Introduction
Caring for patients with complex genitourinary anomalies can be challenging. These patients are anatomically complicated with nuanced disease processes. Here, we will focus on three common genitourinary anomalies: anorectal malformations, cloacal malformations, and genitourinary sinuses ( Box 25.1 ). These patients are closely followed in clinic; undergo multiple operative interventions; and face unique challenges when it comes to quality of life, bowel habits, urination, and sexual function and reproduction.
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Anorectal malformations
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Cloacal malformations: single outflow or common channel
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Urogenital sinus
Anorectal malformations and cloacal malformations
Overview and definition
Anorectal malformations (ARMs) occur along a wide spectrum in both boys and girls. Severity ranges from easily treated with good functional outcomes to severe, with other involved organ systems, a need for complex reconstruction, and poorer functional outcomes. Overall, a diagnosis of “anorectal malformation” is a buzzword. Understanding the anatomy underlying a patient’s individual diagnosis is key to understanding their functional status, future outcomes, and individual challenges and needs.
ARMs can be loosely divided into the following categories ( Figs. 25.1 and 25.2 ) :
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Imperforate anus without fistula (see Fig. 25.1 A): Absence of normal anal opening.
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Perineal fistula (see Fig. 25.1 B and Fig. 25.2 A): Abnormal anal opening outside of the sphincter muscle complex but within the perineum.
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Vestibular fistula (see Fig. 25.1 C and Fig. 25.2 B): Abnormal anal opening outside of the sphincter muscle complex within the vulvar vestibule of the female genitalia. Vestibular fistula is the most common female ARM.
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Vaginal fistula (see Fig. 25.1 C and Fig. 25.2 C): Abnormal anal opening outside of the sphincter muscle complex within the vagina.
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Cloacal malformation (see Fig. 25.1 D): Rectum, vagina, and urinary tract form a single outflow system (common channel) rather than three separate tracts; generally divided into long common channel (>3 cm) or short common channel (<3 cm).
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Rectal atresia: Normal anal canal with a stricture proximal to the dentate line.
ARMs occur in approximately 1 in 5000 live births. Historically, imperforate anus was the first described ARM. Classified in the early 18th century, surgeons were encouraged to divide the membrane theorized to be overlying the anal opening. Patients with low imperforate anus did well with this operation; patients with high imperforate anus did not. The operation for a high imperforate anus evolved over time. The modern approach, known as the posterior sagittal anorectoplasty (PSARP), was defined in 1980. This involves complete exposure of the anorectal region by incising all muscle structures behind the rectum. Colloquially referred to as a pull-through, the PSARP allows for the opportunity to restore continence in children with ARMs.
Etiology and pathophysiology
There are several theories regarding the etiology of ARM, but no one pinpointed cause. There are many associated congenital abnormalities, including trisomy 21, Currarino syndrome, and VACTERL associations (vertebral defects, anal atresia, cardiac defects, tracheo-esophageal fistula, renal anomalies, and limb abnormalities). These represent only about 11% of the population with ARM. Pathologically, an ARM is defined by an ectopic anus. One theory involves the development of the cloaca, a common channel that contains the urinary tract, female reproductive tract, and gastrointestinal tract. Around the seventh week of gestation, these structures separate. Abnormal development of the anorectal septum to separate these structures may lead to the formation of ARMs.
History and physical: Initial evaluation
Most patients with ARMs are diagnosed as newborns. A thorough physical examination is extremely critical, including a perineal examination and a complete examination to identify associated anomalies. Specifically, the anus should be identified as in the center of the sphincter complex. It must also be of appropriate size. If patients have concerning physical examination findings, surgeon evaluation is warranted, and an examination under anesthesia may be performed.
In females with concern for ARM, a close examination of the vulvar vestibule and vagina should also be performed, as this can help identify the presence of a rectovestibular fistula, rectovaginal fistula, or other vaginal malformation (i.e., distal vaginal atresia). This examination can be performed using a labial traction to fully visualize the vestibule (see chapter 4 , Figure 4.1 and 2.2) and, in some cases, vaginoscopy to examine the vagina. Often an examination under anesthesia is combined with cysto-vaginoscopy. This affords the opportunity to understand the type of ARM and the patient’s unique anatomy—including the relationship between the urethra, vagina, and rectum; the length of the common channel (in cloaca malformations); and the number of cervices present (zero, one, or two). This information helps preoperative surgical planning.
