Best

1. Approach to Hydronephrosis
in children
Prepared by: Dr. Bisrat K.(GSRIII)
Moderator: Dr. Abreham (Assistant professor of Pediatric surgery)
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2. Contents
• Objectives
• Introduction
• Antenatal Hydronephrosis
• Child with hydronephrosis
• Ureteropelvic junction obstruction
• Vesicoureteral reflux
• Posterior urethral valve
• Summary
• References
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3. Objectives
• To discuss approach to antenatal hydronephrosis
• To discuss approach to post natal hydro nephrosis
• To discuss common causes of hydronephrosis in children: PUJ,VUR & PUV
approach and management options
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4. Embryonic and Fetal Development
• kidney-derived from ureteral bud and
metanephric blastema interaction
• 5th wk
ureteral bud arises from
mesonephric (wolffian) duct
penetrates metanephric blastema
• 7th wk- Nephron differentiation begins
• Week 20
Entire collecting system formed
Approximately 30% of nephrons
are present
Nephrogenesis complete by 36th
wk of gestation
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5. INTRODUCTION
• Hydronephrosis
“Hydro” represents “water” and“nephro” represents “kidney”
Not diagnosis in itself
Descriptive term denoting pathological dilatation of renal pelvis and calyces
• Prenatal ultrasounds- ANH currently most common diagnosed prenatal condition
• Goal of management- recognize and treat congenital anomalies that may adversely
affect renal function or cause urinary tract infection (UTI) or sepsis
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6. • Most childhood obstructive GUT lesions- Congenital
Other causes- trauma, neoplasia, calculi, inflammatory processes, surgical
procedures
• Pathophysiologic effects of obstruction depend on:
Level
Extent of involvement
Child's age at onset
Duration (Acute or Chronic)
• Urologic anomalies- in about 0.4% pregnancies
Hydronephrosis- about half cases
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7. Diagnostic pathway
• In summary, clinical investigation of dilated upper tract designed to answer:
1. Is dilatation due to active obstruction?
2. At what anatomical level is obstruction (and most likely pathology)?
3. Is function in obstructed kidney sufficient to justify conservative procedure
or would nephrectomy be more appropriate?
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8. ANTENATAL HYDRONEPHROSIS(ANH)
• Urologic findings- range from mild to significant hydronephrosis
• Prenatal hydronephrosis with AP diameter less than 10 mm
Rarely results clinically significant postnatal outcome
Do not generally need postnatal evaluation
• Likelihood of having significant urinary tract abnormality directly proportional to
severity of hydronephrosis
• Generally, have excellent prognosis
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9. Epidemiology
• Many lesions- identified by antenatal US
GUT abnormality suspected- 1 in 50 fetuses
Significant structural fetal anomaly-1 in 100 fetuses
• Prevalence of ANH ranges from 0.6-5.4%
Approximately 0.5% to 0.6% of all uropathies seen in neonatal period
• 4-15% require intervention
• 1 in 5 neonates will demonstrate spontaneous resolution
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10. Etiologies of ANH
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11. Diagnosis: APD(anteroposterior diameter )
• Renal pelvis APD at renal hilum
Most commonly studied indicator for Assessing ANH
Most valuable measurement
• Factors affecting :
Gestational age
Hydration status and position of mother
Degree of bladder distension
• Limitation :
Operator dependent
Doesn't consider calyceal dilation /parenchymal thinning
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12. Ultrasound...
