Antenatally diagnosed cloacal exstrophy variant with intravesical phallus in a twin pregnancy

The intravesical phallus in patients with cloacal exstrophy: An embryologic conundrum

BACKGROUND

Phalluses present inside the extrophied bladder of cloacal exstrophy (CE) newborns have been sporadically reported in the literature; this clinical entity has largely unknown origins and may represent an extremely rare anomaly of CE.

OBJECTIVE

Along with nearly doubling the number of reported intravesical phalluses in the literature, this study aims to outline the common anatomic features and discuss the implications for theories of CE embryogenesis.

STUDY DESIGN

The authors retrospectively identified patients with CE and a potential intravesical phallus between 1997 and 2017 at two high-volume centers. Information was obtained about karyotype, age at closure, neurologic and renal anomalies, diastasis, phallus anatomy, and phallus biopsy pathology.

RESULTS

Six genotypic males met the inclusion criteria. Five of six had a diastasis greater than 6 cm. Four of six had paired corporal bodies in the intravesical phallus, one had a single corporal body, and one had a corporal-like structure. Five of six patients had a phallus located midline in the caudal aspect of the bladder; one was located midline in the bladder dome. Phallic biopsies were obtained in three of six patients. Two showed glanular and corporal tissue while the other showed vascular proliferation morphologically similar to that of erectile tissue.

DISCUSSION

Previous reports suggested that a superior vesicle fissure configuration, fusion of the corporal bodies, and fused bladder plates were common findings with an intravesical phallus. With the addition of new cases, the only consistent variable between patients is a phallus located anywhere along the bladder plate that can comprise a corporal-like structure, a single corporal body, or fused corporal bodies. These findings have implications for several embryologic theories. Although this is a retrospective review with a limited number of patients, the condition is exceedingly infrequent making it only observable retrospectively over decades at high volume centers.

CONCLUSIONS

The study outlined common anatomic features of the intravesical phallus in cloacal exstrophy and discussed the subsequent embryologic implications. In cloacal exstrophy newborns with presumed aphallia, meticulous inspection of the bladder plate and biopsy of any potential phallic structures can prevent resection of phallic tissue.

Genital Mobilization of Intravesical Phallus Associated With Covered Cloacal Exstrophy: A Case Report

Cloacal exstrophy is the most severe form of the exstrophy-epispadias complex, occurring in approximately 1 of every 200,000 to 400,000 live births. Variant such as covered cloacal exstrophy presentations are only one-tenth as common. Although exstrophy-epispadias complexes include genital anomalies, intravesical phallus is very rare. We report an extremely rare case of intravesical phallus with covered cloacal exstrophy that was successfully treated by phallic mobilization.

Image of the Month: Clinical Features in a Newborn with Covered Cloacal Exstrophy

Cloacal exstrophy is the most severe type of anorectal malformations that belongs to the bladder–exstrophy–epispadias complex of genitourinary malformations. Interestingly, its variant, the covered cloacal exstrophy, is often missed. The clinical findings of this variant may include an imperforate anus, low lying umbilicus, thick pubic bone, and pubic diastasis but with an intact abdominal wall. We present an interesting case of covered cloacal exstrophy with a side-by-side duplicated bladder and discuss important considerations for the time of colostomy creation in the newborn period.

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

Cloacal exstrophy variants are comprised of a wide range of characteristics, of which there are four primary features, including omphalocele, bladder exstrophy, an imperforate anus and spina bifida. The existing literature regarding the differential diagnosis from alternative urinary diseases prenatally are limited. If the bladder is present, defects in the ventral wall may not be visualized with prenatal ultrasound in certain conditions, including oligohydramnios, and differential diagnosis from urorectal septum malformation sequence is a challenge. In order to improve the diagnosis of cloacal exstrophy variants, the present study investigated the misdiagnosis of a cloacal exstrophy variant as a urorectal septum malformation in a fetus by ultrasound and analyzed the reasoning of diagnosis in detail.

Cloacal exstrophy variant with intravesical phallus: further description of anatomy and implications for gender reassignment

Variant presentations of cloacal exstrophy are exceedingly rare. Historically, genetic males with cloacal extrophy were re-assigned to the female gender due to phallic inadequacy. Early recognition of intravesical phallic structures in cloacal exstrophy cases may impact gender reassignment discussions and long-term gender outcomes. We report the case of a male infant with cloacal exstrophy presenting with an intravesical phallus, review and compare the presenting anatomical features of the three previously reported cases, and discuss the potential impact of these findings on gender reassignment in these complex children.

Classical cloacal exstrophy with intravesical phallus

Penile abnormalities such as epispadias, diphallia, asymmetry, and aphallia have been reported with cloacal exstrophy. The presence of intravesical phallus with cloacal exstrophy is presented with a review of literature.

