Challenges in the Prenatal Diagnosis of Cloaca

Background:

Cloaca is a common excretory channel for the genital, urinary, and gastrointestinal tracts. It is considered a severe anorectal malformation caused by failed partitioning of the genital, rectal, and urinary tracts.

Methods:

We report 5 infants with cloaca at birth who were identified prenatally by one or more of the following on prenatal ultrasound (US): ambiguous genitalia, a cystic pelvic/abdominal mass, hydronephrosis, ascites, a single umbilical artery, and oligohydramnios.

Results:

A cystic pelvic/abdominal mass and ambiguous genitalia were each observed in 3 cases by prenatal US. Ambiguous genitalia was observed in all 5 neonates at birth. There were 2 twin pregnancies (dichorionic/diamniotic and monochorionic/monoamniotic), with only 1 twin in a set affected with cloaca.

Conclusion:

Pediatricians should be alert to the prenatal US findings that may raise suspicion of a persistent cloaca to improve both prenatal counseling and family preparation.

Management of antenatally detected kidney malformations

Congenital anomalies of the kidneys and the urinary tract (CAKUT) are one of the most common sonographically identified antenatal malformations. Dilatation of the renal pelvis accounts for the majority of cases, but this is usually mild rather than an indicator of obstructive uropathy. Other conditions such as small through large hyperechogenic and/or cystic kidneys present a significant diagnostic dilemma on routine scanning. Accurate diagnosis and prediction of prognosis is often not possible without a positive family history, although maintenance of adequate amniotic fluid is usually a good sign. Both pre- and postnatal genetic screening is possible for multiple known CAKUT genes but less than a fifth of non-syndromic sporadic cases have detectable monogenic mutations with current technology. In utero management options are limited, with little evidence of benefit from shunting of obstructed systems or installation of artificial amniotic fluid. Often outcome hinges on associated cardiac, neurological or other abnormalities, particularly in syndromic cases. Hence, management centres on a careful assessment of all anomalies and planning for postnatal care. Early delivery is rarely indicated since this exposes the baby to the risks of prematurity in addition to their underlying CAKUT. Parents value discussions with a multidisciplinary team including fetal medicine and paediatric nephrology or urology, with neonatologists to plan perinatal care and clinical geneticists for future risks of CAKUT.

Renal dysplasia characterized by prominent cartilaginous metaplasia lesions in VACTERL association: A case report

BACKGROUND

Renal dysplasia is the most important cause of end-stage renal disease in children. The histopathological characteristic of dysplasia is primitive tubules with fibromuscular disorganization. Renal dysplasia often includes metaplastic cartilage. Metaplastic cartilage in renal dysplasia has been explained as occurring secondary to vesicoureteral reflux (VUR). Additionally, renal dysplasia is observed in renal dysplasia-associated syndromes, which are combinations of multiple developmental malformations and include VACTERL association.

CASE PRESENTATION

We observed the following multiple developmental malformations in a 108-day-old male infant during a nephrectomy: a nonfunctioning right kidney with VUR, hemidiaphragmatic eventration, a ventricular septal defect (VSD) with tetralogy of Fallot in the heart, cryptorchidism, and hyperdactylia. These developmental anomalies satisfied the diagnostic criteria for VACTERL association. A surgical specimen of the right nonfunctioning kidney revealed prominent cartilaginous metaplasia in the renal dysplasia with VUR. The densities of the ectopic cartilaginous lesions in this nonfunctioning kidney were extraordinarily high compared with other renal dysplasia cases. Giemsa banding of his genome produced normal results. The patient has not undergone further detailed genomic investigation.

CONCLUSION

This case might be a novel type of VACTERL association, that is, renal dysplasia combined with prominent cartilaginous metaplasia, tetralogy of Fallot and VSD of the heart, hemidiaphragmatic eventration, and hyperdactylia.

