Pfeiffer syndrome: literature review of prenatal sonographic findings and genetic diagnosis

FGF signaling in cranial suture development and related diseases

Suture mesenchymal stem cells (SMSCs) are a heterogeneous stem cell population with the ability to self-renew and differentiate into multiple cell lineages. The cranial suture provides a niche for SMSCs to maintain suture patency, allowing for cranial bone repair and regeneration. In addition, the cranial suture functions as an intramembranous bone growth site during craniofacial bone development. Defects in suture development have been implicated in various congenital diseases, such as sutural agenesis and craniosynostosis. However, it remains largely unknown how intricate signaling pathways orchestrate suture and SMSC function in craniofacial bone development, homeostasis, repair and diseases. Studies in patients with syndromic craniosynostosis identified fibroblast growth factor (FGF) signaling as an important signaling pathway that regulates cranial vault development. A series of in vitro and in vivo studies have since revealed the critical roles of FGF signaling in SMSCs, cranial suture and cranial skeleton development, and the pathogenesis of related diseases. Here, we summarize the characteristics of cranial sutures and SMSCs, and the important functions of the FGF signaling pathway in SMSC and cranial suture development as well as diseases caused by suture dysfunction. We also discuss emerging current and future studies of signaling regulation in SMSCs.

Multidisciplinary Rehabilitation Approach to the Maxillo-Facial Complications of Crouson’s Disease: Case Report and Review

Background:

Craniofacial anomalies present a challenge to all health care practitioners since they necessitate long-term team follow-up, which is difficult to achieve outside of a major center where craniofacial anomalies teams normally collaborate.

Objectives:

The current review with an illustrative case focuses on the representation and review of Crouzon syndrome and its maxillofacial implications. Review of different varieties of gene mutations that produce craniosynostosis syndromes were discussed and focused on seven clinically distinct craniosynostosis syndromes that are precipitated by the mutation in one or more of the fibroblast growth factor receptors genes which affected the maxillofacial region.

Case presentation:

A complete clinical and radiographic case scenario of a patient suffering from Crouzon syndrome was presented, and discussion of the various disciplines and techniques used along the way to achieve the best results, as well as how team collaboration and patient compliance led to the best results were represented. The presented case was treated with orthodontic treatment, Le Fort-I osteotomy, and Le Fort-III osteotomy with extraoral distraction osteogenesis.

Conclusion:

The combination of different orthognathic surgery alternatives (Le Fort-III and Le Fort-I) with distraction osteogenesis and orthodontic treatment produced excellent outcomes with few complications, and the patient was extremely satisfied and cooperative. Early and thorough team-based care for Crouzon syndrome patients should be accessible at specialized craniofacial centers.

De Novo Heterozygous Mutation in FGFR2 Causing Type II Pfeiffer Syndrome

Pfeiffer syndrome (PS) is an autosomal dominant disorder with three subtypes stemming from heterozygous mutations in the fibroblast growth factors FGFR1 and FGFR2. The subtypes overlap with heterogeneous clinical manifestations and variable prognosis dependent on neurological and respiratory compromise that impact short- and long-term outcomes and survival. We present a male, term infant with type II PS that was diagnostically suspected antenatally based on three-dimensional ultrasonographic findings that were confirmed postnatally by craniofacial tomography and magnetic resonance imaging. A new generation sequencing panel identified a unique de novo FGFR2, c.335 A > G p. Tyr112Cys variant, the first of its kind, and features that closely aligned with subtype II PS. Initial molecular results categorized the mutation as nonpathogenic, but it was later reclassified as pathogenic. Antenatal, multidisciplinary parental counseling about the tentative diagnosis and prognosis facilitated postnatal decisions that culminated in an informed choice for palliative care and early demise.

Computer-assisted fronto-facial monobloc advancement and facial bipartition for Pfeiffer's Syndrome: the surgical technique

INTRODUCTION

In the Pfeiffer syndrome, several corrections are required to correct the facial retrusion, the maxillary deficiency or even the hypertelorism. The fronto-facial monobloc advancement (FFMA) and the facial bipartition (FB) are the gold standard surgeries. We present the correction of this deformity using a simultaneous computer-assisted FFMA and FB.

TECHNICAL NOTE

The 3D surgical planning defined the virtual correction and the bone cutting guide in view of the FFMA and the FB. Coronal and intraoral approaches were combined to perform the osteotomies. Four internal distractors were also placed for the postoperative distraction osteogenesis.

DISCUSSION

Computer-assisted surgery is helpful and a reliable option for the management of complex facio-craniosynostosis such as hypertelorism and fronto-facial retrusion.

Prenatal diagnosis of Pfeiffer syndrome type 2 with increased nuchal translucency

Pfeiffer syndrome (PS) is a rare autosomal dominant genetic disorder characterized by craniosynostosis, broad thumbs / toes. Here, we report a case of PS type 2 with increased nuchal translucency in early trimester.

