Sirenomelia associated with Hypoplastic Left Heart in a Newborn

A case of sirenomelia associated with atrial septal defect: A rare case report

Introduction

and importance: Sirenomelia is a life-threatening condition caused by a rare developmental abnormality. According to the research, the incidence of sirenomelia is estimated to be between 1.5 and 4.2 per 100,000 newborns. Around 15% of cases of sirenomelia are related to a twin pregnancy, most commonly in monozygotic cases, with a 7% incidence. We're reporting on a mermaid syndrome case involving twins, one of whom was healthy and the other had sirenomelia.

Case presentation

An 18-year-old female and her first child arrived at the hospital maternity ward, and she had never been there before, and when an ultrasound was performed, it was discovered that she had two babies in her womb and on of them has clung to each other's legs, and a by elective cesarean section was performed to remove the babies, which resulted in the extraction of two boys, one of whom is healthy and the other is clinging to each other's legs.

Clinical discussion

Sirenomelia is a deadly congenital condition that affects the caudal part of the embryonic body. Although the most evident feature is the fusing of the lower limbs, Approximately 49.5 percent of pregnancies are terminated voluntarily due to fetal malformations, according to reports. The abnormality is thought to be caused by a combination of genetic predisposition and a trigger element in the environment, while the exact cause is unknown and thought to be complex. In cases of surviving sirenomelia, treatment can be administered using a multidisciplinary approach.

Conclusion

Mermaid Syndrome is a fatal congenital abnormality with a bleak outlook. Sirenomelia can be diagnosed by ultrasonography. Oligohydramnios and fused lower limbs are important symptoms that aid in diagnosis during the first trimester of pregnancy, with probable termination of the pregnancy indicated if identified early.

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Sirenomelia is a life-threatening condition caused by a rare developmental abnormality.

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Sirenoamlia with an atrial septal defect is rare.

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Interestingly, this case lived 2 weeks.

Sirenomelia: A case report

Sirenomelia also known as mermaid syndrome is a partial or complete fusion of lower extremities associated with visceral anomalies. It is a rare anomaly with a poor prognosis. Maternal age less than 20 years, maternal diabetes mellitus, and monozygotic twinning are some of the known risk factors. Diagnosis can be made via antenatal ultrasound or typical physical appearance after birth. A 2200 g baby was born from 18-year-old non-consanguineous mother via assisted breech delivery. The baby had fused lower limbs with 10 toes, absent external genitalia, and a single umbilical artery. It was small for gestational age. The baby was passed away after 30 min of birth. Young maternal age (18 years) was the identified risk factor for sirenomelia in this case. We recommend an early routine ultrasound anomaly scan in all pregnant women particularly for early detection and termination of pregnancy as the prognosis is poor. Avoiding teenager pregnancy and strict control of blood sugar in diabetic mothers can decrease this anomaly.

Dichorionic twin pregnancy with sirenomelia and chromosomal anomaly in 1 fetus: A case report

RATIONALE

Sirenomelia is a rare congenital malformation that threatens fetal survivals. The cases in which twin with sirenomelia and chromosomal abnormality have been seldomly reported. We reported a dichorionic twin case in which one twin had sirenomelia, the other twin had a normal phenotype, and they had different chromosomal abnormalities.

PATIENT CONCERNS

The abnormal twin was found at 22 weeks by ultrasound. The sirenomelia fetus was complicated with a thoracic stenosis, enlarged rectum without anal opening, the absence of bilateral kidneys, a single umbilical artery, a single lower limb, the abnormal curvature of spine, double outlet of right ventricle, which were the indicatives of the chromosome detection.

DIAGNOSIS

The copy number variation of the sirenomelia fetus was detected as a deletion of 4.8Mb in 11p11.12-11q11. The co-twin was found with del(Y)(q11.223q11.23), which was as the same as his father's. The mother had normal chromosome. The parents had normal phenotypes. It was firstly reported a microdeletion with sirenomelia fetus.

INTERVENTIONS

There was no specific treatments for the twins.

OUTCOMES

Intrauterine death of the sirenomelia fetus was found at 27 weeks and postnatal death after inevitable abortion happened to the co-twin.

