Cloacal anomaly simulating megalocystis in the first trimester

Abstract

We present a case of cloacal anomaly that simulated megalocystis in the first trimester of gestation of a female fetus. During the second trimester, repeated paracentesis was necessary to treat increasing ascites, oligohydramnios, and hydronephrosis. Our data support findings that ascites presenting with a multiloculated cystic structure on sonography during the second trimester may be typical for cloacal anomalies. Active treatment of the fetal ascites is recommended to improve the child's prospects for survival.

Sonographic evaluation of the development of the fetal rectum and anal canal

“…11 Abnormal development of the urorectal septum and anal membrane may cause high, intermediate, and low (proximal and distal, severe, and mild) types of anorectal malformations. 12 Parulekar 13 has stated that the fetal colon could not be seen before 18 weeks' gestation. Zalel et al, 10 using transabdominal US, could visualize the fetal descending colon and rectum in all 379 fetuses from 19 GA onwards.…”

First‐trimester diagnosis of imperforate anus

“…The anal membrane ruptures before the end of the 10 th week8. Abnormal development of the urorectal septum may cause high, intermediate and low types of anorectal malformations9, 10. Anorectal anomaly is more often seen in male fetuses and is associated with other malformations in over 40% of cases3.…”

Prenatal Diagnosis and Postnatal Ultrasound Findings of Cloacal Anomaly: A Case Report

“…The discovery of a megacyst during the first trimester may indicate a diagnosis of cloacal malformation [5]. The main prenatal ultrasound finding is a hypoechoic and septated retrovesical mass, located in the fetal abdomen, but the imaging is mostly inconclusive [6].…”