Download antenatal hydronephrosis

ANTENATAL
HYDRONEPHROSIS
HASAN FARSI
1
What would you do if you
have:
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32-week fetus with normal amniotic fluid and
suspected ureteropelvic junction.
36-week fetus with suspected posterior
urethral valves without oligohydramnios.
23-week fetus with suspected PUV and
oligohydramnios with bladder electrolytes
suggestive of good renal function.
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Amniotic Fluid
 Lungs are correctly formed only in the
presence of sufficient amniotic fluid
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Transudate of maternal plasma
Diffusion across fetal skin
Fetal urine is 1st produced by the end of 9th
week
Concentration ability by 12-14th week
After 18th week all amniotic fluid is fetal urine
UCNA Feb. 1995;21-303
Structural Abnormalities &
Antenatal US
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Detection of renal abnormalities with
antenatal ultrasonography 1st reported in the
70s.
Most renal abnormalities are detected at 18–
20 weeks of gestation
1%
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50% CNS
20% GU
15% GI
8% Cardiopulmonary
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...... Continue Structural Abnormalities & Antenatal US
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2-9/1000 birth
M:F=2:1
50–87% hydronephrosis
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Maximum anteroposterior diameter of renal pelvis
Multicystic dysplastic kidney, autosomal recessive
polycystic kidney disease, renal agenesis and
dysplasia, bladder exstrophy, adrenal hyperplasia,
neuroblastoma, mesoblastic nephroma and genital
abnormalities
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The Society of Fetal Urology
Grading System for ANH
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Grades of Hydronephrosis
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Mild hydronephrosis:
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Moderate hydronephrosis
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Pelvic APD <=1.5 cm and normal calyces
Pelvic APD > 1.5 cm and caliectasis with no
parenchymal atrophy
Severe hydronephrosis:
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Pelvic APD > 1.5 cm, caliectasis and
cortical atrophy
BJU Inter volume 85 Page 987 - May 2000
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Grades of ANH
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grade I: the pelvic APD is 1 cm with normal
calycesgrade
II, APD 1–1.5 cm with normal calycesgrade
III, APD > 1.5 cm with slight caliectasisgrade
IV, APD > 1.5 cm with moderate
caliectasisgrade
V, APD > 1.5 cm with severe caliectasis and
cortical atrophy
Grignon A, Radiology 1986; 160: 645 7
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RPD Measurement &
Incidence of ANH
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18766 Atenatal scans from Bristol UK (RPD=>5mm)
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6292 Antenatal scans from Stoke-on-Trent UK (RPD >10mm)
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ANH 0.59%
ANH 0.65%
6810 Scans from India (RPD >10mm)
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ANH 0.64
Indian Pediatrics 2001; 38: 1401-1404
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The
Final Urological Diagnosis of
426 live-born Infants with Significant
Prenatally Detected Uropathy
British Journal of Urology volume 81 Page 8 - April 1998
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Post Urethral Valves:
Antenatal US
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Prognosis & Severity of ANH
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Prognosis & severity of hydronephrosis: (% needed
surgery or prolonged follow-up):
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RPD > 20 mm, 94%
RPD 10–15 mm 50%
RPD was < 10 mm 3%
Grignon A, Filion R, Filiatrault D, et al: Radiology 1986 Sep; 160(3): 645-7
 Outcome of fetal renal pelvic dilatation (Surgery or
UTI):
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Mild dilation 0%
Moderate dilatation 23%
Severe hydronephrosis 64%
Ultrasound Obstet Gynecol. 2005 May;25(5):483-8.
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Diagnosis & Severity of ANH
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Mild hydronephrosis (RPD 5–9 mm) the
most likely diagnosis is VUR
More marked hydronephrosis
(RPD> 10 mm, and especially if
> 15 mm) PUJ obstruction is the most
common cause
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Prognostic Factors of Fetal
Hydronephrosis
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Severity
Laterality
Ureteric dilatation
Renal parenchymal changes
Abnormalities of bladder size, thickness
and emptying
The presence of concomitant
oligohydramnios
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Unfavorable Prognostic Factors
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Prolonged oligohydramnios
Renal cortical cysts
Urinary contents:
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Na =or>100mEq/L
Cl>90mEq/L
Osmolarity>210mmol
Elevated urinary B2-microglobulin
Reduced lung area & thoracic or abdominal
circumference
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Antenatal Counseling
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Enormous distress to parents
Communication difficulties between the
relevant specialists
Limited understanding of the natural
history
Many anomalies may have no long term
consequence
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Resolution of ANH
18 weeks
32 weeks
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Fetal Intervention
I. No intervention: Regular US
II. Termination of pregnancy (up to 23
weeks)
III. Induction of labor
IV. Prenatal intervention
Only at an experienced institution under
approved protocols
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Intervention
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Male fetus
Second trimester
Severe hydroureteronephrosis
Bilateral
Reasonable fetal urinary indicators
Progressive oligohydramnios.
