Neurofibromatosis is part of a group of conditions known as
neurocutaneous disorders; these types of disorders are caused by abnormal cell
development and result in the formation of tumors. These tumors can grow on
nerves, causing problems with the skin, bones, eyes, and elsewhere.
There are two main subtypes: neurofibromatosis type 1 (NF1),
which accounts for about 90% of all cases of neurofibromatosis, and
neurofibromatosis type 2 (NF2), which is much less common. Neurofibromatosis is
generally an inherited disorder, but can be caused by spontaneous mutation. Once
the change in genes happens, it can be passed on.
Neurofibromatosis 1 (or NF1) occurs in about one in 3,000 to
4,000 births; the incidence of NF2 is much less. NF1 is also called von
Recklinghausen disease after a German pathologist involved in identifying the
composition of tumors associated with NF1.
What are some signs or symptoms associated with NF1?
- Café-au-lait spots (also called macules): These are flat patches of
light brown or coffee-colored skin. Initially, they might be present on an
infant and look like freckles, but may get bigger in size and more numerous
during a child’s first few years of life. A child with NF1 is likely to have
at least six or more of these spots bigger in size than freckles. The spots
themselves are not painful, and people who do not have neurofibromatosis can
have one or two café-au-lait spots.
- Lisch nodules: These are small noncancerous tumors located on the
iris (the colored part) of the eyes. Lisch nodules do not cause problems
with vision, but tumors might later develop in the eye. These tumors are
called optic gliomas; they may or may not affect vision.
- Neurofibromas: These are noncancerous tumors that are located mostly
on top of or under the skin. Neurofibromas may also grow on nerves. Some
people who have NF1 do develop cancerous tumors on nerves, called malignant
peripheral nerve sheath tumors (MPNST). A therapy that targets MPNST is
pirfenidone.
- High blood pressure (hypertension)
- Shortness (height)
- Macrocephaly (having an unusually big head)
- Bone abnormalities, such as scoliosis or tibial bowing
- Learning disabilities
- Attention deficit hyperactivity disorder (ADHD)
- Seizures
- Speech problems
- Many freckles under the armpit or in the groin region
There may be other complications associated with NF1, including
vascular conditions affecting the central and peripheral nervous systems.
How is neurofibromatosis type 1 treated?
NF1 can not be cured at this time, but symptoms can be followed
and managed. It is important to evaluate and identify tumors associated with
NF1. It is recommended that a person with NF1 has at least one annual regular
medical follow-up examination, along with an annual ophthalmologic examination.
Surgery can remove disfigurements caused by neurofibromas.
Recent studies have indicated that the cholesterol drug lovastatin may be useful
in treating learning disabilities and ADHD. A person with NF1 and his or her
family may find psychological and social support, and possibly genetic
counseling, useful.