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Amniotic band syndrome is a rare congenital deformity associated with wide range of structural abnormalities commonly involves limbs. Amniotic bands also called constriction bands, congenital ring, streeter dysplesia. Sequence bands and annular defects are anomalous bands that encircle either partially or completely a digit or an extremity [1].

The clinical presentation ranges from simple soft tissue constrictive bands to amputation of digities or more severely the whole limb due to dysplastic vasculature. The prevalence of Aminiotic band syndrome is 7.7/10,000 live birth and as high as 178/10,000 among abotions [2,3]. In Nigeria there is a report 0.16-3% prevalence of Amniotic band syndrome [4,5]. In Ethiopia there are no reported cases of Amniotic band syndrome to date. We therefore report a case seen with the aim of highlighting its existence in this region.

A 30 years old Gravida 4 Para 3 (all alive and healthy) came for ANC follow up at a gestational age of 28⁺⁴ weeks. She had regular ANC follow up at Mearg General Hospital, in Northern Ethiopia. She had no history of drug intake and no history of chronic medical illness. Her laboratory investigations like VDRL were normal. Ultrasound finding were a severely malformed fetus. The detailed sonographic findings were, the fetus had anencephaly, grossly excessive amniotic fluid, gestational age by femoral length was 22 weeks.

After discussion with mother and written informed consent obtained pregnancy were terminated with misoprostol per the hospital protocol. The fetal was found to have absent cranial vault, cleft palate, absent orbits, absent auricles, no abdominal wall defect, well-formed extremities, well-formed vertebral bones and 3 vessel umbilical cord. These defects are so divers that the pathogenesis of this condition cannot be explained by a single mechanism (Figure 1).

Figure 1: Amniotic band syndrome.

Amniotic band syndrome comprises of a spectrum of anomalies which vary in severity. The triad ABS includes amnion-denuded placenta; fetal attachment or entanglement by amniotic remnants; fetal deformation, malformation and/or disruption [6,7]. The malformations in the case described illustrate the wide range of defects seen in ABS. ABS etiopathogenesis is still unknown, but there are main theories [8-11]. Widely accepted "extrinsic model”, proposed by Torpin and Faulkner in 1996 explains defect genesis by rupture of aminion in early pregnancy. With forming of amniotic band and amniotic liquids loss, following by extrusion of all or parts of the fetus in to the chorionic cavity. Band entrap the parts of the engrowing fetus, therefore fetus limbs and other body parts are subjected to compressions, which compromises fetal circulation and then fetal growth and development by consecutive disturbances of fetal physiology and anatomy. The intrinsic model was proposed by Steeter in 1930 and suggests that the anomalies and the fibrous bands have a common origin, caused by a perturbation of developing germinal disc of early embryo. Beside ABS etiopathogenesis, risk factors which start such sequence of events are also poorly known. Most cases of ABS are not of origin, and there is no recurrence in sibling or children of affected adults. However, there are some reports of ABS families with collagen disorders, more specifically Elhler-Danlos syndrome [12].

Some other possible etiology factors besides inheritance were explored in several studies none of which our patient had [13-17].

Beside all previously mentioned malformations caused by amniotic bands itself, a subset of cases manifest additional finding that are not consistent with that mechanism [18]. In the case presented polyhydramnios is not explained.

Amniotic band syndrome can be diagnosed by sonographic examinations in the prenatal period, which can sometimes amniotic bands, but more often malformations consistent with ABS, as well as oligohydraminus and reduction of fetal movements. Physical examination is the main stay of postnatal diagnosis of ABS [19,20].

Surgery is the main stay therapy in most cases ABS, with an individual approach to every single cases. Interdisciplinary consulting and work is very often needed (Plastic surgeon, Orthopedic surgeon, Orthodontist, Ophthalmologist and Neurologist) [21].

Like in this case when fetal anomalies incompatible with life are prenatally seen, pregnancy termination is advised [12].

Fetal congenital deformities brings with the multiple challenges to the treating obstetrician/clinicians, that of detecting the congenital anomalies in the fetus, predicting the prognosis about them and informing the parents, terminating the pregnancy in appropriate situations. Prenatal sonographic examination helps us in diagnosing these anomalies in early pregnancy. Physical examination is the main stay postnatal diagnosis of Amniotic band syndrome.