There is no agreed upon standard of treatment for neurosarcoidosis. Doctors generally recommend corticosteroid therapy as first-line therapy for individuals with the condition. Additional treatment with immunomodulatory drugs such as hydroxychloroquine, pentoxyfilline, thalidomide, and infliximab, and immunosuppressive drugs such as methotrexate, azathioprine, cyclosporin, and cyclophosphamide, have benefited some individuals. While the use of corticosteroids and other immunosuppressive drugs is effective, these medications also have undesirable side effects. Side effects and experience with certain drugs may play a role in medication choices.


The prognosis for patients with neurosarcoidosis varies. Approximately two-thirds of those with the condition will recover completely; the remainder will have a chronically progressing or on-and-off course of illness. Complications resulting from immunosuppressive treatments, such as cryptococcal and tuberculous meningitis, progressive multifocal leukoencephalopathy, and inclusion body myositis, may be fatal for a small percentage of individuals.


The National Institute of Neurological Disorders and Stroke (NINDS) has joined with other institutes of the National Institutes of Health (NIH) to form a trans-NIH working group to coordinate and fund research into the disease mechanisms of sarcoidosis, predisposing factors, genetic underpinnings, and the potential for clinical therapies. Grants are supporting research at major medical institutions across the country. The outcomes of this research will be better ways to diagnose, treat, and ultimately cure sarcoidosis and neurosarcardoisis.


Mitochondrial myopathies are a group of neuromuscular diseases caused by damage to the mitochondriasmall, energy-producing structures that serve as the cells' "power plants." Nerve cells in the brain and muscles require a great deal of energy, and thus appear to be particularly damaged when mitochondrial dysfunction occurs. Some of the more common mitochondrial myopathies include Kearns-Sayre syndrome, myoclonus epilepsy with ragged-red fibers, and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes. The symptoms of mitochondrial myopathies include muscle weakness or exercise intolerance, heart failure or rhythm disturbances, dementia, movement disorders, stroke-like episodes, deafness, blindness, droopy eyelids, limited mobility of the eyes, vomiting, and seizures. The prognosis for these disorders ranges in severity from progressive weakness to death. Most mitochondrial myopathies occur before the age of 20, and often begin with exercise intolerance or muscle weakness. During physical activity, muscles may become easily fatigued or weak. Muscle cramping is rare, but may occur. Nausea, headache, and breathlessness are also associated with these disorders.


Although there is no specific treatment for any of the mitochondrial myopathies, physical therapy may extend the range of movement of muscles and improve dexterity. Vitamin therapies such as riboflavin, coenzyme Q, and carnitine (a specialized amino acid) may provide subjective improvement in fatigue and energy levels in some patients.


The prognosis for patients with mitochondrial myopathies varies greatly, depending largely on the type of disease and the degree of involvement of various organs. These disorders cause progressive weakness and can lead to death.


The NINDS conducts and supports research on mitochondrial myopathies. The goals of this research are to increase scientific understanding of these disorders and to find ways to effectively treat, prevent, or potentially cure them.


Lissencephaly, which literally means "smooth brain," is a rare, gene-linked brain malformation characterized by the absence of normal convolutions (folds) in the cerebral cortex and an abnormally small head (microcephaly). In the usual condition of lissencephaly, children usually have a normal sized head at birth. In children with reduced head size at birth, the condition microlissencephaly is typically diagnosed. Lissencephaly is caused by defective neuronal migration during embryonic development, the process in which nerve cells move from their place of origin to their permanent location within the cerebral cortex gray matter. Symptoms of the disorder may include unusual facial appearance, difficulty swallowing, failure to thrive, muscle spasms, seizures, and severe psychomotor retardation. Hands, fingers, or toes may be deformed. Lissencephaly may be associated with other diseases including isolated lissencephaly sequence, Miller-Dieker syndrome, and Walker-Warburg syndrome. Sometimes it can be difficult to distinguish between these conditions clinically so consultation with national experts is recommended to help ensure correct diagnosis and possible molecular testing.


There is no cure for lissencephaly, but children can show progress in their development over time. Supportive care may be needed to help with comfort, feeding, and nursing needs. Seizures may be particularly problematic but anticonvulsant medications can help. Progressive hydrocephalus (an excessive accumulation of cerebrospinal fluid in the brain) is very rare, seen only in the subtype of Walker-Warburg syndrome, but may require shunting. If feeding becomes difficult, a gastrostomy tube may be considered.


The prognosis for children with lissencephaly depends on the degree of brain malformation. Many will die before the age of 10 years. The cause of death is usually aspiration of food or fluids, respiratory disease, or severe seizures. Some will survive, but show no significant development -- usually not beyond a 3- to 5-month-old level. Others may have near-normal development and intelligence. Because of this range, it is important to seek the opinion of specialists in lissencephaly and support from family groups with connection to these specialists.


The NINDS conducts and supports a wide range of studies that explore the complex systems of normal brain development, including neuronal migration. Recent studies have identified genes that are responsible for lissencephaly. The knowledge gained from these studies provides the foundation for developing treatments and preventive measures for neuronal migration disorders.


Multiple system atrophy with orthostatic hypotension is the current classification for a neurological disorder that was once called Shy-Drager syndrome. A progressive disorder of the central and autonomic nervous systems, it is characterized by orthostatic hypotension (an excessive drop in blood pressure when standing up) which causes dizziness or fainting. Multiple system atrophy can occur without orthostatic hypotension, but instead have urinary involvement (urgency/incontinence). Doctors classify the disorder into 3 types: the Parkinsonian-type includes symptoms of Parkinson's disease such as slow movement, stiff muscles, and tremor; the cerebellar-type, which causes problems with coordination and speech; and the combined-type, which includes symptoms of both parkinsonism and cerebellar failure. Problems with urinary incontinence, constipation, and sexual impotence in men happen early in the course of the disease. Other symptoms include generalized weakness, double vision or other vision disturbances, difficulty breathing and swallowing, sleep disturbances, and decreased sweating. Because the disease resembles others, a correct diagnosis may take years.


There is no cure for multiple system atrophy with orthostatic hypotension. Treatment is aimed at controlling symptoms. Anti-Parkinson medication such as Sinemet may improve the general sense of well-being. Medications to elevate blood pressure while standing are often used, but may cause high blood pressure when lying down. Individuals should sleep with the head of the bed elevated. An artificial feeding tube or breathing tube may be required for problems with swallowing and breathing.


Most individuals with multiple system atrophy with orthostatic hypotension die within 7 to 10 years after the onset of symptoms. A problem with the respiratory system is the most common cause of death.


The NINDS supports research on disorders of the autonomic nervous system, including multiple system atrophy with orthostatic hypotension. This research is aimed at developing techniques to diagnose, treat, and prevent these disorders. Currently there are ongoing treatment trials of drugs to treat MSA.


A transient ischemic attack (TIA) is a transient stroke that lasts only a few minutes. It occurs when the blood supply to part of the brain is briefly interrupted. TIA symptoms, which usually occur suddenly, are similar to those of stroke but do not last as long. Most symptoms of a TIA disappear within an hour, although they may persist for up to 24 hours. Symptoms can include: numbness or weakness in the face, arm, or leg, especially on one side of the body; confusion or difficulty in talking or understanding speech; trouble seeing in one or both eyes; and difficulty with walking, dizziness, or loss of balance and coordination.


Because there is no way to tell whether symptoms are from a TIA or an acute stroke, patients should assume that all stroke-like symptoms signal an emergency and should not wait to see if they go away. A prompt evaluation (within 60 minutes) is necessary to identify the cause of the TIA and determine appropriate therapy. Depending on a patient's medical history and the results of a medical examination, the doctor may recommend drug therapy or surgery to reduce the risk of stroke in people who have had a TIA. The use of antiplatelet agents, particularly aspirin, is a standard treatment for patients at risk for stroke. People with atrial fibrillation (irregular beating of the heart) may be prescribed anticoagulants.


TIAs are often warning signs that a person is at risk for a more serious and debilitating stroke. About one-third of those who have a TIA will have an acute stroke some time in the future. Many strokes can be prevented by heeding the warning signs of TIAs and treating underlying risk factors. The most important treatable factors linked to TIAs and stroke are high blood pressure, cigarette smoking, heart disease, carotid artery disease, diabetes, and heavy use of alcohol. Medical help is available to reduce and eliminate these factors. Lifestyle changes such as eating a balanced diet, maintaining healthy weight, exercising, and enrolling in smoking and alcohol cessation programs can also reduce these factors.


NINDS is the leading supporter of research on stroke and TIA in the U.S. and sponsors studies ranging from clinical trials to investigations of basic biological mechanisms as well as studies with animals.


Porencephaly is an extremely rare disorder of the central nervous system in which a cyst or cavity filled with cerebrospinal fluid develops in the brain. It is usually the result of damage from stroke or infection after birth (the more common type), but it can also be caused by abnormal development before birth (which is inherited and less common). Diagnosis is usually made before an infant reaches his or her first birthday. Symptoms of porencephaly include delayed growth and development, spastic hemiplegia (slight or incomplete paralysis), hypotonia (low muscle tone), seizures (often infantile spasms), and macrocephaly (large head) or microcephaly (small head). Children with porencephaly may have poor or absent speech development, epilepsy, hydrocephalus (accumulation of fluid in the brain), spastic contractures (shrinkage or shortening of the muscles), and cognitive impairment.


