Neurocutaneous Syndromes in Children
Overview
Neurocutaneous syndromes are
disorders that affect the brain, spinal cord, organs, skin, and bones. The diseases
are
lifelong conditions that can cause tumors to grow in these areas. They can also cause
other problems, such as hearing loss, seizures, and developmental problems. Each
disorder has different symptoms. The most common disorders in children cause skin
growths.
The 3 most common types of neurocutaneous syndromes are:
- Tuberous sclerosis (TS)
- Neurofibromatosis (NF), including NF1,
NF2, and schwannomatosis
- Sturge-Weber disease
Causes
These diseases are all present at
birth (congenital). They are caused by gene changes.
Tuberous sclerosis (TS) is an
autosomal dominant disorder. Autosomal means that both boys and girls are affected.
Dominant means that only 1 copy of the gene is needed to have the condition. A parent
with TS or the gene for TS has a 50% chance to pass the gene on to each child. Many
children born with TS are the first cases in a family. This is because most cases
of TS
are caused by a new gene change (mutation) and are not inherited. But the parents
of a
child with TS may have very mild symptoms of the disorder. The parents are believed
to
have a slightly increased risk of having another child with
TS.
Neurofibromatosis Type 1 (NF1)
occurs in about 1 in 3,000 to 4,000 babies in the U.S. NF1 is an autosomal dominant
disorder. It’s caused by changes in a gene on chromosome 17. In half of the cases,
this
is inherited from a parent with the disease.
Neurofibromatosis Type 2 (NF2) is
less common, is also an autosomal dominant disorder. It affects about 1 in 25,000
babies
in the U.S. The gene change that causes NF2 is on chromosome 22.
A parent with NF has a 1 in 2
chance of passing on the genetic mutation and disease to each child.
NF may also be the result of a new
gene change. From 3 in 10 to 1 in 2 cases of NF are caused by a new mutation and not
inherited. Boys and girls are equally affected.
Schwannomatosis is a form of NF.
It's rare, and only 3 in 20 cases are inherited. There are 2 genetic forms of
schwannomatosis:
-
Schwannomatosis 1. This is caused by mutations in either
the SMARCB1 or LZTR1 genes. This condition is also known as congenital cutaneous
neurilemmomatosis.
-
Schwannomatosis 2. This condition starts in adulthood. It
causes schwannomas (benign nerve tumors) to grow throughout the body. But it has no
other symptoms.
The cause of Sturge-Weber disease
is not known. Researchers think it occurs by chance (sporadic). In some cases, other
family members have hemangiomas. These are noncancer (benign) growths that are made
of
blood vessels. Some children with this condition may have mutations in a gene called
GNAQ.
Risk Factors
A child is more at risk for a
neurocutaneous syndrome if they have a family member with one of the syndromes.
Symptoms
Symptoms can occur a bit differently in each child. Below are the most common symptoms
for each condition:
Tuberous sclerosis
This causes growths called
tubers to grow in the brain and retina of the eye. Tuberous sclerosis also affects
many other organs in the body. It can affect the brain, spinal cord, lungs, heart,
kidneys, skin, and bones. Some of the symptoms include intellectual disability,
developmental delays, seizures, and learning disabilities. Areas of white skin
(called Chagrin patches) and other skin abnormalities may appear.
Neurofibromatosis Type 1 (NF1)
This is the more common type of
neurofibromatosis. It's also called Von Recklinghausen's disease. The classic symptom
of NF1 is light brown patches of pigment on the skin. These are known as cafe-au-lait
spots. A child may also have skin tumors that are not cancer (benign). These are
called neurofibromas. Neurofibromas are often found growing on the nerves and in
organs. There is a higher rate of brain tumors in people with NF. Less than 1 in 100
people with NF1 will have cancer (malignant) in the neurofibromas. An older child
may
also have Lisch nodules. These are small tumors on the colored part of the eye
(iris). These usually do not cause problems. Other symptoms can include hearing loss,
headaches, seizures, scoliosis, and facial pain or numbness. Intellectual
disability of varying degree may be slightly more common in people with NF1. About
half may have a variety of learning problems and attention deficit disorder. Renal
artery stenosis and other vascular problems may occur with NF1.
Neurofibromatosis Type 2 (NF2)
NF2 affects about 1 in 25,000
people. The symptoms usually appear between ages 18 and 22. The tumors called
schwannomas grow on a vestibular nerve branch. These are known as bilateral
vestibular schwannomas. These tumors on the 8th cranial nerve can lead to hearing
loss, headaches, problems with facial movements, problems with balance, and trouble
walking. A child may have hearing loss. Other signs of NF2 may include seizures,
tumors of the membranes around the brain and spinal cord (meningiomas), skin nodules
(neurofibromas), cataract, and cafe-au-lait spots.
