Cloacal Exstrophy Repair

Abstract

Cloacal exstrophy is a birth defect in which part of the abdomen is open, and some of the abdominal contents (such as the bladder and intestines) are exposed. It is the most severe birth defect within the exstrophy-epispadias complex and can occur as part of the OEIS complex, which is characterized by omphalocele, exstrophy, imperforate anus, and spinal defects. It is a rare congenital malformation, occurring in 1/200,000-400,000 births, and is diagnosed by prenatal ultrasound. In cloacal exstrophy, there are two exstrophied hemibladders separated by a foreshortened cecum or hindgut, often characterized by a blind end, resulting in an imperforate anus. There is significant diastasis of the pubic symphysis, and the phallus is separated into two halves along with the scrotum. In males, the penis is usually flat and short, with the exposed inner surface of the urethra on top, and split into a right and left half. In females, the clitoris is split and there may be two vaginal openings. This condition is also highly associated with other birth defects, especially spina bifida, which coexists in up to 75% of cases. Multidisciplinary care followed by surgical management should begin immediately following the birth of the patient. Closure of the meningocele and omphalocele, as well as adaptation of the bladder halves, should be started in the neonatal period, followed by a multi-stage approach for bladder, bowel, and genital reconstruction (including a pelvic osteotomy) at a later time. Here, we present a patient who was diagnosed with cloacal exstrophy by prenatal ultrasound. The urinary bladder and intestines were noted to be outside of the body and associated with a closed myelomeningocele. The exstrophied cloaca was repaired and reduced back into the abdominal cavity. Urinary and fecal diversions were created, and a leg casting was placed for pelvic osteotomy.

Keywords

abdominal wall; abnormalities; omphalocele; bladder; urogenital

Case Overview

Background

Cloacal exstrophy occurs in about 1/200,000–400,000 live births.¹ The term cloaca refers to the pelvic malformation in which there is the confluence of urinary, genital, and gastrointestinal tracts.² Cloacal exstrophy is the most severe variant of a spectrum of disorders that develops from the inappropriate bridging of the cloacal membrane and urogenital septum. These disorders have been termed the exstrophy-epispadias complex (EEC). In addition to cloacal exstrophy, the other two disorders of the EEC are bladder exstrophy and epispadias, listed in order of decreasing severity. In addition, cloacal exstrophy can occur as part of the omphalocele, exstrophic cloaca, imperforate anus, and spinal defect (OEIS) complex, which is present in this case.³ 

In cloacal exstrophy, the cecal plate and hemibladders are inappropriately attached to the skin and muscle of the abdominal wall. The repair involves detaching the cecal plate from the abdominal wall, and then reducing the intestine and hemibladders into the abdomen. The intestine leads to a blind end with an imperforate anus, which is resolved by suturing the intestine into an ostomy to divert feces to the skin surface. 

Focused History of the Patient

Cloacal exstrophy was identified during a prenatal ultrasound. This infant had all four major criteria used for identifying cloacal exstrophy. The major criteria are nonvisualization of the bladder, a large midline infraumbilical anterior wall defect or cystic anterior wall structure (persistent cloacal membrane), omphalocele, and lumbosacral anomalies. Minor criteria that are more scarcely present include lower extremity defects (club feet present in this infant), renal anomalies, ascites, widened pubic arches, a narrow thorax, hydrocephalus, and one umbilical artery.⁴ When prenatal ultrasound is nondiagnostic, fetal MRI may clarify the diagnosis of cloacal exstrophy and aid in prenatal planning.⁵

Physical Exam

The patient is a male neonate presenting with the OEIS complex. He has a prolapsed terminal ileum through an omphalocele, which has the appearance of an “elephant trunk.” Umbilicus is absent. Genitalia consists of a split hemiscrotum and a rudimentary phallus covered by a urethral plate. The anus is imperforate, and the feet are clubbed bilaterally.

Imaging

Plain films, CT, or MRI of the patient, to be uploaded separately from the text.

Natural History

Cloacal exstrophy results from the failure of migration of the lateral mesodermal folds. It has variable presentations depending on the stage of the infant’s development that the failure occurs in. The failure of migration prevents normal mesodermal ingrowth to the cloacal membrane. This results in an ill-supported membrane causing premature rupture, which results in varying severities of abdominal wall defect. This migration failure most likely occurs within the first 8 weeks of gestation.⁶

Options for Treatment

Standard treatment for cloacal exstrophy is an urgent surgical repair of the omphalocele within the first days after birth. Early intervention prevents the inevitable onset of sepsis and nutritional deficits that would be life-threatening to an infant who went without surgical intervention. In recent years, the treatment of cloacal exstrophy has improved to become a consideration of the quality of life rather than a question of saving a life.⁷ 

Historically, the two most common surgical approaches have been a one-staged approach and a multi-staged approach. Recently, Jayman et al. demonstrated the odds of having a successful closure are 3.7 times greater for the multi-staged approach compared with the one-staged approach.⁸