Treatment may include physical therapy, medication for seizures, and the placement of a shunt in the brain to remove excess fluid in the brain.


The prognosis for children with porencephaly varies according to the location and extent of the cysts or cavities. Some children with this disorder develop only minor neurological problems and have normal intelligence, while others may be severely disabled and die before their second decade of life.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to porencephaly in laboratories at the NIH and also support additional research through grants to major medical institutions across the country. Much of this research explores the complex mechanisms of normal brain development. The knowledge gained from these fundamental studies will provide a foundation for developing ways to prevent porecephaly and the other cephalic disorders.


Machado-Joseph disease (MJD), which is also called spinocerebellar ataxia type 3, is a rare hereditary ataxia (ataxia is a medical term meaning lack of muscle control). The disease is characterized by slowly progressive clumsiness and weakness in the arms and legs, spasticity, a staggering lurching gait easily mistaken for drunkenness, difficulty with speech and swallowing, involuntary eye movements, double vision, and frequent urination. Some individuals also have dystonia (sustained muscle contractions that cause twisting of the body and limbs, repetitive movements, abnormal postures, and rigidity) or symptoms similar to those of Parkinson's disease. Others have twitching of the face or tongue, or peculiar bulging eyes. Almost all individuals with MJD experience vision problems, including double vision or blurred vision, loss of the ability to distinguish color and/or contrast, and inability to control eye movements.


MJD is incurable, but some symptoms of the disease can be treated. For those individuals who show parkinsonian features, levodopa therapy can help for many years. Treatment with antispasmodic drugs, such as baclofen, can help reduce spasticity. Botulinum toxin can also treat severe spasticity as well as some symptoms of dystonia. Speech problems and trouble swallowing can be treated with medication and speech therapy. Physiotherapy can help patients cope with disability associated with gait problems. Physical aids, such as walkers and wheelchairs, can assist with everyday activities.


The severity of the disease is related to the age of onset, with earlier onset associated with more severe forms of the disease. Symptoms can begin any time between early adolescence and about 70 years of age. MJD is a progressive disease, meaning that symptoms get worse with time. Life expectancy ranges from the mid-thirties for those with severe forms of MJD to a normal life expectancy for those with mild forms. The cause of death for those who die early is often aspiration pneumonia.


The National Institute of Neurological Disorders and Stroke (NINDS) conducts MJD research in its laboratories at the National Institutes of Health (NIH) and also supports MJD research through grants to major medical institutions across the country. Ongoing research includes studies to better understand the genetic, molecular, and cellular mechanisms that underlie inherited neurodegenerative diseases such as MJD. Other research areas include the development of novel therapies to treat the symptoms of MJD, efforts to identify diagnostic markers and to improve current diagnostic procedures for the disease, and population studies to identify affected families.


Sleep apnea is a common sleep disorder characterized by brief interruptions of breathing during sleep. These episodes usually last 10 seconds or more and occur repeatedly throughout the night. People with sleep apnea will partially awaken as they struggle to breathe, but in the morning they will not be aware of the disturbances in their sleep. The most common type of sleep apnea is obstructive sleep apnea (OSA), caused by relaxation of soft tissue in the back of the throat that blocks the passage of air. Central sleep apnea (CSA) is caused by irregularities in the brains normal signals to breathe. Most people with sleep apnea will have a combination of both types. The hallmark symptom of the disorder is excessive daytime sleepiness. Additional symptoms of sleep apnea include restless sleep, loud snoring (with periods of silence followed by gasps), falling asleep during the day, morning headaches, trouble concentrating, irritability, forgetfulness, mood or behavior changes, anxiety, and depression. Not everyone who has these symptoms will have sleep apnea, but it is recommended that people who are experiencing even a few of these symptoms visit their doctor for evaluation. Sleep apnea is more likely to occur in men than women, and in people who are overweight or obese.


There are a variety of treatments for sleep apnea, depending on an individuals medical history and the severity of the disorder. Most treatment regimens begin with lifestyle changes, such as avoiding alcohol and medications that relax the central nervous system (for example, sedatives and muscle relaxants), losing weight, and quitting smoking. Some people are helped by special pillows or devices that keep them from sleeping on their backs, or oral appliances to keep the airway open during sleep. If these conservative methods are inadequate, doctors often recommend continuous positive airway pressure (CPAP), in which a face mask is attached to a tube and a machine that blows pressurized air into the mask and through the airway to keep it open. Also available are machines that offer variable positive airway pressure (VPAP) and automatic positive airway pressure (APAP). There are also surgical procedures that can be used to remove tissue and widen the airway. Some individuals may need a combination of therapies to successfully treat their sleep apnea.


Untreated, sleep apnea can be life threatening. Excessive daytime sleepiness can cause people to fall asleep at inappropriate times, such as while driving. Sleep apnea also appears to put individuals at risk for stroke and transient ischemic attacks (TIAs, also known as mini-strokes), and is associated with coronary heart disease, heart failure, irregular heartbeat, heart attack, and high blood pressure. Although there is no cure for sleep apnea, recent studies show that successful treatment can reduce the risk of heart and blood pressure problems.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to sleep apnea in laboratories at the NIH, and also support additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure sleep disorders, such as sleep apnea.


Central pontine myelinolysis (CPM) is a neurological disorder that most frequently occurs after too rapid medical correction of sodium deficiency (hyponatremia). The rapid rise in sodium concentration is accompanied by the movement of small molecules and pulls water from brain cells. Through a mechanism that is only partly understood, the shift in water and brain molecules leads to the destruction of myelin, a substance that surrounds and protects nerve fibers. Nerve cells (neurons) can also be damaged. Certain areas of the brain are particularly susceptible to myelinolysis, especially the part of the brain stem called the pons. Some individuals will also have damage in other areas of the brain, which is called extrapontine myelinolysis (EPM). Experts estimate that 10 percent of those with CPM will also have areas of EPM.

The initial symptoms of myelinolysis, which begin to appear 2 to 3 days after hyponatremia is corrected, include a depressed level of awareness, difficulty speaking (dysarthria or mutism), and difficulty swallowing (dysphagia). Additional symptoms often arise over the next 1-2 weeks, including impaired thinking, weakness or paralysis in the arms and legs, stiffness, impaired sensation, and difficulty with coordination. At its most severe, myelinolysis can lead to coma, locked-in syndrome (which is the complete paralysis of all of the voluntary muscles in the body except for those that control the eyes), and death.

Although many affected people improve over weeks to months, some have permanent disability. Some also develop new symptoms later, including behavioral or intellectual impairment or movement disorders like parkinsonism or tremor.

Anyone, including adults and children, who undergoes a rapid rise in serum sodium is at risk for myelinolysis. Some individuals who are particularly vulnerable are those with chronic alcoholism and those who have had a liver transplant. Myelinolysis has occurred in individuals undergoing renal dialysis, burn victims, people with HIV-AIDS, people over-using water loss pills (diuretics), and women with eating disorders such as anorexia or bulimia. The risk for CPM is greater if the serum (blood) sodium was low for at least 2 days before correction.


The ideal treatment for myelinolysis is to prevent the disorder by identifying individuals at risk and following careful guidelines for evaluation and correction of hyponatremia. These guidelines aim to safely restore the serum sodium level, while protecting the brain. For those who have hyponatremia for at least 2 days, or for whom the duration is not known, the rate of rise in the serum sodium concentration should be kept below 10 mmol/L during any 24-hour period, if possible.

For those who develop myelinolysis, treatment is supportive. Some physicians have tried to treat myelinolysis with steroid medication or other experimental therapies, but none has been proven effective. Individuals are likely to require extensive and prolonged physical therapy and rehabilitation. Those individuals who develop parkinsonian symptoms may respond to the dopaminergic drugs that work for individuals with Parkinsons disease.


The prognosis for myelinolysis varies. Some individuals die and others recover completely. Although the disorder was originally considered to have a mortality rate of 50 percent or more, improved imaging techniques and early diagnosis have led to a better prognosis for many people. Most individuals improve gradually, but still continue to have challenges with speech, walking, emotional ups and downs, and forgetfulness.


The mission of the National Institute of Neurological Disorders and Stroke (NINDS) is to seek fundamental knowledge of the brain and nervous system and to use that knowledge to reduce the burden of neurological disease. The NINDS is a component of the National Institutes of Health, the leading supporter of biomedical research in the world.

The NINDS conducts and supports research to better understand conditions that affect the protective myelin coating around nerve fibers and ways to prevent and treat the destruction of myelin. Scientists hope to develop drugs that can prevent brain cells from dying or help them produce new myelin. Research funded by the NIH's National Institute of Diabetes and Digestive and Kidney Diseases aims to understand the biological mechanisms involved in water balance in the body.


von Hippel-Lindau disease (VHL) is a rare, genetic multi-system disorder in which non-cancerous tumors grow in certain parts of the body. Slow-growing hemgioblastomas -- benign tumors with many blood vessels -- may develop in the brain, spinal cord, the retinas of the eyes, and near the inner ear. Cysts (fluid-filled sacs) may develop around the hemangioblastomas. Other types of tumors develop in the adrenal glands, the kidneys, or the pancreas. Symptoms of VHL vary among individuals and depend on the size and location of the tumors. Symptoms may include headaches, problems with balance and walking, dizziness, weakness of the limbs, vision problems, deafness in one ear, and high blood pressure. Individuals with VHL are also at a higher risk than normal for certain types of cancer, especially kidney cancer.


