Basics
Description
The exstrophy-epispadias complex is a rare spectrum of multisystem birth defects involving the genitourinary and gastrointestinal tracts, musculoskeletal system, pelvic floor, and bony pelvis. It is composed of epispadias, bladder exstrophy, and cloacal exstrophy. The latter two conditions present with an open bladder through the anterior abdominal wall. �
- The least common variant of the complex, complete epispadias presents with a closed bladder and dorsally open urethral meatus.
- Cloacal exstrophy is the most severe variant, presenting with a large omphalocele, imperforate anus, shortened colon, bladder halves with cecum interposed between, associated cord defects, and multiple upper urinary tract and limb anomalies. All three forms are associated with a pubic diastasis.
Epidemiology
Incidence
- Bladder exstrophy
- Male-to-female ratio is between 2:1 and 4:1.
- Between 1:10,000 and 1:50,000 live births
- Risk in offspring of individuals with bladder exstrophy and epispadias is 1:70 (500-fold greater than general population).
- Risk of recurrence in family is approximately 1:100.
- Epispadias
- Risk of male epispadias: 1:117,000 live births
- Risk of female epispadias: 1:484,000 live births
- Cloacal exstrophy
- Male-to-female ratio is between 1:1 and 2:1.
- Cloacal exstrophy is exceedingly rare, with an incidence between 1:200,000 and 1:400,000 births (decreasing incidence with prenatal diagnosis and termination).
Risk Factors
Bladder exstrophy: only known association is related to offspring of in vitro fertilization pregnancies �
Pathophysiology
Embryology �
- Normal development
- By week 2 of gestation, the cloacal membrane is located at the caudal end of the infraumbilical abdominal wall.
- At week 4 of gestation, mesenchyme from the primitive streak migrates between the layers of the cloacal membrane to reinforce the abdominal wall while the cloacal membrane regresses.
- Bladder exstrophy
- Unclear pathogenesis, but there is an error in embryogenesis
- The cloacal membrane may overdevelop and prevent mesenchymal migration, which inhibits formation of normal lower abdominal wall.
- Without reinforcement, the cloacal membrane ruptures. The timing of this rupture determines the variant of the exstrophy-epispadias complex. In bladder exstrophy, rupture of the membrane occurs after the urorectal septum has descended, dividing the genitourinary and gastrointestinal tracts.
- Cloacal exstrophy
- Abnormally large cloacal membrane ruptures prior to division of the cloaca by the urorectal septum.
Diagnosis
Physical Exam
- Bladder exstrophy
- All cases have pubic diastasis (mean of 4.8 cm) caused by outward rotation of the innominate bones and iliac wings.
- The exstrophied bladder and posterior urethra are exposed through a triangular defect in the anterior abdominal wall and are bound by the umbilicus superiorly, the two separated pubic bones laterally, and the anus inferiorly.
- The anus is anteriorly displaced, shortening the distance between it and the umbilicus.
- Boys commonly have indirect inguinal hernias that are prone to incarceration because the perineum is short and broad due to the compromised pelvic floor. Less common when osteotomy is used.
- Male genital anomalies
- Penis is 50% shorter and 30% wider than non-exstrophy boys.
- Corpora cavernosa are short and widely separated secondary to the pubic diastasis.
- There is a short urethral plate and a marked dorsal chordee causing the penis to curve upward.
- Epispadias always presents with the lower tract open from the tip of the penis to the dome of the bladder.
- Female genital anomalies
- Mons pubis is laterally displaced, with a bifid clitoris secondary to the diastasis.
- Vagina is short and wide.
- Vagina and introitus are displaced anteriorly, with the cervix in the anterior vaginal wall.
- All female patients are at an increased risk for uterine prolapse in adolescent and adult life.
- Urinary defects
- Bladder mucosa at birth usually appears normal but may be ectopic or contain polyps.
- Exstrophic bladder may develop slowly prior to closure.
- Upper urinary tract usually normal but may observe horseshoe, pelvic, hypoplastic, solitary, or dysplastic kidney.
