Apert syndrome: what prenatal radiographic findings should prompt its consideration?

Apert syndrome: A case report of prenatal ultrasound, postmortem cranial CT, and molecular genetic analysis

Apert syndrome is characterized by craniosynostosis, mid-facial hypoplasia, and symmetric syndactyly. Prenatal diagnosis is challenging until the skull and facial anomalies become more pronounced during the third trimester. We present a case in which typical sonographic signs of Apert syndrome were observed after 23 weeks of gestation. Following termination of the pregnancy, both clinical features such as craniofacial abnormalities and syndactyly and cranial 3D-CT images showed high correlation with the previous sonographic findings. Furthermore, genetic analysis revealed a spontaneous mutation, c.755C≥G (p.S252W), in the FGFR2 gene, with this mutation implicated in the etiology of Apert syndrome.

Apert Syndrome With FGFR2 758 C > G Mutation: A Chinese Case Report

Background: Apert syndrome is considered as one of the most common craniosynostosis syndromes with a prevalence of 1 in 65,000 individuals, and has a close relationship with point mutations in FGFR2 gene.

Case report: Here, we described a Apert syndrome case, who was referred to genetic consultation in our hospital with the symptom of craniosynostosis and syndactyly of the hands and feet. Craniosynostosis, midfacial retrusion, steep wide forehead, larger head circumference, marked depression of the nasal bridge, short and wide nose and proptosis could be found obviously, apart from these, ears were mildly low compared with normal children and there was no cleft lip and palate. Mutation was identified by sanger sequencing and a mutation in the exon 7 of FGFR2 gene was detected: p.Pro253Arg (P253R) 758 C > G, which was not found in his parents.

Conclusion: The baby had Apert syndrome caused by 758 C > G mutation in the exon 7 of FGFR2 gene, considering no this mutation in his parents, it was spontaneous.

Prenatal Imaging of Craniosynostosis Syndromes

This article reviews the prenatal diagnosis of those syndromes in which craniosynostosis is a key feature. Although not an exhaustive list, the authors highlight conditions that may be encountered with some regularity, especially in a higher volume fetal imaging center. Rare conditions are also discussed. Normal sutural anatomy and development are first reviewed, followed by a discussion of specific syndromes, the salient imaging findings, and pathologic as well as postnatal correlations when possible.

Comparison of ultrasound and magnetic resonance imaging in the prenatal diagnosis of Apert syndrome: report of a case

BACKGROUND

The birth prevalence of Apert syndrome is estimated at 1:64,500 and accounts for about 4.5 % of all craniosynostosis with a male/female ratio equal to 1:1. It is associated to allelic mutations in the fibroblast growth factor receptor 2 (FGFR2) gene. Majority cases are sporadic. Prenatal ultrasound diagnosis is based on the detection of abnormal cranial shape, midfacial hypoplasia and bilateral syndactyly of hands and feet, hypertelorism, and exorbitism. Other abnormalities includes central nervous system anomalies, congenital heart diseases, cleft palate, and urogenital diseases.

CASE REPORT

A 37-year-old Caucasian woman, gravida 2, para 1, was referred to our center of Prenatal Diagnosis for routine ultrasound at 21 weeks of gestation. We detected irregular head shape, dolicocephaly, prominent forehead, bilateral mild ventriculomegaly, suspicion of partial agenesis of the corpus callosum, hypertelorism, and midfacial hypoplasia, with a depressed nasal bridge and syndactyly, prompting a suspicion for Apert syndrome. Magnetic resonance excluded agenesis of corpus callosum and confirmed bilateral mild ventriculomegaly. A follow-up ultrasound, performed at 23 weeks, confirmed the anomalies showed in the previous scan. An amniocentesis was performed. The results showed a normal male karyotype, while the molecular genetic test confirmed a mutation in FGFR2 gene. Fetus macroscopic analysis showed compatible features.

CONCLUSIONS

Our case underlines the complementary role of ultrasound and magnetic resonance imaging in the early prenatal diagnosis of Apert syndrome.

Rapid detection of de novo P253R mutation in FGFR2 using uncultured amniocytes in a pregnancy affected by polyhydramnios, Blake's pouch cyst, and Apert syndrome

OBJECTIVE

To present prenatal ultrasound and molecular genetic diagnosis of Apert syndrome.

CASE REPORT

A 30-year-old, gravida 3, para 2 woman was referred for genetic counseling at 32 weeks of gestation because of polyhydramnios and craniofacial and digital abnormalities in the fetus. She had undergone amniocentesis at 18 weeks of gestation because of maternal anxiety. Results of amniocentesis revealed a karyotype of 46,XX. A prenatal ultrasound at 32 weeks of gestation revealed a female fetus with a fetal biometry equivalent to 32 weeks, polyhydramnios with an increased amniotic fluid index of 26.1 cm, frontal bossing, midface hypoplasia, hypertelorism, Blake's pouch cyst with an apparent posterior fossa cyst in communication with the fourth ventricle on axial images, digital fusion, and bilateral syndactyly of the hands and feet. A DNA testing for the FGFR2 gene was immediately performed using uncultured amniocytes obtained by repeated amniocentesis, which revealed a heterozygous c.758C>G, CCT>CGT transversion leading to a p.Pro253Arg (P253R) mutation in the FGFR2 gene. Subsequently, a diagnosis of Apert syndrome was made. Molecular analysis of the FGFR2 gene in the parents did not reveal such a mutation. The fetus postnatally manifested frontal bossing, midface hypoplasia, and bilateral syndactyly of the hands (mitten hands) and feet.

CONCLUSION

Prenatal diagnosis of polyhydramnios, frontal bossing, and midface hypoplasia associated with brain and digital abnormalities should include a differential diagnosis of Apert syndrome. A molecular analysis of FGFR2 using uncultured amniocytes is useful for rapid confirmation of Apert syndrome at prenatal diagnosis.

Cellular signaling by fibroblast growth factors (FGFs) and their receptors (FGFRs) in male reproduction

The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system.