Vesicoureteral Reflux in Chile: Symptoms, Causes & Treatment | aihealz
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Vesicoureteral Reflux.Care & specialists in Chile
In Chile, vesicoureteral Reflux is managed by nephrologists. Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder up the ureter and sometimes into the kidney, predisposing to febrile urinary tract infections, pyelonephritis, and renal scarring. Primary VUR is present in roughly 1-3% of healthy children and is found in 30-40% of children evaluated after a first febrile UTI.
aliases · Vesicoureteral Reflux (VUR — urine backflow from bladder to kidney)· Reflujo vesicoureteral· Reflux vésico-urétéral· वेसिकोयूरेटेरल रिफ्लक्स· reviewed May 14, 2026
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Reviewed by AIHealz Medical Editorial Board · NephrologyLast reviewed May 13, 2026
Vesicoureteral reflux (ICD-10: N13.70 unspecified, N13.71 without reflux nephropathy, N13.72 with reflux nephropathy without hydroureter, N13.73 with reflux nephropathy with hydroureter) is the retrograde flow of urine from the bladder into one or both ureters and possibly into the renal pelvis and intrarenal collecting system. Primary VUR is caused by a deficient ureterovesical junction (short submucosal ureteric tunnel, abnormal angle of insertion) that fails to provide a competent flap-valve mechanism during bladder filling and voiding. Secondary VUR is the consequence of elevated bladder pressure or distal obstruction, including posterior urethral valves, neurogenic bladder, dysfunctional voiding, and severe bladder outlet obstruction. The International Reflux Study Committee grades VUR I to V based on the voiding cystourethrogram appearance: grade I (reflux into ureter only), II (reflux up to renal pelvis without dilatation), III (mild ureteric and pelvic dilatation), IV (moderate dilatation with blunting of fornices), and V (severe dilatation with tortuous ureter and loss of papillary impressions).
key facts
Prevalence
Approximately 1-3% of healthy children; 30-40% of children with first febrile UTI have detectable VUR (AAP, AUA)
Demographics
Female-to-male ratio approximately 2-3:1 overall; boys present earlier (infancy) and have higher rates of secondary VUR from posterior urethral valves; girls predominate at presentation after first UTI
Avg. age
Most diagnoses made between 1-5 years of age after a febrile UTI; prenatal hydronephrosis detected on routine ultrasound prompts diagnosis at birth in some cases
Global cases
Tens of thousands of new pediatric diagnoses annually in the US; substantially under-diagnosed in low- and middle-income countries
Specialist
Nephrology
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How you might notice it
The key symptoms of Vesicoureteral Reflux are: Febrile urinary tract infection in an infant or young child, often with fever above 38.5°C, irritability, poor feeding, and vomiting; UTI is the typical presentation of previously undiagnosed VUR., Recurrent febrile UTIs (two or more episodes), often with the same or different organisms; pattern raises suspicion for VUR even before imaging., Pyelonephritis with flank pain, costovertebral tenderness, fever, and pyuria in an older child or adolescent., Dysfunctional voiding symptoms: urgency, frequency, urinary incontinence (daytime wetting), constipation, holding maneuvers, and incomplete bladder emptying., Failure to thrive, poor weight gain, or unexplained anemia in an infant with recurrent UTIs and reflux., Hypertension in older children or adolescents with established reflux nephropathy and renal scarring., Proteinuria detected on routine urinalysis in an older child with prior pyelonephritis or known reflux nephropathy..
01Febrile urinary tract infection in an infant or young child, often with fever above 38.5°C, irritability, poor feeding, and vomiting; UTI is the typical presentation of previously undiagnosed VUR.
02Recurrent febrile UTIs (two or more episodes), often with the same or different organisms; pattern raises suspicion for VUR even before imaging.
03Pyelonephritis with flank pain, costovertebral tenderness, fever, and pyuria in an older child or adolescent.