Treatment for VHL varies according to the location and size of the tumor. In general, the objective of treatment is to treat the tumors before they grow to a size large enough to cause permanent problems by putting pressure on the brain or spinal cord. this pressure can block the flow of cerebrospinal fluid in the nervous system, impair vision, or create deafness. Treatment of most cases of VHL usually involves surgery to remove the tumors before they become harmful. Certain tumors can be treated with focused high-dose irradiation. Individuals with VHL need careful monitoring by a physician and/or medical team familiar with the disorder.


The prognosis for individuals with VHL depends on then number, location, and complications of the tumors. Untreated, VHL may result in blindness and/or permanent brain damage. With early detection and treatment the prognosis is significantly improved. Death is usually caused by complications of brain tumors or kidney cancer.


The mission of the National Institute of Neurological Disorders and Stroke (NINDS) is to seek fundamental knowledge about the brain and nervous system, and to use that knowledge to reduce the burden of neurological disease. The NINDS pursues a vigorous program of research aimed at preventing and treating disorders that cause tumors in the brain and spinal cord such as VHL. A natural history study hopes to learn more about the growth of brain and spinal cord tumors, as well as cysts that develop in association with them in individuals with VHL. Researchers will examine how fast the tumors grow and try to determine which factors (such as puberty, pregnancy, menopause, or blood proteins) affect tumor growth. Based on laboratory findings, NINDS researchers are planning drug trials for individuals with VHL. For example, NNDS scientists hope to learn if a drug that fights other cancers might slow the growth of hemangioblastomas in some people with VHL. The NIH's National Cancer Institute conducts research aimed at treating kidney tumors in individuals with VHL, as well as studies to identify gene mutations in people who are at risk of developing the disease..


Infantile neuroaxonal dystrophy (INAD) is a rare inherited neurological disorder. It affects axons, the part of a nerve cell that carries messages from the brain to other parts of the body, and causes progressive loss of vision, muscular control, and mental skills. While the basic genetic and metabolic causes are unknown, INAD is the result of an abnormal build-up of toxic substances in nerves that communicate with muscles, skin, and the conjunctive tissue around the eyes. Symptoms usually begin within the first 2 years of life, with the loss of head control and the ability to sit, crawl, or walk, accompanied by deterioration in vision and speech. Some children may have seizures. Distinctive facial deformities may be present at birth, including a prominent forehead, crossed eyes, an unusually small nose or jaw, and large, low-set ears. INAD is an autosomal recessive disorder, which means that both parents must be carriers of the defective gene that causes INAD to pass it on to their child. Electrophysiology (nerve conduction velocities) may be helpful for diagnosis, although diagnosis is usually confirmed by tissue biopsy of skin, rectum, nerve or conjunctive tissue to confirm the presence of characteristic swellings (spheroid bodies) in the nerve axons.


There is no cure for INAD and no treatment that can stop the progress of the disease. Treatment is symptomatic and supportive. Doctors can prescribe medications for pain relief and sedation. Physiotherapists and other physical therapists can teach parents and caregivers how to position and seat their child, and to exercise arms and legs to maintain comfort.


INAD is a progressive disease. Once symptoms begin, they will worsen over time. Generally, a babys development starts to slow down between the ages of 6 months to 3 years. The first symptoms may be slowing of motor and mental development, followed by loss or regression of previously acquired skills. Rapid, wobbly eye movements and squints may be the first symptoms, followed by floppiness in the body and legs (more than in the arms). For the first few years, a baby with INAD will be alert and responsive, despite being increasingly physically impaired. Eventually, because of deterioration in vision, speech, and mental skills, the child will lose touch with its surroundings. Death usually occurs between the ages of 5 to 10 years.


Researchers continue to search for the defective gene that causes INAD in hopes of developing drugs that can stop the disease. The National Institute of Neurological Disorders and Stroke (NINDS) conducts research related to INAD in its laboratories at the National Institutes of Health (NIH), and also supports additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure disorders such as INAD.


Chiari malformations (CMs) are structural defects in the cerebellum, the part of the brain that controls balance. When the indented bony space at the lower rear of the skull is smaller than normal, the cerebellum and brain stem can be pushed downward. The resulting pressure on the cerebellum can block the flow of cerebrospinal fluid (the liquid that surrounds and protects the brain and spinal cord) and can cause a range of symptoms including dizziness, muscle weakness, numbness, vision problems, headache, and problems with balance and coordination. Symptoms may change for some individuals depending on buildup of CNS and any resulting pressure on tissue and nerves. CMs are classified by the severity of the disorder and the parts of the brain that protrude into the spinal canal. The most common is Type I, which may not cause symptoms and is often found by accident during an examination for another condition. Type II (also called Arnold-Chiari malformation) is usually accompanied by a myelomeningocele-a form of spina bifida that occurs when the spinal canal and backbone do not close before birth, causing the spinal cord to protrude through an opening in the back. This can cause partial or complete paralysis below the spinal opening. Type III is the most serious form of CM, and causes severe neurological defects. Other conditions sometimes associated with CM include hydrocephalus, syringomyelia (a fluid-filled cyst in the spinal cord), and spinal curvature.


Medications may ease certain symptoms, such as pain. Surgery is the only treatment available to correct functional disturbances or halt the progression of damage to the central nervous system. More than one surgery may be needed to treat the condition. Some CMs have no noticeable symptoms and do not interfere with the person's activities of daily living.


Many people with Type I CM are asymptomatic and do not know they have the condition. Many individuals with the more severe types of CM and have surgery see a reduction in their symptoms and/or prolonged periods of relative stability, although paralysis is generally permanent.


The NINDS supports research on disorders of the brain and nervous system such as Chiari malformations. The goals of this research are to increase scientific understanding of these disorders and to find ways to prevent, treat, and, ultimately, cure them. Current NINDS-funded research includes studies to better understand the genetic factors responsible for the malformation, and factors that influence the development, progression, and relief of symptoms among people with syringomyelia, including those with Chiari I malformations.


Neurotoxicity occurs when the exposure to natural or manmade toxic substances (neurotoxicants) alters the normal activity of the nervous system. This can eventually disrupt or even kill neurons, key cells that transmit and process signals in the brain and other parts of the nervous system. Neurotoxicity can result from exposure to substances used in chemotherapy, radiation treatment, drug therapies, and organ transplants, as well as exposure to heavy metals such as lead and mercury, certain foods and food additives, pesticides, industrial and/or cleaning solvents, cosmetics, and some naturally occurring substances. Symptoms may appear immediately after exposure or be delayed. They may include limb weakness or numbness; loss of memory, vision, and/or intellect; headache; cognitive and behavioral problems; and sexual dysfunction. Individuals with certain disorders may be especially vulnerable to neurotoxicants.


Treatment involves eliminating or reducing exposure to the toxic substance, followed by symptomatic and supportive therapy.


The prognosis depends upon the length and degree of exposure and the severity of neurological injury. In some instances, exposure to neurotoxicants can be fatal. In others, patients may survive but not fully recover. In other situations, many individuals recover completely after treatment.


The NINDS supports research on disorders of the brain and nervous system such as neurotoxicity, aimed at learning more about these disorders and finding ways to prevent and treat them. Scientists are investigating the role occupational or environmental toxicants have on progressive neurodegenerative disorders such as Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, and dementia. Also being studied are the mechanisms that trigger neuroimmune responses in the central nervous system and the possibility that some brain disorders in children may occur when environmental triggers interact with genes.


All forms of myasthenia are due to problems in the communication between nerve cells and muscles. Most involve the activities of neurotransmitters. Neurotransmitters are chemicals that allow neurons to relay information from one cell to the next. For neurotransmitters to be effective, the nerve cell must release the neurotransmitter properly, and the muscle cell must be able to detect the neurotransmitter and respond to its signal properly.

The most common type of myasthenia, myasthenia gravis, is caused by an abnormal immune response in which antibodies block the ability of the muscle to detect the neurotransmitter. Congenital myasthenia, however, differs from myasthenia gravis because the disrupted communication isn't caused by antibodies, but by genetic defects.

There are several different subtypes of congenital myasthenia, each the result of a specific genetic mutation. Since all types of myasthenia are due to the inability of nerves to trigger muscle activity, they all involve weakness, although there is some variability in the specific muscles affected.

Symptoms of congenital myasthenia usually appear in the first few years of childhood, but may not be noticeable until much later, occasionally remaining unrecognized until adulthood. If the symptoms begin in infancy, they usually appear as "floppiness" and a failure to meet developmental milestones, such as rolling over or sitting up. Some infants may also have episodes of choking or pauses in breathing. If the symptoms begin in toddlers or preschool children, they appear as weakness during physical activities or an inability to perform age-appropriate actions, such as running or climbing. In addition, if eye muscles are involved, children may have droopy eyelids, "lazy eye," or double vision. If mouth or throat muscles are involved, children may have difficulty speaking or swallowing. An important characteristic of myasthenia is that the weakness worsens during continuous activity, with strength returning, at least partially, after resting.

