Neurofibromatosis tipo 1: seudoaneurisma de arteria temporal / Neurofibromatosis type 1: temporal artery pseudoaneurysm

Neurofibromatosis is a disease caused by a mutation on chromosome 17, and was described by Friedrich Daniel von Recklinghausen in 1882. It is characterized by the appearance of benign tumors in different organs that can occasionally turn malignant. Four types of neurofibromatosis are described; being type 1 the most frequent, produced by mutations in NF1 gene inhibiting neurofibromin, and in a small percentage of cases by 17q11 microdeletion. In 50% of cases, it is autosomal dominant and the penetrance is 100%. Its prevalence is 1/3000 births and affects both sexes equally. The diagnosis is done by the presence of characteristic signs and can be corroborated through genetic studies. It usually manifests in childhood and involves skin issues, formation of multiple neurofibromas, gliomas of the optic pathway, hamartomas of the iris, bone malformations, arterial hypertension, vascular alterations, intracranial and peripheral nerve sheath tumors, seizures, hydrocephalus, cognitive deficits and learning difficulties. Vascular disease is a rare complication that is usually asymptomatic and can affect the vessels that go from the proximal aorta to small arterioles, including arterial stenosis, aneurysms and arteriovenous malformations. The prognosis is usually good, with neoplasms and vascular diseases being the cause of early mortality. We present the case of a patient with a diagnosis of neurofibromatosis type 1 who presents a rupture of a pseudoaneurysm dependent on the left temporal artery with a fistula with drainage to the superficial facial vein that resulved favorably by endovascular treatment.

La neurofibromatosis es una enfermedad producida por una mutación en el cromosoma 17; fue descrita por Friedrich Daniel von Recklinghausen en 1882. Se caracteriza por la aparición de tumores benignos en distintos órganos que, ocasionalmente, pueden malignizarse. Se describen cuatro tipos de neurofibromatosis; la más frecuente es la de tipo 1, que se produce por mutaciones en el gen NF1, inhibiendo la neurofibromina, y en un pequeño porcentaje de casos por microdeleción 17q11. En el 50% de los casos es autosómica dominante y la penetrancia es del 100%. Su prevalencia es de 1/3000 nacidos vivos y afecta por igual a ambos sexos. El diagnóstico se efectúa por la presencia de signos característicos y puede corroborarse por medio de estudios genéticos. Suele manifestarse en la infancia y comprometer la piel, con formación de múltiples neurofibromas, gliomas de la vía óptica, hamartomas del iris, malformaciones óseas, hipertensión arterial, alteraciones vasculares, tumores intracraneales y de las vainas de nervios periféricos, convulsiones, hidrocefalia, déficit cognitivo y dificultades del aprendizaje. La enfermedad vascular es una complicación rara que suele ser asintomática, puede afectar los vasos que van desde la aorta proximal hasta las arteriolas pequeñas, incluyendo estenosis arteriales, aneurismas y malformaciones arteriovenosas. El pronóstico suele ser bueno; las causas de mortalidad temprana son las neoplasias y las vasculopatías. Presentamos el caso de un paciente con diagnóstico de neurofibromatosis tipo 1 que presentó ruptura de seudoaneurisma dependiente de la arteria temporal izquierda, con fístula con drenaje a la vena facial superficial, que se resolvió favorablemente mediante tratamiento endovascular

Identification of a novel NF1 mutation in a Chinese family affected with neurofibromatosis type I / 中华医学遗传学杂志

OBJECTIVE@#To explore the molecular basis for a Chinese family affected with neurofibromatosis type I.@*METHODS@#Peripheral blood samples were collected from the proband and his parents. Potential mutations of NF1 gene were screened by PCR and Sanger sequencing. Pathogenicity of candidate mutations was analyzed using Polyphen-2 and Provean software.@*RESULTS@#Two mutations of the NF1 gene, including c.702G>A (synonymous mutation) and c.1733T>G (missense mutation), were discovered in the proband. Neither mutation was found in his parents and 50 healthy controls. Bioinformatics analysis indicated that the c.1733T>G mutation (p.Leu578Arg) was probably damaging. The affected codon L578 is highly conserved across various species.@*CONCLUSION@#The c.1733T>C mutation of the NF1 gene probably underlies the neurofibromatosis type I in this family.