Diagnosis is initiated by clinical suspicion (febrile UTI, recurrent UTIs, prenatal hydronephrosis, family history, or dysfunctional voiding) and confirmed with imaging. The standard imaging pathway combines renal and bladder ultrasound with voiding cystourethrogram (VCUG), the gold-standard test for grading VUR. Ultrasound assesses for hydronephrosis, ureteric dilatation, bladder wall thickening, post-void residual, and other anatomical issues; it can suggest but cannot exclude VUR. VCUG fills the bladder with iodinated contrast through a urethral catheter and obtains fluoroscopic images during filling and voiding, grading reflux I-V by the International Reflux Study Committee. Radionuclide cystography (RNC) is a lower-radiation alternative used for follow-up after diagnosis but less anatomical detail than VCUG. Contrast-enhanced voiding ultrasound is gaining adoption as a radiation-free alternative in some centers. 99m-Tc DMSA renal scintigraphy detects renal parenchymal scarring (reflux nephropathy) and acute pyelonephritis with high sensitivity; it is recommended at baseline in high-grade VUR and after febrile UTIs. Functional bladder evaluation with non-invasive uroflowmetry and post-void residual addresses bladder-bowel dysfunction; formal urodynamics is reserved for neurogenic bladder and complex cases. Laboratory workup includes urinalysis, urine culture during UTI, complete blood count, renal function, and blood pressure measurement. Imaging follow-up depends on grade, age, and clinical course; spontaneous resolution is documented by repeat VCUG every 12-24 months until reflux resolves or surgical intervention is selected.
Key tests
01
Renal and bladder ultrasoundScreens for hydronephrosis, ureteric dilatation, bladder anomalies, and renal scarring; initial imaging after first febrile UTI in children 2-24 months
02
Voiding cystourethrogram (VCUG)Gold-standard diagnosis and grading of VUR; visualizes urethra and bladder anatomy
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Treatment & cost
medical treatments
✓Active surveillance and bladder-bowel optimization
✓Continuous antibiotic prophylaxis (TMP-SMX 2 mg/kg/day or nitrofurantoin 1-2 mg/kg/day)
✓Treatment of underlying cause (PUV ablation, neurogenic bladder management)
✓Treatment of acute UTI and pyelonephritis
surgical options
Endoscopic injection of bulking agent (Deflux — dextranomer/hyaluronic acid)Resolution of reflux 70-85% after one injection; 90% after two injections; lower success rates in higher grades (IV-V)
Open ureteric reimplantation (Cohen, Politano-Leadbetter, Lich-Gregoir)Resolution of reflux in 95-98% in modern series across grades; preferred for grade IV-V VUR and persistent or recurrent disease
Laparoscopic and robotic ureteric reimplantation (extravesical and intravesical)Resolution of reflux 92-98% in published series; reduces hospitalization and recovery time compared with open
Ureteric reimplantation with augmentation cystoplasty (neurogenic bladder)Resolution of reflux 85-95% with concomitant control of high bladder pressure; long-term metabolic and mechanical issues with intestinal segments require monitoring
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Causes & risk factors
known causes
Primary congenital defect of the ureterovesical junction
Short or absent submucosal tunnel of the distal ureter as it passes obliquely through the bladder wall, producing an incompetent flap valve mechanism. The normal 4-5 mm tunnel functions as a one-way valve during bladder filling and voiding; shorter tunnels allow retrograde flow.
Posterior urethral valves (boys)
Congenital obstructing membrane in the posterior urethra of male infants causing bladder outlet obstruction, secondary VUR, and bilateral hydroureteronephrosis. Most severe cause of secondary VUR in infancy. Requires prompt cystoscopic valve ablation.
Neurogenic bladder
Bladder dysfunction from spinal dysraphism (myelomeningocele, tethered cord, sacral agenesis) or other neurological disease produces high storage pressure that overcomes ureterovesical junction competence. Causes secondary VUR in 30-50% of affected children.
Dysfunctional voiding and bladder-bowel dysfunction
Functional bladder and bowel disorders (urgency, frequency, withholding behavior, constipation, encopresis) elevate bladder pressure and impair complete emptying, contributing to or unmasking secondary VUR. Treatment of constipation and dysfunctional voiding often resolves the reflux.
Genetic factors
VUR shows clear familial aggregation. Siblings of index cases have 25-50% prevalence and offspring 30-65%. Several candidate genes (PAX2, ROBO2, RET) are implicated in the embryonic development of the ureterovesical junction, but no single high-penetrance gene accounts for most cases.
