Anogenital malformation with ambiguous genitalia as part of the OEIS complex

Prenatal diagnosis of OEIS (omphalocele, bladder exstrophy, imperforate anus, clubfeet) variant associated with increased nuchal translucency and OEIS complex with ambiguous genitalia associated with corrected transposition of the great arteries: case series and review of the literature

INTRODUCTION

The OEIS complex refers to a combination of defects consisting in omphalocele, bladder exstrophy, imperforate anus and spinal defects and represents a rare nosologic entity (from 1:200,000 to 1:400,000 pregnancies). The defect probably occurs in early blastogenesis or in mesodermal migration during the primitive streak period.

MATERIALS AND METHODS

Two cases of OEIS complex diagnosed prenatally by ultrasound are reported. The medical record regarding differential diagnosis, associated anomalies, treatment and prognosis has also been sought and reported.

CONCLUSION

Differential diagnosis with exstrophy-epispadias complex and/or cloacalexstrophy complex may be difficult antenatally by means of ultrasound. However, color Doppler has been proved to aid the diagnosis of bladder exstrophy by depicting the urine flow in direct communication with the abdominal cavity and has been useful in showing the course of the perivesical umbilical arteries. Prenatal 3D ultrasound with tomographic ultrasound imaging (TUI) and antenatal MR imaging might be useful adjuncts to conventional 2D scan in aiding the prenatal diagnosis of such malformation.

Syndromes and Disorders Associated with Omphalocele (II): OEIS Complex and Pentalogy Of Cantrell

Omphalocele-exstrophy-imperforate anus-spinal defects (OEIS) complex is characterized by a combination of omphalocele, exstrophy of the bladder, an imperforate anus, and spinal defects. Pentalogy of Cantrell is characterized by a combination of a midline supraumbilical abdominal wall defect, a defect of the lower sternum, a defect of the diaphragmatic pericardium, a deficiency of the anterior diaphragm, and congenital cardiac anomalies. This article provides a comprehensive review of OEIS complex and pentalogy of Cantrell, including the pathogenesis, prenatal diagnosis, differential diagnosis, and associated malformations. Omphalocele is an important sonographic marker for OEIS complex and pentalogy of Cantrell. Prenatal detection of an abdominal wall defect associated with multiple midline defects should alert one to the possibility of OEIS complex and pentalogy of Cantrell and prompt the genetic investigation and counseling of the disorders.

OEIS complex: prenatal ultrasound and autopsy findings

OBJECTIVE

To describe prenatal ultrasound and autopsy findings in fetuses with OEIS (omphalocele, bladder exstrophy, imperforate anus, spina bifida) complex.

METHODS

This was a retrospective study of the nine cases with OEIS complex diagnosed at our center using detailed fetal ultrasound during the last 10 years. We summarized the fetal ultrasound findings that led to the diagnosis and compared them with the autopsy results.

RESULTS

All affected fetuses were diagnosed using detailed fetal ultrasound after 16 weeks' gestation. The main prenatal findings were omphalocele, skin-covered lumbosacral neural tube defect, non-visualized bladder and limb defects. Prenatal sonography failed to detect the abnormal genitalia, bladder exstrophy and anal atresia. All cases had abnormalities in a 'diaper distribution', which helped in making the prenatal diagnosis. Eight of the nine couples chose to terminate the pregnancies following multidisciplinary counseling. The pregnancy that was continued was a case with dizygotic twins discordant for OEIS, and the affected fetus died in utero.

CONCLUSIONS

The combination of the following ultrasound findings: ventral wall defect, spinal defect and a non-visualized bladder with or without limb defects, are characteristic of OEIS complex. Diagnosis can be made with confidence as early as 16 weeks' gestation, although earlier diagnosis may be possible.

Prenatal ascertainment of OEIS complex/cloacal exstrophy—15 new cases and literature review

Omphalocele-exstrophy of the bladder-imperforate anus-spinal defects (OEIS) complex or cloacal exstrophy (EC), describes a rare grouping of more commonly occurring component malformations [Carey et al., 1978]. The etiology is unknown, but likely heterogeneous. While postnatal identification of its associated gastrointestinal, spinal, and genitourinary systems delineates the extent and natural history of OEIS complex, prenatal findings may provide additional information regarding early detection, possible causative factors, and outcome. The purposes of this study were to: (1) present the prenatal ascertainment of OEIS complex in this series of 15 cases identified through several different sources compared to the literature, and (2) discuss the relationship of these prenatal findings to possible abnormal developmental mechanisms causing OEIS complex. These 15 cases indicate that OEIS complex may be difficult to diagnose prenatally, and that the full extent of abnormalities may not be clear until postnatal exam. Confusion with limb-body wall complex (two of our cases) and pentalogy of Cantrell (one of our cases) can occur. Anal/gastrointestinal malformations and genital ambiguity are under-ascertained. Conversely, prenatal defects may resolve postnatally, yet may provide clues for pathogenetic mechanisms. For instance, the finding of nuchal thickening in our three cases (one reported) suggests vascular/hemodynamic compromise early in embryologic development, or intrathoracic compression leading to jugular lymphatic obstruction may play a role. The association of twinning and OEIS complex suggests they may occur as early as blastogenesis. Our three sets of discordant twins also suggest a non-genetic etiology for OEIS complex of uteroplacental insufficiency. This study also indicates that OEIS complex may be more common than previously thought.