Fetal hydronephrosis I have to pee: fetal bladder …...11/17/19 1 I have to pee: fetal bladder...
Transcript of Fetal hydronephrosis I have to pee: fetal bladder …...11/17/19 1 I have to pee: fetal bladder...
11/17/19
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I have to pee: fetal bladder outlet obstruction, evaluation
and treatmentJoanne Stone, MD MS
Icahn School of Medicine at Mount Sinai
Fetal hydronephrosis
• Most common birth defect (0.5-5% pregnancies• High sensitivity, low specificity• >50% transient or physiologic
Differential diagnosis
Obstructive
Ureteropelvic junction obstructionUreterovesical junction obstructionMulticystic dysplastic kidneyUreteroceleDuplicated collecting systemPosterior urethral valvesEctopic ureterUrethral atresiaSacrococygeal teratomahydrometrocolpos
Non-Obstructive
Vesicoureteral refluxPhysiologic dilationPrune-belly syndromeRenal cystic diseases
• 1678 infants from 17 centers• Incidence of renal/urinary tract
pathology
• Mild hydronephrosis: 12%
• Moderate hydronephrosis: 45%
• Severe hydronephrosis: 88%
Trimester Mild Moderate Severe
second ≤7 mm 7 to 10 mm >10 mm
third ≤9 mm 9 to 15 mm >15 mm
Classifications
• Renal Pelvic Diameter (RPD)
• Society of Fetal Urology (SFU) criteria
• Urinary Tract dilation (UTD) classification system
Renal Pelvic Diameter• Measures collecting system only
• No consensus on threshold RPD that defines clinically significant fetal hydronephrosis and need for post-natal follow-up
• 4-5mm lowest cut-off
• ≥ 4 – 10mm mild
• > 10mm in 2nd and >15mm in 3rd
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Society of Fetal Urology (SFU)
Dilated renal pelvis only Dilated renal pelvis+ few dilatated calyces
All calcyces dilatedand seen
Grade 3 + parenchymal thinning
Add descriptions: SFU grade 4 UPJ hydronephrosis, SFU grade 4 UVJ hydronephrosis
Urinary tract dilation (UTD) classification system
• Antenatal (A) and Postnatal (P) classification
• Based on US findings, stratified by GA and whether A or P
• Anterior and posterior RPD (APRPD)• Calyceal dilation• Renal parenchymal thickness• Renal parenchymal appearance• Bladder abnormalities
• Normal: APRPD• < 4mm 16 – 27 w• < 7mm at ≥ 28 w
• A1: • normal urinary tract with 4 - < 7mm APRPD
at 16-27 w• or 7 to <10 mm at ≥ 28 w with or w/o
central calyceal dilation
• A2-3: • APRPD ≥ 7mm at 16-27 w
• or ≥10mm at ≥28 weeks, peripheral calyceal dilation, ureteral dilation, renal parenchymal or bladder abnormalities
What class?
16-27 weeksAPRPD 4-7mmCentral calyceal dilation
≥ 28 weeksAPRPD 7-<10 mmCentral calyceal dilation
A1
A2-3
UTD system:Requires more descriptive
terms to communicate
Natural history
• Mild – 88% resolve in fetal/neonatal period• Moderate- severe: 30% persisting in 3rd trimester require postnatal
surgery
Evaluation of fetal hydronephrosis
• Severity and bilaterality increase risk of congenital anomalies of kidney and urinary tract• Repeat US in 3rd trimester – prognosis for intervention postnatally
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Hydroureter
• Vesicoureteral reflux (VUR)• Obstruction distal to
uretopelvic junction (uretocele, megaureter, posterior urethral valves)
Ureterocele
• Cystic dilation of distal intravesical portion of the ureter• Often at orifice draining upper pole of duplicated kidney
Renal parenchyma
• Thinning• < 3mm• Does not
necessarily correlate with poor renal function
• Cortical cysts• Echogenic kidneys
Bladder
• Bladder thickness –obstruction distal to bladder• Keyhole sign• Bladder enlargement:
sagital diameter of GA weeks (mm) + 2 mm• Often PUV• Urethral atresia• Look for ureteroceles
Diagnosis of LUTO
• 1/5,000 – 1/25,000 pregnancies• Markedly distended bladder often with thickened wall• Dilated ureter and calyces – 40-50% LUTO• Cortical cysts, hyperechoic kidneys – end stage• Differential diagnosis• PUV – males• Urethral atresia –females
