Antenatal Hydronephrosis(ANH):

Surgical Aspects

Dr Prashant Jain Sr. Consultant

Pediatric Surgery & Pediatric Urology

Dr BLK Superspeciality Hospital, New Delhi

Antenatal Hydronephrosis

Renal anomalies accounts for 17% of all the

congenital anomalies

Hydronephrosis is commonest

(1-5% of all pregnancies)

Management dilemma

ANTENATAL HYDRONEPHROSIS DILATATION OF FETAL RENAL COLLECTING SYSTEM

Transient dilatation

(41 to 88%)

Vesico-ureteric reflux

(10 -20%)

True Obstruction

(20 -50%)

What is True Obstruction???

• Anatomical or Functional impairment in urinary

drainage from kidney which ultimately is going to

affect the renal function

Impairment in Urinary drainage

Dilatation

Impairment of renal functions

True obstruction

Pelvi Ureteric Junction

Uretero-vesical Junction

Bladder outlet Posterior Urethral Valve

Why diagnostic Dilemma?

Transient impairment of urinary flow

Permanent impairment of urinary flow

IMPORTANT TO DIFFERENTIATE

Evaluation Of ANH

- Ultrasound

- Micturiting Cystourethrogram

- Nuclear renal scan

* DRCG

* DMSA

* DTPA

- Magnetic Resonance Urography (MRU)

Antero-Posterior Diameter of

Renal Pelvis (Transverse plane)

Definition of ANH by AP(Antero-Posterior) Diameter

of Renal Pelvis

Mild 4 to <7 mm 7 to <9 mm

Moderate 7 to 10 mm 9 to 15 mm

Severe >10 mm >15 mm

Second trimester Third trimester

Case: Antenatal hydronephrosis

Antenatal scan- 32 wks

Lt hydronephrosis with dilated pelvicalyceal system; No

hydroureter

Antero-posterior(AP) diameter of Lt renal pelvis: 13 mm

AFI: 9

What Next??

13mm

Counseling is Challenge…..

Is it a transient dilatation or pathological

dilatation?

What is accurate diagnostic tool?

How to prognosticate?

How long to follow?

When to operate?

Risk Of Postnatal Pathology

Mild: 11.8%

Moderate:44.1%

Severe: 88.3%

Moderate hydronephrosis (Resolution: 40-

50%)

CAN NOT BE IGNORED

Re-assessment after delivery

Will require regular follow up with USG and

renal scans

Continue pregnancy till term

Post natal

Newborn passing urine

Bladder not palpable

USG KUB after 48-72hrs

AP Diam: 14mm

What Next?

Chemoprophylaxis

USG & DTPA Scan after 1 month of age

What Next?

ANTENATAL HYDRONEPHROSIS

Post Natal USG at 48 -72 hrs

No hydronephrosis

Repeat USG at 3 months

No hydronephrosis No further evaluation

Hydronephrosis present Hydro-ureteronephrosis present

Chemoprophylaxis Early MCU

Mild Moderate/severe

Chemoprophylaxis ??MCU DTPA Scan

USG at 3, 6, 12 mths

B/L HN, BLADDER OUTLET OBSTRUCTION, AND SINGLE KIDNEY NEEDS EARLY EVALUATION

Consider Surgery

Split function is < 40%

Progressive increase in AP diameter

Symptomatic

RK AP DIAMETER LK AP DIAMETER

ANTENATAL - 14 MM

DAY3 - 14 MM

1MTH - 18 MM

3MTH - 18 MM

6MTH 19

12MTH 19

DTPA scan

Advised DTPA scan

At 2 months of age

At 1 year of age

Pyeloplasty

Case: Antenatal Hydronephrosis

20 wks scan

28 wks scan

36 wks scan

Before discharge

Rt AP of Pelvis diameter of 6

mm

Rt AP diameter of pelvis 8 mm

Rt AP of Pelvis diameter of 8 mm

Rt AP diameter of pelvis 7mm

USG at 1mth Rt AP of Pelvis diameter of 8 mm

USG at 3mth & 1 year No dilatation

Antenatal Scan 32 wks

Bilateral hydronephrosis and hydroureter

Bilateral AP diameter 7mm

Bilateral echogenic kidneys

Bladder full; Key hole sign

AFI 8

• POSSIBILITIES????

Antenatal Scan:

Hydrouretronephrosis

Vesico-ureteric reflux

Vesico-ureteric junction obstruction

Posterior Urethral Valve

Counseling

Obstruction at vesico-urethral junction

Need for surgery(Endoscopic

Fulgaration)

Need for long term follow up

Risk of ESRD

Case…

37 wks, LSCS, 1.6 kg

USG: B/L HN & HU

Thinned out renal parenchyma

Thickened and distended bladder

Catheterised

Serum Na: 132

Serum K: 5.3

S. Creatinine:1.6

VBG: Normal

Urine C/S: sterile

MCU

Endoscopic Fulgaration of Valves

Post Operataive

Stable

Polyuria: 5ml/kg/hr(Post operative diuresis)

Catheter removed after 72 hrs

Polyuria Settled in 7 days

Discharged with S.Creatinine of 1meq/l

Chemoprophylaxis

Anticholinergics (Tropan)

Follow up

Intermittent dribbling present

Urinary Stream good

DMSA: left scarred kidney

S.Creatinine : 0.6

Dilatation on USG is less, PVR5 ml

Now 2yrs

No chemoprophylaxis

Needs long term follow up

MCU on follow up

Fulgaration with resectocope

Case

Ante natal USG s/o left moderate hydronephrosis

Repeat USG, dilatation of upper kidney with hydroureter s/o

duplex system and ureterocele

VCUG and MRU

Ureterocoel Incision

Repeat USG after 2 wks

CASE

Antenatal scan 32 wks

Left hydronephrosis AP diam of renal pelvis

11mm

Left ureteric dilatation present

Right Kidney normal

Bladder normal

Post natal

Term male newborn;3kg

Newborn passing urine

Bladder not palpable

Antibiotic prophylaxis

USG KUB after 48-72hrs

AP Diam: 11mm;Ureter dilated

MCU under antibiotic cover

WHAT NEXT

WHAT NEXT

MCU

• Rt Grade III VUR

DMSA Scan

• Scarred left kidney

Follow up Advice

Chemoprophylaxis

Early toilet training

Avoid constipation

Perineal Hygine

Growth/BP monitoring

Regular Urine

examination/ultrasounds/DMSA scan

When to intervene?

Recurrent breakthrough UTI

Progressive scars in DMSA SCAN

Parents choice

Endoscopic injection Vs Ureteric

Reimplantation

STING technique (Subureteric transurethral injection)

43

Follow Up

Chemoprophylaxis stopped

Follow up with nephrologist

CARRY HOME MESSAGE

Do not ignore ANH even if it is transient

Remember AP diameter of pelvis 4/7/10 mm

Most ANH just need surveillance

Hydronephrosis is not synonymous with obstruction

Be positive, supportive, ANH usually have good prognosis.