- Most children have vesicoureteral reflux requiring correction at the time of their continence procedure.
- Cloacal exstrophy
- Two halves of the exstrophied bladder are separated by an exstrophied ileocecal bowel segment with various amount of hindgut present.
- Omphalocele usually present; varies in size.
- Imperforate anus is usually present.
- Vertebral and neurologic abnormalities (lumbar myelodysplasia, hemivertebrae) are present in >50% of children.
- Upper urinary tract anomalies (duplicated systems, horseshoe kidney, pelvic kidney) are seen in up to 70% of children.
- Penis may be duplicate or diminutive.
- Bifid vagina and uterine abnormalities
Diagnostic Tests & Interpretation
Imaging
- Prenatal sonographic findings between 15th and 32nd weeks of pregnancy demonstrating absence of normal fluid-filled bladder, an anterior abdominal mass increasing in size, low-set umbilicus, and wide pubic ramus are suggestive of bladder exstrophy.
- A baseline renal ultrasound and KUB after birth will demonstrate renal abnormalities and the pubic diastasis, respectively.
Treatment
Surgery/Other Procedures
Goals: Provide urinary continence with a compliant bladder, preserve renal function, and surgically reconstruct the phallus for cosmesis. �
- Modern staged repair of bladder exstrophy (MSRE)
- In the early neonatal period, bladder, posterior urethra, and abdominal wall closure is performed with or without osteotomy.
- Closure of the urethra occurs at 6-12 months of age.
- Bladder capacity is annually measured with gravity cystogram.
- If bladder has adequate capacity and patient desires continence (between 5 and 9 years), a continence procedure is performed with ureteral reimplantation.
- Noncandidates or those who fail continence may require bladder neck transection, augmentation cystoplasty, and continent urinary diversion.
- Results and complications: Daytime continence in 60-80% following bladder neck surgery may require clean intermittent catheterization (long-term follow-up). Minimal risk for upper urinary tract changes or hydronephrosis.
- Small bladder capacity and failed primary closure are predictors of postsurgical incontinence.
- Complete primary repair of exstrophy (CPRE)
- Bladder and abdominal wall closure, bladder neck reconstruction, and epispadias repair completed in single procedure. May be performed with or without osteotomy.
- Total penile disassembly dissects the urethral plate from corporal bodies to posteriorly position the bladder neck into the pelvis.
- Results and complications: Daytime continence and volitional voiding in selected patients in up to 20% over 5 years of age; additional bladder neck surgery to gain continence is usually required; >50% require subsequent hypospadias repair and bladder neck fistula rate is up to 40%. Penile disassembly may cause penile soft tissue loss.
- Role of osteotomy and immobilization in all closures
- Recommended in patients with a diastasis >4 cm who no longer have a malleable pelvis, which usually occurs after 72 hours of age
- Bilateral transverse anterior innominate and vertical posterior iliac osteotomies performed by pediatric orthopedic surgeon.
- Fixator pins and external fixation devices can be placed and left postoperatively for 4-6 weeks.
- Pelvis immobilized and patient is placed in modified Buck or Bryant traction to increase chance of success.
- Complications: increased risk of transient nerve and muscle palsies (which typically resolve), delayed ileal union, and superficial infection at pin sites
- Complications for both types of closure:
- Dehiscence, bladder prolapse, bladder outlet obstruction, stone formation, hydronephrosis, and vesicocutaneous fistula formation may occur. Patients must be followed carefully.
- Chance of long-term continence decreases with each additional closure attempt.
- Failed bladder neck repair in 20-50% may require further reconstruction.
- 60-95% cosmetic and functional success of epispadias repair with a straight penis with erections
- Urethral strictures and urethrocutaneous fistula are the most common complications of epispadias repair seen in ≤25% of patients.
- Adenocarcinoma of the bladder is 400 times more likely than in the normal population. This disease is not reported in adults who have had bladder closure after infancy.
- Fertility and pregnancy
- Following successful repair, sexual function and libido are normal.
