Urorectal septum malformation sequence: A report of seven cases

Abstract

Urorectal septum malformation (URSM) sequence is an extremely uncommon anomaly. We report herein seven cases of URSM sequence that were identified after reviewing all autopsies conducted at our hospital over a period of 26 years (1981-2006). The URSM spectrum includes partial and full URSM sequences. Absent perineal and anal openings with ambiguous genitalia are included under 'full URSM sequence', and a single perineal or anal opening draining a common cloaca with an imperforate anus is called 'partial URSM sequence'. Of our seven cases of URSM, three were full URSM sequence and four were partial URSM sequence. Associated renal anomalies were found in all of the cases. Three cases had unilateral renal agenesis and one each had bilateral renal agenesis and bilateral renal dysplasia, respectively. The remaining two cases had unilateral renal agenesis with contralateral kidney showing features of cystic dysplastic kidney and renal hypoplasia, respectively. Congenital anomalies involving other organs were also found in some of the cases. The longest survival period in our series was 10 days, in accordance with the short survival period usually associated with URSM. Five of the patients were females, one was male, and the sex of one neonate could not be ascertained. One of the neonates was from a twin pregnancy; the other twin was normal.

Urorectal Septum Malformation Sequence With Retroperitoneal Neuroblastoma: A Case Report of an Unusual Association

“…9 The presence of urinary tract abnormalities, dilated bowel loops, oligohydramnios, and cystic renal mass are the common antenatal ultrasonographic findings associated with URSMS. 4,10 In our patient, non-visualization of bilateral fetal kidney and bladder and severe oligohydramnios were seen. Complete URSMS has a poor prognosis and is incompatible with life.…”

Cloacal dysgenesis sequence with bilateral renal agenesis and normal pulmonary development in twin pregnancy

“…Eighteen cases of bilateral renal agenesis associated with CDS have been reported, of which only one was a twin pregnancy 7 9. Our patient had bilateral renal agenesis in addition to a smooth perineum and absent perineal openings.…”

Urorectal septum malformation sequence—Fetal series with the description of a new “intermediate” variant. Time to refine the terminology?

“…Urorectal septum malformation (URSM) sequence is a spectrum of anomalies that encompasses different extents of cloaca division by urorectal septum (URS) in association with urogenital, anorectal, and perineum anomalies. A deficiency in caudal mesoderm and cloaca endoderm is considered as the mechanism that leads to URSM [Wheeler et al, ; Jain et al, ]. To evaluate the ultrasound manifestations and their correlation with the authentic features of URSM, we reviewed four fetal cases in our hospital over a period between 2008 and 2015.…”

“…Previously, it was postulated that the URS first invades the primitive cloaca and fuses with the cloaca membrane, which thereafter breaks down into the openings of the urogenital membrane anteriorly and the anal membrane posteriorly [Wheeler et al, ]. Incomplete partition of the persistent cloaca by URS mesoderm (by 6th weeks) and failure to break down by the cloaca membrane (by 7th weeks) result in the full form of URSM [Escobar et al, ; Jain et al, ]. In contrast to the full form of URSM, the cloaca membrane in the partial form of URSM has ruptured, while partition of the cloaca was otherwise not completed [Wheeler and Weaver, ].…”