INTRODUCTION
Cloacal exstrophy is the most severe anomaly in the spectrum of the extrophy-epispadias complex. It is extremely rare, occurring in approximately 1 in 200,000 to 400,000 live births, and males are affect- ed twice as often as females.
With advance in prenatal diagnosis, more patients are now diagnosed on prenatal scans. The criteria in- clude non-visualization of the bladder, a large mid- line infraumbilical anterior wall defect or cystic ante- rior wall structure (persistent cloacal membrane), omphalocele and lumbosacral anomalies. Seven less frequent or minor criteria namely lower extremity defects, renal anomalies, ascites, widened pubic arch- es, a narrow thorax, hydrocephalus and one umbilical artery have been described.
The exact embryology is still debated but the de- fect results from abnormal mesodermal migration during development of the lower abdominal wall and of the urogenital and anorectal canals.
Associated anomalies are common in the urinary tract, pelvic kidney and renal agenesis are seen in a third of all patients. Spinal dysraphism is present in about 67% of patients and is associated with a signif- icant morbidity. Skeletal system anomalies of both the vertebral bodies and the lower limbs are com- monly seen.
In girls duplication of the uterus and vagina are common. In the males the incidence of bilateral crypt- orchidism is high but in some the testes have de- scended. These testes are normal on histology.
Exomphalos is seen in about 85% of patients and sometimes gastrointestinal (GI) tract abnormalities like malrotation, duplication and duodenal atresia may be present.
Short gut is seen in about 25–50% of all patients and, consequently, impaired growth is observed in a significant number of patients and appears to occur before any major reconstruction. Fifty percent of the infants in the Great Ormond Street Hospital series were below the 3rd centile for weight at 1 year of age.
Cloacal exstrophy should be managed in a special- ist centre by a multidisciplinary team comprising a pediatric urologist, pediatric surgeon, neonatologist, pediatric neurosurgeon and a pediatric orthopedic surgeon with a special interest in the management of these complex anomalies. The role of the pediatric urology nurse specialist and a psychologist is invalu- able in the long-term management of these patients.
The surgical repair includes reconstruction of the bladder and genitalia. Conservation of all bowel seg- ments to minimize fluid and electrolyte losses and for further genito-urinary tract reconstruction. Soft tissue mobilization and/or osteotomies.
Transfer of the neonate to a specialist centre must be arranged. A cling-film dressing should be used to cover the exposed bladder plate and the hindgut.
This minimizes fluid losses and reduces mucosal damage. The umbilical cord should be ligated with a nonabsorbable suture to prevent the umbilical clamp abrading the bladder plate or the hindgut.
Intravenous access should be obtained in the upper limbs. Routine pre-operative bloods including a karyotype should be drawn.
Renal and spinal tract ultrasounds are necessary to document any upper tract abnormalities and spi- nal cord tethering. A distal loopogram is recom- mended by some centres to assess colonic length.
Duncan Wilcox, Manoj Shenoy
Figure 57.1
Anatomically, the foreshortened hindgut or caecum is seen between the two hemibladders. The orifice of the terminal ileum, rudimentary hindgut and appen- dix are seen on the caecal surface. The ileum may be prolapsed. The pubic symphysis is widely separated and the hips are externally rotated and abducted. The phallus is separated into right and left halfes with the adjacent labium or scrotal half. Superiorly there is an exomphalos containing small bowel and sometimes liver. There is a large intra-patient variation and a classification system has been proposed.
The size of the exomphalos and the hindgut plate largely determine the extent of the initial closure.
The order of the repair is closure of the exomphalos followed by separation of the hemibladders from the hindgut plate and GI reconstruction and then blad- der closure. The exomphalos closure is not always possible and a silo may be required in some cases.
Figure 57.2
Two 5F ureteric catheters are placed in the two ure- teric orifices and secured with 5/0 absorbable su- tures. Dissection commences first superiorly and the umbilical vessels are doubly ligated and divided. The extrophied section is separated from the skin and the adjacent hindgut with diathermy taking care to avoid the ureters, which can be felt medially once the stents are inserted. The two hemi-bladders are then separ- ated from the exstrophied hindgut.
Once this is performed, the length of the available hindgut is measured and the exstrophied hindgut is tubularised to recreate the ileo-colonic valve. The ter- minal part of the colon is fashioned into a colostomy.
The appendix, where possible, is preserved.
The two hemibladders are approximated and the bladder is closed according to standard principles applied for primary bladder exstrophy closure. The urethra is tubularized over an 8F catheter, either completely (in girls) or partially (in boys).
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Figure 57.3
The abdominal wall is closed in layers with inter- rupted 3/0 absorbable sutures.
The pubic symphysis is approximated with a 0/0 suture. Osteotomies may be performed to assist clo-
sure. Skin closure with subcuticular 5/0 absorbable suture and the stents are brought out through the su- ture line.
Prolapsed intestine Omphalocele
Half bladder Half bladder
Figure 57.1 Figure 57.2
Figure 57.3
CONCLUSION
The majority of patients with cloacal exstrophy now survive with advances in perinatal management and surgical reconstruction. The emphasis has shifted from trying to achieve survival to providing a better quality of life to patients in the long-term.
