Related Experiment Video
Updated: Feb 1, 2026

Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection
Published on: October 12, 2017
Cloacal Anomalies in Monoamniotic, Monochorionic Twins with Complete Urinary Tract Obstruction
Lisa B E Shields1, Dennis S Peppas2, Eran Rosenberg3
1Norton Neuroscience Institute, Norton Healthcare, Louisville, Kentucky, USA.
Insights
Persistent cloaca, a severe anorectal malformation in girls, was observed in one of monoamniotic twins. This rare case highlights challenges in diagnosing cloacal anomalies in twins.
Area of Science:
- Pediatric surgery
- Congenital anomalies
- Genetics
Background:
- Cloacal anomalies are severe anorectal malformations in females.
- They involve fused rectum, urethra, and vagina draining to a single orifice.
- Associated conditions like oligohydramnios can impact lung development.
Observation:
- This review presents a rare case of persistent cloaca in monoamniotic twins.
- The anomaly was present in only one twin, making it a discordant presentation.
- The affected twin also exhibited complete urinary tract obstruction.
Findings:
- This is the first reported case of persistent cloaca and complete urinary tract obstruction in discordant monoamniotic twins.
- The findings underscore the variability of congenital anomalies even in genetically identical twins.
- Early diagnosis and management are crucial for affected infants.
Implications:
- Highlights the importance of considering rare congenital anomalies in twin pregnancies.
- Suggests further research into the genetic and environmental factors influencing discordant anomalies.
- Emphasizes the need for specialized care for infants with complex cloacal malformations.
Abstract:
Cloacal anomalies (persistent cloaca) represent the most severe form of anorectal malformations in girls where the rectum, urethra, and vagina remain fused together inside the pelvis and drain into a single common perineal orifice. Infants with cloacal anomalies often succumb to poor lung development due to oligohydramnios. Cloacal anomaly in discordant monozygotic twins has rarely been reported in the literature. In this review, we present the first case of persistent cloaca and complete urinary tract obstruction in discordant monoamniotic twins.
Related Concept Videos
Urinary Tract Calculi I: Introduction
Urinary Tract Infection I: Introduction
Urinary Tract Infection II: Pathophysiology
Urinary Tract Calculi V: Nursing Management
Urinary Tract Calculi VI: Surgical Management
Urinary Tract Infection IV: Nursing Management

