Lower Urinary Tract Obstruction LUTO or Bladder Outlet Obstruction BOO. Miss Harriet Corbett Consultant Paediatric Urologist

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1 Lower Urinary Tract Obstruction LUTO or Bladder Outlet Obstruction BOO Miss Harriet Corbett Consultant Paediatric Urologist

2 Aims To give an overview of the anomalies we encounter presentation of LUTO how to investigate suspected LUTO how to manage them long term outcomes

3 Causes of LUTO Partial obstruction Posterior Urethral Valves Obstructing ureteroceles Neuropathic bladder (functional) other, rare In association with a patent cloaca Anterior urethral valves, Cobbs collar, Congenital urethral stricture, Polyps Complete obstruction Urethral atresia

4 Posterior Urethral Valves Commonest cause of LUTO in children Males only 1:5,000 Sporadic Only v. rare familial cases Associations Trisomy 21 (not in all series) Kupferman 1996 Paediatr nephrol (find association), Qureshi 2000 Fetal Diagn (do not) UDT in up to 12-17%

5 Posterior Urethral Valves Obliquely orientated membrane (not actually valves) From region of veru through external sphincter to anterior urethral wall a very wide spectrum (veru)

6 Posterior Urethral Valves Young s classification - no longer considered valid: Type I pair of oblique postero-anterior folds directed distally from veru (95%) veru enlarged?in fact a single membrane, bicuspid due to catheters Type II folds between veru and bladder neck *?if these exist - considered to be non-obstructing Type III membrane/diaphragm distal to veru (5%) Dewan et al. 1990s If perform cystoscopy before catheter, find Type III Catheter converts it to Type I Proposed new terminology: COPUM Congenital Obstructing Posterior Urethral Membrane A membrane rather than valve leaflets

7 Posterior Urethral Valves Embryology - theories e.g. abnormal integration of Wolffian ducts into the urethral wall, abnormal cloacal membrane Krishnan et al. J Urol 2006: persistent urogenital membrane

8 Pathophysiology Urinary tract obstruction May be evident as early as 14 weeks reduced liquor volume reduced volume of urine passed consequences on fatal lung and posture abnormal bladder wall chronic raised intravesical pressure abnormal proximal urinary tract dilated ureters, abnormal kidneys

9 Uterus Small lungs Oligohydramnios Hydronephroureter Damaged kidneys Damaged bladder Club feet

10 Why do they matter so much? Respiratory insufficiency in severe cases May be fatal Commonest cause of BOO/LUTO in childhood Commonest cause of childhood renal failure Approx 25% ESRF Bladder dysfunction In 25-30%

11 Presentation of PUV 1. Antenatal must be considered in any baby (boy) with bilateral AN hydro or abnormal bladder 2. Early postnatal 3. Infants 4. Childhood 5. Later

12 Antenatal USS Urinary tract = commonest system to find anomalies Mild dilatation of renal pelvis in 1:100 pregnancies Significant problems 1:500 70% of anomalies are detected at 20 weeks BUT: 80% of antenatal findings are non specific

13 Aetiology & incidence of antenatal hydronephrosis Transient hydronephrosis 41 88% Pelviureteric Junction obstruction (PUJ) 10 30% Vesicoureteric reflux 10 20% Vesicoureteric junction obstruction (VUJ) or megaureters 5 10% Ureterocele/ectopic ureter/duplex system 5 7% Multicystic dysplastic kidney 4 6% Posterior Urethral Valves/urethral atresia 1 2% Nguyen HT et al. The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis. J Pediatr Urol 2010:6:212-31

14 Which ones to worry about OLIGOHYDRAMNIOS risk of pulmonary hypoplasia Anything BILATERAL Ureters or kidneys Anything that includes bladder abnormality Especially the Keyhole sign Abnormal solitary kidneys

15 Antenatal diagnosis 55% suspected at 20wks Further 20-30% detected later Bad signs Detect <24wks (later = better) Oligohydramnios Bright kidneys...consider TOP if v.early/severe oligo... Refs: Sarhan, 2008 & BAPS CASS survey 2018

16 PLUTO Percutaneous shunting for Lower Urinary Tract Obstruction LUTO : 60% PUV, 21% other, 5% c some etc Metanalysis of literature to date suggests a benefit from shunting in utero ANY fetus with LUTO where it is uncertain if shunting will help to be randomised to shunt/no shunt Needed 200 patients to show 20% difference in mortality Didn t recruit enough

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18 What to do with a baby with antenatal urological abnormality Ultrasound Scan Timing depends upon antenatal scan so it does matter what the antenatal scan showed afterall! Urgent postnatal ultrasound at hour old, if: oligohydramnios / lung abnormality bilateral dilation OR unilateral with bladder abnormality solitary abnormal kidney if normal :repeat 3 to 7 days later if still normal repeat at 6 weeks if still normal, no follow up required

