AMNIOTIC BAND SEQUENCE: A RARE CASE SEEN IN BIRAT MEDICAL COLLEGE

A 21-years-old primigravida gave birth to a Single/Live/ Term/Female baby via Lower Sec�on Caesarean Sec�on at our hospital. The mother was supervised, immunized, had uneven�ul antenatal periods, with no signiﬁcant medical history. At birth, the baby had no signs of asphyxia with a normal Appearance, Pulse, Grimace, Ac�vity and Respira�on score. Physical examina�on revealed acrosyndactyly in the right hand, le� hand at the stage of impending auto amputa�on with ring-constricon accompanied by deformity of the distal part with lymphoedema, bilateral hyperextension of the knee joints, and simple ring-constricon in lower limbs, rest were within a normal limit. Clinically diagnosed as a case of amnio�c band sequence.


INTRODUCTION
Amnio c band sequence is rare (incidence 1:1200 to 1:15000 live births) and sporadic condi on associated with t h re e ge n e ra l t y p e s o f a n o m a l i e s : d i s r u p o n s , deforma ons, and malforma ons as a complica on of 1,2 insult to the amnion. Clinical presenta on and its severity dependent upon the me of amnio c insult during intrauterine life leading to amnio c constric on band 1,2 deformi es with or without other anomalies. Asymmetric distribu on of defects is the hallmark of syndrome.

CASE REPORT
A single live, term, female weighing 3.2kg delivered by 22 years primigravida at 40 weeks of gesta on via Lower Sec on Caesarean Sec on for breech presenta on with non-progress of labor. The mother was immunized, with irregular antenatal care visits, irregular folic acid, and iron supplements, otherwise, her antenatal period was uneven ul with no history of trauma, teratogenic medica ons, diabetes, hypertension, thyroid disorders, recent infec on, and substance abuse. Prenatal ultrasound scanning done in the first and third trimesters did not reveal any abnormality. At birth, the baby had no signs of asphyxia with an Appearance, Pulse, Grimace, Ac vity and Respira on score of 7/10 and 9/10 at 1 minute and 5 minutes respec vely. Grossly umbilical cord and placenta seemed normal. Physical examina on revealed acrosyndactyly in the right hand, le hand at a stage of impending auto amputa on with ring constric on accompanied by deformity of the distal part with lymphoedema, bilateral hyperextension of the knee joints, and bilateral constric on ring band in lower limbs without neurovascular compromise. Otherwise systemic examina ons were within the normal limit. Thechild was neurologically intact with an appropriate response to s mula on and normal feeding and sleep wake cycle. Rou ne screening inves ga ons were normal. Amnio c band sequence was diagnosed clinically based on constric on ring deformi es in a random non embryonic distribu on.The baby was admi ed at neonatal intensive care unit for two days, but the pa ent's party refused further systemic inves ga ons and went on against medical advice. On follow up at next day, they said that the baby expired at the age of 3 days of life.

DISCUSSION
Embryologically, the amnio c cavity is the small cavity developed in the epiblast layer of embryoblast, which is lined by amnion developed from amnioblast derived from 3 epiblast adjacent to the cytotrophoblast. So the amnion is the innermost fetal membrane and is essen ally fetal epidermis (skin) extending con nuously out over the umbilical cord and from there it lines the chorionic cavity forming a closed sac containing the fetus, cord, and amnio c fluid. It is an integral part of the embryo which maintains the structural integrity of the gesta onal sac by its mechanical strength. Amnio c Band Sequence may be mul factorial in origin but exact e ology is an ongoing ques on since the 1930s. However several theories have been given, most known theories are: i) Intrinsic theory: defec ve germ plasm theory given by 1 streeter in 1930. 2 ii) Extrinsic theory is given by torpin in 1965. Diagnosis is usually clinical based on constric on ring deformi es in a random nonembryonic and asymmetrical distribu on of defects. Prenatal diagnosis (as early as in late first trimester) can be made by ultrasound with findings of "constric on rings with or without edema distal por on or amputated limbs'', "Thin wispy undula ng strands of amnion are seen crossing the gesta onal sac"-if not seen, we can look for restric on of movement because of its adherence (i.e change of maternal posi on may float fetus away from uterine wall revealing short band/amnio c 6,7 band). Perfusion status of distal extremity can be assessed by using color Doppler and measuring pulsa lity index. Other measures are Prenatal MRI (T weighted: amnio c 2 bands can be seen as thin wispy hypotense strands) and 6,7 Mother alpha-fetoprotein may be increased. Treatment of amnio c band syndrome requires a mul disciplinary approach. The lesions are both sta c and irreversible, and direct surgical relief is the only approach for limb constric ons. But the ming of surgical interven on and modality of interven on depends upon severity and type of presenta on. Very mild case without any func onal impairment does not require surgical interven on while acute vascular compromise, severe lymphedema, and distal nerve compression are definite indica ons for surgical interven on. Staging a surgical interven on is required like excision of constric on band at first stage surgery followed by nerve and distal so -ssue reconstruc on in second stage surgery followed by decompression fasciotomy if needed. But in some cases, one-stage surgery can be done with radical 9 excision of constric on band with so ssue reconstruc on.
With complete circumferen al constric on bands, it is recommended that a two-stage correc on approach be used. At the first opera on, one-half of the circumference is excised and the other one-half can be excised a er three to 9 six months. If diagnosed in prenatal period then fetoscopic surgery and release of constric on band (In color Doppler pulsa lity index abnormal but blood flow distal to the constricted area 6 may iden fy cases suitable for fetal surgery). Prognosis depends upon the severity of its presenta on, from good prognosis with normal life expectancy for the mildly affected infants with only minor digital or limb to death of a baby for 1 severely affected infants with craniofacial involvement.

CONCLUSION
Amnio c band sequence is the congenital condi on of unknown e ology, related most likely to the single insult i.e. amnio c band disrup on leading the unpredictable natural course. Severity depends upon the me of insult, leading to func onal complica ons to mild cosme c complica ons only. Which may need a mul disciplinary approach for a be er outcome.