Common ("classical") and covered cloacal exstrophy: a histopathological study and a reconstruction of the pathogenesis

Current opinion about structure and pathogenesis of cloacal exstrophy was challenged by histopathological findings and new insights into the normal development. Autopsy specimens of common (n = 3) and covered cloacal exstrophy (n = 4) with single intraexstrophic and -perineal phallic structures and perineo-exstrophic canals have been analyzed histopathologically. The findings were correlated to normal development to reconstruct the pathogenesis. By identifying a specific cloaca-derived urethra field as distinct from allantois-derived bladder fields, the exstrophic area is found to reflect the original hindgut configuration in embryos of approximately 26-29 postovulatory days gestational age (2-4 mm). Correlation to normal development suggests malfunctioning of the primitive streak/caudal eminence as a primary fault that leads to a defective cloacal region in the hindgut disturbing cloacal-intestinal-allantoic dissociation and also causes lengthening of the intestinal region into a blind-ending colon, teratoma-like lesions, and vertebral and muscular anomalies. The current idea that membranes in "covered cloacal exstrophy" represent persisting cloacal membranes is dismissed by finding an amnion-like structure, which suggests dysfunction of an umbilical ring placode as a simultaneous 2nd fault. This malfunctioning may cause omphalocele by defective demarcation of the umbilical cord and may replace midline stroma of the infraumbilical abdominal wall by extraembryonic tissue that stretches into a weak temporary membrane, may leave a perineo-extrophic canal, and may allow the formation of a single perineal or intraexstrophic phallus. Malfunctioning without replacement may result in a purely epithelial "allantoic" membrane, which by disintegrating in combination with the cloacal membrane will expose common cloacal exstrophy.

Genetische und molekularbiologische Aspekte des Blasenekstrophie-Epispadie-Komplexes (BEEK)

The bladder exstrophy and epispadias complex (BEEC) is an anterior midline defect with variable expression involving the infraumbilical abdominal wall including the pelvis, urinary tract, and external genitalia. The incidence varies with regard to ethnical background, sex, and phenotypic expression, and an incidence of 1:20,000 to 1:80,000 has been observed in the middle European population. No gene defect has been attributed to BEEC thus far and chromosomal aberrations or genetic syndromes associated with BEEC have only rarely been reported. According to epidemiological data, a complex genetic as well as a multifactorial mode of inheritance could underlie BEEC. However, no single teratogenic agent or environmental factor has been identified, which could play a dominant role in the expression of the BEEC.A risk of recurrence of 0.5-3% has been described in families with one affected subject. These values correspond to an increased recurrence risk estimated to be as high as 200- to 800-fold when compared to the common population. Due to the paucity of affected sib pairs and suitable multiplex families, conventional linkage analysis to identify candidate genes causally related with BEEC appears to be unfeasible. Large association studies and consecutive linkage disequilibrium mapping should therefore lead to the identification of candidate genes. Also new methods including matrix-based comparative genomic hybridization (CGH) are promising and have successfully been used in the past (e.g., CHARGE association). Moreover, the low incidence of the BEEC requires close cooperation between clinicians in the operative and nonoperative specialties as well as geneticists for successful gene search.

Association of cloacal anomalies, caudal duplication, and twinning

Cloacal anomalies exhibit a wide variety of morphologic types and accompanying clinical severity. The association of malformations of the cloaca with partial, complete, or conjoined twinning has been appreciated for some time, but, with the advent of prenatal ultrasound technology, appears to occur with a greater frequency than once thought. This observation has important implications for pathogenesis. We present 2 representative cases, a 19-week-old female fetus with duplication of several caudal structures and a 21-week-old male fetus with cloacal exstrophy variant and demised co-twin with lower abdominal wall defect, extruded intestinal tract, absent external genitalia, and imperforate anus. These findings and previously published theories suggest that certain models of monozygotic twinning may apply to the pathogenesis of cloacal anomalies. Specifically, the partial or complete duplication of the organizing center within a single embryonic disc may increase the risk of mesodermal insufficiency and thus account for the failure of complete development of the cloacal membrane and consequent exstrophy or other aberration.

Seven new cases of familial isolated bladder exstrophy and epispadias complex (BEEC) and review of the literature

Clustering of the bladder exstrophy and epispadias complex (BEEC) has been described in 29 families. To explore the genetic contribution we located new families through the German and Austrian Bladder Exstrophy Support Group and the Association for the Bladder Exstrophy Community (predominantly US and Canada). We report six new families with two occurrences of BEEC, one family where the proband is the product of a consanguineous union, and four discordant twin pairs. In conjunction with the published clinical and epidemiological reports this collection suggests that there is a significant genetic predisposition for susceptibility to the BEEC. It also highlights the importance of self-referral groups for recruiting families for multicenter collaborative research efforts to identify susceptibility loci.

Intravesical phallus in cloacal exstrophy

We report a case of a fused phallus located within the urinary bladder in a child with cloacal exstrophy. Surgical exploration revealed a phallus formed by fusion of the left and right corpus cavernosum and completely covered by bladder urothelium. The phallus was surgically separated from the bladder and mobilized to a more normal position and a neourethra created from tubularized bladder urothelium. Skin coverage was done using perineal skin flaps to cover the penile shaft, with the bladder urothelium covering the tip of the phallus being left intact to provide the appearance of a glans penis.