Congenital myasthenia is an inherited (genetic) disorder. All but one known subtype are recessive disorders, which means that a child will have to have two copies of the abnormal gene (one from each parent) in order to develop the disease. To diagnose congenital myasthenia, a neurologist will test various muscles to determine if they grow weaker with repeated activity. The doctor will also test the electrical activity of nerves and muscles using electromyography (EMG) and nerve conduction tests (NCS). Blood tests are often used to determine if antibodies could be causing the symptoms. Genetic tests may be ordered.


The possibilities for treatment depend on the specific subtype of congenital myasthenia. Most treatments attempt to improve the signaling between nerve cell and muscle. These drugs include pyridostigmine, fluoxetine, ephedrine, and 3,4-diaminopyridine. Treatments to alter the immune system are not used for this form of myasthenia. There are no treatments to cure the underlying genetic abnormality.


The prognosis depends on the specific subtype of congenital myasthenia, the muscles involved, and the age at onset of symptoms. If a child has difficulty breathing, feeding, or swallowing, they may be vulnerable to pneumonia or respiratory failure. In other cases, weakness is stable and does not worsen over time. In one subtype, weakness improves with time. Life-span is normal in most cases in which respiratory function is not compromised.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) support research related to congenital myasthenia through grants to major research institutions across the country. Much of this research focuses on finding better ways to prevent, treat and ultimately cure disorders such as congenital myasthenia.


Attention deficit-hyperactivity disorder (ADHD) is a neurobehavioral disorder that affects 3-5 percent of all American children. It interferes with a person's ability to stay on a task and to exercise age-appropriate inhibition (cognitive alone or both cognitive and behavioral). Some of the warning signs of ADHD include failure to listen to instructions, inability to organize oneself and school work, fidgeting with hands and feet, talking too much, leaving projects, chores and homework unfinished, and having trouble paying attention to and responding to details. There are several types of ADHD: a predominantly inattentive subtype, a predominantly hyperactive-impulsive subtype, and a combined subtype. ADHD is usually diagnosed in childhood, although the condition can continue into the adult years.


The usual course of treatment may include medications such as methylphenidate (Ritalin) or dextroamphetamine (Dexedrine), which are stimulants that decrease impulsivity and hyperactivity and increase attention. Most experts agree that treatment for ADHD should address multiple aspects of the individual's functioning and should not be limited to the use of medications alone. Treatment should include structured classroom management, parent education (to address discipline and limit-setting), and tutoring and/or behavioral therapy for the child.


There is no "cure" for ADHD. Children with the disorder seldom outgrow it; however, some may find adaptive ways to accommodate the ADHD as they mature.


Several components of the NIH support research on developmental disorders such as ADHD. Research programs of the NINDS, the National Institute of Mental Health (NIMH), and the National Institute of Child Health and Human Development (NICHD) seek to address unanswered questions about the causes of ADHD, as well as to improve diagnosis and treatment.


Tremor is an unintentional, somewhat rhythmic, muscle movement involving to-and-fro movements (oscillations) of one or more parts of the body. Essential tremor (previously called benign essential tremor) is the most common form of abnormal tremor. (In some people, tremor is a symptom of a neurological disorder or appears as a side effect of certain drugs.) Although it may be mild and nonprogressive in some people, in others the tremor is slowly progressive, starting on one side of the body but eventually affecting both sides. Hand tremor is most common but the head, arms, voice, tongue, legs, and trunk may also be involved. Hand tremor may cause problems with purposeful movements such as eating, writing, sewing, or shaving. Head tremor may be seen as a "yes-yes" or "no-no" motion. Essential tremor may be accompanied by mild gait disturbance. Heightened emotion, stress, fever, physical exhaustion, or low blood sugar may trigger tremors or increase their severity. There may be mild degeneration in the certain parts of the cerebellum in persons with essential tremor. Onset is most common after age 40, although symptoms can appear at any age. Children of a parent who has essential tremor have up to a 50 percent chance of inheriting the condition. Essential tremor is not associated with any known pathology.


There is no definitive cure for essential tremor. Symptomatic drug therapy may include propranolol or other beta blockers and primidone, an anticonvulsant drug. Eliminating tremor "triggers" such as caffeine and other stimulants from the diet is often recommended. Physical and occupational therapy may help to reduce tremor and improve coordination and muscle control for some individuals. Deep brain stimulation uses a surgically implanted, battery-operated medical device called a neurostimulator to delivery electrical stimulation to targeted areas of the brain that control movement, temporarily blocking the nerve signals that cause tremor. Other surgical intervention is effective but may have side effects.


Although essential tremor is not life-threatening, it can make it harder to perform daily tasks and is embarrassing to some people. Tremor frequency may decrease as the person ages, but the severity may increase, affecting the person's ability to perform certain tasks or activities of daily living. In many people the tremor may be mild throughout life.


The National Institute of Neurological Disorders and Stroke, a unit of the National Institutes of Health (NIH) within the U.S. Department of Health and Human Services, is the nation's leading federal funder of research on disorders of the brain and nervous system. The NINDS sponsors research on tremor both at its facilities at the NIH and through grants to medical centers.

Scientists at the NINDS are evaluating the effectiveness of 1-octanol, a substance similar to alcohol but less intoxicating, for treating essential tremor. Results of two previous NIH studies have shown this agent to be promising as a potential new treatment.

Scientists are also studying the effectiveness of botulinum toxin as a treatment for a variety of involuntary movement disorders, including essential tremor of the hand.


The epilepsies are a spectrum of brain disorders ranging from severe, life-threatening and disabling, to ones that are much more benign. In epilepsy, the normal pattern of neuronal activity becomes disturbed, causing strange sensations, emotions, and behavior or sometimes convulsions, muscle spasms, and loss of consciousness. The epilepsies have many possible causes and there are several types of seizures. Anything that disturbs the normal pattern of neuron activityfrom illness to brain damage to abnormal brain developmentcan lead to seizures. Epilepsy may develop because of an abnormality in brain wiring, an imbalance of nerve signaling chemicals called neurotransmitters, changes in important features of brain cells called channels, or some combination of these and other factors. Having a single seizure as the result of a high fever (called febrile seizure) or head injury does not necessarily mean that a person has epilepsy. Only when a person has had two or more seizures is he or she considered to have epilepsy. A measurement of electrical activity in the brain and brain scans such as magnetic resonance imaging or computed tomography are common diagnostic tests for epilepsy.


Once epilepsy is diagnosed, it is important to begin treatment as soon as possible. For about 70 percent of those diagnosed with epilepsy, seizures can be controlled with modern medicines and surgical techniques. Some drugs are more effective for specific types of seizures. An individual with seizures, particularly those that are not easily controlled, may want to see a neurologist specifically trained to treat epilepsy. In some children, special diets may help to control seizures when medications are either not effective or cause serious side effects.


While epilepsy cannot be cured, for some people the seizures can be controlled with medication, diet, devices, and/or surgery. Most seizures do not cause brain damage, but ongoing uncontrolled seizures may cause brain damage. It is not uncommon for people with epilepsy, especially children, to develop behavioral and emotional problems in conjunction with seizures. Issues may also arise as a result of the stigma attached to having epilepsy, which can led to embarrassment and frustration or bullying, teasing, or avoidance in school and other social settings. For many people with epilepsy, the risk of seizures restricts their independence (some states refuse drivers licenses to people with epilepsy) and recreational activities.

Epilepsy can be a life-threatening condition. Some people with epilepsy are at special risk for abnormally prolonged seizures or sudden unexplained death in epilepsy.


Scientists are studying the underlying causes of the epilepsies in children, adults, and the elderly, as well as seizures that occur following brain trauma, stroke, and brain tumors. Ongoing research is focused on developing new model systems that can be used to more quickly screen potential new treatments for the epilepsies. The identification of genes or other genetic information that may influence or cause the epilepsies may allow doctors to prevent the disorders or to predict which treatments will be most beneficial to individuals with specific types of epilepsy. Scientists also continue to study how neurotransmitters interact with brain cells to control nerve firing and how non-neuronal cells in the brain contribute to seizures. Researchers funded by the National Institutes of Health have developed a flexible brain implant that could one day be used to treat seizures. Scientists are continually improving MRI and other brain scans that may assist in diagnosing the epilepsies and identify the source, or focus, of the seizures in the brain. Other areas of study include prevention of seizures and the role of inflammation in epilepsy. Patients may enter trials of experimental drugs and surgical interventions.

More about epilepsy research


Zellweger syndrome is one of a group of four related diseases called peroxisome biogenesis disorders (PBD). The diseases are caused by defects in any one of 13 genes, termed PEX genes, required for the normal formation and function of peroxisomes. The PBDs are divided into two groups: Zellweger spectrum disorders and Rhizomelic Chondrodysplasia Punctua spectrum. The Zellweger spectrum is comprised of three disorders that have considerable overlap of features. These include Zellweger syndrome (ZS, the most severe form), neonatal adrenoleukodystrophy (NALD), and Infantile Refsum disease (IRD, the least severe form).

Peroxisomes are cell structures that break down toxic substances and synthesize lipids (fatty acids. oils, and waxes) that are necessary for cell function. Peroxisomes are required for normal brain development and function and the formation of myelin, the whitish substance that coats nerve fibers. They are also required for normal eye, liver, kidney, and bone functions. Zellweger spectrum disorders result from dysfunctional lipid metabolism, including the over-accumulation of very long-chain fatty acids and phytanic acid, and defects of bile acids and plasmalogens--specialized lipids found in cell membranes and myelin sheaths of nerve fibers. Symptoms of these disorders include an enlarged liver; characteristic facial features such as a high forehead, underdeveloped eyebrow ridges, and wide-set eyes; and neurological abnormalities such as cognitive impairment and seizures. Infants will Zellweger syndrome also lack muscle tone, sometimes to the point of being unable to move, and may not be able to suck or swallow. Some babies will be born with glaucoma, retinal degeneration, and impaired hearing. Jaundice and gastrointestinal bleeding also may occur.