Renal dysplasia

Renal dysplasia is an aberrant developmental disease usually diagnosed during the perinatal and childhood years. Prevalence is estimated at 0.1% of infants (via ultrasound screening) and 4% of fetuses and infants (via autopsy study). Occurrences may be combined with abnormalities in the collecting system or associated with complex syndromes. Histopathology shows primitive tubules surrounded by a fibromuscular collar. The differential diagnosis includes renal dysplasia, hypoplasia, and renal atrophy. Immunohistochemical expression of the paired box genes 2 and 8 (PAX2/8) and Wilms tumor 1 (WT1) is increased in the primitive ducts and fibromuscular collar, respectively. Renal dysplasia pathogenesis is not well understood, but may be caused by a nephron-inductive deficit due to ampullary inactivity or abnormal budding of the ureteric bud from the mesonephric duct. Either the PAX2 mutation only or cross-talk with the p53 pathway is involved in this deficit. Nephrectomy is the treatment of choice for symptomatic renal dysplasia.

Epidemiology of partial urorectal septum malformation sequence (or 'persistent cloaca'): a population-based study in seven regions of England and Wales, 1985-2010

BACKGROUND

Partial urorectal septum malformation (pURSM) sequence (or 'persistent cloaca') is a rare congenital anomaly characterised by a joining of the urethral, anal, and genital openings into a single common channel. This study describes the epidemiology of pURSM sequence in England and Wales including prevalence, additional anomalies, and pregnancy outcomes.

METHODS

All cases of pURSM sequence prospectively notified to seven congenital anomaly registers in England and Wales during 1985-2010, whether delivered as live births, spontaneous fetal deaths (≥20 weeks' gestation), or elective terminations of pregnancy for fetal anomaly (TOPFA, any gestation), formed this population-based cohort. The risks of spontaneous fetal and infant death were examined by Kaplan-Meier analysis. Differences in prevalence over time, and between regions, were examined by multilevel Poisson regression.

RESULTS

117 cases were recorded among 4,251,241 total births. Six (5%) pregnancies resulted in spontaneous fetal deaths, 53 (45%) in TOPFA, and 58 (50%) in live births. The prevalence was 2.8 (95% CI 2.3 to 3.4) per 100,000 total births, increasing significantly over time (p=0.002) and differing significantly between regions (p=0.005). 77 cases (66%) had at least one additional major congenital anomaly outside the perineum, including 67 (57%) renal, 29 (25%) musculoskeletal, 26 (23%) digestive system, and 24 (21%) cardiovascular anomalies. The risks of spontaneous fetal and infant death were estimated as 8.9% (95% CI 4.1 to 18.8) and 26.3% (95% CI 15.1 to 43.4) respectively.

CONCLUSIONS

This is the largest study of the epidemiology of pURSM sequence. The information will be valuable for families and health professionals whenever a case of pURSM sequence is diagnosed.

Cloacal malformation variants in male

OBJECTIVE

The published surgical literatures have referred only to females as having cloacal defects and the incidence in males is not well established. As during embryogenesis, both sexes have to pass through the stage of a cloaca, there is every chance of development of cloacal anomalies in males also. Here, we are presenting our experience of male cloacal malformations.

METHODS

We identified four cases of male cloaca by reviewing medical records of all anorectal malformation (ARM) patients treated at our institution in the past 19 years. Time of presentation, clinical, radiological, cystoscopic and operative findings, and outcomes were analysed.

RESULTS

Out of 1,837 patients, we identified four cases (0.2 %) of male cloacal variants. All presented after 45 days (range 46 days to 28 years). Three of them had proximal hypospadias, two had a vaginal remnant and cystoscopic evaluation showed the length of the common channel ranged from 0.5 to 8 cm. One patient died of multiple anomalies and the other patients are doing well following reconstruction.

CONCLUSION

None of the male cloacal patients presented in the neonatal period, proximal hypospadias was the common external genital abnormality and half of them had a vagina. Surgical outcome was satisfactory. The scarcity of reported cases of this group is a subject of further research.

Presentación de un caso con múltiples malformaciones congénitas: asociación VACTERL

La asociación VACTERL es un conjunto de malformaciones congénitas que ocurre en varias combinaciones, entre las cuales encontramos: malformaciones Vertebrales, atresia Anal, anomalías Cardiovasculares, fistula Traqueo esofágica, atresia Esofágica, malformaciones Renales y displasia de las extremidades (Limb), fundamentalmente en el hueso radial. Para su diagnóstico se requiere la presencia de, al menos, tres de los siete criterios enumerados y se realiza por medio de ecografía a partir de la semana 18 de gestación. Aun no se ha reconocido etiología específica para esta patología; se cree que es producto de una influencia teratogénica entre la cuarta y octava semana de gestación. El pronóstico de estos pacientes es muy pobre, ya que fallece el 50-85% de los niños en el primer año de vida, sobreviviendo después del primer año de vida solo un 12-15%. 

