Acrocallosal syndrome: additional manifestations

Prenatal diagnosis of a severe form of frontonasal dysplasia with severe limb anomalies, hydrocephaly, a hypoplastic corpus callosum, and a ventricular septal defect using 3D ultrasound: a case report and literature review

BACKGROUND

Frontonasal dysplasia (FND) is a rare congenital anomaly resulting from the underdevelopment of the frontonasal process, and it can be syndromic or nonsyndromic. The typical features of FND include a deformed nose and ocular hypertelorism, which are sometimes associated with cleft lip and/or palate. Only approximately 10 cases of prenatally diagnosed nonsyndromic FND have been reported in the past 30 years.

CASE PRESENTATION

A 33-year-old woman (G2P1) was referred to our center at 20 gestational weeks for bilateral hydrocephaly. We detected typical features of FND, including severe hypertelorism, median nasal bifidity, a minor cleft lip, and multiple limb anomalies using three-dimensional (3D) ultrasound. A hypoplastic corpus callosum, unilateral microtia, and a ventricular septal defect were also detected. Genetic testing, including karyotype analysis, copy number variation (CNV) analysis, trio-whole exome sequencing (trio-WES), and trio-whole-gene sequencing (trio-WGS), was performed; however, we did not find any de novo gene variants in the fetus as compared to the parents. Postmortem examination confirmed the prenatal diagnosis of FND.

CONCLUSION

The present case expands the wide phenotypic spectrum of prenatal FND patients. 3D ultrasound is a useful tool for detecting facial and limb deformities.

Intracranial cystic lesions and polydactyly associated with acrocallosal syndrome: Sonographic findings in two cases

We describe two cases of intracranial cystic lesions associated with acrocallosal syndrome. These fetal anomalies were detected on antenatal sonography and confirmed postnatally. Imaging findings include corpus callosum agenesis with interhemispheric cysts and craniofacial anomalies associated with polydactyly. Identifying the above imaging features is of importance to plan management and provide supportive care that may be required.

A de novo GLI3 mutation in a patient with acrocallosal syndrome

Acrocallosal syndrome is characterized by postaxial polydactyly, macrocephaly, agenesis of the corpus callosum, and severe developmental delay. In a few patients with this disorder, a mutation in the KIF7 gene has been reported, which was associated with impaired GLI3 processing and dysregulaton of GLI3 transcription factors. A single patient with acrocallosal syndrome and a de novo p.Ala934Pro mutation in GLI3 has been reported, whereas diverse and numerous GLI3 mutations have also been described in syndromes with overlapping clinical manifestations, including Greig cephalopolysyndactyly syndrome, Pallister-Hall syndrome, trigonocephaly with craniosynostosis and polydactyly, oral-facial-digital syndrome, and non-syndromic polydactyly. Here, we describe a second patient with acrocallosal syndrome, who has a de novo, novel c.2786T>C mutation in GLI3, which predicts p.Leu929Pro. This mutation is in the same domain as the mutation in the previously reported patient. These data confirm that mutations in GLI3 are a cause of the acrocallosal phenotype.

Acrocallosal syndrome in fetus: focus on additional brain abnormalities

Acrocallosal syndrome (ACS) is an autosomal recessive disorder characterized by craniofacial dysmorphism, agenesis or hypoplasia of the corpus callosum, duplication of the phalanges of the hallux, more rarely the thumbs, post-axial polydactyly, syndactyly and severe mental retardation. Here we report the two first descriptions of acrocallosal syndrome in fetus with extensive neuropathological study and provide new data regarding additional brain abnormalities in ACS. The first case was a 25-gestational week male fetus displaying craniofacial and limb abnormalities, with bilateral syndactyly of the fourth and fifth fingers, preaxial polydactyly of the left foot and an inter-frontal extra-bone. The second fetus was a 33-gestational week male fetus. His left hand displayed a broad thumb and 4/5 syndactyly. In both cases, gross examination of the brain showed an absence of corpus callosum associated with interhemispheric cysts. The cerebral cortex in front of the cysts was nodular. Upon microscopic examination, the nodular masses corresponded to large dysplastic areas represented by clusters of undifferentiated neurons in the white matter. The cyst wall showed arachnoidal and ependymal covering and contained numerous choroid plexus, suggesting a developmental abnormality of the ventricles. The pons and the cerebellum were hypoplastic. The dentate nuclei were fragmented. Numerous neuronal heterotopias associated with ectopic ependymal cavities were observed in the vermis in one case. The olivary nuclei were severely dysplastic too. We hope that these new data will make both the ante- and post-natal diagnosis easier, facilitate comparisons with animal models and encourage the identification of the genes responsible for this syndrome.