There is no cure for Zellweger syndrome, nor is there a standard course of treatment. Since the metabolic and neurological abnormalities that cause the symptoms of Zellweger syndrome are caused during fetal development, treatments to correct these abnormalities after birth are limited. Most treatments are symptomatic and supportive.


The prognosis for infants with Zellweger syndrome is poor. Most infants do not survive past the first 6 months, and usually succumb to respiratory distress, gastrointestinal bleeding, or liver failure.


The National Institute of Neurological Disorders and Stroke (NINDS), and other institutes of the National Institutes of Health (NIH), conduct research exploring the molecular and genetic basis of Zellweger syndrome and the other PBDs, and also support additional research through grants to major research institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure disorders such as Zellweger syndrome.


A coma, sometimes also called persistent vegetative state, is a profound or deep state of unconsciousness. Persistent vegetative state is not brain-death. An individual in a state of coma is alive but unable to move or respond to his or her environment. Coma may occur as a complication of an underlying illness, or as a result of injuries, such as head trauma. . Individuals in such a state have lost their thinking abilities and awareness of their surroundings, but retain non-cognitive function and normal sleep patterns. Even though those in a persistent vegetative state lose their higher brain functions, other key functions such as breathing and circulation remain relatively intact. Spontaneous movements may occur, and the eyes may open in response to external stimuli. Individuals may even occasionally grimace, cry, or laugh. Although individuals in a persistent vegetative state may appear somewhat normal, they do not speak and they are unable to respond to commands.


Once an individual is out of immediate danger, the medical care team focuses on preventing infections and maintaining a healthy physical state. This will often include preventing pneumonia and bedsores and providing balanced nutrition. Physical therapy may also be used to prevent contractures (permanent muscular contractions) and deformities of the bones, joints, and muscles that would limit recovery for those who emerge from coma.


The outcome for coma and persistent vegetative state depends on the cause, severity, and site of neurological damage. Individuals may emerge from coma with a combination of physical, intellectual, and psychological difficulties that need special attention. Recovery usually occurs gradually, with some acquiring more and more ability to respond. Some individuals never progress beyond very basic responses, but many recover full awareness. Individuals recovering from coma require close medical supervision. A coma rarely lasts more than 2 to 4 weeks. Some patients may regain a degree of awareness after persistent vegetative state. Others may remain in that state for years or even decades. The most common cause of death for someone in a persistent vegetative state is infection, such as pneumonia.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to coma in their laboratories at the NIH and also support additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent and treat coma.


Acute disseminated encephalomyelitis (ADEM) is characterized by a brief but widespread attack of inflammation in the brain and spinal cord that damages myelin  the protective covering of nerve fibers. ADEM often follows viral or bacterial infections, or less often, vaccination for measles, mumps, or rubella. The symptoms of ADEM appear rapidly, beginning with encephalitis-like symptoms such as fever, fatigue, headache, nausea and vomiting, and in the most severe cases, seizures and coma. ADEM typically damages white matter (brain tissue that takes its name from the white color of myelin), leading to neurological symptoms such as visual loss (due to inflammation of the optic nerve)in one or both eyes, weakness even to the point of paralysis, and difficulty coordinating voluntary muscle movements (such as those used in walking). ADEM is sometimes misdiagnosed as a severe first attack of multiple sclerosis (MS), since the symptoms and the appearance of the white matter injury on brain imaging may be similar. However, ADEM has several features which differentiate it from MS. First, unlike MS patients, persons with ADEM will have rapid onset of fever, a history of recent infection or immunization, and some degree of impairment of consciousness, perhaps even coma; these features are not typically seen in MS. Children are more likely than adults to have ADEM, whereas MS is a rare diagnosis in children. In addition, ADEM usually consists of a single episode or attack of widespread myelin damage, while MS features many attacks over the course of time. Doctors will often use imaging techniques, such as MRI (magnetic resonance imaging), to search for old and new lesions (areas of damage) on the brain. The presence of older brain lesions on MRI suggest that the condition may be MS rather than ADEM, since MS can cause brain lesions before symptoms become obvious. In rare situations, a brain biopsy may be necessary to differentiate between ADEM and some other diseases that involve inflammation and damage to myelin..


Treatment for ADEM is targeted at suppressing inflammation in the brain using anti-inflammatory drugs. Most individuals respond to several days of intravenous corticosteroids such as methylprednisolone, followed by oral corticosteroid treatment. When corticosteroids fail to work, plasmapheresis or intravenous immunoglobulin therapy are possible secondary treatment options that are reported to help in some severe cases. Additional treatment is symptomatic and supportive.


Corticosteroid therapy typically helps hasten recovery from most ADEM symptoms. The long-term prognosis for individuals with ADEM is generally favorable. For most individuals, recovery begins within days, and within six months the majority of ADEM patients will have total or near total recoveries. Others may have mild to moderate lifelong impairment ranging from cognitive difficulties, weakness, loss of vision, or numbness. Severe cases of ADEM can be fatal but this is a very rare occurrence. ADEM can recur, usually within months of the initial diagnosis, and is treated by restarting corticosteroids. A small fraction of individuals who are initially diagnosed as having ADEM can go on to develop MS, but there is currently no method or known risk factors to predict whom those individuals will be.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to ADEM in laboratories at the NIH, and also support additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure demyelinating disorders such as ADEM.


Myotonia is a medical term that refers to a neuromuscular condition in which the relaxation of a muscle is impaired. It can affect any muscle group. Repeated effort will be needed to relax the muscle, although the condition usually improves after the muscles have warmed-up. Individuals with myotonia may have trouble releasing their grip on objects or may have difficulty rising from a seated position. They may walk with a stiff, awkward gait. Myotonia is caused by an abnormality in the muscle membrane, and is often associated with inherited neurological disorders. Myotonia is commonly seen in individuals with myotonic muscular dystrophy, myotonia congenita, and in people who have one of a group of neurological disorders called the channelopathies, which are inherited diseases that are caused by mutations in the chloride sodium or potassium channels that regulate the muscle membrane. Myotonia may also be triggered by exposure to cold.


Treatment for myotonia may include mexiletine, quinine, phenytoin, and other anticonvulsant drugs. Physical therapy and other rehabilitative measures may help muscle function.


Myotonia is a chronic disorder. Symptoms may improve later in life.


The National Institute of Neurological Disorders and Stroke supports and conducts an extensive research program on neuromuscular disorders. The goals of this research are to learn more about these disorders and to find ways to treat, prevent, and cure them.


Creutzfeldt-Jakob disease (CJD) is a rare, degenerative,fatal brain disorder. Typically, onset of symptoms occurs at about age 60. There are three major categories of CJD: sporadic (the most common form, in which people do not have any risk factors for the disease); hereditary (in which the person has a family member with the disease and tests positive for a genetic mutation), and acquired (in which the disease is transmitted by exposure to brain and nervous system tissue, usually through certain medical procedures. A form called variant CJD can be acquired by eating meat from cattle affected by a disease similar to CJD, called bovine spongiform encephalopathy (commonly called mad cow disease). Symptoms of CJD include problems with muscular coordination, personality changes including progressive and severe mental impairment, impaired vision that may lead to blindness, and involuntary muscle jerks called myoclonus. People eventually lose the ability to move and speak and enter a coma. Tests that help in the diagnosis of CJD include electroencephalography (which measures brain waves), detection of certain proteins in the fluid that surrounds the brain and spinal cord, and magnetic resonance imaging.. The first concern is to rule out treatable forms of dementia such as encephalitis or chronic meningitis. The only way to confirm a diagnosis of CJD is by brain biopsy or autopsy. In a brain biopsy, a neurosurgeon removes a small piece of tissue from the person's brain so that it can be examined by a neurologist. Because a correct diagnosis of CJD does not help the individual, a brain biopsy is discouraged unless it is need to rule out a treatable disorder. .


There is no treatment that can cure or control CJD, although studies of a variety of drugs are now in progress. Current treatment is aimed at alleviating symptoms and making the person as comfortable as possible. Opiate drugs can help relieve pain, and the drugs clonazepam and sodium valproate may help relieve involuntary muscle jerks.Intravenous fluids and artificial feeding may be needed in later stages of the disease.


About 70 percent of individuals die within one year. In the early stages of disease, people may have failing memory, behavioral changes, lack of coordination and visual disturbances. As the illness progresses, mental deterioration becomes pronounced and involuntary movements, blindness, weakness of extremities, and coma may occur.


The mission of the National Institute of Neurological Disorders and Stroke (NINDS) is to seek fundamental knowledge about the brain and nervous system, and to use that knowledge to reduce the burden of neurological disease. The leading scientific theory at this time maintains that CJD is caused by a type of protein called a prion. The harmless and the infectious forms of the prion protein are nearly identical, but the infectious form takes a different folded shape than the normal protein. Researchers are trying to discover factors that influence prion infectivity and how the disorder damages the brain. Using rodent models of the disease and brain tissue from autopsies, researchers are also trying to develop improved diagnostic tests for CJD and to learn what changes ultimately kill the neurons so that effective treatments can be developed.


