Neurocutaneous syndromes

Neurocutaneous syndromes are genetic disorders that lead to abnormal growth of tumors in various parts of the body. These disorders usually first appear as skin lesions like birthmarks, but can eventually lead to tumors that affect the central nervous system and other parts of the body. While some conditions can be diagnosed at birth, others don't produce symptoms until later in life.
These diseases are caused by the abnormal development of cells in the earliest stages of an embryo's development. Although there is no cure for any of the neurocutaneous syndromes, treatments are available to help a child manage the symptoms and any health problems that they can cause.
What Are the Types of Neurocutaneous Syndromes?
There are several neurocutaneous syndromes, but the most common ones that involve children include:
• neurofibromatosis, types 1 and 2 (NF1 and NF2)
• Sturge-Weber syndrome
• tuberous sclerosis (TS)
• ataxia-telangiectasia (A-T)
• von Hippel-Lindau disease (VHL)
Symptoms vary widely from condition to condition, and they affect different kids in different ways. Often, the full effects of these diseases - even if they are detected at birth - do not emerge until the child grows up. The educational, social, and physical problems that the conditions cause must be managed throughout a child's life.
Neurofibromatosis
Neurofibromatosis is one of the most common neurocutaneous syndromes. It can cause tumors to grow on a child's nerve cells, producing skin changes, bone deformities, eye problems, and other complications, particularly in the brain.
Neurofibromatosis is usually inherited, but up to half of new cases occur because of changes (mutations) within a person's genes. Once a mutation has taken place, the changed (mutant) gene can then be passed on to succeeding generations. The child of a parent with neurofibromatosis has a 50% chance of having the disease.
There are two different kinds of this disorder, neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). NF1 accounts for approximately 90% of all cases.
Neurofibromatosis Type 1
NF1 occurs in about 1 in 4,000 babies born in the United States. When diagnosing NF1, doctors typically take a thorough medical history because children with NF1 often have a parent with the disease. NF1 is also known as von Recklinghausen disease.
The classic sign of NF1 is a skin pigment problem known as "café-au-lait" spots. These light brown, coffee-colored patches may be present at birth and may look like freckles at first. The spots increase in size and number during the first few years of life. A child diagnosed with NF1 will usually have at least six café-au-lait spots that are larger than freckles.
Another common sign of NF1 is the presence of Lisch nodules, tiny, benign (noncancerous) tumors found on the iris of the eye. In rare cases, tumors can develop along the optic nerves and affect a child's vision. During puberty, benign tumors called neurofibromas develop on or under the skin or along the nerves of the body. Bone deformities also may develop.
Treatment of a child with NF1 focuses on managing the symptoms. If a child has complications involving the eye, nervous system, spine, or bones, he or she will be referred to an appropriate specialist for treatment. In cases where these neurofibromas are causing chronic pain, growing into vital body organs, or causing infections, the growths can be removed through surgery.
Children with NF1 also have a high incidence of seizures, learning disabilities, attention deficit disorder, and speech problems. Therapy and specialists are available to manage those symptoms.
Neurofibromatosis Type 2
Neurofibromatosis type 2 is less common. It occurs in about 1 in 40,000 births. Kids who have this disease typically develop tumors on the auditory nerves (the nerves leading to the ear).
The symptoms of NF2, which typically appear in the teen years or early twenties, can include hearing loss, ringing of the ears, and problems with balance. Different treatment options are available to help a child manage these problems.
Tuberous Sclerosis
Tuberous sclerosis, or TS, is a disorder that causes benign growths called tubers to form on several different body organs, including the brain, eyes, kidneys, heart, skin, and lungs. It occurs in approximately 1 in 6,000 births. There is a 50% chance that the child of a parent with TS will have the disease.
The condition is often first recognized when a child has seizures or shows developmental delays. The severity of TS symptoms vary greatly between kids, ranging from mild skin abnormalities to mental retardation or kidney failure.
Treatment of TS usually includes medication to prevent seizures, treatments to address skin problems, surgery to remove tumors, and the management of high blood pressure caused by kidney disease.
Sturge-Weber Syndrome
Sturge-Weber syndrome is a rare condition that affects the skin and the brain. It is caused by a spontaneous genetic mutation. It is not passed down by parents who carry the disease. Because it frequently goes undiagnosed, it is difficult to estimate how many people currently have the disease.
Each case of Sturge-Weber is unique and symptoms vary widely from child to child. The most visible marker of the disease is a facial birthmark or "port wine stain" that appears when the child is born. It usually covers at least one upper eyelid and the forehead area.
Sturge-Weber syndrome can lead to neurological problems, including unusual blood vessel growths on the brain called angiomas. These growths often cause seizures that begin before a child's first birthday and can worsen with age. A child also may experience convulsions on the side of the body that's opposite from the port-wine stain.
