Limb body wall complex: from diagnosis to prognosis (a case report)

¹Obstetrics and Gynecology Department, Faculty of Medicine, Monastir Maternity and Neonatology Centre, University of Monastir, Monastir, Tunisia

^&Corresponding author
Imen Ben Farhat, Obstetrics and Gynecology Department, Faculty of Medicine, Monastir Maternity and Neonatology Centre, University of Monastir, Monastir, Tunisia

Introduction    

The Body Wall Complex (BWC) is a rare and specific polymalformative syndrome characterized by a wide spectrum of severe body wall anomalies [1]. Traditionally, diagnosis is based on the criteria established by Van Allen et al. [2], which include the presence of two out of the following three anomalies: 1) exencephaly or encephalocele with facial clefts; 2) thoraco- and/or abdominal wall defects (schisis) and 3) limb malformations. Antenatal diagnosis can be made via ultrasound. In this report, we present a case of antenatal diagnosis of this syndrome at 18 weeks of gestation in a primiparous woman, highlighting the specific features of our observation. We also review the diagnostic criteria, etiopathogenic mechanisms and prognosis of this syndrome.

Patient and observation     

Patient information: we present the case of a 32-year-old woman with no significant medical history. She has been married for 3 years and there is no known consanguinity or family history of fetal malformations. At the time of presentation, she was 18 weeks pregnant.

Clinical findings: clinical examination revealed a uterine height consistent with the gestational age. Fetal MRI showed a viable singleton pregnancy with a normal amniotic fluid volume. Notable findings included a thoraco-abdominal coelomic defect with a narrow thorax and ectocardia in the thoracic region. The liver, stomach and intestines were observed floating in the amniotic fluid in the abdominal region. Additionally, the spine appeared short and malformed. The fetus adhered to the placenta via placento-abdominal attachments.

Timeline of current episode: the patient was referred for further imaging at 18 weeks of gestation following routine antenatal screening which indicated potential abnormalities.

Diagnostic assessment: fetal MRI was conducted, revealing significant anomalies suggestive of Limb Body Wall Complex (LBWC). The MRI findings included a thoraco-abdominal coelomic defect, ectocardia and a malformed spine. The diagnostic assessment indicated Limb Body Wall Complex (LBWC), characterized by the observed thoraco-abdominal defect, ectocardia and severe malformations.

Therapeutic interventions: after thorough discussion with the parents regarding the prognosis and options, a medical termination of pregnancy was carried out.

Follow-up and outcome of interventions: macroscopic examination at birth confirmed LBWC, with a male fetus weighing 480 grams. Observations included an asymmetrical cleft lip, a pronounced anterior coelomic defect with the heart, liver and intestines exteriorized, and a narrow thorax (Figure 1). A pathological examination for additional visceral malformations could not be performed. However, the ultrasound and macroscopic findings were deemed sufficient for diagnosis.

Patient perspective: the patient and her family were provided with comprehensive counseling and support throughout the diagnostic and decision-making process. They were informed about the nature of the condition, its prognosis and the implications of the medical termination.

Informed consent: informed consent was obtained from the patient after a detailed explanation of the diagnosis, prognosis and available options. All procedures were conducted in accordance with ethical guidelines.

Discussion     

The Limb Body Wall Complex (LBWC) is a rare polymalformative syndrome first described by Van Allen et al. in 1987 [3], characterized by three essential features: 1) exencephaly/encephalocele with facial clefts; 2) thoraco- and abdominal wall defects and 3) limb malformations. Typically, the diagnosis relies on the presence of two of these characteristics. Its incidence varies between 0.21 and 0.31 per 10,000 births [4,5]. The pathophysiology of this syndrome remains debated and poorly understood, with most studies not identifying a specific teratogen. Three main theories are discussed:

Early rupture of the amniotic sac (exogenous theory): proposed by Torpin in 1965 [6], this theory suggests that primary amniotic sac rupture leads to the formation of amniotic bands, which, through a traumatic process, cause fetal lesions.

Vascular theory (endogenous theory): proposed by Deruelle et al. [1], this hypothesis suggests that an infarction of embryonic vessels between 4 and 6 weeks of gestation causes tissue loss, disruption of embryonic development due to necrosis and anoxia, leading to deformities.

Embryonic closure defect theory: introduced by Streeter in 1930 [7] and later developed by Hartwig et al. [8], this theory attributes the syndrome to an anomaly in the development of the embryonic pedicle. This anomaly would cause rupture of the caudal and lateral folds of the embryonic disc from 32 days of gestation, leading to abdominal wall defects, persistence of the extra-embryonic coelom and anomalies of the cord, placenta and limbs. However, none of these theories fully explains all observed syndromes.

The syndrome does not show a sexual predilection and chromosomal analysis is generally unnecessary due to the absence of chromosomal abnormalities. Nevertheless, recurrence in two families has been reported, suggesting a possible genetic etiology [9]. Antenatal diagnosis by ultrasound is possible as early as the end of the first trimester, preferably via transvaginal ultrasound, with the earliest diagnosis reported at 12 weeks of gestation [1]. The most frequently observed anomalies include coelomic defects, limb anomalies, placental attachment abnormalities and spinal defects [10].

It is important to differentiate LBWC from other abdominal wall defects based on their localization: gastroschisis (located paraumbilically), omphalocele (located at the umbilical region), ectopia cordis (located on the anterior chest), cloacal dysplasia (located at the lower abdominal wall) and urachal cysts (also located in the lower anterior abdominal wall). Specific features of LBWC include the presence of membranes covering the herniated sac contents, associated intestinal anomalies, presence or absence of the bladder, scoliosis and limb malformations. The prognosis of LBWC is fatal, as the malformations are generally beyond therapeutic resources. Therefore, early diagnosis followed by medical termination of pregnancy is the preferred management option for this condition.

Conclusion     

The Limb Body Wall Complex deserves greater awareness among obstetricians and ultrasonographers, as it facilitates antenatal diagnosis and discussion of early pregnancy termination. Moreover, it helps reassure couples facing such a polymalformative syndrome, given that the recurrence risk is virtually nil.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Ben Farhat Imen and Marwa Maatoug described the case and wrote the first draft of the manuscript. Ben Farhat Imen, Marwa Maatoug, Adam Bayouth, Nedra Gharbi and Ekram Aribi did a literature search. Ekram Gerbej, Sana Alouani, and Amira Ounissi reviewed the manuscript and made a substantial contribution. Adam Bayouth, Haifa Bergaoui, Dhekra Toumi and Raja Faleh reviewed the description of the case. Haifa Bergaoui, Dhekra Toumi and Raja Faleh did a concurrent literature search. All the authors have read and agreed to the final version of the manuscript.

Figure     

Figure 1: newborn with Limb Body Wall Complex with polymalformative syndrome weight

References