• Not possible to:
• Distinguish between different causes of dilatation
• Establish diagnosis of obstruction with ultrasound alone
• Sensitivity enhanced by assessing:
• Renal length and cortex thickness
• Degree of calyceal dilatation
• Ureteric dilatation must always be regarded abnormal
• Bladder
Wall thickness
Bladder emptying
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13. Grading
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14. Additional Prenatal Evaluation
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15. Antenatal monitoring
• Depending on:
Severity of hydronephrosis
Bilateral Vs Unilateral
Gestation age
Presence of Oligohydramnios, dilated ureter and bladder
• Unilateral hydronephrosis: one follow up ultrasound in third trimester
• Bilateral hydronephrosis : follow up u/s every 4-6wks
• Findings suggestive of LUTO: even more frequent monitoring
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16. Fetal intervention
• Diagnostic and therapeutic
interventions:
suspected lower urinary tract
obstruction
Oligohydramnios
Should be at specialized centers
• Pregnancy termination- not
recommended
• May involve:
Vesicoamniotic shunting
Amnioinfusion
Percutaneous fetal cystoscopy
Open fetal surgery
Early delivery
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17. Fetal Vesicocentesis
• Allows estimation of urinary electrolytes,β2 microglobulin and osmolality
• Predict renal maturity and function
• Decreasing levels of:
• Na (<100mg/dl),
• Ca (<8 mg/dl),
• Osmolality (<200 mosm/ kg),
• β2 microglobulin (<4 mg/L)
• Protein (<20 mg/dl)
• Identify fetuses likely to benefit from therapeutic interventions
• Parents should be counseled regarding role of vesicoamniotic shunting or in utero
endoscopic ablation of valves
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18. Poor prognostics factors
• Prolonged or early moderate to severe oligohydramnios
• Renal cortical cysts
• Reduced lung area and thoracic or abdominal circumference
• Urinary Na >100 mEq/L, Cl >90 mEq/L, and osmolarity >210 mOsm/L
• β2-microglobulin >6 mg/L
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19. Postnatal Evaluation And Management
• Asymptomatic
• Physical findings in Newborn infants
Palpable abdominal/flank mass
Palpable bladder
Patent draining urachus
Urinary ascites
Infection and sepsis
• Congenital heart disease
• Lung abnormalities
• Anorectal malformations
• Serum creatinine levels
• Initial Radiologic Evaluation:
Serial abdominopelvic sonograms
VCUG
Diuretic renogram
• Antibiotic prophylaxis
• Circumcision considered
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20. Postnatal Sonogram monitoring
• U/S should not be obtained until 72 hours
Exception is severe hydronephrosis
• All GUT should be imaged to detect:
• Dilated posterior urethra (urethral valves),
• Bladder wall thickening
• Ureteral dilation
• Inadequate bladder emptying
• Ureterocele
• Perineal sonography may demonstrate dilated prostatic urethra
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21. Voiding cystourethrogram
• Should be obtained in:
Congenital grade 3 or 4
hydronephrosis
Ureteral dilation
Febrile UTI with hydronephrosis
• May demonstrate VUR, PUVs, or
bladder diverticulum
• Overall VUR detection rate-16.2%
• Mean incidence of VUR into
nondilated kidney was 4.1%
• Prevalence of VUR was significantly
higher in girls than boys
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22. Isotope renography(Diuretic Renogram)
• Principal investigation to diagnose
upper tract obstruction
• Present study of choice for estimation:
Overall and differential renal
function
Efficiency of drainage of kidneys
• Should be obtained in:
Grade 3 and 4, and occasionally
grade 2, hydronephrosis
• Age 4 to 6 weeks- appropriate test
time
• Determinates that affect renal scintigraphy
Poor or immature renal function;Degree
of obstruction; Renal pelvis compliance
Dosage,timing and Renal response to
furosemide
 Region of interest,State of hydration
Time of measurement,Type of protocol
Bladder fullness
Concept of supranormal function
• Phases of dynamic renogram
1. Differential renal function
2. Renogram curves
3. Pressure/flow studies
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23. Diuretic Renogram...
