Neurofibromatosis

Neurofibromatosis (NF) is a condition that causes tumors to grow on nerve tissue, producing skin and bone abnormalities.

NF is often diagnosed in childhood, occasionally in infancy (in children with severe cases), but usually around 3-16 years of age. Effects of the disease vary widely — some children live almost unaffected by the condition; rarely, others might be severely disabled.

There's no specific cure for NF, but tumors usually can be removed and related complications treated. Because learning disabilities occur in about half the children with NF, some might need extra help in the classroom.

About Neurofibromatosis

 Neurofibromatosis is a neurocutaneous syndrome passed down through the parents' genes, and it affects the brain, spinal cord, nerves, skin, and other systems in the body.

Neurofibromatosis is defined by tumors, called neurofibromas, that grow along nerves in the body, or on or under the skin. As the tumors increase in size, they can press on vital areas of the body, causing problems in the way the body functions.

Neurofibromas often first appear in childhood, especially during puberty. The first noticeable sign is almost always the presence of brown café au lait spots. These distinctive spots don't hurt or itch and never progress to anything more serious than spots. They can be found anywhere on the body, though not usually on the face. Tiny ones — freckles — may be seen under the arms or in the groin area.

Many neurofibromas can be removed. Although usually benign (noncancerous), an estimated 3%-5% become cancerous.

Of the two types of neurofibromatosis — NF1 and NF2 — NF1 is more common, occurring in 1 of every 4,000 births and affecting an estimated 100,000 Americans. It is also known as von Recklinghausen disease.

NF2 is characterized by the presence of bilateral acoustic neurofibroma-like tumors and is rarer, seen in 1 in 50,000 births. People with NF2 usually develop benign tumors on the nerves in their ears, causing hearing loss, eventual deafness, and problems with balance.

The severity of both types of neurofibromatosis varies greatly. In families where more than one person has NF, it can present with different physical signs and complications for each person. At diagnosis, it isn't possible to know right away whether a case will be mild or lead to severe complications.

Causes of NF

Both types of neurofibromatosis are autosomal dominant genetic disorders, which means an affected person has 1 chance in 2 of passing it on with each pregnancy. Neurofibromatosis also can be the result of a spontaneous change (mutation) in the genetic material of the sperm or egg at conception in families with no previous history of NF. About half of cases are inherited, and the other half are due to spontaneous genetic mutation.

NF 1 and NF 2 are each related to changes in separate genes. The NF1 gene is located on chromosome 17, and NF2 has been traced to chromosome 22. These findings are important because they may eventually lead to the development of a blood test or other genetic test to find out if a relative has NF.