of ​​the operation wound so that wound healing disorders and similar suffering do not occur. If unusual symptoms develop, a doctor must be informed.

Since a megaureter often also represents a psychological burden, the patient should consult a therapist in addition to medical treatment. In the case of chronic diseases, it is all the more important to learn how to deal with the disease and its consequences in a positive way.