A Novel c.6766_6767insAA Mutation in the Neurofibromin Gene in a Patient with Neurofibromatosis Type 1-Associated Glioblastoma / 대한소아신경학회지

Neurofibromatosis type 1 (NF-1) is an autosomal dominant neurocutaneous syndrome caused by mutations in the neurofibromin gene. NF-1 patients have a high risk of tumors, and optic glioma is the most commonly observed central nervous system tumor in these patients. However, glioblastoma is extremely rare in pediatric NF-1 patients. Here we report the discovery of a novel heterozygous c.6766_6767insAA (p.Ser2256Lysfs*4), pathogenic mutation in the neurofibromin gene in a 17-year-old boy with NF-1-associated glioblastoma.

A Case Report of Precocious Puberty in Children Associated with Hypothalamic Hamartoma in Neurofibromatosis Type 1 / 대한소아신경학회지

Neurofibromatosis type 1 (NF1) is a common neurocutaneous syndrome that presents with multiple café-au-lait spots, skinfold freckling, dermatofibromas, neurofibromas, and Lisch nodules. Mutations of the NF1 gene, encoding the protein neurofibromin, have been identified as the cause of this disease. NF1 can also present with precocious puberty and be associated with optic pathway tumors. Hypothalamic hamartoma as the cause of precocious puberty in patients with NF1 has been rarely described in the literature. Here, we report the findings for a patient with NF1 and precocious puberty associated with a hypothalamic hamartoma who had a newly discovered 14-bp deletion mutation in exon 5 of NF1. To our knowledge, this is the first time this combination is reported in the literature.

[ neurofibromatosis type 1 family report with multiple cases in 3 consecutive Generations]

Neurofibromatosis type1 [NF1] with the incidence of 1 in 3500 births, is the most common disorder which affects skin and peripheral nervous system. NF1 results from mutations in NF1 gene. The NF1 gene spans 350kbp and to date, nearly 2434 mutations in it were reported. The gene with 100 percent penetrance is located on chromosome 17 encoding neurofibromin protein. Recently, many challenges of its genetic analysis have been overcome through the application of new sequencing techniques. In present study patients with neurofibromatosis type 1 have been characterized from clinical symptoms such as presence of cafe au lait spot, plexiform neurofibroma, optic nerves involvement, presence of several patients in first degree relatives. These patients were in different ages including 73, 63, 44, 20 with different symptoms and severities of disease. In this communication, a NF1 family with 4 cases in 3 generations has been presented

Molecular analysis of two pediatric cases with sporadic neurofibromatosis type 1 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To report on two children manifesting multiple cafe-au-lait spots suspected as neurofibromatosis type 1, and perform NF1 gene mutation analysis.</p><p><b>METHODS</b>Blood samples were collected from the 2 children, their unaffected parents and 100 normal controls. The entire coding region of the NF1 gene was amplified by PCR and subjected to direct sequencing.</p><p><b>RESULTS</b>In patient 1, a novel frameshift mutation c.1948delT (p.Leu650TyrfsX38) was identified in exon 12 of the NF1 gene. And in patient 2, a previously reported nonsense mutation c.541C>T (p.Gln181X) was revealed in exon 4b. The same mutations were not detected in their unaffected parents or 100 normal controls.</p><p><b>CONCLUSION</b>The two patients were diagnosed with neurofibromatosis type 1 by molecular genetic testing. The pathogenic mutations were c.1948delT and c.541C>T, respectively.</p>

Neurofibromatosis tipo 1 (NF1) y su diagnóstico molecular como estrategia del diagnóstico diferencial y a edades tempranas / Molecular diagnosis as a strategy for differential diagnosis and at early ages of neurofibromatosis type 1 (NF1)

Neurofibromatosis type 1 (NF1), is a haploinsufficient and multisystemic disease, caused by inherited or sporadic mutations in the NF1 gene. Its incidence is one in 2,500 to 3,000 individuals, it has an autosomal dominant pattern of inheritance, high clinical variability, complete penetrance and age-dependent complications. Neurofibromin is the product of the NF1 gene and is believed to act as a tumor suppressor since the loss of its function has been associated with benign and malignant tumors in neural crest-derived tissues. Only two correlations between clinical phenotype and mutant alleles in the NF1 gene have been observed. The established criteria for disease diagnosis are very efficient in adults and children older than 3 years of age, but not for children under this age. Mutational analysis is therefore recommended to confirm the disease in young children with a negative family history. A pathogenic mutation in the NF1 should be added to the list of diagnostic criteria. Mutational analysis is also recommended for differential diagnosis and for prenatal or pre-implantation genetic diagnosis, taking into consideration the family history and the type of method to be applied. Molecular studies of this disease using different complimentary molecular techniques and bioinformatics tools have characterized NF1 gene mutations at both the DNA and mRNA levels, increasing the mutational spectrum. Consequently, about 1,289 defects have been reported to date, mainly nonsense/missense mutations, deletions and splice site defects.

