What is Neurofibromatosis?

What is Neurofibromatosis?

Neurofibromatosis is a group of three different congenital conditions (present at birth). These are neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2), and schwannomatosis. Medical professionals characterize neurofibromatosis conditions by the growth of tumors in the nervous system, such as the brain, spinal cord, and other body parts. Most tumors are noncancerous (benign), but some may become cancerous (malignant).

Neurofibromatosis symptoms are typically mild to moderate. Complications can include learning impairment, hearing or vision loss, heart and blood vessel problems, pain, and sometimes cancer.

There is no known cure for neurofibromatosis, but there are available treatments . Many children may not need treatment other than a regular evaluation by a specialist. Other patients may need medication to reduce pain or surgery to remove the tumors.

Types of Neurofibromatosis


There are three types of neurofibromatosis conditions:

  • Neurofibromatosis type 1 (NF1) is the most common of the three conditions and is usually diagnosed in childhood. Signs are often visible at birth or infancy. Children and adults with NF1 can have various mild or moderate symptoms and medical problems that can develop over time.
  • Neurofibromatosis type 2 (NF2) is less common than NF1. Signs and symptoms of NF2 are related to benign tumors called vestibular schwannomas that grow in the ears and cause hearing loss or ringing in the ears, vision issues or loss, and nerve problems.
  • Schwannomatosis (SWN) is the least common type of neurofibromatosis. Like NF2, schwannomatosis is characterized by multiple noncancerous (benign) tumors called schwannomas, which grow on nerves. Symptoms usually appear in early adulthood and may cause pain, numbness, weakness, tingling, and headaches.

Signs & Symptoms of Neurofibromatosis


The signs and symptoms of each of the three types of neurofibromatosis are different and include the following:

Neurofibromatosis type 1 (NF1) symptoms

Signs and symptoms of NF1 include:

  • Café au lait spots, flat, light brown spots on the skin, are the most common sign of NF1. Café au lait spots are harmless and are usually present at birth or appear in infancy.
  • Neurofibromas are benign tumors that usually develop on or under the skin but can also grow inside the body. The number of neurofibromas may increase over time, and when they appear on the face can cause disfigurement.
  • Freckling in the armpits or groin area is smaller than café au lait spots and appears around age 3 to 5.
  • Optic gliomas are tumors that grow on the optic nerve and usually appear by age 6. These tumors can sometimes affect vision.
  • Lisch nodules or iris hamartomas are harmless bumps on the iris of the eye that do not affect vision.
  • Bone deformities such as abnormal bone development can cause scoliosis (a curved spine) or a bowed leg.
  • Large head and short stature may occur in children who have NF1. They tend to have a larger-than-average head and are typically shorter than average.
  • Learning disabilities including mild learning disability and attention-deficit/hyperactivity disorder (ADHD) as well as speech delay are common in children with NF1.

Neurofibromatosis type 2 (NF2) symptoms

Symptoms of NF2 are caused by benign tumors in the ears and are typically first noticed in the late teen years. Symptoms include:

  • Hearing loss or ringing in the ears (tinnitus), the main symptoms of NF2
  • Balance issues
  • Vision problems
  • Seizures
  • Numbness and weakness in the arms or legs
  • Headaches

Schwannomatosis symptoms

Symptoms of schwannomatosis usually appear between ages 25 and 30 and include:

  • Chronic pain that can be severe in different parts of the body
  • Numbness or weakness in different parts of the body
  • Loss of muscle

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What Causes Neurofibromatosis?


The exact causes of the three types of neurofibromatosis are unknown. They appear to involve genetic mutations (changes) that are passed on from a parent to a child or occur during development before birth. The genetic mutation for each type of neurofibromatosis is different.

Risk Factors for Neurofibromatosis

Risk Factors

The main risk factor for neurofibromatosis is a family history of the disorder. Parents pass on genetic mutations to children. A child of a parent who has NF1 or NF2 has a 50% chance of inheriting the genetic mutation. The risk of inheriting schwannomatosis from a parent who carries the mutation is lower.



Complications that may arise from neurofibromatosis are specific for each condition and depend on the location of the tumors.

NF1 complications

  • Learning difficulties. About half of the children with NF1 have attention deficit hyperactivity disorder (ADHD) , and some children develop other learning difficulties.
  • Bone development abnormality. In some children, bones develop abnormally and can cause scoliosis (curvature of the spine) or a curved leg. NF1 is also associated with an increased risk of osteoporosis (weak bones).
  • Vision problems. A tumor may develop on the optic nerve (optic glioma). It typically doesn’t cause problems but can sometimes affect vision.
  • High blood pressure (hypertension). Some children and adults with NF1 develop high blood pressure that requires medical attention.
  • Cancer. Tumors are a serious complication that can result from NF1. People who have NF1 should start screening for cancer at an earlier age than the general population.

NF2 complications

  • Deafness. Total or partial deafness can occur in people with NF2.
  • Facial nerve damage. Tumor growth of vestibular schwannoma (VS) (nearly always present in NF2 only ) or treatment of VS can cause facial nerve damage in people with NF2.
  • Vision problems. People with NF2 may develop cataracts at a relatively early age as well as other vision issues.
  • Peripheral neuropathy. Individuals with NF2 may develop problems with nerve function, usually resulting in numbness and weakness in the arms and legs.

Schwannomatosis complications

  • The pain caused by schwannomatosis can require management by a pain specialist and sometimes surgery to remove the tumors.
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Trust NewYork-Presbyterian for Neurofibromatosis Care

At NewYork-Presbyterian, our experienced pediatric neurologists and neurosurgeons work together to care for children with different neurological diseases and disorders. Learn about our diagnostic services and treatment options for neurofibromatosis, and contact us to make an appointment.