Misdiagnosis of a cloacal exstrophy variant as urorectal septum malformation in a fetus by ultrasound: A case report

A fetus of partial urorectal septum malformation sequence characterized by complete septate uterus: A case report

RATIONALE

Urorectal septum malformation sequence (URSMS) is an extremely uncommon anomaly characterized by imperforate anus accompanied by multiple genitourinary malformations. Here, we report a case of URSMS identified by the autopsy and classified into partial URSMS. Prenatal diagnosis is challenging for clinicians due to the difficulty of early identification of URSMS and the relative lack of specific features in ultrasound. We intend to share our experiences.

PATIENT CONCERNS

One fetus was indicated abdominal cystic structure, abdominal effusion and right renal pelvis separation (7 mm) by ultrasound at 28 + 1 week's gestation. After the pregnancy was terminated, the fetal tissues were performed to be tested by autopsy, copy number variation sequencing and whole exon sequencing.

DIAGNOSES

Based on the clinical characteristics, ultrasound, autopsy, and genetic test findings, the fetus was diagnosed with URSMS.

INTERVENTIONS

After genetic counseling, the couple opted to terminate her pregnancy.

OUTCOMES

The copy number variation results of the fetus showed a 0.48-MB duplication fragment of uncertain significance on chromosome 8p23.3, while the whole-exome sequencing revealed a SAL-LIKE 1 gene mutation. The autopsy of the fetus showed imperforate anusa, the abdominal cyst was further confirmed with complete septate uterus and the lower urethra and vagina converge formed a lumen.

LESSONS

Individuals with URSMS during the fetal period might be misdiagnosed due to atypical features of URSMS. Once structural abnormalities especially cystic mass of the futuses in the lower abdomen, URSMS should be considered.

Clues and pitfalls in prenatal diagnosis of classic cloacal exstrophy using ultrasonography and magnetic resonance imaging: A case with sequential observation from 17 to 30 weeks' gestation and literature review

We observed a case of classic cloacal exstrophy (CE) from 17 to 30 weeks' gestation. At 17 weeks, an omphalocele and single umbilical artery (SUA) were diagnosed with a normal female karyotype on amniocentesis. A pelvic cystic adjacent to SUA, considered to be the bladder at 17 weeks, became swollen to form double cysts at 25 weeks. A phallus-like structure along the lower abdomen was additionally detected, leading to the diagnosis of CE. Fetal magnetic resonance imaging (MRI) at 30 weeks confirmed that the phallus-like structure was of intestinal origin. The presence of a non-visualizable bladder together with abdominal wall defect or omphalocele and an elephant trunk-like deformity are key findings in the prenatal diagnosis of classic CE. Fetal MRI was useful in confirming ultrasonographic findings and obtaining additional findings for the diagnosis of CE. We have discussed clues and potential pitfalls in diagnosing CE, with a review of the literature.