• r/o persistent cloaca• Caudal regression• Mega-cystis--microcolon-intestinal hyperperistalsis syndrome
• ureterocele
Evaluation of LUTO
• Anatomic survey• Fetal echocardiogram• AF volume assessment• Genetic testing (10% associated with Trisomies 13, 18, 21)• f/u assessments• With oligohydramnios and desire for possible intervention, assess
renal function
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Treatment
• Indications• Male fetus• Second trimester• Bilateral disease• Reasonable fetal urinary studies• Progressive oligohydramnios
• Options• Vesico-amniotic shunting• Valve ablation via cystoscopy• Vesicostomy• Serial amnioinfusion
Evaluation of fetal urine
• 2 consecutive vesicocenteses• 22g spinal needle• Color flow to avoid umbilical
arteries• 1st bladder tap
• Can send for genetic evaluation (CMA)
• +/- electrolyte analysis• 2nd bladder tap
• 24-48 hours later• Na, Chl, Osm, Ca, beta-2
microglobulin
Urinary component Favorable prognosis
Sodium (Na) < 100 mEq/l
Chloride (Cl) < 90 mEq/l
Osmolarity (Osm) < 210 mEq/l
Calcium (Ca) <2 mmol/l
Beta-2 macroglobulin < 2 mg/l
Fetal urine hypotonic until 22 weeks and not necessarily reflective of renal function at birth despite intervention
• Calcium and sodium > 95%ile for GA – best predictors for abnormal post-natal renal function• Due to small study samples and varying thresholds of urinary
markers, fetal urine analysis is still not helpful in predicting postnatal renal outcome.
Proteomic approach: 12 peptides in fetal urine were predictive of developing end-stage renal disease
Fetal serum beta-2 macroglobulin better correlated with postnatal serum creatinine
Klein J, Let al Sci Transl Med.2013;5:198 Luton D, Deet al. Clin Biochem.2013;46(15):1607–10
Vesico-amniotic shunting
• Technique• Seldinger technique• Pigtail shunt ( Rodeck, Rocket, Harrison)
• Complications• Shunt blockage, migration• Preterm labor, urinary ascites, infection, IUD
Trial stopped early due to poor recruitment
Of 12 neonates surviving to 28 days:2/12 showed no renal impairment (shunt)
Analysis based on RX: benefit of shunt on survival at 28 days (RR 3.2, 95% CI 1.06-9.62), 1 year (RR 4.27, 95% CI 1.07-16.96), and 2 years of age (RR 4.27, 95% CI 1.07-16.962/10 who survived to age 2 had no renal impairment
May improve survivalLong term outlook is poor
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2016 retrospective study on 30 male fetuses – survival at 1 and 2 years 57 and 54% and normal renal function in 76 and73% survivors at 1 and 2 years
Fetal cystoscopy for PUVLimited data including systematic review of 4 papers on cystoscopy vs VAS – no improvement in survival in one particular approach
2015 case control of 34 fetuses – cystoscopy improved diagnosis and allowed better selection of fetuses with true PUV for VAS placement
Study of 20 fetuses undergoing cystoscopy and laser ablation: 9 terminated, 11 delivered at mean 37 weeks
8/11 survivors had normal renal function3/11 awaiting transplant
Sananes Net al. PrenatDiagn. 2016;36(4):297–303, Ruano R et alUltrasound ObstetGynecol. 2015;45(4):452–8, Morris RK et al Ultrasound Obstet Gynecol.2011;37(6):629–37Martínez JM et al Fetal Diagn Ther. 2015;37(4):267–7,
• 30% technical failure with fetal cystoscopy• No valid proof of superiority of FC vs VAS• VAS may not improve kidney function and may worsen urologic
function• FC limited by technical factors and lack of reproducibility
Take aways
• Renal pelviceal dilation/hydronephrosis
• Mild – 88% resolve in fetal/neonatal period
• Moderate- severe: 30% persisting in 3rd trimester require postnatal surgery
• UTD classification helpful in communication between subspecialties
• LUTO
• Treatment depends on fetal sex, renal function, oligohydramnios
• Urine studies not that helpful especially < 22 weeks
• Shunts may improve survival but outcome is still poor
• Currently no evidence of superiority of cystoscopy over VAS