Cell death serves as a single etiological cause of a wide spectrum of congenital urinary tract defects

PURPOSE

We genetically disrupted the wolffian duct in mice to study the affected organogenesis processes and to test the hypothesis that cell loss can be the developmental basis for a wide spectrum of congenital anomalies in the kidney and urinary tract.

MATERIALS AND METHODS

We used Hoxb7-Cre transgenic lines (HC1 and HC2) to induce diphtheria toxin production from a ROSA(DTA) allele, disrupting the wolffian duct and derivatives.

RESULTS

The first set of mutants (HC1;ROSA(DTA/+)) exhibited agenesis of the kidney, ureter and reproductive tracts. The second set of mutants (HC2;ROSA(DTA/+)) exhibited diverse defects, including renal agenesis/hypoplasia, hydronephrosis, hydroureter, ureter-vas deferens fistulas in males and ureter-oviduct/uterus fistulas in females. The phenotypic differences correspond to the degree of apoptosis induced caudal truncation of the wolffian duct, which is less severe and more variable in HC2;ROSA(DTA/+) mice. Whenever the wolffian duct failed to reach the urogenital sinus, the ureter failed to separate from the wolffian duct, suggesting that ureteral migration along the common nephric duct to the cloaca and the subsequent common nephric duct degeneration constitute the only pathway for separating the ureter and wolffian duct derivatives.

CONCLUSIONS

The diverse and severe defects observed emphasize the central role of the wolffian duct in providing progenitors and signals for urogenital development. These results also indicate that the quantitative difference in cell death induced caudal truncation of the wolffian duct can lead to a wide range of qualitatively distinct defects, and that cell death can serve as a single etiological cause of a wide spectrum of congenital kidney and urinary tract defects.

Prenatal diagnosis of cloacal malformations

INTRODUCTION

Prenatal diagnosis of anorectal malformations currently occurs in 0-15.9% of screened cases. In cloacas, these numbers are unknown. We speculate that some images from prenatal ultrasound studies may suggest the diagnosis of cloaca, but are not recognized because of a lack of suspicion for this diagnosis.

METHODS

A retrospective review of the medical records of 489 patients born with cloaca was performed; 95 of them had prenatal ultrasound reports that represent the material analyzed for this study. A literature review was performed, finding 31 publications, with 68 cloaca patients detected by prenatal images. The abnormal findings of our patients were compared with those described in the literature to determine the most common abnormal prenatal images found in patients with cloaca.

RESULTS

The 95 ultrasound reports found in our patients described 270 abnormalities, the most frequent were: abdominal/pelvic cystic/mass (39), hydronephrosis (36), oligohydramnios (23), distended bowel/bowel obstruction (19), ascites (15), 2 vessel cord (14), dilated bladder (14), dilated ureter (14), polyhydramnios (10), echogenic bowel (8), multicystic kidney (8), "ambiguous genitalia" (7), hydrops fetalis (7), hydrocolpos (4), absent kidney (3), abnormal spine (3), and anorectal atresia (3). In spite of these findings, the radiologists who interpreted the studies only suspected a cloaca in 6 cases (6%). The literature review showed 212 abnormalities in 68 demonstrated cloaca patients. The most frequent were: abdominal/pelvic cystic/mass (46), hydronephrosis (44), ascites (21), oligohydramnios (20), distended bowel (11), multicystic dysplastic kidney (7), ambiguous genitalia (6), non-visualization of the bladder (6), two-vessel cord (5), dilated bladder (5), intraabdominal calcification (4), polyhydramnios (4), enterolithiasis (4), hydrometrocolpos (3), and dilated ureter (3).

CONCLUSION

We conclude that it is possible to suspect the diagnosis of cloaca, prenatally, more frequently than what currently occurs, looking at the same images but with an increased index of suspicion for cystic abdominal masses and a combination of gastrointestinal and urological abnormalities.