Extrophy and Epispadias
Key points
Incidence/Prevalence
Bladder extrophy 1:50000
Primary epispadias 1:120000
Cloacal extrophy 1:300000
Live births
Pathophysiology
Early defects in cloacal membrane - ‘rupture hypothesis’
Overgrowth of cloacal membrane separates mesodermal components of abdominal wall - ‘wedge-effect hypothesis’
Possible embryology of cloacal extrophy: Cloacal membrane apoptosis before descent of urorectal septum
Exposed bladder plate in continuity with exposed urethral plate
In severe epispadias - posterior urethra merges with bladder neck, verumontanum can be in
bladder
In females with primary epispadias - sphincter weakness is always present
The vascular structure of an epispadias penis is unique - blood supply to the corpora, hemiglans, and urethral plate differs
Surgical correction therefore requires a complete disassembly of the penis
Bladder extrophy
Antenatal features
Unable to visualise bladder
Low set umbilical cord
Bulging bladder plate
Maternal AFP elevated
Aims of bladder extrophy surgery
Competent receptacle (bladder) for storage
Prevent upper tract damage
Cosmetically acceptable genitalia providing good functional outcomes in terms of continence an
sexual function.
Cloacal extrophy
Aetiology unknown
Proposed risk factors:
Multiple births
Young maternal age
Poor socioeconomic status
Use of clomiphene
Antenatal features:
Classical elephant trunk in 33% - can be seen after 12 weeks
Major criteria:
Non-visualisation of bladder
Infraumbilical abdominal wall defect
Exomphalos
Myelomeningocoele (MM)
Associations
Spinal dysraphism - MM/tethered cord in >50%
Omphalocoele extrophy imperforate anus spinal defects (OEIS) complex
Undescended testes
Unilateral renal agenesis
Pelvic kidney
Ureteric duplications
Malrotation
SB atresia
Inguinal hernia
Club foot
Limb shortening
Examination
2 bladder halves separated by caecum and ileal segment
ARM
Bifid phallus or vagina and uterus
Patulous bladder neck
Pubic and recti diastasis
Short colon
May be covered
May be duplicated
Needs system by system examination
Investigations
Karyotype
Same as VACTERL screen
Outcome
10% mortality
50% have permanent colostomy
Approx 80% achieve dryness and faecal continence
Poor quality of life related to genitalia and sexual function
Unlikely to sustain viable pregnancy
Special scenario - Bladder extrophy
Ensure clinically stable/resuscitated
Confirm diagnosis with Antenatal history - check if/where counselling was done
Antenatal USS -
Unable to visualise bladder/Bulging bladder plate
Low set umbilical cord
Examination
Classify epispadias like Hypospadias - penopubic for base
Examine for intact pubic symphysis
Testes usually descended - upwards rugae on scrotum
Cover with film
Feed, give Vit K
No need for antibiotics at birth
XR pelvis - document the degree of pubic diastasis
USS KUB for renal tract abnormalities
Transfer to specialist centre - GOSH/Manchester
GOSH - neonatal bladder closure, EUA at 3 months, reopen bladder, Cohen reimplant, repair epispadias by mobilising and closing corpora at 6 months
Steps of bladder closure
Catheterise UOs
Mobilise bladder plate
Excise polyps, close hernia sacs
Dissect inferiorly, close bladder in midline bringing stents out anteriorly
Place urethral stent
Push bladder posteriorly
Close pubic rami with sutures - sometimes osteotomy needed
Other options:
Complete primary repair of exstrophy (CPRE) - all repairs at once as neonate - technically challenging
Modern staged repair of exstrophy (MSRE) - bladder closure at birth, epispadias closure at age 2, bladder neck reconstruction at age 5 when bladder has enough capacity
Follow up:
Immediate post op - Monitor for wound and bladder dehiscence
Treat as neuropathic bladder - upper tracts must be protected
Start CIC
Surveillance USS KUB as per neuropathic bladder - Baseline DMSA + Urodynamics 3 months after repair
Repeat Urodynamics if clinical change
Outcomes:
If managed with CIC etc - at 10 years:
70- 80% dry by day
30-40% dry by night
Males
13% need bladder augment
90% males can achieve erections, but have retrograde ejaculation - fertility rate 20%
Females
33% need augment
Females have normal fertility - may need c-section
Special scenario - Cloacal extrophy
Ensure clinically stable/resuscitated
Antenatal history - check if/where counselling was done
Classical elephant trunk in 33% - can be seen after 12 weeks
Major criteria:
Non-visualisation of bladder
Infraumbilical abdominal wall defect
Exomphalos
MM
Examination:
Defect
Pubic diastasis
Size of exomphalos
System by system examination
Spine + Anus (OEIS)
Limb abnormalities
Investigation:
XR pelvis - document the degree of pubic diastasis
USS KUB for renal tract abnormalities
Karyotype
Echo
Management:
Suture umbilical cord at birth - do not clamp as may injure bladder
Cover organs
Prophylactic antibiotics
Neonatal single stage (for stable patients only):
Complete closure of abdominal wall, bladder, phallus, +/-osteotomies
Try to avoid ileostomy
Colostomy: Dissect caecal plate off hemibladders, tubularise. Then either turn into proximal colostomy or bring out distal end
Staged:
Colostomy
Cover exomphalos and hemibladders (converts to bladder extrophy)
Bladder closure usually at 6-12 month when enough bone for osteotomies and tension free repair and adequate reservoir
Place ureteric stents, urethral and suprapubic catheters
May need later bladder augment and mitrofanoff
Pullthrough at 3-4 years if good potential for continence (<50% of patients) (e.g spinal abnormalities, sphincter, walking, gluteal cleft)
References
Essentials of Pediatric Urology, 3rd edition, 2022, Chapter 15 Bladder Extrophy and Epispadias
Koehler, Shannon, et al. "Cloacal Exstrophy." Pediatric Surgery NaT, American Pediatric Surgical Association, 2020. Pediatric Surgery Library, www.pedsurglibrary.com/apsa/view/Pediatric-Surgery-NaT/829526/all/Cloacal_Exstrophy.