Neurofibromatosis Type I Associated with Malaria: A Case Report and Review of Literature.

Neurofibromatosis (von Recklinghausen disease) is a genetic disorder which is now not been considered to be most common due to a gradual increase in its number of cases worldwide. Its prevalence found is around 1 in 4000-5000 individuals with the incidence been found equally in all regions and reported in almost all ethnic groups. Two-three million cases are reported all over world so far with this disorder. It is an autosomal dominant trait with varied age range of the cases reported from 6 years to late adulthood. Disease occurs by a genetic mutation in the neurofibromatosis Type 1 (NF1) gene (tumor suppressor gene) which is located on chromosome no. 17 at 17q11.2, responsible for coding of neurofibromin, a cytoplasmic protein. The effect of this mutation is elicited in almost all systems of the body with mild to severe complications. About half of the cases reported are present with new mutations in the NF1 genes. A patient afflicted with NF1 has around 50-60% of chances of transmitting the disease to each of his/her offspring. Presenting here a case of the female patient diagnosed malaria associated with NF1.

Early-Onset Breast Cancer in a Family with Neurofibromatosis Type 1 Associated with a Germline Mutation in BRCA1 / 한국유방암학회지

Neurofibromatosis type 1 (NF1), which may occur as an autosom-al dominant disorder, is caused by the absence of neurofibromin protein due to somatic mutations in the NF1 gene, and it has been associated with an increased risk of breast cancer. Herein we describe a family with two women affected by both NF1 and early-onset breast cancer. We evaluated whether the concomitance of NF1 and early-onset breast cancer could be due to disease-causing mutations in both NF1 and BRCA1 gene in a Korean family with clinical features of both NF1 and hereditary breast cancer. Mutation analyses identified nonsense mutations in NF1 and BRCA1 genes. Our findings indicate that an awareness of the possible concomitance of NF1 and BRCA1 gene mutations is important for identifying the genetic origin of early-onset breast cancer in patients with NF1 to achieve early detection of cancers and decrease breast cancer-associated morbidity and mortality in these patients.

A novel indel NF1 mutation identified in a patient with neurofibromatosis type 1 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the genetic etiology in a Chinese patient with neurofibromatosis type 1 (NF-1).</p><p><b>METHODS</b>All coding exons and the flanking sequences of neurofibromin 1 (NF1) gene from the patient were captured, individually barcoded and subjected to HiSeq2000 high-throughput sequencing. Suspected mutation was validated in the nuclear family members with Sanger sequencing.</p><p><b>RESULTS</b>A novel indel mutation, c.789_790delAGinsT, was identified in the exon 8 of the NF1 gene in the patient but not in her asymptomatic parents. The mutation was predicted to have caused shifting of the reading frame and a premature downstream stop codon (p.K263Nfs*18). Two known polymorphisms, c.888+108 C>T (rs2953000) and c.888+118 G>T (rs2952999), was detected in the flanking of the indel mutation in the patient and her father. Sequencing chromatogram for the family indicates that above changes are located on the same chromosome.</p><p><b>CONCLUSION</b>The c.789_790delAGinsT, as a de novo mutation occurring on the paternally derived chromosome, is most likely to be causative for the disease. Compared with Sanger sequencing, targeted next-generation sequencing is more efficient and can dramatically reduce the cost for the genetic testing of NF-1.</p>

A Case of Vitiligo Coexistent with Neurofibromatosis Type 1 / 대한피부과학회지

No abstract available.

Spinal Cord Ependymoma Associated with Neurofibromatosis 1 : Case Report and Review of the Literature

Patients with neurofibromatosis 1 (NF1) are predisposed to develop central nervous system tumors, due to the loss of neurofibromin, an inactivator of proto-oncogene Ras. However, to our knowledge, only three cases of ependymomas with NF1 have been reported in the literature. The authors present a case of NF1 patient with a spinal cord ependymoma. She was referred for about half a year history of increasing numbness that progressed from her fingers to her entire body above the bellybutton. Magnetic resonance imaging revealed a relative-demarcated, heterogeneously enhanced mass lesion accompanied by perifocal edema in C5-7 level, a left-sided T11 spinous process heterogeneously enhanced mass in soft tissue, intervertebral disk hernia in L2-5 level, and widespread punctum enhancing lesion in her scalp and in T11-L5 level. The patient underwent C5-7 laminectomies and total excision of the tumor under operative microscope, and intraoperative ultrasonography and physiological monitoring were used during the surgery. Histopathologically, her tumor was found to be a ependymoma without malignant features (grade II in the World Health Organization classification). Therefore, no adjuvant therapy was applied. Following the operation, the patient showed an uneventful clinical recovery with no evidence of tumor recurrence after one year of follow-up.

