Apert syndrome: craniofacial challenges and clinical implications.

Apert syndrome is a rare acro-cephalo-syndactyly syndrome characterised by craniosynostosis, severe syndactyly of hands and feet, and dysmorphic facial features. It demonstrates autosomal dominant inheritance assigned to mutations in the fibroblast growth factor receptor gene, as a result of which signals are not received to produce necessary fibrous material necessary for normal cranial sutures. Deformities are generally cosmetic but can affect various functions such as hearing, visual abnormalities, swallowing, writing, etc, so a multidisciplinary approach is needed for their management.Presently described is a case of a male in his late adolescence who was medically diagnosed with Apert syndrome at birth. Physical appearance and dental examination of the patient included acrocephaly, prominent forehead, ocular hypertelorism, proptosis, short and broad nose, pseudo-prognathism, dental crowding and ectopia, maxillary hypoplasia, low hairline, webbed neck, pectus excavatum and severe bilateral syndactyly of hands and feet.

Perinatal imaging findings of a fetus with Pfeiffer syndrome and a heterozygous c.1019A>G, p.Tyr340Cys (Y340C) mutation in FGFR2 presenting a cloverleaf skull, craniosynostosis and short limbs on prenatal ultrasound mimicking thanatophoric dysplasia type II.

OBJECTIVE: We present perinatal imaging findings of a fetus with Pfeiffer syndrome and a heterozygous c.1019A>G, p.Tyr340Cys (Y340C) mutation in FGFR2 presenting a cloverleaf skull, craniosynostosis and short limbs on prenatal ultrasound mimicking thanatophoric dysplasia type II (TD2). CASE REPORT: A 37-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 46,XY. However, craniofacial anomaly was found on prenatal ultrasound at 21 weeks of gestation, which showed a cloverleaf skull with severe craniosynostosis and relatively short straight long bones. Fetal magnetic resonance imaging (MRI) analysis at 22 weeks of gestation showed a cloverleaf skull, proptosis and relatively shallowing of the sylvian fissures. Prenatal ultrasound at 24 weeks of gestation showed a fetus with a cloverleaf skull with a biparietal diameter (BPD) of 6.16 cm (equivalent to 24 weeks), an abdominal circumference (AC) of 18.89 cm (equivalent to 24 weeks) and a femur length (FL) of 3.65 cm (equivalent to 21 weeks). A tentative diagnosis of TD2 was made. The pregnancy was subsequently terminated, and a 928-g malformed fetus was delivered with severe craniosynostosis, proptosis, midface retrusion, a cloverleaf skull, broad thumbs and broad big toes. The broad thumbs were medially deviated. Whole body X-ray showed a cloverleaf skull and straight long bones. However, molecular analysis of FGFR3 on the fetus revealed no mutation in the target regions. Subsequent whole exome sequencing (WES) on the DNA extracted from umbilical cord revealed a heterozygous c.1019A>G, p.Tyr340Cys (Y340C) mutation in the FGFR2 gene. CONCLUSION: Fetuses with a Y340C mutation in FGFR2 may present a cloverleaf skull on prenatal ultrasound, and WES is useful for a rapid differential diagnosis of Pfeiffer syndrome from TD2 under such a circumstance.

The phenotype of MEGF8-related Carpenter syndrome (CRPT2) is refined through the identification of eight new patients.

Carpenter syndrome (CRPTS) is a rare autosomal recessive condition caused by biallelic variants in genes that encode negative regulators of hedgehog signalling (RAB23 [CRPT1] or, more rarely, MEGF8 [CRPT2]), and is characterised by craniosynostosis, polysyndactyly, and other congenital abnormalities. We describe a further six families comprising eight individuals with MEGF8-associated CRPT2, increasing the total number of reported cases to fifteen, and refine the phenotype of CRPT2 compared to CRPT1. The core features of craniosynostosis, polysyndactyly and (in males) cryptorchidism are almost universal in both CRPT1 and CRPT2. However, laterality defects are present in nearly half of those with MEGF8-associated CRPT2, but are rare in RAB23-associated CRPT1. Craniosynostosis in CRPT2 commonly involves a single midline suture in comparison to the multi-suture craniosynostosis characteristic of CRPT1. No patient to date has carried two MEGF8 gene alterations that are both predicted to lead to complete loss-of-function, suggesting that a variable degree of residual MEGF8 activity may be essential for viability and potentially contributing to variable phenotypic severity. These data refine the phenotypic spectrum of CRPT2 in comparison to CRPT1 and more than double the number of likely pathogenic MEGF8 variants in this rare disorder.

Ser252Trp mutation in fibroblast growth factor receptor 2 promotes branching morphogenesis in mouse salivary glands.