• Technetium-99m (99mTc) MAG3
(mercaptoacetyltriglycine)
Radiopharmaceutical agent of
choice
Superior gamma camera images
Faster clearance rate and lower
background activity
• 99mTc DTPA (diethylenetriamine
pentaacetic acid)
Advantage- diagnostic imaging
can be combined with clearance
study to calculate GFR
• Tc-99m-dimercaptosuccinic
acid(DMSA)
Not useful to determine degree of
obstruction
Gold standard to assess:
Renal parenchyma
Contribution of each kidney to
total renal parenchymal
function(relative renal
function)
Highly sensitive for cortical renal
scars
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24. Magnetic Resonance Urography
• Used primarily when renal US and radionuclide imaging fail to delineate complex
pathology
cross-fused ectopia with hydronephrosis
segmental multicystic kidney
cloacal anomaly
• Advantages:
Superb images of pathology
Differential renal function and drainage
No radiation exposure
• Disadvantages:
Expensive
Need for sedation in infants and young children
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25. Hydronephrosis in children
• Asymptomatic
• Sign and Symptoms depends:
Location of cause
Duration of obstruction
• Ureteral obstruction
Acute- flank or abdominal pain,
nausea and vomiting
Chronic- silent or vague abdominal or
typical flank pain with increased fluid
intake, Flank mass
• Older children, infravesical obstruction
overflow urinary incontinence
poor urine stream
• Complications
Pyelonephritis, lower UTI
Calculi formation
Renal Insufficiency
• Obstructive renal insufficiency
failure to thrive
vomiting, diarrhea
other nonspecific signs and symptoms
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26. Investigation & Diagnosis
• Complete blood count and differential
• Serum electrolytes
• Blood urea and creatinine
• Urine analysis and culture
• Imaging modalities:
Abdominal X-rays
Abdominal and pelvic ultrasound
Intravenous urography
Abdominal CT-scans
Retrograde and Antegrade
pyelography
Retrograde urethrography
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27. Treatment
• Aim of treatment: remove obstruction cause
• Treat aggressively for infections
• Nephrostomy tube- relieve acute hydronephrosis
• Ureteral stents
• Insertion of urinary or suprapubic catheter
• Antibiotics prophylaxis
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28. Specific Causes
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29. UPJ OBSTRUCTION
• Partial or complete blockage of urine
flow from renal pelvis into ureter
• Most common Pathologic cause of
ANH
approximately 50 % of ANH
• Reported incidence- 1 in 500 live
births
1 in 1250 births
• Male-to-female ratio= 2–4:1
• Commonly seen in infants and
children
less commonly in adult
• Left side (66%) more common than
right (33%)- in Children
Reverse is true in adults
• Bilateral- 10-36%
Highest percentage in younger age
group
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30. Embryology and Pathophysiology
• Embryologic base:
Failure of canalization or partial
canalization
Arrest of ureteral wall musculature
development- aperistaltic segment
Improper innervation with diminished
synaptic vesicles at PUJ
Muscular discontinuity
• Types:
Pressure-dependent flow(Intrinsic
obstruction)
Volume-dependent flow(Extrinsic
obstruction)
• Pressure within renal pelvis determined by:
Volume of urine produced
Internal diameter of PUJ and collecting
system
Compliance of renal pelvis
Peristaltic activity of ureter
• Pathophysiologic effect depends on grade of
obstruction
High-grade UPJ obstruction
Low-grade UPJ obstruction
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31. Etiology
Intrinsic(Pressure-dependent)
• Most common
• “Adynamic” segment
• Embryologic disruption of proximal
ureter
Failure to recanalize
Alteration/arrest in circular
musculature development
• Other interluminal causes: Ureteral
valves, polyps, and leiomyomas
Extrinsic(Volume-dependent)
• Create abrupt angulation by kinking or
compressing UPJ
• Causes:
Crossing vessels
Adhesive bands
Arteriovenous malformations
Ureteral(O’stling) folds
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32. Clinical presentation
Antenatal manifestations
• Prenatal maternal-fetal U/S
Suggestive findings for UPJO
Bilateral Hydronephrosis
Other congenital anomalies
• After birth:
vital signs
General health and overall appearance
Respiratory distress or vomiting
palpable abdominal mass
Other congenital anomalies