Pulmonary Hypertension in Neurofibromatosis Type 1: A Case Report / 대한내과학회지

Neurofibromatosis type I is a genetic disease caused by mutations in the neurofibromin 1 (NF1) gene. Although it is characterized by a number of distinct clinical features, including cafe au lait macules, freckling in the axillary or inguinal regions, neurofibromas, and Lisch nodules (iris harmartomas), it can affect all physiological systems in the body [1]. Neurofibromatosis-related pulmonary hypertension has also been reported, and some patients showed a poor prognosis despite having received proper medical treatment [2-4]. We herein describe a case of pulmonary hypertension in a patient with neurofibromatosis type I who had no identified risk factors of pulmonary hypertension. To our knowledge, this is the first such report in Korea.

Pulmonary Hypertension in Neurofibromatosis Type 1: A Case Report / 대한내과학회지

Neurofibromatosis type I is a genetic disease caused by mutations in the neurofibromin 1 (NF1) gene. Although it is characterized by a number of distinct clinical features, including cafe au lait macules, freckling in the axillary or inguinal regions, neurofibromas, and Lisch nodules (iris harmartomas), it can affect all physiological systems in the body [1]. Neurofibromatosis-related pulmonary hypertension has also been reported, and some patients showed a poor prognosis despite having received proper medical treatment [2-4]. We herein describe a case of pulmonary hypertension in a patient with neurofibromatosis type I who had no identified risk factors of pulmonary hypertension. To our knowledge, this is the first such report in Korea.

Abordaje clínico de variantes fenotípicas en neurofibromatosis de tipo 1 / Clinical approach of phenotype variants in neurofibromatosis type 1

La neurofibromatosis de tipo 1 es una enfermedad genética de herencia autosómica dominante, de afectación multisistémica y gran variabilidad fenotípica, causada por una mutación del gen NF1 localizada en el cromosoma 17 q11.2 que afecta la codificación de la neurofibromina. La prevalencia mundial se estima en 1 de cada 4.000 a 5.000 individuos. En Colombia se desconoce su prevalencia. Los criterios diagnósticos establecidos por los National Institutes of Health incrementaron la sensibilidad diagnóstica para pacientes con neurofibromatosis de tipo 1, quienes presentan manifestaciones clínicas cutáneas y extracutáneas, para las cuales se propone una clasificación en siete grupos, según el sistema u órgano afectado, y en tres tipos de variantes clínicas: tumores, alteraciones esqueléticas y alteraciones oftalmológicas. Se describe la disponibilidad de pruebas diagnósticas y asesoría genética.

Mutational Analysis of the NF1 Gene in Two Families with Neurofibromatosis 1 Accompanied by Pheochromocytoma

Neurofibromatosis type 1 (NF1) is one of the most common autosomal dominant inherited disorders affecting the nervous system. NF1 is associated with mutations in the NF1 gene, which is located on chromosome sub-band 17q11.2 and contains 57 exons spanning approximately 300 kb of genomic DNA. NF1 is caused by a loss of function mutation of the NF1 gene, a tumor suppressor gene, which encodes for neurofibromin, a GTPase-activating protein (GAP) involved in the negative regulation of Ras activity. The GAP-related domain, which is encoded for by exons 20-27a, is one of the most important functional domains in neurofibromin. The cysteine-serine-rich domain has been recognized as an important functional domain in NF1-related pheochromocytomas. As the result of many genetic analyses of NF1-related pheochromocytomas, pheochromocytoma has generally been recognized as a true component of NF1. We recently experienced two families with NF1 accompanied by pheochromocytoma. The proband of family 1 is a 31-year-old female diagnosed with NF1 and pheochromocytoma. Gene analysis of the proband and her sister showed that the mutation of the NF1 gene (c.7907+1G>A) led to the skipping of exon 53 during NF1 mRNA splicing. The proband of family 2 is a 48-year-old male who was diagnosed with the same condition. Gene analysis demonstrated the mutation of the NF1 gene (c.5206-8C>G) with missplicing of exon 37. These novel germline mutations did not fall into the GAP-related nor the cysteine-serine-rich domains, but into the C-terminal area of the NF1 gene. This suggests that the correlation between the genotype and phenotype of NF1-related pheochromocytoma is somewhat difficult to characterize. Further studies will be necessary to confirm the function of the C-terminal area of the NF1 gene and its contribution to the development of NF1 and pheochromocytoma.

