The incomplete cloaca and Bardet-Biedl syndrome: A remarkable association with broader implications on patient's care

Incomplete cloaca is a rare cloacal variant that refers to a persistent urogenital sinus in girls with the bowel opening anteriorly in the perineum or the vestibule (summary figure). Most of these girls present primarily to pediatric surgeons/urologists as neonatal hydrocolpos. This study outlines the diagnosis and management of this condition while highlighting its association with Bardet-Biedl syndrome (BBS). The latter is a genetically heterogenous group of autosomal recessive disorders characterised by multisystem affection: pigmentary retinopathy, obesity, mental defect, polydactyly, genitourinary abnormalities, and parenchymatous kidney disease.

A prospectively maintained database (2007 through 2024) of Anorectal anomalies and allied conditions was queried for cases of incomplete cloaca. We identified 5 girls all presenting primarily with neonatal hydrocolpos and postaxial polydactyly. Comprehensive clinical, radiological, and surgical data were gathered. Although BBS was not initially recognized, follow-up evaluations revealed features indicative of BBS, prompting further ophthalmological, renal, and cognitive assessment.

Pelvic imaging and lower panendoscopy confirmed the anatomical findings consistent with the diagnosis. Surgical management involved a staged approach, with initial urogenital decompression (3/5), followed by definitive reconstruction using a combined abdominoperineal (2/3) or pure perineal approach (1/3). In the remaining two, a one-stage correction was possible after successful clean intermittent catheterisation of the vagina with urogenital mobilization in one and laparoscopic-assisted vaginal pull-through in the other. Limited sagittal anorectoplasty was performed in 3/5 cases to correct the symptomatic anterior anorectal displacement. Four girls were available for follow up (median 6 years). During the initial evaluation, the association with BBS was not recognized, as polydactyly was attributed to the known limb anomalies accompanying anorectal malformations. With the evolving clinical update, the clinical diagnosis of BBS was established in 3 cases. The remaining patients, one had polydactyly and obesity but was lost to follow-up while the other did not exhibit further cardinal features of BBS and assumed to have McKusick-Kaufman syndrome.

This case series illustrates the significant association between incomplete cloaca and BBS. Postaxial polydactyly and obesity are important clues for the possible syndromic association. Pediatric surgeons/urologists need to be aware of this association and promptly refer these girls to the appropriate multidisciplinary specialties to assure an expedient management and support for these girls and their families as they navigate the challenges associated with this syndrome.

This is a case series.

Level IV evidence.