About 30% of patients with Sturge-Weber also develop glaucoma (increased pressure inside the eye that impairs vision), typically in the eye that is affected by the port-wine stain. That eye might also be enlarged (a condition called buphthalmos). Some kids who suffer from this disease also experience strokes.
Treatments, medications, and surgery can help a child cope with the health problems associated with the disease.
Children as young as 1 month old who have Sturge-Weber can undergo laser treatment to reduce or remove port-wine stains. Anticonvulsant medication may be used to control seizures associated with the disorder, and surgery is available to control glaucoma and vision problems.
Ataxia Telangiectasia
Ataxia telangiectasia is a progressive degenerative disease that involves a large number of major body systems. It is a recessive genetic disease, meaning that both parents carry the gene that could combine to cause A-T in their children but do not have the disease themselves. Two parents with the mutated gene have a 25% chance of having a child affected by A-T.
A-T is usually noticed in the second year of life as a child develops problems with balance and slurred speech caused by ataxia (lack of muscle control). The ataxia occurs because the cerebellum, the part of the brain that controls muscle movement, is degenerating. Eventually, the lack of muscle control becomes severe enough for the child to require a wheelchair.
Another symptom of A-T is the appearance of tiny, red, spiderlike veins in the corners of the eyes or on the ears and cheeks when exposed to sunlight. The veins are known as telangiectases, and they are harmless.
About 70% of children with A-T also have immune system problems that make them more susceptible to chronic upper respiratory infections, lung infections, and pneumonia. Children with A-T are also very susceptible to developing certain cancers, such as leukemia and lymphoma.
Currently, no treatment is available for A-T and there is no way to stop its progression. But treatment is available to help kids manage their symptoms. Physical therapy and occupational therapy may help maintain flexibility, and speech therapy can help address slurring and other speech problems. Special medications may be given to help enhance weakened immune systems.
Von Hippel-Lindau Disease
Von Hippel-Lindau disease, or VHL, is a genetic disorder involving the abnormal growth of blood vessels. It usually occurs in certain areas of the body, such as the brain and other parts of the central nervous system, the retina of the eye, the adrenal glands, the kidneys, or the pancreas. The prevalence of the disease is unknown, but the child of a parent who carries the gene that causes VHL has a 50% chance of having the disorder.
Blood vessels usually grow like branches on a tree, but in kids with VHL, the vessels form small tumors called angiomas. Doctors carefully monitor angiomas because, depending on where they are located, they can cause other medical problems. For example, angiomas on the retina of the eye may lead to vision loss.
Symptoms of VHL typically appear when a person is between 10 and 30 years old. VHL is diagnosed using a special imaging technique called magnetic resonance imaging (MRI) or a computerized tomography (CT) scan. A thorough physical examination and blood tests are also performed.
The symptoms of VHL, which depend on the size and location of the angiomas, can include headaches, balance problems, dizziness, weakness, vision problems, and high blood pressure. Fluid-filled cysts or tumors (benign or cancerous) may develop around the angiomas, worsening these symptoms. People with this disorder have a higher risk of developing cancer, especially kidney cancer.
VHL treatment will depend on the size and location of the angiomas. The goal of treatment is to treat the tumors while they are small and before they put pressure on any of the major organs, such as the brain, or on the spine. Surgery may be required to remove the tumors before they create severe problems.
The prognosis for VHL patients depends on the location of the tumors and the complications they cause. Fortunately, early detection and treatment can improve a child's treatment outcome.
Caring for Your Child
The illnesses associated with neurocutaneous syndromes can place enormous stress and emotional burdens on you and your child, and it is easy to feel overwhelmed. Early intervention is important to helping your child achieve the best quality of life possible.
The focus of treatment is to prevent or minimize complications and maximize the child's strengths. Keep in mind the following tips:
• Positive reinforcement can strengthen your child's self-esteem and foster a sense of independence. Let your child find out what he or she is capable of, especially when performing daily living skills.
• Support groups for you and your child can be extremely beneficial, so seek out local chapters that address your child's particular illness (for a partial listing, click on the Additional Resources tab). Not only do these groups provide a supportive social environment, they also are a great way to share knowledge and resources.
• Psychotherapy or other supportive treatments can boost your child's self-esteem and coping skills, so ask your child's treatment team for appropriate referrals. Therapy also can help you and other family members deal with the stress involved in caring for a child with a chronic illness or disability.
• Physical, occupational, or speech therapy can help your child improve some of the developmental delays caused by his or her specific illness.
• Check with your local hospital or university for seminars or informational classes about neurocutaneous syndromes. By educating yourself and your family members, you can become a valuable resource in your child's long-term treatment.
A number of medical professionals may care for your child during diagnosis and treatment. These professionals can include a family practitioner, pediatrician, neurologist, neurosurgeon, orthopedic surgeon, oncologist, and ophthalmologist. A genetic counselor also may help by providing you with information about genetic testing and the risk of passing the disease on to another child.
Remember that although each of these conditions is challenging, supportive therapies and treatments are available to help both you and your child.