OBJECTIVES: The purpose of this study was to perform morphological and immunohistochemical (IHC) analysis of the submandibular glands (SMGs) in early development in Apert syndrome model mice (Ap mice). METHODS: ACTB-Cre homozygous mice were mated with fibroblast growth factor receptor 2 (Fgfr2+/Neo-S252W) mice; ACTB-Cre heterozygous mice (ACTB-Cre mice) at embryonic day (E) 13.5 served as the control group, and Fgfr2+/S252W mice (Ap mice) served as the experimental group. Hematoxylin and eosin (H&E) staining was performed on SMGs; Total SMG area and epithelial area were determined, and the epithelial occupancy ratio was calculated. Immunostaining was performed to assess the localization of FGF signaling-related proteins. Next, bromodeoxyuridine (BrdU)-positive cells were evaluated to assess cell proliferation. Finally, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed to assess apoptosis in SMGs. RESULTS: The epithelial occupancy ratio was significantly higher in SMGs of Ap mice compared with that in SMGs of controls. FGF7 and bone morphogenetic protein 4 (BMP4) exhibited different localizations in SMGs of Ap mice compared with SMGs of controls. Cell proliferation was higher in SMGs of Ap mice compared with that of controls; however, apoptosis did not different significantly between the two groups. CONCLUSION: Our results suggest that enhanced FGF signaling conferred by missense mutations in FGFR2 promotes branching morphogenesis in SMGs of Ap mice.

Clinical and genetic findings of two cases with Apert syndrome / Hallazgos clínicos y genéticos de dos casos con síndrome de Apert

Abstract Background: Craniosynostosis is described as the premature fusion of cranial sutures that belongs to a group of alterations which produce an abnormal phenotype. Case report: Two unrelated female patients with clinical findings of Apert syndrome-characterized by acrocephaly, prominent frontal region, flat occiput, ocular proptosis, hypertelorism, down-slanted palpebral fissures, midfacial hypoplasia, high-arched or cleft palate, short neck, cardiac anomalies and symmetrical syndactyly of the hands and feet-are present. In both patients, a heterozygous missense mutation (c.755C>G, p.Ser252Trp) in the FGFR2 gene was identified. Conclusions: Two cases of Apert syndrome are described. It is important to recognize this uncommon entity through clinical findings, highlight interdisciplinary medical evaluation, and provide timely genetic counseling for the family.

Resumen Introducción: Las craneosinostosis se describen como la fusión prematura de las suturas craneales y resultan un grupo de alteraciones que producen un fenotipo anormal. Caso clínico: En este informe de casos se presentan dos pacientes de sexo femenino no emparentadas con hallazgos clínicos del síndrome de Apert, caracterizado por acrocefalia, región frontal prominente, occipucio plano, proptosis ocular, hipertelorismo, fisuras palpebrales hacia abajo, hipoplasia mediofacial, paladar alto o hendido, cuello corto, cardiopatía congénita y sindactilia simétrica en manos y pies. En ambas pacientes se identificó una mutación cambio de sentido en heterocigosis (c.755C>G, p.Ser252Trp) en el gen FGFR2. Conclusiones: Se presentan dos casos de síndrome de Apert. Es importante reconocer a través de los hallazgos clínicos esta entidad infrecuente, resaltar la evaluación médica interdisciplinaria y proporcionar un oportuno asesoramiento genético a la familia.

Molecular analysis of exons 8, 9 and 10 of the fibroblast growth factor receptor 2 (FGFR2) gene in two families with index cases of Apert Syndrome / Análisis molecular de los exones 8, 9 y 10 del gen del factor de crecimiento de fibroblastos (FGFR2) en dos familias con casos índice de síndrome de Apert

Introduction: Apert syndrome (AS) is a craniosynostosis condition caused by mutations in the Fibroblast Growth Factor Receptor 2 (FGFR2) gene. Clinical features include cutaneous and osseous symmetric syndactily in hands and feet, with variable presentations in bones, brain, skin and other internal organs. Methods: Members of two families with an index case of Apert Syndrome were assessed to describe relevant clinical features and molecular analysis (sequencing and amplification) of exons 8, 9 and 10 of FGFR2 gen. Results: Family 1 consists of the mother, the index case and half -brother who has a cleft lip and palate. In this family we found a single FGFR2 mutation, S252W, in the sequence of exon 8. Although mutations were not found in the study of the patient affected with cleft lip and palate, it is known that these diseases share signaling pathways, allowing suspected alterations in shared genes. In the patient of family 2, we found a sequence variant T78.501A located near the splicing site, which could interfere in this process, and consequently with the protein function.

