Prenatal Diagnosis of Cloacal Dysgenesis Sequence: Differential Diagnosis from Other Forms of Fetal Obstructive Uropathy

Abstract

Cloacal dysgenesis sequence (CDS) is a rare cause of fetal obstructive uropathy (FOU). The prenatal differentiation of CDS from other FOU is important because CDS is not amenable to in utero surgical intervention in the form of vesicoamniotic shunts. We evaluated the prenatal characteristics of 8 fetuses with CDS, including a pair of monozygotic twins concordant for CDS, in order to identify features that would enable differentiation from other forms of FOU. Pathologic examination in each of the 8 fetuses confirmed characteristic features of absent anal, genital, and urinary orifices associated with a smooth perineum and abnormal phallic development. Associated abnormalities included dysplastic kidneys in 6, hydroureters in 5, intraluminal colonic calcifications in 2, and hypoplastic lungs in 5. Five of these fetuses initially presented as posterior urethral valve syndrome. Six fetuses had megacystis, and 4 underwent vesicocenteses to evaluate urinary electrolytes, all of which were in the ‘poor-risk’ category. Six fetuses were male and 2 female, contradicting earlier claims that CDS occurs only in females. Evaluation of candidates for in utero surgical intervention should include fetal karyotype, and CDS should be suspected in cases of FOU in whom the karyotype reveals a male fetus and sonographic evaluation demonstrates colonic calcifications or abnormal phallic development. Diagnostic microendoscopy may be of benefit in such cases.

Perinatal Outcomes of Fetal Abdominal Cysts and Comparison of Prenatal and Postnatal Diagnoses

“…The mean gestational age of liveborn cases was 37.4 weeks ( 8 2.27) and the mean birth weight was 2,907.2 g ( 8 554.71). Surgery was (1) ileal atresia (1) intestinal obstruction (4) ileal atresia (2) intestinal atresia (1) urogenital sinus abnormality (1) jejunal atresia (2) jejunal atresia (2) Mesenteric (2) mesenteric (2) mesenteric (1) normal (1) Ovarian (14) ovarian cyst (14) ovarian cyst (8) mesenteric cyst (2) normal (4) Genitourinary (21) double collecting system (1) double collecting system (1) megacystis-PUV (13) megacystis-PUV (8) renal cystic dysplasia (1) urogenital sinus abnormality (2) normal (2) pelviectasis (1) pelviectasis (1) renal cyst (5) megaureter (1) ( table 1 ), 36 had uniloculated, 13 biloculated, 2 solid, and 20 multiloculated complex appearance. Among the uniloculated simple cystic lesions, the most common localization was in the right (17) and upper (11) quadrants.…”

Prenatal diagnosis of cloacal anomalies

“…The cloaca is a transient structure during embryonic development which forms from the developing tail-fold at 3 weeks by the con¯uence of the allantois and hindgut [11±13]. The partitioning of the cloaca by the craniocaudal growth of urorectal septum and lateral indentations close to the cloacal membrane begins at 4 weeks and is complete by < 5 weeks [11]. By the sixth week the cloaca is divided, resulting in a urogenital sinus anteriorly and a separate hindgut posteriorly.…”

Perinatal Findings in a Male Fetus with Congenital Megacystis and Anorectal Malformations

“…These male fetuses had abnormal phallic development in addition to obstructive uropathy, oligohydramnios, and anorectal malformations. Cloacal dysgenesis sequence is not amenable in utero and is incompatible with survival [13]. Our case is a rare occurrence of congenital megacystis in the setting of imperforate anus with rectourinary fistula.…”

“…However, in the present study a dilated colon and intraluminal calcification were not found prenatally. Recently, a cloacal dysgenesis sequence has been identified in male fetuses [13]. These male fetuses had abnormal phallic development in addition to obstructive uropathy, oligohydramnios, and anorectal malformations.…”