Prenatal diagnosis of Pfeiffer syndrome and role of three-dimensional ultrasound: case report and review of literature

Purpose/aim of the study: We report a rare case of autosomal dominant genetic syndrome "Pfeiffer", which is part of the group of acrocephalosyndactyly, with an annual incidence <1/100,000. Three forms are known. Type I is the less common form and it is characterized by moderate-severe mediofacial hypoplasia usually with normal cognitive development. Conversely, types 2 and 3 are more common and they are associated with more severe signs and complications with a more unfavorable prognosis. The type 3 form due to the presence of a cloverleaf skull distinguishes type 2.Materials and methods: Thirty-eight-year-old primigravida was referred to our center, at 28 weeks of gestation due to borderline ventriculomegaly, macrocrania, and a short femur. First trimester screening for chromosomopathies and CF-DNA was low risk; II trimester screening ultrasound showed the presence of "short femur" and macrocrania.Result: Our ultrasound evaluation, assisted by 3D ultrasound, showed cloverleaf skull, turricephaly, moderate ventriculomegaly (13 mm), hypertelorism and exophthalmos, low ear implantation, mild rhizomelia. Ultrasound depicts Pfeiffer syndrome or other acrocephalosyndactyly syndromes (Apert syndromes, Saethre-Chotzen) or other syndromic forms of craniosynostosis like Crouzon syndrome. The NGS panel for molecular analysis of genes involved in skeletal dysplasias showed the mutation of the FGFR2 gene, de novo.Conclusions: Using three-dimensional (3D) ultrasound, it is easier to distinguish rare syndromes characterized by facial dysmorphisms such as exophthalmos, mediofacial hypoplasia, and craniosynostosis.

Prenatal Diagnosis of Pfeiffer Syndrome Patient with FGFR2 C.940-1G>C Variant: A Case Report

Background

Pfeiffer syndrome (PS) is an autosomal dominant disorder caused by mutations in fibroblast growth factor receptor FGFR1 and FGFR2 genes, occurring in approximately 1:100,000 live births. PS has a wide range of clinical expression and severity, so early prenatal diagnosis is difficult and genetic counseling is desirable. We describe a PS newborn with her ultrasound and molecular studies.

Case Report

We describe a female term newborn with cloverleaf-shaped skull, facial hypoplasia, low ears, exophthalmos and wide, broad and deviated thumbs and hallux. The patient was diagnosed by ultrasound at 29 WGA and referred to a tertiary care hospital for her follow-up. Molecular test revealed a heterozygous pathogenic variant in intron 8 of the FGFR2 gene (FGFR2: c.940-1G>C). It was a de-novo mutation. At 17 days of life, craniosynostosis correction and a Lefort-III frontomaxillary advancement were performed.

Conclusion

Pfeiffer syndrome is a devastating genetic disorder. Prenatal diagnosis according PS morphological features in prenatal ultrasound allows timely genetic counseling, early referral to third-level centers, and close follow-up in the prenatal and postnatal stages.

Craniofacial malformations and their association with brain development: the importance of a multidisciplinary approach for treatment

The craniofacial complex develops mainly in the first trimester of pregnancy, but its final shaping and the development of the teeth extend into the second and third trimesters. It is intimately connected with the development of the brain because of the crucial role the cranial neural crest cells play and the fact that many signals which control craniofacial development originate in the brain and vice versa. As a result, malformations of one organ may affect the development of the other. Similarly, there are developmental connections between the craniofacial complex and the teeth. Craniofacial anomalies are either isolated, resulting from abnormal development of the first two embryonic pharyngeal arches, or part of multiple malformation syndromes affecting many other organs. They may stem from gene mutations, chromosomal aberrations or from environmental causes induced by teratogens. The craniofacial morphologic changes are generally cosmetic, but they often interfere with important functions such as chewing, swallowing and respiration. In addition, they may cause hearing or visual impairment. In this review we discussed only a small number of craniofacial malformations and barely touched upon related anomalies of dentition. Following a brief description of the craniofacial development, we discussed oral clefts, craniofacial microsomia, teratogens that may interfere with craniofacial development resulting in different malformations, the genetically determined craniosynostoses syndromes and few other relatively common syndromes that, in addition to the craniofacial complex, also affect other organs. The understanding of these malformations is important in dentistry as dentists play an integral role in their diagnosis and multidisciplinary treatment.

Fibroblast Growth Factor Receptor 2 (FGFR2) Mutation Related Syndromic Craniosynostosis

Craniosynostosis results from the premature fusion of cranial sutures, with an incidence of 1 in 2,100-2,500 live births. The majority of cases are non-syndromic and involve single suture fusion, whereas syndromic cases often involve complex multiple suture fusion. The fibroblast growth factor receptor 2 (FGFR2) gene is perhaps the most extensively studied gene that is mutated in various craniosynostotic syndromes including Crouzon, Apert, Pfeiffer, Antley-Bixler, Beare-Stevenson cutis gyrata, Jackson-Weiss, Bent Bone Dysplasia, and Seathre-Chotzen-like syndromes. The majority of these mutations are missense mutations that result in constitutive activation of the receptor and downstream molecular pathways. Treatment involves a multidisciplinary approach with ultimate surgical fixation of the cranial deformity to prevent further sequelae. Understanding the molecular mechanisms has allowed for the investigation of different therapeutic agents that can potentially be used to prevent the disorders. Further research efforts are need to better understand screening and effective methods of early intervention and prevention. Herein, the authors provide a comprehensive update on FGFR2-related syndromic craniosynostosis.