A minority of ARMs can be diagnosed prenatally, often because of the presence of other associated anomalies. This may facilitate delivery in a specialized center and more appropriate predelivery counseling for patients and families.
Because of the high coincidence of chromosomal abnormalities and syndromes, especially with VACTERL abnormalities, patients diagnosed with ARM should undergo a thorough workup for these associated symptoms ( Table 25.1 ). Additionally, the sacral ratio should be calculated via sacral radiograph images, as this may provide prognostic information for future continence.
| Involved Organ System | Examples | Workup |
|---|---|---|
| Vertebral |
|
|
| Anus | Imperforate anus | Physical examination |
| Cardiac |
| Cardiac echocardiography |
| TE (trachea/esophagus) |
|
|
| Renal | Horseshoe kidney | Renal ultrasound |
| Limb | Radial hypoplasia | Limb x-rays |
Management
Management of ARMs depends on the health of the child and the type of ARM. 
In unstable patients, urgent operation may be warranted regardless of the child’s associated comorbidities; in stable patients, full assessment may help optimize for surgical intervention.
The major surgical decision is to pursue a primary operation, with an early pull-through, or delayed operation, with an early colostomy and delayed pull-through. Indications for a colostomy and delayed primary repair include a flat perineum, meconium in the urine, distal gas high above the pelvis, and cloaca. The initial colostomy decompresses stool; a mucous fistula is also created with the proximal end of the distal colon to decompress the distal end. The goal in this initial operation is to create two stomas—the colostomy should ideally be of the descending colon, and the mucous fistula small and as far as possible from the colostomy. A key component of early management of cloaca malformations is protection of the kidneys. The presence of hydrocolpos can affect renal function, and a renal ultrasound is used to evaluate for hydronephrosis and/or hydroureter. Decompression of the hydrocolpos and subsequent improvement of hydronephrosis can be performed via clean intermittent catheterization via the common channel or vaginostomy.
Definitive surgical management with a “pull-through” procedure varies based on the type of ARM. Most operations begin with an examination under anesthesia, which allows the provider opportunity to identify anatomy. Operative choice then depends on the malformation type ( Table 25.2 ). Pull-through may or may not be done with an ostomy for protection at the same time. If not previously performed, a thorough assessment of the female reproductive tract is necessary to accurately determine anatomy. Vaginoscopy provides information on the presence or absence of a longitudinal vaginal septum and number of cervices, which helps understand the müllerian anatomy. Additionally, an inspection of müllerian structures via laparoscopy or at the time of other abdominal procedures allows accurate assessment of the upper reproductive tract. 
The likelihood of an associated gynecologic anomaly increases with the complexity of the ARM (rectoperineal fistula 5%, rectovestibular fistula 18%, cloacal malformation 68%). Understanding the upper reproductive tract anatomy, lower reproductive tract anatomy, and the relationship to the urinary and colorectal tracts optimizes preoperative reconstructive planning and aids in anticipatory guidance and counseling for patients and families.
| Intervention | Population | Description |
|---|---|---|
| Posterior sagittal anorectoplasty (PSARP) | Rectoperineal fistula | Posterior sagittal incision, mobilization of rectum, and transposition/placement within the sphincter complex |
| Posterior sagittal anorectoplasty (PSARP) | Rectovestibular fistula and imperforate anus without fistula | Generation of two walls between the rectum and the urethra via separation of the common septum in addition to traditional PSARP |
| Posterior sagittal anorectal-vaginal-urethral-plasty (PSARVUP) | Cloacal malformation <3 cm | Posterior sagittal approach as in the PSARP followed by mobilization of the vagina and urethra together with eventual separation |
| PSARVUP with laparotomy or laparoscopy | Cloacal malformation >3 cm | PSARVUP with additional maneuvers to ensure adequate length of the urethra and the vagina to the perineum if anatomically feasible; may include creation of a neovagina (using a bowel graft) |
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