Introducción: El síndrome Apert (SA) es un síndrome que cursa con craneosinostosis el cual es ocasionado por mutaciones en el gen del Receptor 2 del Factor de Crecimiento de Fibroblastos (FGFR2). Se caracteriza clínicamente por presentar sindactilias cutáneas y óseas en manos y pies de forma simétrica, cursa además con manifestaciones variables esqueléticas, cerebrales, en piel y otros órganos internos. Métodos: Miembros de dos familias con caso índice de Síndrome Apert fueron evaluados con el objetivo de describir las características clínicas relevantes y el análisis molecular (secuenciación y amplificación) de los exones 8, 9 y 10 del gen FGFR2. Resultados: La familia 1 está constituida por la madre, el caso índice y un medio hermano que presenta labio y paladar hendido. En esta familia solo se encontró la mutación S252W en la secuencia del exón 8 del gen FGFR2 del caso índice. A pesar no encontrarse mutaciones dentro del estudio realizado al paciente afectado con labio y paladar hendido, se conoce que estas patologías comparten vías de señalización, lo que permite sospechar alteraciones en genes compartidos. En la familia 2, el resultado molecular del caso índice reportó la variante T78.501A en la secuencia del intrón 8, la cual se sitúa cercana al sitio de splicing, pudiendo alterar este proceso con una consecuente alteración de la función de la proteína.

Síndrome de Crouzon: a propósito de 2 casos. Entidades craneoestenóticas alélicas de los genes FGFR / Presentation of two cases of Crouzon syndrome: allelic cranio-stenotic conditions of FGFR genes

Introducción: La craneosinostosis consiste en una fusión patológica precoz de una o varias suturas craneales. El 20% de los casos corresponde a formas sindrómicas con patrones hereditarios mendelianos, mientras que el 80% restante a formas no sindrómicas, pero con transmisión hereditaria en el 10-14% de los casos. A propósito de 2 pacientes con síndrome de Crouzon, se revisan los aspectos clínicos y genéticos. Pacientes y métodos: Paciente 1: niña de 35 días con macrocefalia progresiva, abombamiento de la fontanela, proptosis ocular, hipertelorismo y estrabismo divergente. Rx de cráneo con sinostosis de la sutura sagital. Fue intervenida quirúrgicamente a los 3 y 8 meses por desarrollo de pansinostosis. Paciente 2: niño de 3 años 8 meses con cefaleas de tipo migrañoso de un año de evolución. Presentaba acantosis nigricans. Rx de cráneo y TC craneal con impresiones digitales y fondo de ojo con discreto borramiento papilar. Tras 18 meses apareció edema de papila y en la TC craneal se detectó pansinostosis, requiriendo intervención quirúrgica. Resultados: Hemos presentado un paciente con síndrome de Crouzon clásico (paciente 1) y otro con acantosis nigricans (paciente 2), diagnosticándose por su particular fenotipo clínico. Conclusiones: Dada la amplia diversidad de formas alélicas en los genes FGFR que cursan con craneosinostosis, conociéndose hasta 10 entidades, realizamos una revisión de las mismas. En las formas sindrómicas, como nuestros 2 casos, conviene detallar al máximo los signos clínicos pues pueden orientar el diagnóstico, y el estudio molecular permitirá en ocasiones confirmarlo y ofrecer asesoramiento genético a las familias(AU)

Introduction: Craniosynostosis is an abnormal and premature fusion of any cranial suture. Twenty per cent of them involve any specific syndrome with Mendelian transmission; the other 80% are "non syndromic", although but 10-14% of them are genetically transmitted. Using the experience of two patients with Crouzon syndrome, a clinical and genetic review is performed. Patients and methods: Patient 1: girl of 35 days of age with progressive macrocephaly, protrusion of fontanel, ocular proptosis, hypertelorism and divergent strabismus. Cranial RX with sagittal synostosis. Surgical operation was performed with 3 months and 8 months of age due to development of pansynostosis. Patient 2: boy of 3 years 8 months of age with headaches of migrainous type of one year onset. He had acanthosis nigricans. Cranial RX and cerebral CT with evident digital markings and fundus of eye with undefined papillary limits, but 18 month later oedematous papilla were evident and pansynostosis was detected, so surgery was performed. Results: We present a patient with classical Crouzon syndrome (patient 1) and another with acanthosis nigricans (patient 2), both diagnosed by the description of characteristic clinical features. Conclusions: Ten craniosynostotic clinical forms are currently known as allelic variations of the FGFR genes, and as such have reviewed them. As in our two cases, in syndromic types is very important the accurate study of the phenotype to orientate the diagnosis, although the molecular study will confirm it in many patients and genetic counselling offered(AU)

Síndrome de Saethre-Chotzen: suas alterações dismórficas. Relato de caso / Saethre-Chotzen syndrome: facial dysmorphic features. A case report