LESSONS

Prenatal ultrasound was responsible for recognizing sirenomelia, and the detailed ultrasound scanning and chromosome detection should be done for the co-twin. The etiology of sirenomelia remains unclear, and genetic detection is also necessary for its pathogenesis research.

Caudal Regression Syndrome-A Review Focusing on Genetic Associations

Caudal regression syndrome (CRS) represents a spectrum of clinical phenotypes with varying degrees of malformation of the lower body with involvement of structures deriving from all 3 layers of the trilaminar embryo. We review areas of active investigation in the diagnosis, etiology, epidemiology, and treatment of the disease with a focus on underlying genetics. CRS pathobiology is complex and multifactorial with a significant contribution from environmental factors as evidenced in twin studies. Contemporary genomic and genetic investigations in both human primary tissue and murine in vitro and in vivo models implicate various genes associated with caudal differentiation and neural cell migration in embryogenesis. A large number of identified targets center around the metabolic regulation of retinoic acid and its derivatives. Dysregulation of retinoic acid homeostasis has been associated with abnormal embryonic cell migration, differentiation, and organogenesis with resulting malformations and agenesis in both a laboratory and a clinical setting. There appears to be a significant overlap in potential genetic targets with CRS and other developmental syndromes with similar presentations, such as VACTERL (vertebral defects, anal atresia, cardiac defects, tracheo-esophageal fistula, renal anomalies, and limb abnormalities) association. CRS represents a spectrum of caudal developmental abnormalities with treatment options limited to mild and moderate expressions of disease. Continued research is necessary to further clarify mechanisms of disease pathobiology and complex polygenetic and environmental interaction. Despite this, progress has been made in identifying genetic targets and downstream effectors contributing to preclinical and clinical progression.

Sirenomelia in twin pregnancy: A case report and literature review

RATIONALE

Sirenomelia is a very rare congenital malformation and characterized by fused lower extremities, oligohydramnios, renal agenesis, absent urinary tract and external genitalia, single umbilical artery, and imperforate anus. Ultrasonography is an optimal method for prenatal screening and diagnosis of sirenomelia. The incidence of sirenomelia in the twin pregnancy is extremely low.

PATIENT CONCERNS

We reported a case of 1 twin with sirenomelia in dichorionic-diamniotic twin pregnancy after in vitro fertilization and embryo transfer.

DIAGNOSES

The sirenomelia twin was diagnosed at the 2nd trimester by ultrasonic examination and complicated with oligohydramnios and a single umbilical artery, another twin was normal.

INTERVENTIONS

A regular and careful antenatal care was conducted. The parents refused to examine the chromosome of sirenomelia twin, and the chromosomal microarray analysis of the amniotic fluid sample was only achieved in the normal anatomy twin after extensively counseled by the multi-disciplinary team.

OUTCOMES

At 34+2 gestational weeks, the demise of the malformed twin occurred, while fetal heart rate monitoring of the normal twin was abnormal, and an emergency cesarean section was performed. A healthy male baby was delivered with Apgar scores of 10 and 10 at 1 and 5 minutes, respectively. The mother and the baby were followed up and are in good health until now.

CONCLUSION

Sirenomelia is a lethal condition in the perinatal period. Early antenatal diagnosis is very important. Voluntary selective termination of sirenomelia 1 in twin pregnancy may be advised. Expecting parents should be counseled by the multidisciplinary team about the management and prognosis of the sirenomelia.

A Case of Sirenomelia Associated with Hypoplastic Left Heart with a Healthy Co-Twin: A Rare Entity

Sirenomelia is a rare developmental malformation and is incompatible to life. The incidence of sirenomelia, as recorded in the literature, is estimated to be approximately between 1.5 and 4.2 per 1,00,000 births. Around 15% of sirenomelia cases are associated with twin pregnancy, most often in monozygotic cases with an incidence of 7%. In monozygotic twins, the risk of sirenomelia is nearly 100–150 times higher as compared to dizygotic twins or singleton pregnancies. Until now, only two cases of sirenomelia associated with hypoplastic left heart have been reported in the literature. Here, we present a monozygotic twin pregnancy, where one fetus was diagnosed with sirenomelia associated with hypoplastic left heart syndrome and the co-twin was absolutely healthy.