Cloaca: Podcast

Pediatric Surgery
Marc Levitt, MD discusses Cloaca with Todd Ponsky, MD and Aaron Garrison, MD
Edited by Ian C Glenn, MD and Sophia Abdulhai, MD

Dr. Levitt is surgical director of the Center for Colorectal and Pelvic Reconstruction as well as program director of the Pediatric Colorectal, Pediatric Colorectal Research, and Pediatric Pelvic Reconstruction fellowships at Nationwide Children's Hospital in Columbus, Ohio.

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What’s New in Cloaca

 

Prenatal evaluation

  • Concerning fetal features
    • Pelvic mass on US (which is the most common finding), which may represent a dilated vagina (hydrocolpos)
    • Bilateral hydrocolpos
    • Missing radius
    • Absent sacrum
    • Single kidney or hydronephrosis
  • MRI
    • It is common for patients with abnormal US to be referred for MRI

Prenatal discussion

  • Unlike most anorectal malformations, cloaca, or suspected cloaca, is one of the few which may be identified prenatally.
  • There are very few situations where fetal surgery is indicated.
  • Early delivery is rarely indicated.

Neonatal management

  • Imaging
  • Colostomy creation
  • Hydrocolpos drainage, if needed
  • Co-management with pediatric urology

Initial neonatal evaluation

  • One, two, or three orifices?
  • Are the orifices properly located?
  • Cloaca has one orifice immediately inferior to the clitoris
  • If there are two orifices, it most likely represents a urogenital sinus
  • Urethra and improperly located anus may represent a vestibular fistula with absent vagina
  • In females, the most common ARM has three orifices, representing a vestibular fistula or perineal fistula.

Tips for physical exam

  • Good lighting
  • Grab the labia and pull up and out, in order to accentuate the single orifice. If the patient indeed has a cloaca, only one structure will be visible. If three structures are visible (urethra, vagina, and another opening), this is a vestibular fistula.

Workup for cloaca

  • Diagnosis is mainly clinical
  • Abdominal and pelvic ultrasound to evaluate for solitary kidney, hydronephrosis, and hydrocolpos.
  • Spinal US to evaluate for tethered cord
  • Echocardiogram
  • X-ray of the spine

Management of hydrocolpos

  • May be drained by interventional radiology, or may be addressed operatively (usually during colostomy creation).
  • Initial consideration should be given to passing a catheter into the perineal orifice to attempt to decompress the hydrocolpos. However, the catheter is not easily directed and may terminate in the urethra, rectum, or either hemi-vagina.
  • If intermittent catheterization consistently "works”, it should be confirmed by ultrasound that it is actually working (in order to prevent hydronephrosis).

Hydrocolpos drainage (aka vaginostomy) pearls

  • The ideal time to drain the hydrocolpos is during colostomy creation
  • It is imperative to determine if there is a hemivagina and/or bilateral hydrocolpos.
  • If there is bilateral hydrocolpos, get to the dome of the vaginas and remove part of the vaginal septum. Then, one tube may be used to drain both sides.
  • The vaginostomy tube is brought out of the RLQ with the colostomy on the left side.
  • If the hydrocolpos is large enough to be above the umbilicus, the vaginostomy tube may be sewn into the RLQ, similar to a gastrostomy tube.
    • In these cases, the vaginostomy tube may ultimately be removed and it will either drain spontaneously, or maybe intermittently catheterized.
  • Dr. Levitt’s tube of choice is an 8- or 10-French pigtail catheter. The problem with straight catheters, is that as the hydrocolpos begins to recede from the abdominal wall, the tube is more likely to be displaced.
  • Ultrasound should be obtained on post-operative day 1 or 2 to monitor for improvement of hydronephrosis. Complete resolution of hydronephrosis may take weeks, but the US should demonstrate that the hydronephrosis is not worsening and that all structures are adequately decompressed. Furthermore, the patient should have adequate urine output.

Role of vesicostomy

  • The purpose of vesicostomy is to drain the bladder and the problem with these patients is typically not the bladder. In fact, the hydrocolpos typically compresses the trigone of the bladder (and consequently compresses the distal ureters). Thus, the ureters are not able to empty into the bladder and drainage of the bladder would not help.
  • If the hydrocolpos is successfully drained, and the hydronpehrosis persists, a suprapubic tube or vesicostomy is indicated. This is very rare and is typically seen with a very narrow common channel or with complete absence of the urethra.
  • Bladder decompression is also indicated in cases of massive, bilateral ureteral reflux.