Chorea is an abnormal involuntary movement disorder, one of a group of neurological disorders called dyskinesias, which are caused by overactivity of the neurotransmitter dopamine in the areas of the brain that control movement. Chorea is characterized by brief, irregular contractions that are not repetitive or rhythmic, but appear to flow from one muscle to the next. Chorea often occurs with athetosis, which adds twisting and writhing movements. Chorea is a primary feature of Huntington's disease, a progressive, hereditary movement disorder that appears in adults, but it may also occur in a variety of other conditions. Syndenham's chorea occurs in a small percentage (20 percent) of children and adolescents as a complication of rheumatic fever. Chorea can also be induced by drugs (levodopa, anti-convulsants, and anti-psychotics) metabolic and endocrine disorders, and vascular incidents.


There is no standard course of treatment for chorea. Treatment depends on the type of chorea and the associated disease. Treatment for Huntington's disease is supportive, while treatment for Syndenham's chorea usually involves antibiotic drugs to treat the infection, followed by drug therapy to prevent recurrence. Adjusting medication dosages can treat drug-induced chorea. Metabolic and endocrine-related choreas are treated according to the cause(s) of symptoms.


The prognosis for individuals with chorea varies depending on the type of chorea and the associated disease. Huntington's disease is a progressive, and ultimately, fatal disease. Syndenham's chorea is treatable and curable.


The NINDS supports research on movement disorders such as chorea. The goals of this research are to increase understanding of these disorders and to find ways to prevent and treat them.


Ohtahara syndrome is a neurological disorder characterized by seizures. The disorder affects newborns, usually within the first three months of life (most often within the first 10 days) in the form of epileptic seizures. Infants have primarily tonic seizures, but may also experience partial seizures, and rarely, myoclonic seizures. Ohtahara syndrome is most commonly caused by metabolic disorders or structural damage in the brain, although the cause or causes for many cases cant be determined. Most infants with the disorder show significant underdevelopment of part or all of the cerebral hemispheres. The EEGs of infants with Ohtahara syndrome reveal a characteristic pattern of high voltage spike wave discharge followed by little activity. This pattern is known as burst suppression. Doctors have observed that boys are more often affected than girls.


Antiepileptic drugs are used to control seizures, but are unfortunately not usually very effective for this disorder. Corticosteroids are occasionally helpful. In cases where there is a focal brain lesion (damage contained to one area of the brain) surgery may be beneficial. Other therapies are symptomatic and supportive.


The course of Ohtahara syndrome is severely progressive. Seizures become more frequent, accompanied by delays in physical and cognitive development.Some children will die in infancy; others will survive but be profoundly handicapped. As they grow, some children will progress into other epileptic disorders such as West syndrome and Lennox-Gestaut syndrome.


The NINDS conducts and supports an extensive research program on seizures and seizure-related disorders. Much of this research is aimed at increasing scientific understanding of these disorders and finding ways to prevent, treat, and potentially cure them.


Postural orthostatic tachycardia syndrome (POTS) is one of a group of disorders that have orthostatic intolerance (OI) as their primary symptom. OI describes a condition in which an excessively reduced volume of blood returns to the heart after an individual stands up from a lying down position. The primary symptom of OI is lightheadedness or fainting. In POTS, the lightheadedness or fainting is also accompanied by a rapid increase in heartbeat of more than 30 beats per minute, or a heart rate that exceeds 120 beats per minute, within 10 minutes of rising. The faintness or lightheadedness of POTS are relieved by lying down again. Anyone at any age can develop POTS, but the majority of individuals affected (between 75 and 80 percent) are women between the ages of 15 to 50 years of age. Some women report an increase in episodes of POTS right before their menstrual periods. POTS often begins after a pregnancy, major surgery, trauma, or a viral illness. It may make individuals unable to exercise because the activity brings on fainting spells or dizziness.

Doctors aren't sure yet what causes the reduced return of blood to the heart that occurs in OI, or why the heart begins to beat so rapidly in POTS. Current thinking is that there are a number of mechanisms. Some individuals have peripheral denervation (neuropathic POTS); some have symptoms that are due to sustained or parosyxmal overactivity of the sympathetic nervous system (hyperadrenergic POTS); and many individuals with POTS have significant deconditioning.


Therapies for POTS are targeted at relieving low blood volume or regulating circulatory problems that could be causing the disorder. No single treatment has been found to be effect for all. A number of drugs seem to be effective in the short term. Whether they help in long term is uncertain. Simple interventions such as adding extra salt to the diet and attention to adequate fluid intake are often effective. The drugs fludrocortisone (for those on a high salt diet) and midodrine in low doses are often used to increase blood volume and narrow blood vessels. Drinking 16 ounces of water (2 glassfuls) before getting up can also help raise blood pressure. Some individuals are helped by beta receptor blocking agents. There is some evidence that an exercise program can gradually improve orthostatic tolerance.


POTS may follow a relapsing-remitting course, in which symptoms come and go, for years. In most cases (approximately 80 percent), an individual with POTS improves to some degree and becomes functional, although some residual symptoms are common.


The National Institute of Neurological Disorders and Stroke (NINDS) and other Institutes of the National Institutes of Health (NIH) conduct research related to POTS and support additional research through grants to major research institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure disorders such as POTS. NINDS-funded researchers are investigating if low levels of the hormone aldosterone contribute to low blood volume in individuals with POTS, and if high levels of angiotensin II, a peptide that helps regulate blood volume, leads to decreased adrenal sensitivity. Other NINDS-funded research is investigating the hypothesis that POTS is a syndrome of different subtypes, with different underlying mechanisms. Additionally, the NINDS funds the Autonomic Rare Diseases Consortium to further understand disorders such as orthostatic hypotension and hopefully alter the course of disease.


Rasmussens encephalitis is a rare, chronic inflammatory neurological disease that usually affects only one hemisphere of the brain. It usually occurs in children under the age of 10 (more rarely in adolescents and adults), and is characterized by frequent and severe seizures, loss of motor skills and speech, paralysis on one side of the body (hemiparesis), inflammation of the brain (encephalitis), and mental deterioration. Most individuals with Rasmussens encephalitis will experience frequent seizures and progressive brain damage in the affected hemisphere of the brain over the course of the first 8 to 12 months, and then enter a phase of permanent, but stable, neurological deficits. Rasmussens encephalitis has features of an autoimmune disease in which immune system cells enter the brain and cause inflammation and damage.Research is ongoing into the causes of this rare disease.


Anti-epileptic drugs are usually not effective in controlling seizures. Recent studies have shown some success with treatments that suppress or modulate the immune system, in particular those that use corticosteroids, intravenous immunoglobulin, or tacrolimus. Surgery to control seizures may be performed in later stages of the disease when neurological deficits stabilize. Surgical procedures, such as functional hemispherectomy and hemispherotomy, may reduce the frequency of seizures and also improve behavior and cognitive abilities.


The prognosis for individuals with Rasmussens encephalitis varies. Despite the advances in medical treatment, none has yet been shown to halt the progress of the disease in the long term. The disorder may lead to severe neurological deficits or it may cause only milder impairments. For some children, surgery decreases seizures. However, most individuals with Rasmussens encephalitis are left with some paralysis, cognitive deficits, and problems with speech. In some cases, the disease can progress to involve the opposite brain hemisphere.


The National Institute of Neurological Disorders and Stroke (NINDS) conducts research related to Rasmussens encephalitis in its laboratories at the National Institutes of Health (NIH), and also supports additional research through grants to major research institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure progressive neurological disorders, such as Rasmussens encephalitis.


Sydenham chorea (SD) is a neurological disorder of childhood resulting from infection via Group A beta-hemolytic streptococcus (GABHS), the bacterium that causes rheumatic fever. SD is characterized by rapid, irregular, and aimless involuntary movements of the arms and legs, trunk, and facial muscles. It affects girls more often than boys and typically occurs between 5 and 15 years of age. Some children will have a sore throat several weeks before the symptoms begin, but the disorder can also strike up to 6 months after the fever or infection has cleared. Symptoms can appear gradually or all at once, and also may include uncoordinated movements, muscular weakness, stumbling and falling, slurred speech, difficulty concentrating and writing, and emotional instability. The symptoms of SD can vary from a halting gait and slight grimacing to involuntary movements that are frequent and severe enough to be incapacitating. The random, writhing movements of chorea are caused by an auto-immune reaction to the bacterium that interferes with the normal function of a part of the brain (the basal ganglia) that controls motor movements. Due to better sanitary conditions and the use of antibiotics to treat streptococcal infections, rheumatic fever, and consequently SD, are rare in North America and Europe. The disease can still be found in developing nations.


There is no specific treatment for SD. For people with the mildest form, bed rest during the period of active movements is sufficient. When the severity of movements interferes with rest, sedative drugs, such as barbiturates or benzodiazepines, may be needed. Antiepileptic medications, such as valproic acid, are often prescribed. Doctors also recommend that children who have had SD take penicillin over the course of the next 10 years to prevent additional manifestations of rheumatic fever.


