Case series: Amniotic band sequence with craniofacial abnormalities.

BACKGROUND: To objectively describe craniofacial, visual, and neurological features associated with amniotic band syndrome (ABS) and discuss likely associated multifactorial etiology. METHODS: A retrospective review of patients identified with ABS and concomitant limb involvement and craniofacial features was conducted. The following data were collected from the patients' medical records: demographic information, past medical history including birth history, surgical history, previous clinic visits/physical exams, description of craniofacial features and ABS, family history, any noted obstetric complications, visceral features, visual features, craniofacial features, intracranial features, neurological symptoms, developmental features, diagnostic tests (including radiographs, IQ testing, EEG findings, chromosomes), photographs, and treatment history. RESULTS: Seven patients were included in the final cohort, all of whom had a cleft lip with six having both cleft lip and palate. Other craniofacial abnormalities seen were facial clefts which were vertical oblique in nature, tear duct involvement, cranial deformities that required surgical correction with cranial reconstruction, recorded hypertelorism with vision and gaze abnormalities, coloboma, lagopthalmos and optic never dysplasia. CONCLUSIONS: This case series presents seven children with craniofacial involvement associated with amniotic band sequence and attempts to categorize the salient dysmorphology and neurocognitive development. Major craniofacial anomalies in patients with ABS is a rare clinical finding that cannot be completely explained on the basis of premature amniotic layer disruption alone. This study supports that the dysmorphology seen in cases of ABS with craniofacial involvement is complex and most likely multifactorial. LEVEL OF EVIDENCE: IV Case Series.

The amniotic band syndrome in the rat is associated with the activation of transforming growth factor-ß.

Amniocentesis in rats is associated with different malformations, such as cleft palate and limb deformation, resembling the human congenital amniotic band syndrome (ABS). Despite many human cases reported in the literature, little is known about the mechanisms involved in ABS. This study addressed if the activation of the transforming growth factor-ß1 (TGF-ß1) pathway is, in part, associated with amniotic band formation and growth restriction induced in rats by amniocentesis, as by a previously published model. For this purpose, quantification of TGF-ß1, α-smooth muscle actin, and collagen type I mRNA and protein levels were determined by quantitative PCR and Western blot analysis, respectively, in the fetus, its amniotic membrane, and the uterus of experimental and control rats. We found that TGF-ß1 mRNA levels are increased in the fetus and the amniotic membrane at 6 hours, whereas α-smooth muscle actin, phosphorylated Smad3, and collagen type I increased at 48 hours, suggesting that a fibrotic response is induced after the amniotic sac puncture. Furthermore, fetuses had hemorrhages, syndactyly, and amputation of limbs, similar to human ABS.

Síndrome de bridas amnióticas: caso clínico y revisión del tema / Amniotic band syndrome: case report and review of the literatura

El síndrome de bridas amnióticas (SBA) es un conjunto de anomalías congénitas, que asocia lesiones por constricción o amputación de miembros o dedos, asociado a la presencia de bridas amnióticas. Es una entidad con baja incidencia y suele ser de aparición esporádica. Suele cursar con anillos de constricción en la parte distal de los miembros o en los dedos o en casos más graves presentar amputación completa de miembros u asociación con otras malformaciones. El diagnóstico prenatal se produce sólo en el 29-50% de los casos. Presentamos el caso de una paciente con diagnóstico ecográfico de brida amniótica en la semana 12 de gestación (AU)

Amniotic band syndrome is a set of congenital birth defects consisting of constriction rings and limb or digit amputations, associated with the presence of amniotic bands. The incidence of this complication is low and its occurrence is sporadic. This syndrome usually causes constriction rings in the distal end of limbs or digits, which, in severe cases, can lead to complete amputation of the limbs or other malformations. Only 29-50% of cases are diagnosed prenatally. We report the case of a patient with an ultrasonographic diagnosis of amniotic band syndrome in week 12 of pregnancy (AU)

A stillborn fetus with amniotic band syndrome and elevated levels of alpha-fetoprotein plus beta-human chorionic gonadotropin: a case report.

Amniotic band syndrome is an uncommon, congenital fetal abnormality with multiple disfiguring and disabling manifestations. A wide spectrum of clinical deformities are encountered and range from simple ring constrictions to major craniofacial and visceral defects. We report a case of constriction amniotic bands involving upper extremities and intrauterine fetal death due to strangulation of umbilical cord. Abnormally elevated levels of alpha-fetoprotein and beta-chorionic gonadotropin were detected at 17 weeks' gestation. They were probably caused by the loss of cutaneous integrity of the fetus (alpha-fetoprotein), and by the placental attempt to counteract the fetal growth restriction and hypoxia, due to the strangulation of umbilical cord by the amniotic bands (beta-chorionic gonadotropin).

Lethal osteogenesis imperfecta with amniotic band lesions: collagen studies.

An infant was born with osteogenesis imperfecta (OI) and died after 7 days. In addition, there were amniotic constriction bands and amputations of several digits of the upper and lower limbs. The radiologic picture was suggestive of type III OI. Histomorphometric analysis of the bone showed a trabecular bone volume of 15.1% compared to 26.9% for age-matched controls. This was due to a decreased apposition of matrix by the osteoblasts. Because abnormal collagen synthesis has been suggested as the underlying defect in most forms of OI, collagen studies were undertaken using intact tissues. Bone and skin collagen solubilities were strikingly reduced. Shortened type I collagen molecules, representing 25% of the total type I collagen, were produced by pepsin digestion of the demineralized bone matrix. The molecular weight of the shortened collagen, was 10 kd lower than normal for both the alpha 1 and alpha 2 chains as determined by gel electrophoresis. The bone acetic acid-soluble collagen showed few shortened alpha-chains. Twenty-five percent of the acid-soluble bone collagen was cleaved into shortened molecules by a pepsin digestion. The shortened alpha 1 chain was purified by high-performance liquid chromatography (HPLC) and digested with CNBr. The analysis of the resulting fragments by HPLC and by gel electrophoresis unequivocally demonstrated that the shortened alpha 1 chain was derived from the alpha 1(I) chains and that the pepsin sensitivity extends from the amino terminal end of the chain to the alpha 1(I) CB5 peptide, approximately 120 residues inside the triple helix. These studies show a distinct structural abnormality of type I collagen in the bone matrix of this patient resulting in an increased sensitivity of the collagen to general enzymatic proteolysis. The importance of correlating clinical and biochemical information in OI is emphasized; classification and genetic counseling based only on clinical observations are inaccurate.