Symptoms

There are three types of neurofibromatosis, each with different signs and symptoms.

Neurofibromatosis 1

Neurofibromatosis 1 (NF1) is usually diagnosed during childhood. Signs are often noticeable at birth or shortly afterward and almost always by age 10. Signs and symptoms are often mild to moderate, but can vary in severity.

Signs and symptoms include:

• Flat, light brown spots on the skin (cafe au lait spots). These harmless spots are common in many people. Having more than six cafe au lait spots suggests NF1. They are usually present at birth or appear during the first years of life. After childhood, new spots stop appearing.
• Freckling in the armpits or groin area. Freckling usually appears by ages 3 to 5. Freckles are smaller than cafe au lait spots and tend to occur in clusters in skin folds.
• Tiny bumps on the iris of the eye (Lisch nodules). These harmless nodules can't easily be seen and don't affect vision.
• Soft, pea-sized bumps on or under the skin (neurofibromas). These benign tumors usually develop in or under the skin, but can also grow inside the body. Sometimes, a growth will involve many nerves (plexiform neurofibroma). Plexiform neurofibromas, when located on the face, can cause disfigurement. Neurofibromas may increase in number with age.
• Bone deformities. Abnormal bone development and a deficiency in bone mineral density can cause bone deformities such as a curved spine (scoliosis) or a bowed lower leg.
• Tumor on the optic nerve (optic glioma). These tumors usually appear by age 3, rarely in late childhood and adolescence, and almost never in adults.
• Learning disabilities. Impaired thinking skills are common in children who have NF1 but are usually mild. Often there is a specific learning disability, such as a problem with reading or mathematics. Attention-deficit/hyperactivity disorder (ADHD) and speech delay also are common.
• Larger than average head size. Children with NF1 tend to have a larger than average head size due to increased brain volume.
• Short stature. Children who have NF1 often are below average in height.

Neurofibromatosis 2

Neurofibromatosis 2 (NF2) is much less common than NF1. Signs and symptoms of NF2 usually result from the development of benign, slow-growing tumors in both ears (acoustic neuromas), which can cause hearing loss. Also known as vestibular schwannomas, these tumors grow on the nerve that carries sound and balance information from the inner ear to the brain.

Signs and symptoms generally appear during the late teen and early adult years, and can vary in severity. Signs and symptoms can include:

• Gradual hearing loss
• Ringing in the ears
• Poor balance
• Headaches

Sometimes NF2 can lead to the growth of schwannomas in other nerves, including the cranial, spinal, visual (optic) and peripheral nerves. People who have NF2 may also develop other benign tumors.

Signs and symptoms of these tumors can include:

• Numbness and weakness in the arms or legs
• Pain
• Balance difficulties
• Facial drop
• Vision problems or cataracts
• Seizures
• Headache

Schwannomatosis

This rare type of neurofibromatosis usually affects people after age 20. Symptoms usually appear between ages 25 and 30. Schwannomatosis causes tumors to develop on the cranial, spinal and peripheral nerves — but rarely on the nerve that carries sound and balance information from the inner ear to the brain. Tumors don't usually grow on both hearing nerves, so people who have schwannomatosis don't experience the same hearing loss as people who have NF2.

Symptoms of schwannomatosis include:

• Chronic pain, which can occur anywhere in the body and can be disabling
• Numbness or weakness in various parts of the body
• Loss of muscle

When to see a doctor

See your doctor if you or your child develop signs or symptoms of neurofibromatosis. The tumors associated with neurofibromatosis are often benign and slow growing.