manifestations
Postnatal manifestations
• Bimodal age distribution
Asymtomatic postnatal Infants
Symptomatic school age children
• Incidental
• Cyclic flank/abdominal pain (Dietl's crisis )
• Renal stone
• Hematuria
• Anorexia and failure to thrive
• Hypertension
• Renal failure
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33. Investigations
• Complete blood count
• Urine analysis and culture
• Serum electrolytes, BUN and
creatinine
• Plain abdominal radiograph
• Abdominal ultrasound
• Abdominal CT-scan
• Abdominal MRI
• Nuclear renal scan
• Intravenous urography
• Voiding cystourethrography
• Percutaneous nephrostography
• Cystoscopy and retrograde
pyelography
• Whitaker antegrade pressure-flow
study
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34. Diagnosis
Ultrasonography
• First maternal-fetal U/S: 16-20 GA
• Suggestive findings:
1. Pelvicalyceal dilation; Parenchymal
atrophy
2. No ipsilateral ureteric dilation
3. Bladder: Normal wall thickness and
cycling
4. Normal amniotic fluid volume
5. Compensatory hypertrophy of
normal kidney
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35. IVU
• Replaced by sonography and
scintigraphy
• For anatomic accuracy and qualitative
information(Renal function and
obstruction)
Features suggestive of obstruction
• Marked dilatation of renal pelvis and
calyces; uniform cortical loss
• Funneling proximal ureter
• Negative nephrogram OR non
visualizated ipsilateral ureter
• Delayed excretion of contrast from
renal pelvis
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36. Diuretic renography
• To diagnose functionally significant
PUJ obstruction
• Contrast washout t 1/2 > 20 minutes
• Differential renal function
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37. CT
• Severity – renal parenchymal thickness
• Establish anatomy of PUJO
• Identification of intrinsic cause or high
insertion PUJ
• Spiral (helical) CT-scan: more useful
provides superior longitudinal
resolution
• Detecting crossing vessels:
Sensitivity of 97 %
Specificity of 92 %
Accuracy of 96 %
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38. MRA/MRU
• Gadolinium-enhanced magnetic
resonance urography (Gd-MRU)
 considered by some investigators
to be more reliable determinant of
renal anatomy and function in UPJ
obstruction
• MRA-provides details of renal
vasculature
 diagnosis of aberrant and
obstructing renal arteries
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39. Voiding cystourethrography (VCUG)
• To rule out VUR
• VUR has been found in as many as 40
% of children with PUJ
• Indicated in children with PUJ:
Dilated ureters on U/S
Febrile UTI with hydronephrosis
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40. Retrograde pyelography
• Commonly performed before open
pyeloplasty
• To precisely identify the location of
UPJ obstruction in relation to other
anatomic structures
• Exclude presence of another distal
obstruction
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41. PREOPERATIVE VASCULAR IMAGING
• “Crossing vessels-Polar vessels
crossing immediately adjacent to UPJ
Exacerbate rather than initiate
obstructive process
• Incidence-11% to 79%
• Primarily important in older children
or adults with UPJ obstruction
• Influence surgical approach
• Imaging modalities:
Digital subtraction intra-arterial
angiography
Helical computed tomography
Contrast-enhanced color Doppler
imaging
Endoluminal sonography
Magnetic resonance angiography
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42. Management
• Remains controversial
• Goal:
Preserve renal function before
contralateral compensatory
hypertrophy occurs
Determine which kidney will truly
benefit from surgery
• Prenatal counseling
Watchful waiting
• 50-80% of all ANH will resolve
spontaneously with postnatal follow-
up
• Postnatal ultrasound:
At least 2 days after birth.
EXCEPTION??
• Ultrasonography and nuclear scans
every 3–4 months
• Only 1-25% require surgery at 4 years
of follow-up
• Antibiotics prophylaxis??
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43. Indications for surgical intervention
• Symptomatic (pain, hypertension, hematuria, secondary renal calculi, and
recurrent UTIs)
• Deterioration of renal function (serial renal function loss >10 %)
• Ongoing parenchymal thinning
• Progressive increase in size of renal pelvis on serial imaging
• Bilateral PUJ obstruction and thinning of renal parenchyma
• Renal pelvic diameter greater than 50 mm?