Introdução: A síndrome de Saethre-Chotzen é um distúrbio raro de herança autossômica dominante causada por mutações no gene TWIST, localizado no lócus 7p21; os pacientes apresentam defeitos na cabeça (plagiocefalia e assimetría facial) e na parte distal das extremidades, dedos encurtados e ligados pela persistência de uma membrana entre eles (sindactilia). Objetivo: Apresentar um relato de caso da síndrome de Saethre-Chotzen, discutindo as características diagnósticas que diferenciam essa síndrome dos outros tipos de craniossinostoses e o diagnóstico diferencial. Descrição: Estudante de 11 anos apresentando os seguintes sinais clínicos: plagiocefalia decorrente de craniossinostose, acrobraquicefalia, assimetria facial e hemimelia, com ausência da porção distal do antebraço direito. Comentários: Apresentamos um caso ilustrativo da síndrome de Saethre-Chotzen, que constitui a mais frequente das doenças com craniossinostoses e descrevemos as importantes alterações faciais dismórficas da síndrome.

Síndrome de Pfeiffer familiar / Familial Pfeiffer syndrome

Presentamos una casuística familiar de síndrome de Pfeiffer, con 15 miembros afectados a lo largo de cuatro generaciones. Los 5 casos pediátricos fueron atendidos y diagnosticados en el Hospital Clínico Universitario de Valladolid entre los años 2002 y 2008, con un seguimiento clínico y radiológico. Se revisa el diagnóstico diferencial con el resto de las craneosinostosis autosómicas dominantes (síndromes de Apert, Crouzon...) y se muestra la heterogeneidad en su expresión clínica de los diferentes probandos en la serie familiar. En cuanto a la genética molecular, estos síndromes familiares comparten mutaciones en el receptor tipo 2 del factor de crecimiento de los fibroblastos (FGFR), si bien el síndrome de Pfeiffer también presenta alteraciones en el FGFR tipo 1.Hoy día es posible también realizar el diagnóstico prenatal mediante ultrasonidos y obtener un mejor pronóstico en las formas familiares con un tratamiento neuroquirúrgico precoz (AU)

We report a family case series of Pfeiffer’s Syndrome, with 15 affected members along 4 generations. 5 pediatric cases were attended and diagnosed in the University Clinical Hospital of Valladolid between 2002-2008, with clinical and radiological follow up. Each case underwent differential diagnosis with the rest of the autosomal dominant craniosynostosis (Apert, Crouzon…)and displayed heterogeneity on its clinical expression. Genetically, the affected members of a family syndrome share mutations in the fibroblast growth factor receptor (FGFR)type 2, while Pfeiffer Syndrome also presents alterations in the type 1 FGFR. Today it is possible in the familial cases, to do prenatal diagnosis by ultrasound and offer an early neurosurgery treatment and a better prognosis (AU)

Síndrome de Apert. Reporte de un caso / Apert syndrome. A case report

El síndrome de apert es una afección genética poco frecuente que se transmite con una herencia autosómica dominante relacionado con la edad paterna avanzada, la mayoría de los casos son esporádicos y no existe una incidencia racial, El síndrome se caracteriza por cráneosinostosis congénita, sindactilia de las manos y de los pies, anquílosis diversas y sinostosis progresiva de las manos, de los pies y de la columna vertebral. Por la rareza de esta afección nos vimos motivado a describir las características clínicas de un caso de síndrome de Apert en un paciente de 30 años que ingresó en el servicio de medicina del Hospital General Docente de Morón. (AU)

Síndrome de Apert: manifestaciones cutáneas, presentación de un caso / Cutaneus manifestations: Aperts syndrome, report of a case

El síndrome de Apert o acrocefalosindactilia tipo I, es un trastorno congénito de herencia autosómica dominante, aunque se han descripto casos de mutación espontánea. Se caracteriza por malformaciones craneofaciales, y sindactilia de manos y pies. En menor proporción hay alteraciones cutáneas, cardiovasculares, genitourinarias, gastrointestinales y respiratorias. Comunicamos el caso de un paciente de 34 años con manifestaciones clínicas de este síndrome y resaltamos el compromiso cutáneo. Revisamos la bibliografía existente al respecto (AU)

Síndrome de Apert (acrocefalosindactilia): presentación de un caso con estudio citogénico y dermatoglífico / Apert's syndrome (acrocephalo-sindactyly): presentation of a case with citogenetic and dermathogliphic study

Presentamos un caso de acrocefalosindactilia o síndrome de Apert en una niña de raza negra de 18 meses de edad. La sindactilia era total en las 4 extremidades y las alteraciones craneofaciales típicas. El estudio citogenético mostró que es cromatinopositiva y tiene un complemento cromosómico normal, 46, XX. Los dermatoglifos de la niña, de manos y pies son anormales y semejan a los descritos en otras variedades de sindactilias. Se hizo también un estudio dermatoglífico en ambos progenitores de origen haitiano(AU)