Posterior cloaca—further experience and guidelines for the
treatment of an unusual anorectal malformation
, Andrea Bischoff, Lesley Breech, Emily Louden, Marc A. Levitt
The Colorectal Center for Children, Division of Pediatric Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati,
OH 45229-3039, USA
Received 16 February 2010; accepted 23 February 2010
Urogenital sinus with
Introduction: The term posterior cloaca refers to a malformation in which the urethra and vagina are
fused, forming a urogenital sinus that deviates posteriorly to open in the anterior rectal wall or
immediately anterior to the anus.
Methods: A retrospective review of 411 patients diagnosed with cloaca was performed to identify the
ones with a posterior cloaca. Special emphasis was placed on anatomy, diagnosis, associated anomalies,
and outcome in terms of urinary and fecal continence. Surgical treatment was a total urogenital
mobilization with a transrectal approach.
Results: Twenty-nine patients were diagnosed with a posterior cloaca. Of these, 15 had a single orifice
at the normal location of the anus with the urogenital sinus opening in the anterior rectal wall. Fourteen
had the urogenital sinus opening immediately anterior to the normally located anal opening (2 orifices),
which we considered a posterior cloaca variant. Nineteen patients (65%) had hydrocolpos. Twenty-
seven patients (93%) had associated urologic anomalies, 12 patients (41%) had gynecologic anomalies,
and vertebral malformations occurred in 41% of cases. Other anomalies included gastrointestinal
(7 patients), cardiac (5), and tethered cord (2). Late diagnosis occurred in 2 patients. Twenty patients
were available for long-term follow-up: 17 are fecally continent, 3 are fecally incontinent, 11 are urinary
continent, 5 are dry with intermittent catheterization, and 4 have dribble urine.
Conclusion: The most important characteristic of the posterior cloaca is the high frequency of a normal
anus, which differentiates this malformation from the classic cloaca. Often, many associated
malformations are present and therefore should be suspected and diagnosed. The main goal during
the operation should be to not mobilize the anus and thereby preserve the anal canal. A total urogenital
mobilization, transperineally or with a transanorectal approach, is ideal for the repair.
© 2010 Elsevier Inc. All rights reserved.
In a typical cloaca, the urethra, vagina, and rectum are
fused, forming a common channel that opens as a single
orifice in the perineum at the site where the urethra would
normally be located . We use the term posterior cloaca to
refer to a malformation in which the urethra and vagina
are fused, forming a urogenital sinus that is posteriorly
deviated and opens in or immediately anterior to the rectal
wall (Figs. 1-4) [2,3].
The most relevant difference between a typical cloaca and
the posterior cloaca is that, in the latter, the anus is normally
located and has a pectinate line. This means that the anal canal
Corresponding author. Tel.: +1 513 636 3238; fax: +1 513 636 3248.
E-mail address: email@example.com (A. Peña).
0022-3468/$ – see front matter © 2010 Elsevier Inc. All rights reserved.
Journal of Pediatric Surgery (2010) 45, 1234–1240