Bladder outlet obstruction or instrumentation
Severe phimosis, urethral stricture, prior surgical instrumentation, and chronic indwelling catheter can produce secondary VUR. Each is potentially correctable.
risk factors
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Living with it
01Recognize and treat constipation early in toddlers and young children; constipation is a major contributor to bladder-bowel dysfunction and recurrent UTI.
02Teach scheduled voiding every 2-3 hours during toilet training; double voiding (urinating twice) helps empty the bladder completely.
03Maintain adequate hydration with age-appropriate fluid intake throughout the day.
04Address dysfunctional voiding habits (urgency, frequency, holding maneuvers) with behavioral therapy or biofeedback.
05Investigate febrile UTIs in young children with renal and bladder ultrasound; VCUG is added selectively per AAP and AUA guidelines.
06Consider screening siblings of children with high-grade VUR, especially those under 3 years of age.
recommended foods
•Adequate fluid intake distributed throughout the day (age-appropriate)
•High-fiber diet with whole grains, fruits, and vegetables to prevent constipation
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When to seek help
why see a nephrology
Pediatric urology and pediatric nephrology jointly manage VUR. Pediatric urologists evaluate anatomy, perform endoscopic injection and reimplantation surgery, and manage posterior urethral valves and neurogenic bladder. Pediatric nephrologists assess renal function, hypertension, and proteinuria, and manage children with reflux nephropathy and chronic kidney disease. Referral to a pediatric center is recommended for grade IV-V VUR, breakthrough UTIs, renal scarring, and complex secondary VUR.
01Reflux nephropathy (renal cortical scarring) in 10-30% of children with high-grade VUR — detected by DMSA scan and prevented by prompt UTI treatment and prophylaxis or surgery when indicated.
02Hypertension developing during childhood and adulthood in 10-30% of those with bilateral scarring — monitor blood pressure annually.
03Chronic kidney disease and progression to end-stage renal disease — accounts for 7-17% of pediatric ESRD; lifelong renal function monitoring is essential.
04Proteinuria and focal segmental glomerulosclerosis in adolescents and young adults with significant reflux nephropathy.
05Pregnancy complications including pyelonephritis, hypertension, and preterm birth in women with prior VUR and renal scarring.
Primary VUR (developmental)Caused by a short or absent submucosal ureteric tunnel at the ureterovesical junction, allowing retrograde flow during bladder filling and voiding. Most common form (>70% of cases). Hereditary contribution: 25-50% of siblings of an affected index child have VUR.
Secondary VUR (from elevated bladder pressure or obstruction)Result of detrusor overactivity, neurogenic bladder, dysfunctional elimination syndrome, posterior urethral valves, or bladder outlet obstruction. Treatment requires correction of the underlying cause; reflux often resolves once normal bladder dynamics are restored.
Reflux nephropathyRenal parenchymal scarring associated with VUR, recurrent pyelonephritis, and high-grade reflux during early childhood. Detected by 99m-Tc DMSA scintigraphy; manifests later as hypertension, proteinuria, and chronic kidney disease in some patients.
Sibling VUR (asymptomatic)Reflux detected in siblings of an index case during screening. 25-50% of siblings have some grade of VUR, often low-grade and self-resolving. The 2010 AUA guideline updated 2017 leaves routine sibling screening to clinician discretion.
Prenatal/postnatal hydronephrosis with VURPrenatal hydronephrosis detected on routine maternal ultrasound prompts postnatal evaluation. VUR is found in 10-40% of these infants; many have spontaneous resolution but high-grade postnatal hydronephrosis warrants further imaging.
Grade by VCUGGrades I to V based on extent of contrast reflux on voiding cystourethrogram, from reflux into the ureter only (I) to severe dilatation with tortuous ureter (V). Higher grades have lower spontaneous resolution rates and higher renal scarring risk.
Living with Vesicoureteral Reflux
Timeline
Acute UTI resolves over 7-14 days with appropriate antibiotics. Bladder-bowel dysfunction therapy yields measurable improvement over 3-6 months. Spontaneous resolution of low-grade VUR typically over 12-60 months. Endoscopic injection: bladder catheter rarely needed; return to normal activity within 24-48 hours. Open ureteric reimplantation: hospital stay 1-3 days, full recovery 4-6 weeks. Long-term monitoring with annual to biennial imaging and renal function testing for at least 5-10 years.