19 Protocol 1 1. Renal dilation with oligohydramnios or lung abnormality 2. Bilateral renal dilation 3. Unilateral renal dilation with ureteric dilation or bladder abnormality or contralateral kidney abnormal Urgent postnatal ultrasound Discuss with Paediatric urologist MCU* Urgent to exclude valves Posterior urethral valves Vesicoureteric reflux No PUV, No VUR URGENT REFERAL Antibiotics Referral Paeds/nephrology/urology MAG3 3months Referral Urology

20 False Alarm - bilat hydro due to VUR

21 PUV case 1: baby AT Bilateral hydronephrosis & oligohydramnios on 34 week scan Elective CS delivery at 36 weeks Ventilated for respiratory distress Pneumothorax O 2 requirement Creatinine 147 on D3

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23 Beware the early USS This baby had normal kidneys on a Day 1 USS But they looked like this on day 13

24 PUV case 2: Stoke baby Antenatal diagnosis of bilateral hydronephrosis and dilated bladder Catheterised after birth, transferred to AH USS = gross bladder wall thickening & significant bilateral hydro MCUG = poor bladder with PUV

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26 18 months post treatment

27 Management 1 Drain bladder Ideally URETHRAL catheter Beware v. thick bladder wall obstructing VUJ SPC difficult due to thick wall Alternatives: vesicostomy, ureterostomy(ies), nephrostomy(ies) Monitor U&E Nephrology input Allow stabilisation before anything else

28 Micturating CystoUrethroGram

29 B PU B Bladder Posterior urethra B PU PU B B PU PU

30 Endoscopic ablation Resectoscope Cold knife Whittaker hook etc. +/- circumcision Management 2 Rpt cystoscopy at 3/12 Monitor. Long term Through puberty

31 Presentation of PUV 1. Antenatal 2. Early postnatal respiratory distress and abnormal U&E urosepsis clinical LUTO = big bladder, big kidneys, big abdomen (urinary ascites) 3. Infants 4. Childhood 5. Later

32 PUV case 2: TH Antenatal dx of club feet - nil else Presented at 6 weeks of age with frank haematuria likely UTI (>1000 WCC, but mixed growth) terrible USS

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36 Presentation of PUV 1. Antenatal 2. Early postnatal 3. Infants soft signs - FTT, vomiting, poor feeding urosepsis - often very unwell clinical LUTO = big bladder, big kidneys, big abdomen (urinary ascites) 4. Childhood 5. Later

37 Presentation of PUV 1. Antenatal 2. Early postnatal 3. Infants 4. Childhood 5. or Later FTT, UTIs, wetting, abnormal voiding Renal failure

38 DC presented at 16 years of age with frank haematuria First ever urinary tract symptom Though imperfect bladder function likely overlooked in view of T21 Trisomy 21 UTI

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42 Long term: rule of thirds BLADDER: ⅓ normal ⅓ poor... Late potty training, wetting ⅓ bad... Overactive/poor compliance/myogenic failure with time - may need ISC/surgery etc KIDNEYS ⅓ normal ⅓ marginal ⅓ poor progressing to CRF / transplant *** nadir creatinine and bladder dysfunction are risk factors for ESRF (DeFoor 2008 J Urol)

43 Bladder Crucial to protect upper tracts Long term... Kidneys Protect by minimising infection, VUR etc Infection Minimise to protect kidneys Blood pressure Fertility Poor semen, poor ejaculation & UDT

44 Non - PUV Causes of LUTO Obstructing ureteroceles Neuropathic bladder (functional) other, rare Urethral atresia In association with a patent cloaca Anterior urethral valves, Cobbs collar, Congenital urethral stricture, Polyps

45 Obstructing Ureteroceles The minority of ureteroceles Most detected antenatally associated with duplex systems (single system ureteroceles often innocent)

46 Duplex systems: plenty of scope for abnormality but both moieties may be normal

47 Duplex systems: if abnormal: lower moiety - ureter inserts lateral and above medial ureter, may be too lateral - likely to have VUR

48 Duplex systems: if abnormal: upper moiety - ureter inserts medially and below, often ectopic, may have ureterocele The Weigert-Meyer rule states that the upper pole ureter is the ectopic ureter and its orifice inserts inferomedially in the bladder in relationship to the lower pole normal ureter.

49 » Ureteroceles» obstruct their own moiety» often No / poor function (dysplastic)» if not causing other problem then nil to do» BUT» if obstructing lower pole ureter / other side / bladder neck» OR get infected above» need puncture» or other op» may prolapse / be very ectopic» vagina» urethra

50 Obstructing ureterocele: TH Term boy with bilateral antenatal hydronephrosis Well at birth Initial early scan not bad but repeated according to protocol Repeat scan ~1 week later quite abnormal

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54 Urethral Atresia Technically non survivable No urine = no amniotic fluid Potters syndrome equivalent

55 Urethral Atresia Survivable if urine can pass e.g. Patent Urachus, Vesicoamniotic shunt

56 Summary PUV is the commonest cause of LUTO Be suspicious any boy may have PUV! Urologists happy to advise

57 Any Questions?