Rationale for Treatment

The initial goal of surgical intervention is to create safe bowel and bladder outlets to prevent infection and preserve tissue. An early concern in infants is the onset of sepsis, and a more farsighted concern is to save as much bladder and intestine as possible while closing the omphalocele to maximize bladder growth and intestinal absorption potential for when an ileostomy or colostomy is placed at a later time. Colon preservation is of the utmost importance for maximizing the infant’s potential for electrolyte absorption and stool continence.⁹    

In a multi-staged surgical repair, the first stage of surgical intervention is performed neonatally and consists of an omphalocele repair, separation of the hindgut, approximation of bladder plate, and canalization of cecum into an ostomy.¹⁰ 

After the cecum and bladder are detached from the abdominal wall, the cecum is canalized via suturing to form a tube that drains into an ostomy on the surface of the skin. The bladder tissue is also mobilized and sutured off to form a functional bladder, which will have a catheter draining to the skin’s surface. Intervention at a later time will address methods to gain urinary continence.   

Discussion

Prior to the development of surgical techniques to repair the abdominal malformations of OEIS syndrome, cloacal exstrophy was a fatal condition.¹¹ Current survival rates range from 98–100%.^2,12 Jayman et al. have shown a 100% success rate through 34 cases of closing the cloacal exstrophy successfully on the first attempt by using a dual-staged pathway.¹⁰ The multi-staged pathway has exhibited improved success rates by delaying the closure of the bladder, which allows the infant to develop better nutritional status and to grow more bladder tissue before relocating the bladder deep into the pelvis.¹⁰ 

Recent studies have demonstrated technique modifications that improve outcomes and are the current standard of care. In this case, a pubic symphysis stitch was used to decrease the tension put on the abdominal wall sutures following the repair of the omphalocele. The complication rates of the first surgical stage can be decreased from 89 to 17% by decreasing the diastasis of the anterior pubic rami to prevent dehiscence.¹³ 

Additional techniques include postoperative immobilization with external fixation using modified Buck’s traction for 6–8 weeks, when an osteotomy will be performed to approximate the pubic rami. If an osteotomy will not be performed, postoperative immobilization with modified Bryant’s traction for 4–6 weeks was most effective.¹⁴ In patients having an osteotomy performed, pediatric orthopedic surgeons were shown to have success rates significantly higher than general orthopedic surgeons.¹⁵ 

The second stage includes closure and placement of the bladder deep into the pelvis, followed by an abdominal wall closure. 2–3 weeks prior to abdominal wall closure and deep placement of the bladder, the first stage of osteotomy is often performed to prevent dehiscence once deep bladder placement occurs. Infants with a diastasis measurement greater than 4 cm undergo a staged osteotomy, rather than an osteotomy performed on the same day as the bladder closure.¹⁰ 

A significant factor for gaining urinary continence is the success of the initial surgical formation of the bladder.¹⁷ In 2018, Maruf et al. demonstrated that urinary continence could be gained in 71% of patients with cloacal exstrophy who underwent additional procedures to gain continence.¹⁸ The median number of additional procedures for urinary continence following the initial bladder closing procedure was 2 (range 1–4), and the median age of attainment was 11 years.¹⁸ A 1989 series by Mitchell et al. demonstrated that all 10 patients who underwent bladder reconstruction to gain continence were able to stay dry for periods of 3 or more hours through the use of a continent stoma and clean intermittent catheterization, and 50% were totally dry during both day and night.¹⁹ Clean intermittent catheterization was required of all patients in the study except one.¹⁹

In addition to bladder continence, intestinal continence can be gained. Although it was once thought that all patients with an exstrophic cloaca would require a permanent stoma for passing bowels, a 2008 study of 20 patients born with cloacal exstrophy and treated with a colonic pull-through indicated that 17 (85%) of the patients were clean with bowel management at the time of follow up.¹⁶ Another benefit of the colonic pull-through is the maximization of colonic tissue for increased nutrient absorption and the formation of solid stool. 

Historically, different factors have contributed to assigning gender to 46XY infants with cloacal exstrophy and ambiguous genitalia. In a 2011 study of gender assignment for newborns with 46XY cloacal exstrophy completed by fellows in the Urology Section of the American Academy of Pediatrics, 79% of fellows favored male gender assignment, with the most important factor in male assignment being androgen brain imprinting.²⁰ Of the fellows who selected female assignment as most appropriate, the factors cited as important in their decision making were the high likelihood of functional female genitalia and the uncertain results of male phalloplasty.²⁰ The perspectives regarding gender assignment have morphed over time. In a review of patients from 1974 to 1992, 12 of 13 genetic males treated for cloacal exstrophy were given the female gender.² Whether a patient’s gender is reassigned or not, it has been recommended that all patients with cloacal exstrophy undergo long-term psychological counseling to cope with issues such as dating, sexuality, marriage, and depression.²¹

Equipment

5-0 Vicryl chromic, 

Disclosures

Nothing to disclose.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.