Question: What is (are) Neurofibromatosis type 1 ?
Answer: Neurofibromatosis type 1 (NF1) is a rare, inherited condition that is characterized primarily by changes in skin coloring and the development of multiple benign tumors along the nerves of the skin, brain, and other parts of the body. The severity of the condition and the associated signs and symptoms vary significantly from person to person. NF1 is caused by changes (mutations) in the NF1 gene and is inherited in an autosomal dominant manner. In approximately 50% of cases, the condition is inherited from an affected parent. Other cases may result from new (de novo) mutations in the gene which occur in people with no history of the condition in their family. Treatment is based on the signs and symptoms present in each person.
Source: GARD

Question: What are the symptoms of Neurofibromatosis type 1 ?
Answer: What are the signs and symptoms of Neurofibromatosis type 1? People affected by neurofibromatosis type 1 (NF1) have an increased risk of developing many different types of tumors (both cancerous and noncancerous). Almost all people with NF1 have neurofibromas, which are benign tumors that can affect nearly any nerve in the body. Most will develop these tumors on or just underneath the skin; however, neurofibromas can also grow in other places in the body and may even affect multiple nerves. Malignant peripheral nerve sheath tumors, which also grow along the nerves throughout the body, are the most common cancerous tumor found in people with NF1 and occur in approximately 10% of affected people. In children with NF1, the most common tumors are optic glioma (tumors that grow along the nerve leading from the eye to the brain) and brain tumors. Optic gliomas associated with NF1 are often asymptomatic although they can lead to vision loss. Other features of NF1 may include: Caf au lait spots (flat patches on the skin that are darker than the surrounding area) Freckling, especially in the underarm and groin Lisch nodules (clumps of pigment in the colored part of the eye that do not interfere with vision) Learning disabilities Seizures Autism spectrum disorder High blood pressure Short stature An unusually large head (macrocephaly) Skeletal abnormalities such as scoliosis GeneReview's Web site offers more specific information about the features of NF1. Please click on the link to access this resource. The Human Phenotype Ontology provides the following list of signs and symptoms for Neurofibromatosis type 1. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Cafe-au-lait spot 100% Lisch nodules 95% Benign neoplasm of the central nervous system 90% Generalized hyperpigmentation 90% Hypermelanotic macule 90% Kyphosis 90% Melanocytic nevus 90% Multiple lipomas 90% Neoplasm of the skin 90% Attention deficit hyperactivity disorder 50% Freckling 50% Hearing impairment 50% Heterochromia iridis 50% Incoordination 50% Memory impairment 50% Migraine 50% Neurological speech impairment 50% Paresthesia 50% Proptosis 50% Skeletal dysplasia 50% Slender long bone 50% Short stature 31% Plexiform neurofibroma 30% Specific learning disability 30% Abnormality of the respiratory system 7.5% Arterial stenosis 7.5% Glaucoma 7.5% Hydrocephalus 7.5% Hypertension 7.5% Hypopigmented skin patches 7.5% Leukemia 7.5% Limitation of joint mobility 7.5% Macrocephaly 7.5% Neoplasm of the gastrointestinal tract 7.5% Neuroendocrine neoplasm 7.5% Precocious puberty 7.5% Sarcoma 7.5% Scoliosis 7.5% Seizures 7.5% Tall stature 7.5% Urinary tract neoplasm 7.5% Visual impairment 7.5% Tibial pseudoarthrosis 4% Aqueductal stenosis 1.5% Genu valgum 1.5% Hypsarrhythmia 1.5% Optic glioma 1.5% Renal artery stenosis 1.5% Spinal neurofibromas 1.5% Meningioma 1% Pheochromocytoma 1% Astrocytoma - Autosomal dominant inheritance - Axillary freckling - Hypertelorism - Inguinal freckling - Intellectual disability, mild - Neurofibrosarcoma - Overgrowth - Parathyroid adenoma - Rhabdomyosarcoma - Spina bifida - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: Is Neurofibromatosis type 1 inherited ?
Answer: How is neurofibromatosis type 1 inherited? Neurofibromatosis type 1 (NF1) is inherited in an autosomal dominant manner. This means that a person only needs a change (mutation) in one copy of the responsible gene in each cell to have a genetic predisposition to the tumors associated with NF1. In approximately half of cases, an affected person inherits the mutation from an affected parent. Other cases may result from new (de novo) mutations in the gene; these cases occur in people with no history of the disorder in their family. A person with NF1 has a 50% chance with each pregnancy of passing along the altered gene to his or her child.
Source: GARD

Question: How to diagnose Neurofibromatosis type 1 ?
Answer: Is genetic testing available for neurofibromatosis type 1? Although it is usually not necessary for diagnosis, genetic testing is available for NF1, the gene known to cause neurofibromatosis type 1. Carrier testing for at-risk relatives and prenatal testing are possible if the disease-causing mutation in the family is known. The Genetic Testing Registry (GTR) is a centralized online resource for information about genetic tests. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional. How is neurofibromatosis type 1 diagnosed? The diagnosis of neurofibromatosis type 1 (NF1) is usually based on the presence of characteristic signs and symptoms. Specifically, doctors look for two or more of the following features to make a diagnosis of NF1: Six or more cafe-au-lait spots (measuring more than 5 mm across in children and more than 15 mm across in adolescents and adults) Two or more neurofibromas of any type or one plexiform neurofibroma (a neurofibroma that involves many nerves) Freckling in the underarm and/or groin Optic glioma Two or more Lisch nodules (clumps of pigment in the colored part of the eye that do not interfere with vision) Bone abnormalities including sphenoid dysplasia (absence of bone surrounding the eye) or tibial pseudarthrosis (incomplete healing of a fracture) A parent, sibling, or child who has been diagnosed with NF1 Because many of the features associated with NF1 develop with age, it can sometimes take several years to make a diagnosis in children without a family history of the condition. Genetic testing for changes (mutations) in the NF1 gene is available, but it is often not necessary. Prenatal testing and preimplantation genetic diagnosis is only an option if the disease-causing mutation in the family is known.
Source: GARD

Question: What are the treatments for Neurofibromatosis type 1 ?
Answer: How might neurofibromatosis type 1 be treated? The treatment of neurofibromatosis type 1 (NF1) is based on the signs and symptoms present in each person. There is currently no way to prevent or stop the growth of the tumors associated with NF1. Neurofibromas located on or just below the skin that are disfiguring or irritating may be surgically removed. Malignant peripheral nerve sheath tumors are generally treated with complete surgical excision (when possible) although some cases may require the addition of chemotherapy and/or radiation therapy. Most optic gliomas associated with NF1 do not cause any symptoms and therefore, do not require treatment; however, optic gliomas that threaten vision may be treated with surgery and/or chemotherapy. Surgery may also be recommended to correct some of the bone malformations (such as scoliosis) associated with NF1. GeneReview's Web site offers more specific information regarding the treatment and management of NF1. Please click on the link to access this resource.
Source: GARD