Pediatrics: Vesicoureteral Reflux Flashcards
What is vesicoureteral reflux?
Retrograde flow of urine from the bladder to the upper urinary tract (problem at the junction of the ureter into the bladder)
What % of newborns have vesicoureteral reflux?
1%
Who is VUR most common in?
- Under 2 years of age (as we get older, risk of reflux is less)
- Femaes: 2x more than males (girls are more prone to UTI too)
What does VUR predispose to?
UTI
-In children with UTI, reflux found in 30-45%
What % of infants with antenatal detected hydronephrosis have VUR?
10-30%
What is something that might increase your suscpicion for an infant to have VUR?
Hydronephrosis detected on a prenatal US
What is the % prevalence among siblings with VUR?
35%
What % of newborns have a parent with a history of reflux?
67%
Is the inheritance pattern of VUR known?
No, the genetic loci and inheritance of is unknown
What is the competence of the ureterovesical junction (UVJ) achieved by?
A long intramural portion of the ureter which lengthens with age
What does the ureterovesical junction do?
Acts as a valve to prevent retrograde passage of urine up the ureter as the bladder fills
What happens to the ureterovesical junction during urination?
It is compressed (it should contract until the bladder is empty)
What happens to the uretervesical junction with UTI?
The area around the UVJ is inflamed and edematous
What does VUR result from?
Incompetent closure of the UVJ
What are the 2 cateogires of VUR?
- Primary reflux
2. Secondary reflux
What is primary reflux to do?
Failure of the anti-reflux mechanisn
What is secondary reflux to do?
Other anatomic deformities
- Posterior uretheral valves
- Neurogenic bladder: It doesn’t contract and function properly (there is a lack of coordinated contraction)
- Duplication of upper urinary tract
What does an increased grade of VUR correspond to?
Worse reflux
What does grade 1 VUR involve?
Ureter only
What does grade 2 VUR involve?
Ureter, pelvic, and calyces
Is there dilation of the ureter in grade 2 VUR?
No
What is seen in grade 3 VUR?
- Mild dilation of the ureter and/or pelvic
- No blunting of fornices
What is seen in grade 4 VUR?
- Moderate dilation of the ureter, pelvis, and calyces
- Maintains papillary impression
What is seen in grade 5 VUR?
Gross dilation and loss of papillary impression (this is very severe)
What 2 things are associated with VUR?
- Recurrent UTI
2. Acute pyelonephritis
What can acute pyelonephritis lead to in children?
- Renal scarring
2. End stage renal failure (ESRF)
What are 5 methods of diagnosing VUR?
- Visualization of urinary backflow and associated scarring
- Prenatal US
- Postnatal US
- Voiding cystourethrogram (VCUG)
- Dimercaptosuccinic acid (DMSA) renal scan
What is associated with severe degree of reflux?
Visualization of urinary backflow and associated scarring
What tests can raise suspicion for VUR and how?
Pre and post natal US…if you see hydronephrosis, could be a sign of VUR
What is the gold standard for diagnosing VUR?
Voiding cystourethrogram
Once diagnosis of VUR is made, what test can be done for follow up depending on severity?
DMSA (nuclear scan)
What can a VCUG do for you?
- You can see the anatomy of the renal tract
2. You can grade the severity of the reflux
What are the complications of VUR?
- Renal scarring
2. Complications during pregnancy
What are some problems that renal scarring can cause?
- Proteinuria
- HTN
- Renal failure
What % of patients with VUR have spontaneous resolution at 2 years?
51%
What are the associated factors with spontaneous resolution?
- Age of diagnosis under 1 year of age
- Lower grades of VUR
- Prenatal hydronephrosis
- Unilateral involvement
What is the rate of spontaneous resolution in grade 1 VUR?
72%
What is the rate of spontaneous resolution in grade 2 VUR?
61%
What is the rate of spontaneous resolution in grade 3 VUR?
49%
What is the rate of spontaneous resolution in grade 4 VUR?
32%
What is the rate of spontaneous resolution in grade 5 VUR?
It’s rare
What are treatment considerations with VUR?
- Prompt treatment of UTI
2. UTI prophylaxis when appropriate
What must be part of the initial evaluation with VUR?
- Renal status: Urinalysis, serum creatinine, renal US
- Growth parameters: Worry that the child won’t grow on target for age and gender
- BP
Why is VUR considered a RF for recurrent pyelonephritis and possible renal scarring?
Because conclusive evidence demonstrating whether or not directed therapeutic interventions towards VUR affect long-term renal outcome is lacking
What is the decision of observation, medical, or surgical intervention based on?
- Risk of reflux to the patient
- Likelihood of spontaneous resolution
- Parental-patient preferences
Which grades of VUR are at greatest risk and require treatment?
3-5
What are the 2 categories for treatment of grade 3-5 VUR?
- Antibiotic prophylaxis
- Surgery
* Between these 2 there is no statistical difference in outcome
What are the 3 circumstances when surgical treatment of VUR is required?
- Grade V reflux with scarring
- Grade V reflux in children over 6 years of age
- Children who fail medical therapy
What grades of VUR are lower risk and treated case by case?
1-2
How are grades 1-2 VUR treated?
Medical monitorying versus antibiotic
What 2 drugs are given as antibiotic prophylaxis for VUR?
- TMP-SMX (Bactrim)
- Nitrofurantoin
* One daily dose at half the therapeutic dose
Does Bactrim require refridgeration?
NO
What happens in an open surgical repair and what is the success rate?
- You reimplant the ureter (flipping ureter and sew it back in….it’s very invasive)
- Greater than 95%
What is the endoscopic correction of VUR called?
Subureteric transurethral injection (STING procedure)
How does STING work?
You inject bulking agents (dextranomer/hyaluronic acid (Dx/HA or DEFLUX)) via cystoscopy into bladder wall beneath the ureteral orifice to elongate the intramural section of the ureter
What are the rates of successful correction and long-term outcomes for STING?
- Rate of successful correction isn’t as high as with the open procedure
- Long-term outcome of the endoscopic approach is uncertain
What are complications associated with STING?
There is a low risk of complications… the risk of ureteral obstruction after ET of VUR is less than 0.5%
What are 3 reasons antibiotic prophylaxis for VUR is desirable?
- Prevents UTI
- Minimize risk of pyelonephritis
- Noninvasive
What are 6 reasons antibiotic prophylaxis for VUR is undesirable?
- Long-term: Until VUR resolves (years)
- Inconvenient
- Side Effects: Nausea, vomiting, skin rash, rare anapylaxis, and systemic effects
- Compliance
- Antibiotic resistance
- Breakthrough infections
Why are surgical considerations desirable?
They prevent renal damage (one this is established, it can’t be reversed)
Why are surgical considerations undesirable?
The value of surgical correction in a self-limiting condition…?
What are 4 follow up considerations for patients with VUR?
- Growth parameters
- Blood pressure
- Urine culture with any UTI symptoms
- Annual renal US
When do you discontinue medical therapy?
There is no conclusive evidence, but reasonable:
- Resolution on VCUG to grade 1
- Infection free for 6-9 months
- Toilet trained
