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Urinary Reflux

(Vesicoureteral Reflux)

By

Ronald Rabinowitz

, MD, University of Rochester Medical Center;


Jimena Cubillos

, MD, University of Rochester School of Medicine and Dentistry

Last full review/revision Oct 2020| Content last modified Oct 2020
Click here for the Professional Version
Topic Resources

Urinary reflux is when urine flows backward from the bladder into the ureter and sometimes the kidney, usually because of a birth defect of the urinary tract.

A Look Inside the Urinary Tract

Organs of the Urinary Tract

Causes of Urinary Reflux

People normally have two ureters Ureters The ureters are muscular tubes—about 16 inches (40 centimeters) long—that attach at their upper end to the kidneys and at their lower end to the bladder. (See also Overview of the Urinary Tract... read more . One ureter connects the left kidney to the bladder, and the other ureter connects the right kidney to the bladder. Many birth defects of the bladder Bladder Defects There are several different birth defects that affect the bladder (the expandable, muscular sac that holds urine). Some are apparent at the doctor's examination. Others require tests to evaluate... read more or birth defects of the ureters Ureter Defects Ureters are the tubes that transport urine from the kidneys (the two organs that filter waste from the blood to make urine) to the bladder (the expandable, muscular sac that holds urine). People... read more involve the junction where a ureter connects to the bladder. Normally the junction allows urine to flow only one way, from the kidneys to the bladder. Defects of the junction can allow urine to flow back up the ureter and sometimes into the kidneys. In addition, other defects that block the flow of urine can increase the pressure in the bladder and cause urinary reflux. Reflux can affect one side or both sides.

Complications of urinary reflux

Symptoms of Urinary Reflux

Urinary reflux itself does not cause symptoms. But children may have symptoms if a urinary tract infection develops. Then children may have fever, may have pain in their abdomen or back, and may urinate more than normal or have burning when they urinate.

Diagnosis of Urinary Reflux

  • Ultrasonography

  • Sometimes voiding cystourethrography or radionuclide cystography

Doctors suspect urinary reflux if babies or young children have a urinary tract infection that is severe enough to cause fever. Usually they do ultrasonography Ultrasonography Ultrasonography uses high-frequency sound (ultrasound) waves to produce images of internal organs and other tissues. A device called a transducer converts electrical current into sound waves... read more Ultrasonography of the urinary tract to look for abnormalities.

If the ultrasonography results are abnormal or if the child keeps having urinary tract infections, doctors may do a more complicated test called voiding cystourethrography Cystography and cystourethrography There are a variety of tests that can be used in the evaluation of a suspected kidney or urinary tract disorder. (See also Overview of the Urinary Tract.) X-rays are usually not helpful in evaluating... read more . For voiding cystourethrography, a catheter is passed through the urethra into the bladder, a liquid that shows up on x-rays (contrast agent Radiopaque Contrast Agents During imaging tests, contrast agents may be used to distinguish one tissue or structure from its surroundings or to provide greater detail. Contrast agents include Radiopaque contrast agents... read more ) is put through the catheter, and x-rays are taken before and after the child urinates.

Radionuclide cystography is similar to voiding cystourethrography except that a radioactive agent is placed in the bladder and images are taken using a nuclear scanner. This test exposes the child's ovaries or testes to less radiation than voiding cystourethrography.

Treatment of Urinary Reflux

  • Sometimes preventive (prophylactic) antibiotics

  • Sometimes surgery

Treatment of urinary reflux depends on the specific birth defect and also on the severity of the complications.

Children who have few symptoms and no complications usually do not require treatment.

Children who have frequent urinary tract infections, signs of kidney damage, or both typically need treatment. If symptoms are not too severe, doctors sometimes give children daily preventive antibiotics to prevent infection. Children with more severe symptoms usually need surgery to correct the problem and ensure urine drains properly.

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