The reconstruction of the urinary tract takes pri- ority after the initial reconstruction. The timing var- ies with each individual patient. Initial continence rates were reported as about 5% in males and 10–15%
in females.
Husmann reported in 1999 that even with staged reconstruction only 22% patients achieved conti- nence. The presence of an associated neurological abnormality significantly affected the ability to achieve continence – 7% of those with neurological abnormality achieved continence compared to 40%
of those without one. Those with low detrusor leak point pressure underwent bladder neck closure and Mitrofanoff channel construction. Overall conti- nence was achieved in 48% of patients who under- went staged reconstruction, 22% after bladder neck reconstruction and 26% after a second procedure, in- cluding the Mitrofanoff principle with bladderneck closure. Noncontinent diversion was used to manage persistent incontinence in 22% of patients. However, 30% of them remained dependent on diapers.
He suggested that all patients have detailed neuro- logical assessment; following this those with an intact spine should undergo staged reconstruction; those with an associated neurological abnormality should have a continent catheterizable stoma formed.
In the Great Ormond Street series, of the 19 pa- tients reviewed, five patients had renal deterioration, two had pre-existing dysfunction, two deteriorated following bladder neck reconstruction and reim- plant, and one patient deteriorated following blad- derneck closure and re-implant. Bladderneck closure itself does not increase the risk for renal deteriora- tion but close follow-up is mandatory following re- implantation to avoid renal deterioration.
A considerable proportion of patients have mor- bidity related to both GI tract and the spinal dys- raphism and due attention should be paid to treat the bowel dysfunction. There was no difference in the growth velocity of patients who underwent terminal ileostomy compared with those who had terminal colostomy in the long-term follow-up though the for- mer required more days in hospital and hyperali- mentation usage during the first year of life. The hindgut has been used for terminal colostomy with anal pull-through if a solid stool can be produced. In a select group anterior sagittal anoproctoplasty may be used to achieve this. In a series of 25 patients re- ported by Peña over a 23-year period, eight patients had a PSARP and 17 an anterior sagittal ASARP.
Three were completely continent and four soiled oc- casionally. A total of 11 patients were continent with a bowel management program. Four were incontinent and were candidates for a bowel management pro- gramme, and two were incontinent and converted to an ileostomy. One patient was incontinent and re- fused a bowel management programme.
The decisions about gender reassignment are limit- ed to the male patients with cloacal exstrophy and one is faced with the ultimate challenge of deciding wheth- er those children who have XY chromosomes would fare better with abnormal or absent genitalia, or recon- struction in a reassigned gender. The testicular hor- mone has an important role in sexual differentiation of the mammalian brain and behaviour and no prena- tal hormonal abnormality has been reported.
The experience at Great Ormond Street with cloa- cal exstrophy patients of XY chromosomes reas- signed to the female gender has shown that they have female-type core gender identity but appear to dem- onstrate masculine childhood role behaviour-prefer- ence for toys like vehicles over dolls and an interest in athletic activity.
In male patients with cloacal exstrophy when con- version to a female gender is considered, reduction phalloplasty is not an issue as the penis is usually small. The real surgical issue is bilateral orchidecto- my because if testes remain masculinization contin- ues and if they are removed the potential for fertility is lost. No documentation of paternity exists. Infertil- ity or subfertility could be multifactorial and result from cryptorchidism, retrograde ejaculation due to an incompetent bladderneck, dysfunctional bulbo- spongiosus muscle action, erectile dysfunction due to dissection of the corpora of the ischiopubic ramus, recurrent epididymo-orchitis, vasal or seminal tract injury during surgery. Myelodysplasia may also be a contributory factor.
In patients with cloacal exstrophy studied at Great Ormond Street, little difference was seen to exist in the quality of life between those raised as females, whether they were with an XY or XX karyotype. They appeared similar in social relationship with family and peers, and satisfaction with leisure and recrea- tional activity. They disliked their colostomy and the need to perform catheterization but regarded the overall quality of life to be high.
Psychological well-being and stable gender identi- ty are paramount when considering the quality of life for patients with cloacal exstrophy. Presently, there is insufficient information to make informed decision about optimal gender assignment in those with XY chromosomes. Until objective evidence becomes available, no firm approach could be advocated, and care needs to be individualized.
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SELECTED BIBLIOGRAPHY
Gearhart JP, Jeffs RD (1992) Exstrophy of the bladder, epispadi- as and other bladder anomalies. In: Walsh PC, Retik AB, Stamey TA, Vaughan ED (eds) Campbell’s urology, 6th edn, vol 2. WB Saunders , Philadelphia, Chap 46, pp 1772–1815 Groner JI, Ziegler MM (2003) Cloacal exstrophy In: Puri P (ed)
Newborn surgery. Arnold, London pp 629–636
Husmann DA, Vandersteen DR, McLorie GA et al. (1999) Uri- nary continence after staged bladder reconstruction for cloacal exstrophy: the effect of coexisting neurological ab- normalities on urinary continence. J Urol 161 : 1598
Peña A (2000) New concepts in bowel reconstruction in cloa- cal exstrophy. Dialogue Pediatr Urol 23:3
Schober JM, Carmichael PA, Hines M, Ransley PG (2002) The ultimate challenge of cloacal exstrophy. J Urol 167 :300–304