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Prenatal Intervention for
Urinary Obstruction
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For most fetuses intervention is not
necessary
Decompression will restore amniotic
fluid---> prevent development of fetal
pulmonary hypoplasia
?? Arrest or reverse renal cystic
dysplastic changes
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Vesicoamniotic Shunting:
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Technique
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Complications:
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Vesicostomy or pyelostomy
Pigtail shunt
Shunt blockage or migration,
preterm labor, urinary ascitis,
chorioamnionitis, iatrogenic
gastroschisis, intrauterine death
Outcome:
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Perinatal survival 47%
Post renal insufficiency 87.5%
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Prenatal Evaluation and Treatment for
Fetal Lower Urinary Tract Obstruction"
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The long term outcomes for shunts in fetal
bladder outlet obstruction:
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Etiology:
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Posterior urethral valves 39%
Urethral atresia 22%
Prune Belly Syndrome 39%.
Outcome:
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More than 45% had a GFR of >70ml/min
22% had renal insufficiency
33% were ultimately on dialysis
33% had a transplant
Society for Fetal Urology 35th Biannual Meeting 2005
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Fetal Cystoscopy
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US guided
1.3mm fetoscope
Cannula thru maternal then fetal abdomen then
fetal bladder
Laser ablation of valves
Results
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9 fetuses:4 success
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2 viable at birth
 1 died age 4 months from bronchopneumonia and one
died age 3 m from necrotizing enterocolitis
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A survey instrument was mailed to all
members of the Society for Fetal Urology.
7 case scenarios that addressed critical
decision points in patients with antenatally
detected genitourinary abnormalities.
A total of 112 of 188 Society for Fetal Urology
members (60%) completed the survey.
J UROL Vol. 164, 1052–1056, September 2000
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32-week fetus with normal amniotic fluid and
suspected ureteropelvic junction:
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99% observation & serial US
36-week fetus with suspected posterior
urethral valves without oligohydramnios:
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Most respondents elected no intervention
27% induce early delivery
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…continue
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23-week fetus with suspected PUV and
oligohydramnios with bladder
electrolytes suggestive of good renal
function:
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Intervene antenatally using a
vesicoamniotic shunt (71%)
Serial aspiration (7%)
Amnioinfusion (7%).
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Conclusion
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Situations that warrant antenatal intervention
for a genitourinary abnormality are
exceedingly low and may include:
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Cases of oligohydramnios
Suspected favorable renal function
Absence of life threatening congenital
abnormalities.
In cases with normal amniotic fluid antenatal
intervention is not recommended regardless
of the detected abnormality.
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……..continue Conclusion
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No evidence exists demonstrating the benefit
of antenatal intervention in terms of renal
function and only in a select number of cases
will it benefit pulmonary function.
To our knowledge no scientific data exist that
demonstrate the long-term benefit of early
delivery of cases with antenatally detected,
genitourinary abnormalities.
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Postnatal Investigations
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Abdominal mass
Deficient abdominal wall
Undescended testes
Palpable bladder
Renal profile
US within 1 week (earlier ?? false
because of the physiological oliguria)
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When to perform US post
delivery
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Renal obstruction may be
underestimated or missed on a renal
sonogram obtained 6 days after birth. A
sonogram obtained 6 weeks after birth
is more specific for detecting
obstruction.
AJR Am J Roentgenol. 1995 Apr;164(4):963-7.
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…..continue Postnatal Investigations
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Is it unilateral or bilateral?
Is it solitary kidney?
Are there associated anomalies?
??? Prophylactic antibiotics
Hydronephrosis =obstruction
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Intrauterine Resolution of ANH:Classification of 778 neonatal scans for
evaluation of ANH
Normal renal scans
592 (76%)
Persisting Pyelectasis
120 (15%)
Unilateral renal tract obstruction
(pelviureteric junction 6, vesicoureteric
junction 1)
7 (1%)
Miscellaneous anomalies
59 (8%)
Total
778
Australasian Radiology volume 47 Page 354 - December 2003
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Fate of ANH
18766 pregnancies
ANH=100 (0.59%)
Hydro=64
21(21%) GU Anomaly
Normal=36
43 No anomaly
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Transient Hydronephrosis
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30-50% of ANH
Etiology ??:
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Insufficient maturation of UPJ
Insufficient maturation of VUJ
Increased fetal urinary output (4–6 times
greater before than after delivery)
Partial or transient anatomical or functional
obstructions, e.g. fetal ureteric folds
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New Investigative Modalities for
Post natal Evaluation of ANH
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MR urography:
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MR urography alone was found to be comparable
with conventional combination studies of DRS and
US or urography.
Renal dysplasia
Doppler derived renal resistive index
measures (RI)
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The results of this study do not support the clinical
use of Doppler ultrasound studies in the diagnostic
work-up of congenital hydronephrosis
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Repeat US in 3-6m
Dudley, J A et al. Arch. Dis. Child. Fetal Neonatal Ed. 1997;76:F31-F34
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Persistent Hydronephrosis
without Obstruction
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10-15%
50% resolves by 12 months
Needs long time follow-up
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Take Home Messages
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Antental hydronephrosis is not
uncommon
With the high percentage of history of
consanguinity, the incidence might be
higher in Saudi Arabia
The Obstetrician should be vigilant in
looking for it during the routine
antenatal visits.
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.....continue Take Home Messages
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No evidence exists demonstrating the benefit
of antenatal intervention in terms of renal
function and only in a select number of cases
will it benefit pulmonary function.
To our knowledge no scientific data exist that
demonstrate the long-term benefit of early
delivery of cases with antenatally detected,
genitourinary abnormalities.
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