• Clearance half-time (t 1/2) greater than 20 min
• Differential function less than 40 %
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44. Operative Approaches
• Pyeloplasty Options:
• Open Surgery
Flank approach
Dorsal lumbotomy
 Anterior subcostal extraperitoneal
approach
• Minimally invasive techniques
• Endopyelotomy
• Laparoscopic pyeloplasty
Transperitoneal versus
Retroperitoneal approaches
• Robotic-assisted pyeloplasty
• Other Minimally invasive techniques
 Balloon dilation
 Percutaneous antegrade
endopyelotomy
 Retrograde cutting-wire balloon
endopyelotomy
 Ureteroscopic retrograde
endopyelotomy
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45. • Flap techniques
• Y-V-plasty
• Spiral flap
• Scardino-Prince vertical flaps
• Dismembered pyeloplasty (Anderson-
Hynes pyeloplasty)
• Technique of choice dictated:
Anatomy of renal pelvis
Other intraoperative findings
• Each technique success rate: excess of
90% to 95%
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46. Pyeloplasty options...
Anderson-Hynes pyeloplasty
• Construction of funnel-shaped,
dependent UPJ complex
• Principles:
• Excision of stenotic segment
• Spatulating ureter
• Anastomosing to dependent
portion of renal pelvis
• Gentle tissue handling
Flap techniques
• Preferred in:
Obstructing segment longer than
1.5-2cm
Small extra-renal pelvis not
requiring reduction
High inserting ureter into renal
pelvis
• Foley Y-V plasty
• Spiral or Scardino-prince vertical flap
pyeloureteroplasty
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47. Drainage
• Use of ureteral stents and percutaneous
nephrostomy tubes after open pyeloplasty
remains controversial
• Proponents:
• Ensure urinary diversion
• Maintain ureteral caliber
• Maintain anastomotic alignment
• Decrease risk of urinary leak
• Opponents:
• Nidus for infection
• May erode through anastomotic site
• Need of anesthesia to remove it later
• Renal drainage generally indicated:
• Solitary kidneys
• Simultaneous bilateral pyeloplasties
• Redo pyeloplasty
• Laparoscopic repair
• Very small infants
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48. Outcomes
• Successful- preservation or
improvement of renal function
As high as 98%
• Post pyeloplasty follow up: at least for
2 years
Absence of symptoms
Renal ultrasound
SFU graded hydronephrosis
improvement
Ipsilateral kidney temporal
axial growth
Gradual renal parenchyma
increase
• Diuretic renography
Improved urinary drainage and
differential renal function
• Renal Ultrasound- 4 to 12 weeks
postoperatively
Improvement---> Yearly
Ultrasound
No improvement---> diuretic
renogram
• Renal scars on preoperative DMSA-
add annual BP reading
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49. Complications
• Acute: higher in infants
• Post op pyelonephritis
• Prolonged urinary extravasation
• Delayed drainage through
anastomosis
• Late: manifest as clinical symptoms or
progressive worsening radiographic
studies
• Secondary obstruction: 2.1% of cases
 Causes:
 Scarring or fibrosis
 Non-dependent anastomosis
 Ureteral angulation secondary to renal
malrotation
 Ureteral narrowing distal to
anastomosis
 Treatment: nephrostomy tube or ureteral
stent
 5 basic approaches: Revision
pyeloplasty, ureterocalicostomy,
endopyelotomy, laparoscopy, and
nephrectomy
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50. Vesicoureteral reflux (VUR)
• Retrograde passage of urine from
bladder into ureter
• Most commonly diagnosed during
evaluation following UTI
20% to 50% of children evaluated
for symptomatic UTI
After first UTI:
> 60% of children younger
than 1 year
30% in 2- to 3-year-olds
5% or less in adults
• Asymptomatic patients
ANH
Sibling screening
• Approximately 1% of general
population
• Occur- Isolated or with other
associated anomalies of GUT
• F>M
• Age- inversely related
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51. Pathophysiology
• Oblique entry of ureter into bladder
• Length of submucosal ureter providing
high ratio of tunnel length to ureteral
diameter
• Ureters with marginal tunnels
• Excessively high intravesical pressure
• Propensity for reflux may disappear
with age increment
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52. Classification
• Low vs high pressure
• Primary vs secondary reflux
• Simple vs complex
• International grading system
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53. Diagnosis
Clinical Presentations
• UTI
• Unexplained Febrile Illness
• Associated Genitourinary Anomalies
• Prenatal ANH
Imaging
• Controversial following UTI
1. RBUS
• Children less than 5 years with:
First febrile UTI
Recurrent, nonfebrile UTI
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54. Diagnosis...