Lifestyle
01Adhere to scheduled voiding (every 2-3 hours) and complete bladder emptying techniques (double voiding, relaxed sitting).
02Treat constipation aggressively with osmotic laxatives, fiber, and adequate fluid intake.
03Take prescribed antibiotic prophylaxis once daily at the same time, without skipping doses.
04Maintain good perineal hygiene (front-to-back wiping in girls) and avoid bubble baths and harsh soaps.
05Report any febrile illness to the medical team; submit urine culture before starting empirical antibiotics when possible.
06Attend scheduled follow-up imaging and renal function appointments.
Daily management
01Take prophylactic antibiotic once daily at the same time, after dinner or before bedtime.
Complementary approaches
Behavioral and timed voiding programsStructured toilet training with timed voiding every 2-3 hours, complete bladder emptying technique, biofeedback for dysfunctional voiding, and constipation management. First-line non-pharmacological intervention.
Pelvic floor and bladder retraining therapyPediatric physical therapy with biofeedback for dysfunctional voiding and urinary incontinence. Particularly useful for older children with bladder-bowel dysfunction contributing to reflux.
Choosing a doctor
Choose a pediatric urology center with experience in endoscopic injection (Deflux), open and minimally invasive reimplantation, and management of neurogenic bladder. Combined pediatric urology and nephrology programs offer integrated long-term care. Confirm availability of nuclear medicine (DMSA) and contrast-enhanced voiding ultrasound where preferred.
Vesicoureteral reflux (VUR) is the backward flow of urine from the bladder up the ureter and sometimes into the kidney. It predisposes to kidney infections and renal scarring. About 1-3% of healthy children have VUR, and 30-40% of children with a first febrile urinary tract infection are found to have it.
How is vesicoureteral reflux diagnosed?▾▴
Diagnosis is made with a voiding cystourethrogram (VCUG), in which contrast is instilled into the bladder through a urethral catheter and X-rays are taken during filling and voiding. Renal and bladder ultrasound is the initial screening test, and DMSA scintigraphy detects renal scarring.
What are the grades of VUR?▾▴
VUR is graded I to V by the International Reflux Study Committee. Grade I is reflux into the ureter only; grade II up to the renal pelvis without dilatation; grade III mild dilatation; grade IV moderate dilatation with blunting of fornices; grade V severe dilatation with tortuous ureter and loss of papillary impressions.
Will my child outgrow VUR?▾▴
Most children outgrow low-grade VUR. Spontaneous resolution occurs in approximately 80% of grade I, 60% of grade II, 40% of grade III, and 20% of grade IV within 5 years. Higher grades and bilateral disease are less likely to resolve spontaneously and may require intervention.
What is the treatment for VUR?▾▴
Treatment is individualized by grade, age, scarring, and recurrent UTI history. Options include active surveillance with bladder-bowel optimization, continuous antibiotic prophylaxis, endoscopic Deflux injection (70-85% success), or open or minimally invasive ureteric reimplantation (95-98% success).
Are antibiotics required for VUR?▾▴
Continuous antibiotic prophylaxis (TMP-SMX or nitrofurantoin) is offered selectively for high-grade VUR, recurrent febrile UTI, or bladder-bowel dysfunction. The RIVUR trial showed a 50% reduction in febrile UTI recurrence over 2 years. Not all children with VUR require prophylaxis; decisions are individualized.
What is Deflux?▾▴
Deflux is dextranomer/hyaluronic acid copolymer, a bulking agent injected cystoscopically into the submucosa beneath the ureteric orifice to lengthen the submucosal tunnel and restore the flap-valve mechanism. It is an outpatient procedure with success rates of 70-85% after one injection and 90% after two.
When is surgery needed for VUR?▾▴
Ureteric reimplantation is offered for high-grade VUR (IV-V), breakthrough febrile UTIs despite prophylaxis, persistent VUR with renal scarring, severe bladder-bowel dysfunction not amenable to medical therapy, and patient or family preference for definitive correction. Success rates exceed 95%.
What is reflux nephropathy?▾▴
Reflux nephropathy is renal cortical scarring caused by VUR and recurrent pyelonephritis. It develops in 10-30% of children with high-grade VUR and can progress to hypertension, proteinuria, and chronic kidney disease. DMSA scintigraphy is the most sensitive test for scarring.
