Neurofibromatoses
(Diseases)
On this page, you will find everything you need to know about neurofibromatosis.
What is Neurofibromatosis?
Neurofibromatosis is a genetic disorder that affects the nervous system, including the brain, spinal cord, nerves, and skin. It is characterized by the growth of tumors called neurofibromas on nerves or under the skin. These tumors are usually benign (non-cancerous), but in rare cases, they may become malignant. It affects both males and females equally, across all ethnic groups.
What are the types of Neurofibromatosis?Neurofibromatosis Type 1 – NF1):
Neurofibromatosis is classified into three main types:
Neurofibromatosis Type 1 (NF1): Also known as Von Recklinghausen disease or peripheral neurofibromatosis, NF1 is the most common type, affecting about 1 in every 3,000 to 5,000 people. It is characterized by light brown patches on the skin known as caf-au-lait spots, as well as freckling in the armpit and groin areas. Neurofibromas form under the skin and may cause bone deformities such as scoliosis and tumors on the optic nerve. Symptoms often appear at birth or during childhood.Neurofibromatosis Type 2 – NF2):
Neurofibromatosis Type 2 (NF2): Also known as bilateral acoustic neurofibromatosis or central neurofibromatosis, NF2 is less common, affecting about 1 in every 25,000 to 40,000 people. It is characterized by benign tumors on the auditory nerves, which may lead to hearing loss, tinnitus, and balance problems. Symptoms may begin in childhood or adolescence and primarily affect the central nervous system, including the brain and spinal cord.
Schwannomatosis: Schwannomatosis is the rarest form of neurofibromatosis, affecting fewer than 1 in every 40,000 people. It is characterized by the development of benign tumors called schwannomas on nerves, leading to chronic and severe pain, and sometimes numbness or tingling in the limbs. Unlike NF1 and NF2, it usually does not cause visible skin changes or hearing loss. It is commonly diagnosed in adults over the age of 30.Schwannomatosis):
What are the symptoms of Neurofibromatosis?
Symptoms vary depending on the type:
Symptoms of NF1:
Light brown skin spots (caf-au-lait spots) before age five.NF1):
Freckling in the armpits and groin.
Small bumps in the iris (Lisch nodules).
Cutaneous or subcutaneous neurofibromas.
Learning difficulties, attention-deficit/hyperactivity disorder (ADHD).
Seizures.ADHD).
Optic nerve tumors may affect vision.
Headaches and frequent pain.
Spinal curvature (scoliosis).
Bone deformities, such as bowing of the legs.
Retinal tumors and, in rare cases, malignant tumors (e.g.,Malignant reticulofibroma malignant peripheral nerve sheath tumors in 10% of cases).
Heart and vascular problems, such as high blood pressure or vascular abnormalities.
Enlarged head and short stature.
Symptoms of NF2:
Progressive hearing loss due to tumors on the auditory nerves.NF2):
Tinnitus.
Balance issues.
Meningiomas.
Spinal cord tumors.
Peripheral neuropathy causes weakness and numbness.
Chronic headaches.
Muscle weakness and atrophy.
Early-onset cataracts.
Symptoms of Schwannomatosis:
Chronic pain anywhere in the body, possibly associated with schwannomas.Schwannomatosis):
Weakness, numbness, or tingling in the limbs.
Balance and vision issues.
Localized benign schwannomas on peripheral nerves or under the skin and are often localized to a single area of the body.
What causes Neurofibromatosis?
Neurofibromatosis is caused by genetic factors or spontaneous gene mutations. The primary cause is a defect in tumor-suppressor genes, leading to abnormal cell growth and tumor formation.
In about 50% of cases, it is inherited in an autosomal dominant pattern, meaning a single copy of the mutated gene from one parent is sufficient to cause the disorder. There is a 50% chance of passing it on to children.
In the remaining cases, spontaneous genetic mutations occur, with no family history. These mutations arise randomly during the formation of the egg or sperm and are not related to environmental or behavioral factors.
How is Neurofibromatosis diagnosed?
Diagnosis depends on clinical symptoms, medical examinations, and family history.
Diagnosis of NF1:
The physician takes the medical history, then performs a physical examination, and carries out some investigations as needed, such as:
Medical history and clinical examination.
Imaging tests: MRI, X-rays, orMRICT scans to detectCTtumors or skeletal abnormalities.
Genetic testing to identify mutations in theNFNF1 gene, especially if symptoms are unclear.
Diagnosis of NF2:
Medical history and clinical examination.
Hearing tests: including audiometry and brainstem auditory evoked response (BAER).
Imaging tests: MRI to detect tumorsMRIin the brain or peripheral nerves.
Genetic testing to confirm mutationsNFin the NF2 gene.
Additional tests for all types:
Blood tests to identify genetic abnormalities.
Biopsies of skin or nerve tumors for microscopic analysis.
Eye examinations to detect nodules in the iris or changes in vision.
How is Neurofibromatosis treated?
There is no definitive cure for neurofibromatosis. Treatment focuses on managing symptoms, improving quality of life, and preventing complications.
Surgical treatment:
Tumor Removal: Tumors are surgically removed if they cause severe pain, deformity, pressure on nearby organs, or if they grow rapidly.
Correction of Bone Deformities: Scoliosis is treated using a brace or spinal fusion surgery in severe cases. Leg bone fractures are treated with braces or bone grafting.
Radiation therapy:
Used to shrink or control tumor growth, especially in malignant cases.
Chemotherapy:
Used to treat malignant tumors orSelumetinibreduce tumor size before surgery.
Medication:
Selumetinib is approved for treating inoperable NF1-related tumors in children.
Pain management medications or drugs for related conditions, such as hypertension.
Assistive devices:
Auditory brainstem implants for NF2-related hearing loss,Auditory brainstem implants can be used to transmit sound signals directly to the brain.
Hearing aids or corrective lenses for hearing and vision support.
Physical and psychological therapy:
Physical therapy to improve mobility or manage bone problems.
Psychological support and pain management to improve quality of life.
Can Neurofibromatosis be prevented?
There is no known way to prevent neurofibromatosis. However, if you are planning to have children, genetic counseling is recommended to assess the risk of passing on a genetic condition such as neurofibromatosis.
What are the complications of Neurofibromatosis?
Complications may include:
Hearing loss due to auditory nerve tumors.
Vision loss caused by optic nerve tumors.
Chronic pain from tumor growth or nerve compression.
Learning and behavioral difficulties, including social challenges.
Heart and vascular issues, such as hypertension or congenital heart defects.
Low self-esteem due to visible skin fibromas or spots.
Increased risk of cancers, such as breast cancer or soft tissue sarcomas.
In rare cases, benign tumors may transform into malignant ones some neurofibromas may transform into malignant tumors..
When should you see a doctor? Consult a doctor if you notice symptoms such as:
Unusual skin spots.
Unexplained lumps under the skin.
Freckling in the armpits or groin.
Changes in hearing or vision.
Unexplained pain.
Muscle weakness.
Numbness or tingling in the hands or feet.
Frequently Asked Questions
What are the risk factors for neurofibromatosis?