Schinzel acrocallosal syndrome

Acrocallosal syndrome (ACLS), also known by its synonyms: Schinzel Acrocallosal syndrome and Hallux duplication, Postaxial polydactyly and absence of corpus callosum, is a rare genetic disorder that is apparent at birth. Although autosomal recessive inheritence has been suggested, ACLS often appears to occur sporadically. Typical characteristics of ACLS are hypoplasia/agenesis of corpus callosum, moderate to severe mental retardation, characteristic craniofacial abnormalities, distinctive digital malformations and growth retardation. It has not been reported from India so far. This article reports a 5-month-old boy with combination of abnormalities consistent with acrocallosal syndrome.

Diagnosing acrocallosal syndrome

A 3-month-old male child presented with typical features of acrocallosal syndrome. He satisfies Courten's diagnostic criteria for acrocallosal syndrome.

Spectrum of the acrocallosal syndrome

Acrocallosal syndrome (ACS) is an autosomal recessive condition, characterized by agenesis of the corpus callosum, pre- and postaxial polydactyly, minor craniofacial anomalies, and, in most patients, severe psychomotor retardation. We here report on three patients with ACS demonstrating a spectrum from mild to severe involvement. Two patients had only mild to moderate mental retardation at the age of 2(1/2) and 4 years, respectively, with surprisingly good speech development. The third patient was severely affected and died at age 7 days because of persistent apnea. All three patients had agenesis of the corpus callosum, and large intracranial cysts, which in the third case was confirmed as a large arachnoid cyst at autopsy. Cranial cysts were also seen in 10/34 published cases of ACS. Thus, intracerebral cysts are a common finding in ACS and may serve in differentiating ACS from Greig cephalopolysyndactyly syndrome.

Acrocallosal syndrome in an Algerian boy born to consanguineous parents: review of the literature and further delineation of the syndrome

We present a 17-month-old boy with the acrocallosal syndrome. He was born to consanguineous parents. Abnormal findings included agenesis of the corpus callosum, a ventricular septal defect (VSD), postaxial polydactyly of fingers, cleft soft palate, intestinal malrotation, large anterior fontanelle, prominent forehead, hypertelorism, epicanthic folds, short nose and mandible and preauricular skin tags, mixed hearing loss, laryngomalacia, and growth and severe motor and mental retardation. A review of previous reports on the acrocallosal syndrome shows considerable clinical variability; minimal diagnostic criteria are proposed. A developmental field defect with disturbance of midline development is suggested.

Oculoauriculofrontonasal syndrome: report of another case and review of differential diagnosis

We report a male with features of frontonasal dysplasia, but also with ocular and auricular defects. This child most likely has oculoauriculofrontonasal syndrome, an autosomal recessive syndrome first described in 1981. We also review the literature on this syndrome, and discuss differential diagnosis.

Acrocallosal syndrome in two African brothers born to consanguineous parents

We describe two mentally retarded brothers with craniofacial anomalies, polydactyly, and other clinical manifestations compatible with the acrocallosal syndrome (ACS). These are the first black patients from Africa with this diagnosis. They are also the fourth set of sibs described with ACS, and together with the parental consanguinity documented in this family, confirm autosomal recessive inheritance of this syndrome. The clinical manifestations in our patients confirm the intrafamilial variability of the syndrome. Postnatal onset of growth retardation is proposed as an additional manifestation of ACS.

Polydactyly, campomelia, ambiguous genitalia, cystic dysplastic kidneys, and cerebral malformation in a fetus of consanguineous parents: a new multiple malformation syndrome, or a severe form of oral-facial-digital syndrome type IV?

We describe a 27-week fetus with occipitoschisis, polydactyly, campomelia, cleft palate, laryngeal dysplasia, ocular colobomata, hepatic fibrosis and intrahepatic cyst, ambiguous genitalia, cystic dysplastic kidneys, and brain malformation. This pattern of abnormalities appears unique. The differential diagnosis is discussed. The parents are first cousins, making autosomal recessive inheritance likely.