2. VCUG
• Contrast VCUG- gold standard
• Allows accurate diagnosis and grading
• Recommended after:
 Abnormality detected by RBUS
 Second febrile UTI
3. Urodynamic Evaluation
• Rule out voiding dysfunction
• History of incontinence, frequency, or urgency
• Managing voiding dysfunction often results in
resolution of reflux
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55. Natural history
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56. Management
• Primary VUR
Non operative management
Operative management
(intravesical or extravesical)
Minimally invasive
Endoscopic procedures
• Secondary VUR
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57. Surgical Correction
• Absolute indications;
Progressive renal injury
Documented failure of renal
growth
Recurrent pyelonephritis on
antibiotic prophylaxis
Breakthrough pyelonephritis by
resistant organisms
Intolerance or noncompliance with
antibiotic suppression
• Relative indications;
High grade (IV–V) reflux in young
children after year of conservative
follow-up
Pubertal age with nephropathy at
diagnosis
Parental preference
Failure to spontaneously resolve
with watchful waiting
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58. Outcomes
• In experts hand- success rate reaches 100%
• USG- required every 6-12 months
• Complications
Early ( persistence, contralateral reflux, obstruction)
Long term (obstruction , recurrent reflux, Hypertension,CKD)
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59. Posterior urethral valves (PUV)
• Obstructive developmental anomaly of
male urethra
• Most common cause of BOO in male
newborns
• Incidence: 1 in 5000–8000 male births
• 2/3rd diagnosed antenatally
• Cause-incomplete dissolution of
urogenital membrane
Types
• Type I (90-95%)
• Type II
• Type III(5%)
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60. Clinical presentation
Perinatal
• Bilateral HUN, distended and thickened
bladder and dilated posterior urethra(key hole
sign)
Neonates
• Delayed voiding or reduced urinary stream
• Respiratory distress
Signs and symptoms
• Abdominal mass/distension (49%)
• Failure to thrive (10%)
• Lethargy
• Poor feeding
• Urosepsis (8%)
• Urinary ascites (7%)
Older boys
• Persistent diurnal urge incontinence
• UTI
• Abdominal distention
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61. Postnatal Radiographic evaluation
U/S
• Unilateral or Bilateral HUN
• Thick walled, distended bladder
• Elongated posterior Urethra
• Favorable prognostic sign: CM
differentiation
• Unfavorable sign :echogenic kidney,
loss of CM differentiation, subcortical
cysts
VCUG
• Dilated,elongated posterior urethra;
abrupt transition to narrower distal
urethra
• Bladder-thickened wall,
trabeculation,diverticulum
• VUR
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62. Management options : Initial management
• Respiratory Support
• Bladder decompression
• Paracentesis : Urinary ascites ; Improves acid balance mismatch & ventilation
• Closely monitor: Electrolytes, blood urea nitrogen (BUN), creatinine, and fluid
status
• Antibiotic prophylaxis
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63. Primary valve ablation
• Once neonate clinically stable
• Well-lubricated infant urethral sounds
can be passed to gently dilate meatus
and glandular urethra
• 7 Fr cystoscope currently available
• 3 Fr Bugbee electrode inserted through
cystoscope
• Valve leaflets incised using low
cutting current at 5 7, and/or 12
o’clock
• Pediatric feeding tube left for 1–2 days
• Success: >90%
• Most common complication: incomplete valve
ablation
• VCUG: 2-4 post op week
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64. TEMPORARY URINARY DIVERSION
Cutaneous vesicostomy
• Blocksom technique
• Indications:
Small or premature neonate
Severe HUN
Urinary ascites
High-grade VUR with poor renal
function
Proximal diversion
• The Sober-en-T ureterostomy
• Indications:
primary surgical intervention,
valve ablation, or vesicostomy
fails to improve
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65. Management of Urinary Extravasation
• Occurs in 5–15% of neonates with PUV
