Overview
Definition:
Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder to the upper urinary tract
Prophylaxis in VUR aims to prevent recurrent urinary tract infections (UTIs), which can lead to renal scarring and chronic kidney disease.
Epidemiology:
VUR is a common congenital anomaly, affecting approximately 1-3% of children
It is more prevalent in infants and neonates, with higher rates in siblings of affected children and those with other genitourinary anomalies
Recurrent UTIs in VUR patients can occur in up to 30-50% of cases without prophylaxis.
Clinical Significance:
Preventing recurrent UTIs in VUR is crucial to avert long-term complications such as hypertension, proteinuria, and end-stage renal disease
Understanding evidence-based prophylaxis strategies is essential for pediatric residents preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Fever
Irritability in infants
Poor feeding
Vomiting
Abdominal pain or flank pain
Dysuria
Increased urinary frequency or urgency
Incontinence in toilet-trained children
Strong-smelling urine
Cloudy urine.
Signs:
Fever
Abdominal tenderness
Costovertebral angle tenderness
Palpable bladder distension (rare)
Failure to thrive (in recurrent cases).
Diagnostic Criteria:
Diagnosis of VUR typically involves voiding cystourethrography (VCUG) or radionuclide cystography
UTIs are diagnosed based on symptoms and urine culture with significant bacteriuria
Grading of VUR (Grades I-V) is based on radiographic appearance.
Diagnostic Approach
History Taking:
Detailed history of previous UTIs, including age at onset, number, pathogens, and treatments
Family history of VUR or renal anomalies
Fever patterns
Voiding symptoms
Bowel habits (constipation is a risk factor for UTIs).
Physical Examination:
General assessment for growth and hydration
Abdominal examination for masses or tenderness
Genital examination for abnormalities
Assessment for spinal dysraphism or other congenital anomalies.
Investigations:
Urine culture and sensitivity: Gold standard for UTI diagnosis, typically >10^5 CFU/mL for symptomatic infants and >10^6 CFU/mL for asymptomatic infants
Renal ultrasonography: Initial imaging to assess renal parenchyma, hydronephrosis, and bladder abnormalities
Voiding cystourethrography (VCUG): Essential for diagnosing VUR and determining its grade
DMSA scan: To assess for renal scarring, particularly after a febrile UTI.
Differential Diagnosis:
Other causes of febrile illness in infants and children
Anatomical abnormalities of the urinary tract not associated with VUR
Bladder dysfunction
Benign bacteriuria.
Management
Initial Management:
Prompt treatment of acute UTIs with appropriate antibiotics based on urine culture and sensitivity
Intravenous antibiotics for severe infections or infants younger than 2 months.
Medical Management:
Prophylactic antibiotic therapy: Low-dose daily antibiotics (e.g., Trimethoprim-sulfamethoxazole (TMP-SMX), Nitrofurantoin, or Cephalexin) are commonly used to prevent recurrent UTIs in children with VUR, especially those with higher grades (III-V) or recurrent infections despite optimal management
Dosing considerations are crucial and depend on age and weight
E.g., TMP-SMX 2 mg/kg/day (TMP component), Nitrofurantoin 1-2 mg/kg/day, Cephalexin 10-20 mg/kg/day.
Surgical Management:
Surgical intervention is considered for high-grade VUR (Grade V), breakthrough UTIs on prophylaxis, progressive renal scarring, or significant hydronephrosis
Procedures include ureteral reimplantation (open or endoscopic)
Indications are increasingly individualized.
Supportive Care:
Management of constipation is critical as it is associated with increased UTI risk
Parental education on hygiene, hydration, and recognizing UTI symptoms
Regular follow-up to monitor for UTIs and assess renal growth.
Complications
Early Complications:
Sepsis from UTI
Development of pyelonephritis.
Late Complications:
Renal scarring
Hypertension
Proteinuria
Chronic kidney disease
End-stage renal disease.
Prevention Strategies:
Consistent adherence to prophylactic antibiotics
Prompt diagnosis and treatment of UTIs
Surgical correction for indicated cases
Aggressive management of constipation
Regular monitoring.
Prognosis
Factors Affecting Prognosis:
Grade of VUR at diagnosis
Presence and extent of renal scarring
Recurrence of UTIs despite prophylaxis
Compliance with treatment
Presence of other comorbidities.
Outcomes:
Most children with low-grade VUR (I-II) resolve spontaneously
With effective prophylaxis and management, the risk of renal scarring and long-term complications is significantly reduced
High-grade VUR and persistent infections carry a higher risk.
Follow Up:
Regular follow-up with a pediatric nephrologist or urologist is essential
This includes periodic renal ultrasounds, VCUGs (if indicated), and monitoring for growth, blood pressure, and proteinuria
Annual review is common for children on prophylaxis.
Key Points
Exam Focus:
Antibiotic choices, doses, and duration for prophylaxis in VUR
Indications for surgery vs
medical management
Role of DMSA scan in assessing renal scarring
Management of recurrent UTIs in VUR patients
Spontaneous resolution rates based on VUR grade.
Clinical Pearls:
Always consider constipation as a contributing factor to recurrent UTIs in children with VUR
Dosing of prophylactic antibiotics is crucial
double-check weight-based calculations
The decision for surgical intervention is becoming more nuanced and less solely based on VUR grade.
Common Mistakes:
Underestimating the importance of voiding dysfunction and constipation
Inadequate duration or dosage of prophylactic antibiotics
Delaying surgical referral for high-grade VUR or breakthrough infections
Not performing adequate follow-up investigations to assess for scarring.