Table of Contents
Definition of Vesicoureteral Reflux
Vesicoureteral Reflux – a condition in which URINE backflows from the BLADDER into the ureters toward the KIDNEYS. Vesicoureteral reflux may result from congenital anomalies in the structure of the ureters, such as short ureters or ureters that enter the bladder wall in an unusual location or at an unusual angle.
Normally the URETER forms a short, flattened tunnel within the bladder wall that functions like a valve to keep urine from reentering the ureter from the bladder. Structural anomalies may prevent the valvelike action of the ureter’s entrance into the bladder from functioning properly, such that when the bladder fills with urine the ureter is open and allows urine to enter.
Vesicoureteral reflux may also develop secondary to an obstruction that blocks the flow of urine from the bladder, such as bladder stones (UROLITHIASIS) or an enlarged PROSTATE GLAND in a man. Such an obstruction causes the bladder to overdistend, which causes the ureteral tunnels to open and allow urine to enter the ureters.
INFECTION that inflames and narrows the URETHRA also can obstruct the flow of urine out of the bladder. Vesicoureteral reflux presents a high risk for INFLAMMATION and bacterial infection of the kidneys (NEPHRITIS) by introducing into the kidneys BACTERIA that may be present in the urine. Vesicoureteral reflux also can cause HYDRONEPHROSIS, dilation of the renal pelvis that results from the accumulation of urine.
Nephritis and hydronephrosis both can cause permanent and sometimes progressive kidney damage.
Vesicoureteral Reflux Grading
|VESICOURETERAL REFLUX GRADING|
|Reflux Grade||Extent of Urine Reflux||Effect on Kidneys|
|grade 1||part way up URETER but not into the kidney||increased risk for NEPHRITIS|
|grade 2||completely up ureter to renal pelvis||increased risk for nephritis|
|grade 3||URINE backs up into the renal pelvis and renal calyces||mild dilation of renal pelvis and ureters|
mild nephritis likely
|grade 4||urine distends the renal pelvis and renal calyces||significant dilation of ureters|
HYDRONEPHROSIS with mild to moderate impaired renal function
risk of permanent kidney damage
|grade 5||as much or more urine refluxes as passes from the URETHRA||extensive and persistent dilation of ureters, renal pelvis, and renal calyces|
hydronephrosis with significant impaired renal function
secondary problems such as HYPERTENSION
permanent kidney damage likely
Symptoms and Diagnostic Path
The most common indication of vesicoureteral reflux is infection, the symptoms of which typically include
- flank or ABDOMINAL PAIN
- FEVER and chills
- HEMATURIA (BLOOD in the urine) or cloudy urine
- DYSURIA (discomfort with URINATION)
- urinary frequency and urinary urgency
As well, the person may strain when urinating and feel as though urine remains in the bladder (URINARY RETENTION) after urinating. The diagnostic path begins with urinalysis, which shows the presence of bacteria, leukocytes (white blood cells that fight infection), and erythrocytes (red blood cells) when there is an infection. The urologist may perform diagnostic imaging procedures, such as abdominal ULTRASOUND or COMPUTED TOMOGRAPHY (CT) SCAN, to visualize the structures of the urinary system and identify any anomalies. Radionuclide scan, INTRAVENOUS PYELOGRAM (IVP), and voiding CYSTOURETHROGRAM are additional diagnostic procedures that help the urologist assess the urinary system’s structure and function. Diagnosis of vesicoureteral reflux includes the designation of grade, which denotes the severity of the urine reflux and the effect on the kidneys.
Treatment Options and Outlook
Infection requires immediate treatment with ANTIBIOTIC MEDICATIONS. When the vesicoureteral reflux occurs secondary to an obstructive condition, treatment targets the underlying cause as well as any consequential infection. Treatment for primary vesicoureteral reflux depends on the person’s age and the grade of the reflux. Children are likely to outgrow grade 1 and grade 2 reflux when the cause is short ureters and often when the cause is unusual entry of the ureters into the bladder. Grade 3 reflux may require corrective surgery. Grade 4 and grade 5 refluxes require reconstructive surgery such as ureteroneocystostomy, in which the surgeon creates new insertion tunnels into the bladder for the ureters. Appropriate treatment reduces the risk for permanent damage to the kidneys and restores the normal flow of urine.
Risk Factors and Preventive Measures
In children the primary risk factors for vesicoureteral reflux are anomalies of structure within the urinary system; these are not preventable. In adults risk factors for vesicoureteral reflux include NEPHROLITHIASIS (kidney stones), urolithiasis, chronic URINARY TRACT INFECTION (UTI), and BENIGN PROSTATIC HYPERPLASIA (BPH) in men. Prompt and appropriate treatment for these conditions reduces the risk they will cause vesicoureteral reflux.