Etiology of hydrocolpos

  • Ineffective bladder drainage via the common channel, with preferential drainage of urine into the vagina.
  • Accumulation of vaginal mucous, which is influenced by high maternal estrogen levels
  • It is incompletely understood why the vagina does not spontaneously drain, even though there is not typically a mechanical obstruction.

Role of cystoscopy

  • There is no need for routine cystoscopy in the neonatal period.

Initial operative approach options

  • Laparoscopic hydrocolpos drainage with colostomy creation
  • Open technique utilizing a LLQ oblique incision
  • For patients with massive hydrocolpos (extending above the umbilicus), a lower midline incision is preferred. Then, a tubeless vaginostomy may be performed and both stomas can be brought out of one of the lower quadrants without a skin bridge.

Management of urogenital sinus

  • The rectum is rarely involved.
  • Patient needs lab work to evaluate for electrolyte abnormalities
  • If the urine does not spontaneously drain, a drainage procedure is indicated.
  • Definitive surgery is often performed by pediatric urology. If a very high urogenital sinus is involved, a transrectal approach may be indicated. Otherwise, a perineal approach is used.
  • The definitive repair is performed in an elective fashion.

Timing of definitive cloaca repair

  • Repair is performed electively.
  • Endoscopy, cystoscopy, vaginoscopy, and cloacagram are typically performed in the same setting at 2-3 months of age.
  • Formal repair typically takes place after this, usually by 6 months of age and certainly prior to the patient’s first birthday.

Imaging

  • Endoscopy is performed via the common channel and is used to identify the length of the common channel.
  • Cystoscopy determines the length of the urethra.
  • Difficult cases or predicted by common channel length greater than 3 cm or urethral takeoff from the bladder neck less than 1.5 cm.
  • Vaginoscopy demonstrates if there are one or two vaginas and how surgically accessible they will be.
  • The cloacagram helps to determine the length and relative position of the rectum. This requires a contrast study, with injection of contrast through the common channel and colostomy. If a vaginostomy and/or vesicostomy are present, contrast may be injected via these as well.
  • Contrast injection may be aided by placing temporary catheters into the bladder, colostomy, and perineal orifice, with subsequent injection of contrast through these catheters.
  • The lateral image is the most important, as it demonstrates the position of the rectum, vagina(s), and urethra.

Role of 3D printing and imaging

  • Emerging technology which may help in pre-operative planning, particularly for very complex cases.
  • The long term practicality and feasibility of this is unclear.

Collaborative approach to repair

  • Surgical help may be provided by urology and gynecology
  • Pediatrics team can help with management of renal function
  • Interventional radiology for possible drainage of hydrocolpos

Surgical repair

  • While any pediatric surgeon can perform the colostomy and drain the hydrocolpos, a decision must be made about the need for referral for definitive cloaca repair.
  • Urogenital mobilization is performed (i.e. mobilization of the rectum in the traditional way, akin to management of vestibular fistula, with subsequent mobilization of the urethra and vagina as a unit). In other words, do not operate on the wall between the urethra and vagina.
  • Difficult cases or predicted by common channel length greater than 3 cm or urethral takeoff from the bladder neck less than 1.5 cm.
  • Patients with inadequate urethral length are those who may benefit from referral to a more specialized center. These patients should not undergo urogenital mobilization. The common channel will ultimately be used to form the neo-urethra and the vagina must be separated from the common channel.
  • A patient with a short common channel (e.g. 1 cm) with adequate length urethra to the bladder neck only needs mobilization of the vagina and the urethra may be left alone. These patients will be able to void normally.

What if the vagina doesn’t reach?

  • Not an uncommon occurrence in patients with higher cloacas.
  • Vaginal switch
    • Disconnect one of the sides of the vagina (while being sure to preserve the ovarian blood supply) and swing the dome of the vagina down, with removal of the vaginal septum.
  • Interposition
    • The uterus is left in place and the vagina is bridge to the perineum.
    • Rectum, colon, or small bowel is used as the bridging structure. Dr. Levitt prefers to use the left or sigmoid colon.
  • Tissue engineering of vagina

Pitfalls 

  • The most common problem after cloacal repair is when the cloaca is inadequately recognized, and only rectal repair was performed. The second most common mistake is inadequate mobilization of relevant structures.

Contact information for Dr. Levitt

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