Neurofibromatosis tipo 1 (NF1): [revisión] / Neurofibromatosis type 1 (NF1): [review]

La neurofibromatosis tipo 1 es la genodermatosis más común, heredada de manera autosómica dominante. Presenta una distribución mundial y no tiene predominio racial. Afecta fundamentalmente la piel, los ojos y los sistemas nervioso y esquelético. El presente trabajo consiste en una revisión sobre su patogénesis, manifestaciones clínicas, criterios diagnósticos, tratamiento y pronóstico.

Neurofibromatosis type 1 is the most common genodermatosis, inherited in an autosomal dominant way. It has a worldwide distribution and has no racial predilection. Skin, eyes, nervous system and bones are usually affected. The present work reviews its pathogenesis, clinical manifestations, diagnostic criteria, treatment and prognoses.

Neurofibromina: qué hay de nuevo / Neurofibromin: what's new

La neurofibromina es una proteína citoplasmática codificada por el gen NF1, localizado en el cromosoma 17q11.2. Participa en la regulación de diversas vías de señalización molecular: MAPK, P13K, Caveolina y PKA. Cada vía cumple una función particular, con un objetivo final común, el control de genes involucrados en el crecimiento, apoptosis, diferenciación y migración celular. Realizamos una revisión sobre la neurofibromina, las vías de señalización en las que está implicada y su relación con las manifestaciones clínicas de la neurofibromatosis.

Congestive heart failure due to an iatrogenic arteriovenous fistula in a patient with neurofibromatosis-1 / 대한내과학회지

A 39-year-old woman, who 3 months prior had undergone sono-guided biopsy for pelvic masses, was admitted to our hospital with dyspnea. After the procedure, a large arteriovenous (AV) fistula was detected. The patient developed dyspnea with pain and swelling of the right leg and subsequently visited our hospital. Multiple cafe-au-lait spots and subcutaneous nodules were noted and a continuous bruit was heard in the right pelvic area. Transthoracic echocardiography revealed marked dilatation of the right atrium, right ventricle, and inferior vena cava. An angiogram showed multiple AV fistulas between the right iliac arteries and veins. The patient underwent aortoiliofemoral bypass surgery. Follow-up echocardiography after surgery showed dramatic improvement in heart function. Molecular analysis revealed a novel variation (c.4270-1G>a) at the 24th intron-exon splicing consensus sequence of the neurofibromin 1 (NF1) gene. This is a rare case of AV fistula that developed after biopsy and caused right-sided heart failure in a patient with neurofibromatosis.

Neurofibromatosis: the role of guanosine triphosphatase activating proteins in sensory neuron function / 生理学报

Neurofibromatosis type 1 (NF1) is a common autosomal dominant disease characterized by formation of multiple benign and malignant tumors. People with this disorder also experience chronic pain, which can be disabling. Neurofibromin, the protein product of the Nf1 gene, is a guanosine triphosphatase activating protein (GAP) for p21Ras (Ras). Loss of Nf1 results in an increase in activity of the Ras transduction cascade. Because of the growing evidence suggesting involvement of downstream components of the Ras transduction cascade in the sensitization of nociceptive sensory neurons, we examined the stimulus-evoked release of the neuropeptides, substance P (SP) and calcitonin gene-related peptide (CGRP), from primary sensory neurons of mice with a mutation of the Nf1 gene (Nf1+/-). Measuring the levels of SP and CGRP by radioimmunoassay, we demonstrated that capsaicin-stimulated release of neuropeptides is 3-5 folds higher in spinal cord slices from Nf1+/- mice than that from wildtype mouse tissue. In addition, the potassium- and capsaicin-stimulated release of CGRP from the culture of sensory neurons isolated from Nf1+/- mice was more than double that from the culture of wildtype neurons. Using patch-clamp electrophysiological techniques, we also examined the excitability of capsaicin-sensitive sensory neurons. It was found that the number of action potentials generated by the neurons from Nf1+/- mice, responding to a ramp of depolarizing current, was more than three times of that generated by wildtype neurons. Consistent with that observation, neurons from Nf1+/- mice had lower firing thresholds, lower rheobase currents and shorter firing latencies compared with wildtype neurons. These data clearly demonstrate that GAPs, such as neurofibromin, can alter the excitability of nociceptive sensory neurons. The augmented response of sensory neurons with altered Ras signaling may explain the abnormal pain sensations experienced by people with NF1 and suggests an important role of GAPs in the mechanism of sensory neuron sensitization.