Schwannomatosis
This type of neurofibromatosis
causes schwannomas to grow through the body, but without other symptoms of NF1 or
NF2. A schwannoma is a tumor of the peripheral nervous system that happens in the
nerve’s protective covering known as the nerve sheath.
The main symptom is intense pain
that occurs when a schwannoma grows larger or presses on a nerve or nearby tissue.
Other symptoms may include numbness, tingling, or weakness in the fingers and
toes.
Sturge-Weber disease
The classic symptom of this
disease is a mark on a child’s face called a port wine stain. A port wine stain is
a
flat area on the skin that varies in color from red to dark purple. It's present from
birth. It's most often found near or around the eye and forehead. The birthmark is
caused by too many tiny blood vessels forming under the skin. There may also be
related brain abnormalities on the same side of the brain as the face lesion. A child
may also have seizures, muscle weakness, changes in vision, and intellectual
disability. A child may also have increased pressure in the eye (glaucoma) at birth.
Sturge-Weber disease does not affect the other organs of the
body.
The symptoms of neurocutaneous
syndromes can be like other health conditions. Make sure your child sees their
healthcare provider for a diagnosis.
Diagnosis
The healthcare provider will ask
about your child’s symptoms, health history, and developmental milestones. They may
also
ask about your family’s health history. They will give your child a physical exam.
Your
child may also have tests, such as:
-
Genetic tests. These are blood or saliva tests. They check
for health conditions that tend to run in families.
-
MRI. This test uses large magnets, radio waves, and a
computer to make images of the inside of the body.
-
CT scan. This test uses a series of X-rays and a computer
to create images of the inside of the body. A CT scan shows more detail than a
regular X-ray.
-
Electroencephalogram (EEG). This test records the brain's
electrical activity through sticky pads (electrodes) attached to the scalp.
-
Eye exam. This is done to check for growths on the retina,
cataract, or excess pressure in the eye.
-
Biopsy. A small sample of tissue from a tumor or skin
lesion may be taken. This is checked with a microscope.
Treatment
Treatment will depend on your child’s symptoms, age, and general health. It will also
depend on how severe the condition is. Neurocutaneous syndromes are lifelong conditions
that have no cure. Because of this, your child’s healthcare providers will work to:
- Manage symptoms such as seizures
- Prevent or lessen problems
- Make the most of a child's abilities
A child is treated by a healthcare team that may include:
-
Pediatrician or family healthcare provider. This is a
child’s primary healthcare provider.
-
Neurologist. This is a healthcare provider who treats
conditions of the brain, spinal cord, and nerves.
-
Neurosurgeon. This is a surgeon who treats the brain and
spinal cord.
-
Orthopedic surgeon. This is a surgeon who treats muscles,
ligaments, tendons, and bones.
-
Ophthalmologist. This is a healthcare provider who treats
eye problems.
-
Oncologist. This is a healthcare provider who treats
cancer and other tumors.
-
Rehabilitation team. This team may include physical,
occupational, speech, and audiology therapists. It may also include nurses, and
social workers.
Treatment varies as needed. In some cases, surgery may be done to remove tumors that
may be cancer or for cosmetic reasons.
Talk with your child’s healthcare providers about the risks, benefits, and possible
side effects of all treatments.
Prevention
Your healthcare provider may advise genetic counseling. You can discuss with a counselor
the risk for a neurocutaneous syndrome in a future pregnancy.
Living with
A neurocutaneous syndrome is a
lifelong condition that has no cure. Your child’s healthcare providers will work to
prevent deformities or keep them to a minimum. They will also work to help your child
make the most of their abilities. You can help your child strengthen their self-esteem
and be as independent as possible. Physical and occupational rehabilitation, plus
extra
support in school, can help a child function as well as possible.
The full extent of a neurocutaneous
syndrome is usually not completely known right after birth. It can become clearer
as a
child grows and develops. It's important to keep scheduled follow-up appointments
with
healthcare providers so ongoing observation and support can be given to both your
child
and family.
When to Call a Healthcare Provider
Call the healthcare provider if your child has:
- Symptoms that don’t get better, or get worse
- New symptoms
Key Points
Next Steps
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the visit, write down the name of a new diagnosis, and any new medicines, treatments,
or tests. Also write down any new instructions your provider gives you for your child.
- Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
- Know how you can contact your child’s
healthcare provider after office hours. This is important if your child becomes ill
and you have questions or need advice.