Most children recover completely from SD, although a small number will continue to have disabling, persistent chorea despite treatment. The duration of symptoms varies, generally from 3 to 6 weeks, but some children will have symptoms for several months. Cardiac complications may occur in a small minority of children, usually in the form of endocarditis. In a third of the children with the disease, SD will recur, typically 1  to 2  years after the initial attack. Researchers have noted an association between recurrent SD and the later development of the abrupt onset forms of obsessive-compulsive disorder, attention deficit/hyperactivity disorder, tic disorders, and autism, which they call PANDAS, for Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus infection. Further studies are needed to determine the nature of the association and the biological pathways that connect streptococcal infection, autoimmune response, and the later development of these specific behavioral disorders.


The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to SD in laboratories at the NIH, and support additional research through grants to major medical institutions across the country. Currently, researchers are studying how the interplay of genetic, developmental, and environmental factors could determine a childs vulnerability to SD after a GABHS infection. Other researchers are exploring whether children whose symptoms either begin or get worse following a GABHS infection share a common set of abnormal biomolecular pathways responsible for their similar clinical symptoms.


Fahr's Syndrome is a rare, genetically dominant, inherited neurological disorder characterized by abnormal deposits of calcium in areas of the brain that control movement, including the basal ganglia and the cerebral cortex. Symptoms of the disorder may include deterioration of motor function, dementia, seizures, headache, dysarthria (poorly articulated speech), spasticity (stiffness of the limbs) and spastic paralysis, eye impairments, and athetosis (involuntary, writhing movements). Fahr's Syndrome can also include symptoms characteristic of Parkinson's disease such as tremors, muscle rigidity, a mask-like facial appearance, shuffling gait, and a "pill-rolling" motion of the fingers. These symptoms generally occur later in the development of the disease. More common symptoms include dystonia (disordered muscle tone) and chorea (involuntary, rapid, jerky movements). Age of onset is typically in the 40s or 50s, although it can occur at any time in childhood or adolescence.


There is no cure for Fahr's Syndrome, nor is there a standard course of treatment. Treatment addresses symptoms on an individual basis.


The prognosis for any individual with Fahr's Syndrome is variable and hard to predict. There is no reliable correlation between age, extent of calcium deposits in the brain, and neurological deficit. Since the appearance of calcification is age-dependent, a CT scan could be negative in a gene carrier who is younger than the age of 55.


The NINDS supports and conducts research on neurogenetic disorders such as Fahr's Syndrome. The goals of this research are to locate and understand the actions of the genes involved in this disorder. Finding these genes could lead to effective ways to treat and prevent Fahr's Syndrome.


Lactose is a sugar found in milk and milk products. The small intestinethe organ where most food digestion and nutrient absorption take placeproduces an enzyme called lactase. Lactase breaks down lactose into two simpler forms of sugar: glucose and galactose. The body then absorbs these simpler sugars into the bloodstream.


Lactose intolerance is a condition in which people have digestive symptomssuch as bloating, diarrhea, and gasafter eating or drinking milk or milk products.

Lactase deficiency and lactose malabsorption may lead to lactose intolerance:

- Lactase deficiency. In people who have a lactase deficiency, the small intestine produces low levels of lactase and cannot digest much lactose.  - Lactose malabsorption. Lactase deficiency may cause lactose malabsorption. In lactose malabsorption, undigested lactose passes to the colon. The colon, part of the large intestine, absorbs water from stool and changes it from a liquid to a solid form. In the colon, bacteria break down undigested lactose and create fluid and gas. Not all people with lactase deficiency and lactose malabsorption have digestive symptoms.

People have lactose intolerance when lactase deficiency and lactose malabsorption cause digestive symptoms. Most people with lactose intolerance can eat or drink some amount of lactose without having digestive symptoms. Individuals vary in the amount of lactose they can tolerate.

People sometimes confuse lactose intolerance with a milk allergy. While lactose intolerance is a digestive system disorder, a milk allergy is a reaction by the bodys immune system to one or more milk proteins. An allergic reaction to milk can be life threatening even if the person eats or drinks only a small amount of milk or milk product. A milk allergy most commonly occurs in the first year of life, while lactose intolerance occurs more often during adolescence or adulthood.1,2

Four Types of Lactase Deficiency   Four types of lactase deficiency may lead to lactose intolerance:   - Primary lactase deficiency, also called lactase nonpersistence, is the most common type of lactase deficiency. In people with this condition, lactase production declines over time. This decline often begins at about age 2; however, the decline may begin later. Children who have lactase deficiency may not experience symptoms of lactose intolerance until late adolescence or adulthood. Researchers have discovered that some people inherit genes from their parents that may cause a primary lactase deficiency.   - Secondary lactase deficiency results from injury to the small intestine. Infection, diseases, or other problems may injure the small intestine. Treating the underlying cause usually improves the lactose tolerance.   - Developmental lactase deficiency may occur in infants born prematurely. This condition usually lasts for only a short time after they are born.   - Congenital lactase deficiency is an extremely rare disorder in which the small intestine produces little or no lactase enzyme from birth. Genes inherited from parents cause this disorder.


Four types of lactase deficiency may lead to lactose intolerance:

- Primary lactase deficiency, also called lactase nonpersistence, is the most common type of lactase deficiency. In people with this condition, lactase production declines over time. This decline often begins at about age 2; however, the decline may begin later. Children who have lactase deficiency may not experience symptoms of lactose intolerance until late adolescence or adulthood. Researchers have discovered that some people inherit genes from their parents that may cause a primary lactase deficiency.  - Secondary lactase deficiency results from injury to the small intestine. Infection, diseases, or other problems may injure the small intestine. Treating the underlying cause usually improves the lactose tolerance.  - Developmental lactase deficiency may occur in infants born prematurely. This condition usually lasts for only a short time after they are born.  - Congenital lactase deficiency is an extremely rare disorder in which the small intestine produces little or no lactase enzyme from birth. Genes inherited from parents cause this disorder.


Common symptoms of lactose intolerance include

- abdominal bloating, a feeling of fullness or swelling in the abdomen  - abdominal pain  - diarrhea  - gas  - nausea

Symptoms occur 30 minutes to 2 hours after consuming milk or milk products. Symptoms range from mild to severe based on the amount of lactose the person ate or drank and the amount a person can tolerate.


A health care provider makes a diagnosis of lactose intolerance based on

- medical, family, and diet history, including a review of symptoms  - a physical exam  - medical tests

Medical, family, and diet history. A health care provider will take a medical, family, and diet history to help diagnose lactose intolerance. During this discussion, the health care provider will review a patients symptoms. However, basing a diagnosis on symptoms alone may be misleading because digestive symptoms can occur for many reasons other than lactose intolerance. For example, other conditions such as irritable bowel syndrome, celiac disease, inflammatory bowel disease, or small bowel bacterial overgrowth can cause digestive symptoms.

Physical exam. A physical exam may help diagnose lactose intolerance or rule out other conditions that cause digestive symptoms. During a physical exam, a health care provider usually

- checks for abdominal bloating  - uses a stethoscope to listen to sounds within the abdomen  - taps on the abdomen to check for tenderness or pain

A health care provider may recommend eliminating all milk and milk products from a persons diet for a short time to see if the symptoms resolve. Symptoms that go away when a person eliminates lactose from his or her diet may confirm the diagnosis of lactose intolerance.

Medical tests. A health care provider may order special tests to provide more information. Health care providers commonly use two tests to measure how well a person digests lactose:

- Hydrogen breath test. This test measures the amount of hydrogen in a persons breath. Normally, only a small amount of hydrogen is detectable in the breath when a person eats or drinks and digests lactose. However, undigested lactose produces high levels of hydrogen. For this test, the patient drinks a beverage that contains a known amount of lactose. A health care provider asks the patient to breathe into a balloon-type container that measures breath hydrogen level. In most cases, a health care provider performs this test at a hospital, on an outpatient basis. Smoking and some foods and medications may affect the accuracy of the results. A health care provider will tell the patient what foods or medications to avoid before the test.  - Stool acidity test. Undigested lactose creates lactic acid and other fatty acids that a stool acidity test can detect in a stool sample. Health care providers sometimes use this test to check acidity in the stools of infants and young children. A child may also have glucose in his or her stool as a result of undigested lactose. The health care provider will give the childs parent or caretaker a container for collecting the stool specimen. The parent or caretaker returns the sample to the health care provider, who sends it to a lab for analysis.


Many people can manage the symptoms of lactose intolerance by changing their diet. Some people may only need to limit the amount of lactose they eat or drink. Others may need to avoid lactose altogether. Using lactase products can help some people manage their symptoms.

For people with secondary lactase deficiency, treating the underlying cause improves lactose tolerance. In infants with developmental lactase deficiency, the ability to digest lactose improves as the infants mature. People with primary and congenital lactase deficiency cannot change their bodys ability to produce lactase.


People may find it helpful to talk with a health care provider or a registered dietitian about a dietary plan. A dietary plan can help people manage the symptoms of lactose intolerance and make sure they get enough nutrients. Parents, caretakers, childcare providers, and others who serve food to children with lactose intolerance should follow the dietary plan recommended by the childs health care provider or registered dietitian.