Cerebro-reno-digital syndrome in two sibs

We describe two sibs with mental retardation, facial anomalies, polydactyly, cerebellar vermis agenesis, and either meningocele or renal cystic dysplasia. The patients' condition appears to belong to a group of cerebro-reno-digital syndromes. Autosomal recessive inheritance is suggested.

Fronto-nasal dysostosis, callosal agenesis, crossed-fused ectopia, tibial hemimelia, and preaxial polydactyly of feet: severe expression of the acrocallosal syndrome?

We report on a girl with frontonasal "dysostosis," callosal agenesis, crossed-fused ectopia, tibial hemimelia, and preaxial polydactyly of feet. This pattern of the developmental defects suggests a severe form of the acrocallosal syndrome. Implications for genetic counselling are discussed.

Acrocallosal syndrome: report of a Brazilian girl

We report on a Brazilian girl born to nonconsanguineous parents and presenting with frontonasal dysostosis, callosal agenesis, abnormal upper lids, cleft lip/palate, redundant skin in the neck, grooved chin, and bifid thumbs. Major diagnostic criteria present in this patient are related to the acrocallosal syndrome. The clinical and major nosologic aspects of this condition are discussed.

A family with one child with acrocallosal syndrome, one child with anencephaly-polydactyly, and parental consanguinity

A 2-year-old boy with typical features of the acrocallosal syndrome is presented. His parents are first degree cousins and their first pregnancy resulted in spontaneous abortion whereas the offspring of their second pregnancy was an anencephalic baby with bilateral post-axial polydactyly of the hands. The possibility of including anencephaly in the spectrum of the CNS malformations of the acrocallosal syndrome is suggested.

Further delineation of the acrocallosal syndrome

The acrocallosal syndrome (ACS) was recognized by Schinzel in 1979 as a specific entity, characterized by the association of craniofacial anomalies, total or partial agenesis of corpus callosum, polysyndactyly and mental retardation. The inheritance is autosomal recessive, based on instances of recurrence in siblings and cousins and parental consanguinity. A large inbred kindred with recurrent ACS is presented. This family further strengthens the hypothesis of autosomal recessive inheritance for this syndrome. The array of clinical manifestations in this sibship and those previously reported exemplify the phenomenon of inter- and intrafamilial variability that must be considered when defining ACS. Based on a review of published reports and the present family, essential, additional and occasional findings are distinguished. Attention is drawn to geographical clustering of the families.

Acrocallosal syndrome: a new case

We describe a 2-month-old infant girl with typical clinical manifestations of the acrocallosal syndrome: characteristic face, agenesis of corpus callosum, polydactyly associated with other anomalies of the extremities, and mental retardation. The importance of a correct nosology and genetic counseling is underlined on the basis of the description of familiar cases of the syndrome.

The cerebro-reno-digital syndromes: a new community

Two "new" syndromes of multiple congenital malformations with autosomal-recessive inheritance are presented. One syndrome, found in 2 sibs of nonconsanguineous parents, included microcephaly, agencies of the corpus callosum, pterygium colli, cystic renal dysplasia (CRD) and postaxial polydactyly (PP). The other, found in 2 female sibs of consanguineous parents, included micropolygyria, CRD, PP, and polysplenia. The literature review allows the delineation of a community of 19 "cerebro-reno-digital" syndromes with autosomal recessive inheritance, 14 of which include cerebral anomalies, CRD and PP. Three more autosomal recessively inherited syndromes had CRD (or renal fibrosis) and cerebral anomalies (without digital anomalies), three others involved cerebral and digital anomalies (without renal anomalies), and one further syndrome showed CRD and ectrodactyly (without cerebral defects). Such phenotypical similarity may be attributed to the fact that there are common links in the pathogenesis of the syndromes under study.

How wide is the clinical spectrum of the acrocallosal syndrome? Report of a mild case

A boy presenting with an incomplete form of the acrocallosal syndrome is described. The syndrome shows clinical variability and it is stressed that none of the components is constant and facial dysmorphism is not always characteristic.

Acrocallosal syndrome

Acrocallosal syndrome is an autosomal recessive disorder of brain malformation and complex polydactyly. We report on an additional patient with this disorder. It is suggested that increased birth weight and cerebellar hypoplasia occur in acrocallosal syndrome. The finding of an extra bone within the anterior fontanel in our patient suggests similarity to the Xt mouse mutant, which is homologous to Greig syndrome in man. This provides additional support for the hypothesis of allelism of the Greig and acrocallosal syndromes.