Does VUR run in families?▾▴
Yes. Siblings of an affected child have 25-50% prevalence of VUR, and offspring have 30-65% prevalence. The 2017 AUA update considers but does not require sibling screening; many centers obtain renal ultrasound on younger siblings, especially those under 3 years.
Can VUR cause kidney failure?▾▴
Reflux nephropathy accounts for 7-17% of pediatric end-stage renal disease and a smaller proportion of adult dialysis cases. Most children with VUR have excellent long-term renal function; those at risk are those with bilateral scarring, persistent high-grade reflux, and recurrent untreated pyelonephritis.
What is bladder-bowel dysfunction?▾▴
Bladder-bowel dysfunction is the combination of dysfunctional voiding (urgency, frequency, holding behavior, incomplete emptying) and constipation. It is strongly linked to recurrent UTI and persistent VUR. Treatment of constipation and scheduled voiding training alone resolves a substantial proportion of low-grade reflux.
Is VUR found before birth?▾▴
Prenatal hydronephrosis (urinary tract dilatation) detected on routine fetal ultrasound prompts postnatal evaluation. VUR is found in 10-40% of these infants. Persistent or severe postnatal hydronephrosis warrants VCUG; mild cases are often monitored with serial ultrasound only.
What is the RIVUR trial?▾▴
The Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial published in the NEJM 2014 randomized 607 children with grade I-IV VUR after a first or second febrile UTI to TMP-SMX prophylaxis or placebo. Prophylaxis reduced febrile UTI recurrence by 50% (12% vs 25% over 2 years).
Do all children with febrile UTI need a VCUG?▾▴
No. The 2011 AAP guideline recommends renal and bladder ultrasound after a first febrile UTI in children 2-24 months. VCUG is added when ultrasound is abnormal, when a second febrile UTI occurs, or when atypical features are present (poor response, unusual organism, family history).
Can children with VUR play sports?▾▴
Yes. Most children with VUR participate in normal age-appropriate sports and physical activities. After endoscopic injection, normal activity resumes within 1-2 days. After open reimplantation, contact sports are typically restricted for 4-6 weeks to allow surgical site healing.
Should women with prior VUR be monitored during pregnancy?▾▴
Yes. Women with prior VUR, especially those with renal scarring, have higher rates of pyelonephritis, hypertension, and preterm birth during pregnancy. Pre-pregnancy counseling, close obstetric and renal follow-up, and consideration of low-dose antibiotic prophylaxis in selected cases are recommended.
Is VCUG painful for children?▾▴
VCUG involves placement of a urethral catheter, which causes brief discomfort and anxiety. Topical anesthetic gel, calm preparation, presence of a parent, and sometimes mild sedation reduce distress. Most children tolerate the test well, and child-life specialists often help with preparation and coping at major centers.
What are posterior urethral valves?▾▴
Posterior urethral valves are a congenital obstructing membrane in the posterior urethra of male infants causing bladder outlet obstruction, secondary VUR, and bilateral hydroureteronephrosis. They are a leading cause of severe pediatric chronic kidney disease and require prompt cystoscopic valve ablation.
How often does my child need follow-up?▾▴
Follow-up typically includes renal and bladder ultrasound every 12-24 months and VCUG every 12-24 months until reflux resolves or surgery is performed. DMSA scintigraphy is repeated after febrile UTIs and at baseline for high-grade VUR. Blood pressure and urinalysis are checked at every visit.
When should I see a pediatric urologist?▾▴
Refer to pediatric urology for grade IV-V VUR, recurrent or breakthrough febrile UTIs despite prophylaxis, renal scarring on DMSA, posterior urethral valves or other anatomical anomalies, persistent reflux beyond age 5-6, and any case where surgery or endoscopic intervention is being considered.