• Dx: U/S, VCUG and renal scintigraphy
• Insert 5/8 grade feeding tube
• Percutaneous drainage
Increase serum cr
respiratory compromise
infection,
hypertension,
significant parenchymal compression
• Percutaneous nephrostomy tube
Persistent extravasation
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66. FOLLOW-UP AFTER INITIAL SURGICAL
INTERVENTION
• Antibiotic prophylaxis; continued until
upper tract dilation improves
• Combined urologic and nephrological
care starting at birth
• Periodic follow-up: US, electrolyte
measurements, BUN and creatinine,
urinalysis, and BP evaluations
• Bladder dysfunction treatment:
anticholinergic(oxybutynin)
• Timed voiding; CIC; Nighttime
drainage
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67. Prognosis
• Overall infant MR: 1% to 3%
• RF: as high as 40% of patients treated for
PUVs
• Long-term prognosis affected mostly by 3
factors:
1. Degree of RD: oligohydramnios; small
subcapsular renal cysts; Increased renal
echogenicity; Loss of CMD
2. Incidence of UTI with or without VUR:
Recurrent febrile UTI; Bilateral VUR
3. Bladder function: severe bladder
dysfunction;Failure to achieve diurnal
continence
Other adverse prognostic factors:
• Persistence of Cr >1.0 mg/dl after initial
therapy
• Renal parenchymal area <12 cm2 on first
postnatal renal US, especially when nadir
Cr=0.8–1.1 mg/dl
• Prenatal diagnosis?
• Younger gestational age
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68. PUV with VUR
• Present in approximately 50%
• Often bilateral
• Vesicoureteral reflux renal dysplasia (VURD) syndrome:
Effect on UTI and renal function?
Advantage?
• After valve fulguration: Resolution in one third to one half of patients
• Another 25% will develop spontaneous VUR
• Overall treatment of PUVs should not change Unless:
Remain high grade after bladder dysfunction treatment
Recurrent UTI despite appropriate chemoprophylaxis
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70. Summary
• Although it is easy to diagnose hydronephrosis, it is, unfortunately, difficult to prove obstruction.
• Most of ANH are transient. Urinary track obstruction or VUR are causes that should soon diagnosed and managed after birth .
• Grading the severity of antenatal hydronephrosis is important as this enables identification of infants that require close follow-up.
• None of the existing imaging modalities can accurately predict which hydronephrotic kidney is at risk for progressive damage and loss of
renal function. With this limitation in mind, sequential radiographic studies can be used to define change that may indicate physiologically
significant obstruction that might require surgical intervention.
• Ultrasound is invariably the first diagnostic work up as well as follow up imaging modality of choice.
• Aim of management in child with hydronephrosis is to relieve obstruction and to treat infection promptly.
• Failure Of recognizing those needing surgical intervention will result in permanent loss of kidney function.
• Most common cause for ANH is PUJ ; Anderson-Hynes pyeloplasty dismembered pyeloplasty is the most commonly done operation for
indicated ptatients.
• VUR is diagnosed usually while working up for UTI; spontaneously resolving is common.
• Once diagnosed and surgically treated, PUV requires lifelong follow-up since it is the most common cause of LUTO leading to end-stage
renal disease (ESRD) in children.
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71. References
• Handbook of pediatric urology 3rd Ed
• Essentials of paediatric urology 2nd Ed
• Nelson Textbook of Pediatrics 21st Ed
• Coran Pediatrics Surgery 7th Ed
• Campbell-Walsh Urology 12th Ed
• The kelalis- king- bellman textbook of pediatrics urology
• Oxford Handbook of Urology 3rd Ed
• Namdev R, Ashraf A, El-Feky M, et al. Hydronephrosis grading (SFU system). Reference
article, Radiopaedia.org (Accessed on 02 Oct 2023) https://doi.org/10.53347/rID-26383
• Journal of pediatrics urology; SFU consensus statement on the evaluation and management of
antenatal hydronephrosis (page 212-231)
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