Neurofibromatosis Type 1 (NF1)
NF1 is usually diagnosed in childhood. Signs and symptoms are often noticeable at birth or shortly afterward, and almost always by age 10. They can vary in severity but are typically mild to moderate. Common signs and symptoms include:
- Flat, light brown spots on the skin (café-au-lait spots): These harmless spots are common in many people. Having more than six café-au-lait spots suggests NF1. They are usually present at birth or appear during the first years of life and stop appearing after childhood.
- Freckling in the armpits or groin area: Freckling usually appears by ages 3 to 5. Freckles are smaller than café-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), which, 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 with 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 are also common.
- Larger-than-average head size: Children with NF1 tend to have a larger head size due to increased brain volume.
- Short stature: Children with NF1 are often below average in height.
Neurofibromatosis Type 2 (NF2)
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. They include:
- Gradual hearing loss
- Ringing in the ears (tinnitus)
- Poor balance
- Headaches
Sometimes, NF2 can lead to the growth of schwannomas in other nerves, including the cranial, spinal, visual (optic), and peripheral nerves. Other benign tumors may also develop. 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
- Headaches
Schwannomatosis
This rare type of neurofibromatosis usually affects people after age 20, with symptoms typically appearing 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 usually do not grow on both hearing nerves, so people with schwannomatosis do not experience the same hearing loss as those with NF2. Symptoms include:
- Chronic pain: This can occur anywhere in the body and can be disabling.
- Numbness or weakness: This can affect various parts of the body.
- Loss of muscle