Urinalysis and urine cultureDiagnoses urinary tract infection and identifies organism for targeted antibiotic therapy
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Bladder function assessment (uroflowmetry, post-void residual)Identifies bladder-bowel dysfunction contributing to reflux and recurrent infection
Outlook
Most children with low-grade VUR (I-III) without renal scarring have an excellent long-term prognosis. Spontaneous resolution occurs in 80% of grade I, 60% of grade II, and 40% of grade III within 5 years; resolution is less common in higher grades and bilateral disease. Endoscopic injection and ureteric reimplantation each have high success rates (70-85% and 95-98% respectively) in achieving anatomical correction. Long-term renal outcomes depend on the presence of renal scarring at diagnosis and on prevention of recurrent pyelonephritis: children without scarring have normal long-term renal function in over 95%, while those with bilateral scarring have a 10-20% risk of progressive chronic kidney disease, hypertension, or proteinuria by adulthood. Reflux nephropathy accounts for 7-17% of pediatric end-stage renal disease and a small but meaningful share of adult dialysis. Hypertension develops in 10-30% of those with bilateral scarring during long-term follow-up. Pregnancy in women with prior VUR and renal scarring carries higher risks of pyelonephritis, hypertension, and preterm birth and warrants pre-pregnancy counseling and close obstetric monitoring.
Family history of VUR or reflux nephropathygenetic
Siblings of an affected index child have 25-50% prevalence; offspring have 30-65% prevalence. The 2017 AUA update considers but does not mandate sibling screening; many centers obtain renal ultrasound on younger siblings.
Female sexnon-modifiable
Female-to-male ratio approximately 2-3:1 at presentation, partly reflecting higher rates of UTI as the presenting event. Boys are diagnosed earlier (infancy) and have higher rates of secondary VUR from PUV.
30-40% of children with a first febrile UTI have detectable VUR on VCUG. The AAP 2011 guideline recommends ultrasound after the first febrile UTI in children 2-24 months and VCUG only in those with abnormal ultrasound or recurrent UTI.
Strongly associated with VUR persistence and recurrent UTI. Treatment of constipation and dysfunctional voiding alone resolves a substantial proportion of low-grade reflux.
Prenatal hydronephrosisnon-modifiable
10-40% of children with prenatal hydronephrosis have postnatal VUR. Persistent or severe postnatal hydronephrosis prompts VCUG; mild cases are often serially monitored with ultrasound.
Posterior urethral valves (boys)non-modifiable
Major cause of severe secondary VUR in male infants; requires endoscopic valve ablation followed by long-term urology and nephrology follow-up.
Race and ethnicitynon-modifiable
Higher prevalence of VUR identified in White children compared with Black children in US cohorts; lower in some African and Asian populations. The reason is incompletely understood.
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Adequate calcium and vitamin D for normal growth
•Probiotic-rich foods (yogurt, kefir) may modestly reduce UTI recurrence
foods to avoid
•Excessive caffeinated beverages (sodas, energy drinks) that irritate the bladder
•Constipating foods (excess dairy in some children, processed snacks)
•Bladder irritants (acidic juices, spicy foods) when symptomatic
•Skipping meals or restricting fluids out of fear of incontinence
06
Antibiotic resistance, gastrointestinal effects, and allergic reactions from prolonged prophylaxis; weighed against UTI prevention benefit.
choosing the right hospital
01Pediatric urology service with endoscopic injection and open/minimally invasive reimplantation capability
02Pediatric nephrology service for long-term renal follow-up
03Pediatric radiology with VCUG, RNC, and DMSA expertise
04Bladder-bowel dysfunction clinic with biofeedback and behavioral therapy
05Multidisciplinary spina bifida and neurogenic bladder program
Essential facilities
Children's hospitals with pediatric urology departmentsPediatric nephrology programsPediatric continence and bladder-bowel dysfunction clinicsMultidisciplinary spina bifida centersPediatric kidney transplant programs for end-stage reflux nephropathy
02Schedule bathroom visits every 2-3 hours during the day; do not hold urine for prolonged periods.
03Use double voiding technique (urinate, wait 1-2 minutes, urinate again) to empty the bladder completely.
04Treat constipation daily with prescribed laxatives, fiber, and adequate fluid intake; aim for a soft, well-formed stool daily.
05Maintain a UTI symptom diary noting fever, dysuria, urgency, abdominal pain, or new wetting.
06Submit urine culture during any febrile illness; do not start antibiotics empirically without communicating with the urology team.
Exercise
Normal age-appropriate physical activity is encouraged. Children with VUR participate fully in sports. After ureteric reimplantation, contact sports are typically restricted for 4-6 weeks to allow healing. After endoscopic injection, normal activity can resume within 24-48 hours.