Pediatric Urology

Home » Pediatric Urology » Vesicoureteral Reflux, Types, Causes, Symptoms, Diagnosis

Overview

Vesicoureteral reflux (VUR) is the backup of urine from the organ that stores urine (bladder) into the tube that carries urine from the kidney to the bladder (ureter) during urination. VUR may result in urine reflux into the renal pelvis, causing distention (hydronephrosis) and kidney damage. In children, this condition is usually caused by an abnormality that is present at birth (congenital) and is often diagnosed during prenatal ultrasound.

Types
There are two types of VUR: primary and secondary. Primary reflux is caused by a congenital (present at birth) abnormality, and secondary reflux is caused by a urinary tract infection (UTI) or an obstruction in the urinary tract.

Reflux is graded according to its severity:

• Grade I results in urine reflux into the ureter only.
• Grade II results in urine reflux into the ureter and the renal pelvis, without distention (hydronephrosis).
• Grade III results in urine reflux into the ureter and the renal pelvis, causing mild hydronephrosis.
• Grade IV results in moderate hydronephrosis.
• Grade V results in severe hydronephrosis and twisting of the ureter.

Incidence and Prevalence
VUR is diagnosed in 17–37% of prenatal ultrasounds. The condition is more prevalent in females and in children who have red hair. One-third of UTIs in children are caused by vesicoureteral reflux.

Causes and Risk Factors

Undetermined genetic risk factors may affect the development of VUR. About 34% of patients who have the condition have siblings who are also affected. Siblings of patients with VUR are routinely tested for the condition, even when symptoms are not present.

The most common cause for primary reflux in children is an abnormality in the section of the ureter that enters the bladder (called the intravesical ureter). The intravesical ureter may not be long enough to enable the ureter to close sufficiently to prevent urine reflux, or the ureter may be inserted abnormally into the bladder. This condition often resolves as the child grows and the ureter lengthens.

Other causes of primary reflux include abnormalities in detrusor muscle tissue of the bladder, abnormalities in the location of the urethral opening (e.g., hypospadias), and abnormalities in the shape of the urethral opening.

Secondary reflux is often caused by urinary tract infection (e.g., cystitis) that results in inflammation and swelling of the ureter. UTI may cause vesicoureteral reflux or vesicoureteral reflux may promote the growth of bacteria in the urinary tract, causing UTI. Secondary reflux may also be caused by urinary tract abnormalities (e.g., narrowing, or stricture, of the ureter; duplicated ureters; ureterocele) and obstructions (e.g., UPJ obstruction, stones, tumor).

Signs and Symptoms

The most common symptom of VUR is urinary tract infection (UTI). Other symptoms might include the following:

• Bedwetting (nocturnal enuresis)
• Collection of urine in the renal pelvis (hydronephrosis)
• Distention in the abdomen (caused by hydronephrosis)
• Failure to thrive
• High blood pressure (hypertension; caused by kidney damage)
• Nausea and vomiting
• Protein in the urine (proteinuria)

Complications

Untreated VUR provides access for bacteria to enter the kidneys and may result in kidney infection (pyelonephritis), kidney damage, and progressive renal failure.

Diagnosis

VUR is commonly diagnosed during infancy or childhood as a result of a urinary tract infection (UTI). UTI is diagnosed using urinalysis and urine culture. VUR that causes hydronephrosis (collection of urine in the renal pelvis) is often diagnosed during prenatal ultrasound.

A cystogram (also called cystourethrogram) and a voiding cystourethrogram (VCUG) are performed to determine if an abnormality in the urinary tract is causing reflux. In these procedures, a contrast dye is instilled into the bladder through a catheter and a series of x-rays are taken. Other diagnostic tests used to diagnose VUR include the following:

• Bladder ultrasound (to detect abnormalities that cause reflux)
• Renal ultrasound and renal scan (to evaluate hydronephrosis, kidney growth, and scarring)
• Urodynamic studies (e.g., filling cystometrogram, voiding cystometrogram)

© 1998-2009 Healthcommunities.com, Inc. All Rights Reserved.

Pediatric Urology Resources

	Join Our Pediatric Urology Issues Forum Do you have a question, want to share medical advice, or just need to discuss your situation with someone else having a similar experience? The healthchannels forum is a resource for everyone to share and discuss their health and medical needs with others.	Advertising Disclaimer
	Living with...Share your story Do you have a personal health story that you would like to share with others? As a source of free patient education, our goal is to provide our users with trustworthy information and support from others. That's why we've started our "Living with..." sections.
	Our "Living With..." support pages are a place to share experiences about living with a certain condition, disease, disorder, or illness and for loved ones of those dealing with health-related issues. Many people, especially when newly diagnosed, find comfort in knowing that others are having a similar experience. Help others by sharing your story. View stories already submitted.
	Stay Updated Sign up for our newsletter and receive important updates on the medical conditions that are most important to you.
To quickly access health information from your website's browser, download Healthcommunities.com's healthchannels toolbar.