- Following epispadias repair, up to 87% of boys have erections.
- Expect retrograde and small-volume ejaculation.
- Males can have successful impregnation with assisted reproductive techniques.
- Females can achieve pregnancy, but uterine and cervical prolapse are common following pregnancy. Cesarean section is recommended.
Inpatient Considerations
Initial Stabilization
Postnatal and nursery care: �
- Instead of umbilical clamp, tie umbilical cord with 2-0 silk to avoid trauma
- Cover bladder and other exstrophied bowel/omphalocele with a hydrated gel dressing or plastic wrap to prevent mucosa from sticking to clothing or diapers.
- Transfer immediately to an appropriate center for evaluation and management by a pediatric urologist and an experienced team.
Discharge Criteria
- Prophylactic antibiotics should be continued in all children until antireflux procedure or resolution of vesicoureteral reflux.
- Maintain close follow-up with surgeon.
Ongoing Care
Prognosis
Current treatments preserve the bladder in nearly every patient and allow for continence through the urethra, providing an excellent overall prognosis. There can be favorable long-term outcome with early intervention by a pediatric urologist. �
Additional Reading
- Baird �AD, Nelson �CP, Gearhart �JP. Modern staged repair of bladder exstrophy: a contemporary series. J Pediatr Urol. 2007;3(4):311-315. �[View Abstract]
- Ebert �AK, Reutter �H, Ludwig �M, et al. The exstrophy-epispadias complex. Orphanet J Rare Dis. 2009;4:23. �[View Abstract]
- Gargollo �PC, Borer �JG, Diamond �DA, et al. Prospective followup in patients after complete primary repair of bladder exstrophy. J Urol. 2008;180 (Suppl 4):1665-1670. �[View Abstract]
- Gearhart �JP, Baird �AD. The failed complete repair of bladder exstrophy: Insights and outcomes. J Urol. 2005;174(4):1669-1672. �[View Abstract]
- Grady �RW, Mitchell �ME. Complete primary repair of exstrophy. J Urol. 1999;162(4):1415-1420. �[View Abstract]
- Inouye �BM, Massanyi �EZ, Di Carlo �H, et al. Modern management of bladder exstrophy repair. Curr Urol Rep. 2013;14(4):359-365. �[View Abstract]
- Schaeffer �AJ, Stec �AA, Purves �JT, et al. Complete primary repair of bladder exstrophy: a single institution referral experience. J Urol. 2011;186(3):1041-1046. �[View Abstract]
- Stec �AA, Tekes �A, Ertan �G, et al. Evaluation of the pelvic floor muscular redistribution after primary closure of classic bladder exstrophy by 3-dimensional magnetic resonance imaging. J Urol. 2012;188(4)(Suppl):1535-1542. �[View Abstract]
Codes
ICD09
- 753.5 Exstrophy of urinary bladder
- 752.62 Epispadias
- 751.5 Other anomalies of intestine
- 751.2 Atresia and stenosis of large intestine, rectum, and anal canal
ICD10
- Q64.10 Exstrophy of urinary bladder, unspecified
- Q64.0 Epispadias
- Q64.12 Cloacal extrophy of urinary bladder
- Q42.3 Congenital absence, atresia and stenosis of anus without fistula
SNOMED
- 61758007 exstrophy of bladder sequence (disorder)
- 406476007 Epispadias (disorder)
- 20815007 Exstrophy of cloaca sequence (disorder)
- 204731006 Imperforate anus (disorder)
FAQ
- Q: Will the child have normal sexual function?
- A: Yes. Following a completed, successful repair, the sexual function will be normal.
- Q: Will the child be fertile?
- A: Females commonly achieve pregnancy without the need for in vitro fertilization. Males require in vitro fertilization to impregnate.
- Q: Can an exstrophy patient play sports?
- A: After successfully exstrophy closure, patients are able to play sports.
- Q: Is there risk of recurrence of bladder exstrophy in a family?
- A: Yes. There is a 1:100 chance for bladder exstrophy to recur in a family.