Milk and milk products. Gradually introducing small amounts of milk or milk products may help some people adapt to them with fewer symptoms. Often, people can better tolerate milk or milk products by having them with meals, such as having milk with cereal or having cheese with crackers. People with lactose intolerance are generally more likely to tolerate hard cheeses, such as cheddar or Swiss, than a glass of milk. A 1.5ounce serving of low-fat hard cheese has less than 1 gram of lactose, while a 1-cup serving of low-fat milk has about 11 to 13 grams of lactose.2

However, people with lactose intolerance are also more likely to tolerate yogurt than milk, even though yogurt and milk have similar amounts of lactose.2

Lactose-free and lactose-reduced milk and milk products. Lactose-free and lactose-reduced milk and milk products are available at most supermarkets and are identical nutritionally to regular milk and milk products. Manufacturers treat lactose-free milk with the lactase enzyme. This enzyme breaks down the lactose in the milk. Lactose-free milk remains fresh for about the same length of time or, if it is ultra-pasteurized, longer than regular milk. Lactose-free milk may have a slightly sweeter taste than regular milk.

Lactase products. People can use lactase tablets and drops when they eat or drink milk products. The lactase enzyme digests the lactose in the food and therefore reduces the chances of developing digestive symptoms. People should check with a health care provider before using these products because some groups, such as young children and pregnant and breastfeeding women, may not be able to use them.


- Lactose is a sugar found in milk and milk products.  - Lactose intolerance is a condition in which people have digestive symptomssuch as bloating, diarrhea, and gasafter eating or drinking milk or milk products.  - A health care provider makes a diagnosis of lactose intolerance based on medical, family, and diet history, including a review of symptoms; a physical exam; and medical tests.  - Basing a diagnosis on symptoms alone may be misleading because digestive symptoms can occur for many reasons other than lactose intolerance.  - Most people with lactose intolerance can tolerate some amount of lactose in their diet and do not need to avoid milk or milk products completely. However, individuals vary in the amount of lactose they can tolerate.  - Research suggests that adults and adolescents with lactose malabsorption could eat or drink at least 12 grams of lactose in one sitting without symptoms or with only minor symptoms. This amount is the amount of lactose in 1 cup of milk.  - Many people can manage the symptoms of lactose intolerance by changing their diet. Some people may only need to limit the amount of lactose they eat or drink. Others may need to avoid lactose altogether.  - People may find it helpful to talk with a health care provider or a registered dietitian to determine if their diet provides adequate nutrients including calcium and vitamin D. To help ensure coordinated and safe care, people should discuss their use of complementary and alternative medical practices, including their use of dietary supplements, with their health care provider.  - Lactose is in all milk and milk products. Manufacturers also often add milk and milk products to boxed, canned, frozen, packaged, and prepared foods. People can check the ingredients on food labels to find possible sources of lactose in food products.


Crohn's disease is a disease that causes inflammation,* or swelling, and irritation of any part of the digestive tractalso called the gastrointestinal (GI) tract. The part most commonly affected is the end part of the small intestine, called the ileum.

*See the Pronunciation Guide for tips on how to say the words in bold type.

Crohns disease is one of two main forms of diseases of the GI tract named inflammatory bowel disease (IBD). The other form, called ulcerative colitis, affects the large intestine, which includes the colon and the rectumthe lower end of the large intestine, leading to the anus.

With Crohns disease, chronicor long lastinginflammation may cause scar tissue to form in the lining of the intestine. When scar tissue builds up, the passage can become narrow, causing food and stool to move through the GI tract more slowlywhich can lead to pain, cramps, and diarrhea.


Both men and women can get Crohn's disease, and it can run in families. People with Crohns disease may have a blood relative with the disease or another type of IBD. Crohns disease most commonly starts between the ages of 13 and 30.


Researchers are studying the possible causes of Crohns disease. Your bodys natural defense system, called the immune system, protects you from infection by fighting against bacteria, viruses, and other things that can make you sick. Researchers believe that with Crohns disease, the immune system attacks harmless bacteria and viruses. During the attack, white blood cells gather in the intestinal lining. The white blood cells cause chronic inflammation, which leads to ulcers, or sores, and damage to the intestines.

Other factors associated with Crohns disease are

- genesthe traits passed down from your parents  - unknown triggers caused by the environment


Crohn's disease symptoms can be different for each person. The most common symptoms of Crohns disease are

- abdominal painoften in the lower right area of the abdomen  - diarrhea  - bleeding in the rectum, which can be seen in a persons underwear, in the toilet, or in a bowel movement; rectal bleeding can be serious and may not stop without medical help  - weight loss  - fever


A doctor will perform a physical exam and tests to diagnose Crohns disease. During your visit, the doctor will ask about your symptoms and medical history.

The doctor may order blood tests, which involve drawing blood at a health care providers office or commercial facility and sending the sample to a lab for analysis. Blood tests can show anemia caused by bleeding. Anemia is a condition in which red blood cells are fewer or smaller than normal, which means less oxygen is carried to the bodys cells. Blood tests can also show a high white blood cell count, a sign of chronic inflammation.

You may also be asked for a stool sample. A stool test is commonly used to rule out other causes of GI diseases, such as infections. The doctor will give you a container for catching and storing the stool. The sample is returned to the doctor or a commercial facility and sent to a lab for analysis. A stool sample can also be used to check if you have bleeding or inflammation.

Other tests may be needed to diagnose Crohn's disease. The following tests are all performed at a hospital or outpatient center.

- Colonoscopy. Colonoscopy is the most commonly used test to specifically diagnose Crohns disease. This test is used to look inside your rectum, entire colon, and ileum. The health care provider will give you written bowel prep instructions to follow at home before the test. You may need to follow a clear liquid diet for 1 to 3 days before the test. You will need to take laxatives and enemas the evening before the test, and you will likely have one or more enemas about 2 hours before the test. A laxative is medicine that loosens stool and increases bowel movements. An enema involves flushing water, laxative, or sometimes a mild soap solution into the anus using a special squirt bottle.  For the test, you will lie on a table while the doctor inserts a flexible tube into your anus. A small camera on the tube sends a video image of the intestinal lining to a computer screen. The doctor can see inflammation, ulcers, or bleeding. The doctor may also perform a biopsy. The doctor will look at the tissue with a microscope to confirm the diagnosis of Crohns disease. In most cases, youll be given a light sedative, and possibly pain medicine, to help you relax. You will not feel the biopsy.  Cramping or bloating may occur during the first hour after the test. Driving is not permitted for 24 hours after the test to allow the sedative time to wear off. Before the appointment, you should make plans for a ride home. By the next day, you should fully recover and go back to your normal diet.    - Flexible sigmoidoscopy. This test is used to look inside the rectum and lower colon. The health care provider will give you written bowel prep instructions to follow at home before the test. You may need to follow a clear liquid diet for 1 to 3 days before the test. You may also need a laxative or enema the night before the test. And youll have one or more enemas about 2 hours before the procedure.  For the test, you will lie on a table while the doctor inserts a flexible tube into your anus. You will not need a sedative for the test. A small camera on the tube sends a video image of the intestinal lining to a computer screen. The doctor can see inflammation, ulcers, or bleeding. The doctor may also perform a biopsy by snipping a bit of tissue from the intestinal lining. The doctor will look at the tissue with a microscope to confirm the diagnosis of Crohns disease. You will not feel the biopsy.  You can usually go back to your normal diet after the test, though you may have cramping or bloating during the first hour after the test.    - Computerized tomography (CT) scan. A CT scan uses x rays and computers to create images of the inside of the body. For the test, you will lie on a table that slides into a tunnel-shaped device where the x rays are taken. The technician may give you a solution to drink and an injection of a special dye through a needle inserted into an arm vein. You will not need a sedative for the test. CT scans can be used to help diagnose Crohn's disease.    - Upper GI series (x rays). An upper GI series may be done to look at the small intestine. No eating or drinking is allowed for 8 hours before the procedure. You will not need a sedative for the test. During the procedure, you will stand or sit in front of an x-ray machine and drink barium, a chalky liquid. The barium coats the small intestine, making signs of the disease show up more clearly on x rays.  After the test, you may go back to your normal diet, though you may have nausea or bloating for a short time. Traces of barium in the GI tract cause stools to be white or light colored for a few days after the test.    - Lower GI series (x rays). A lower GI series may be done to look at the large intestine. The health care provider will give you written bowel prep instructions to follow at home before the test. You will be asked to follow a clear liquid diet for 1 to 3 days before the test. A laxative or enema is usually used the evening before a lower GI series. Enemas are sometimes repeated the morning of the test.  For the test, you will lie on a table while the doctor inserts a flexible tube into your anus. You will not need a sedative for the test. The large intestine is filled with barium, making signs of the disease show up more clearly on x rays. After the test, you may go back to your normal diet, though you may have bloating. You also may have some soreness of the anus. Traces of barium in the GI tract cause stools to be white or light colored for a few days after the test.


Intestinal blockage can occur in people with Crohns disease when scar tissue blocks the intestinal passage. A narrow intestinal passage is called a stricture. When the passage blocks completely, food and stool stop moving, causing abdominal cramps and vomiting. If you have these symptoms, you should see a health care provider right away.

Ulcers from Crohns disease can cause tunnels to form through the inflamed areas, or even the healthy parts, of the intestine. These tunnels are called fistulas. Fistulas are seen most often in the areas around the rectum and anus. Sometimes a pocket of infection, called an abscess, can form in and around the fistulas. Most fistulas can be treated with medicines, but sometimes surgery is needed.

People with Crohns disease often have anemia, which can be caused by the disease itself or by iron deficiency. Anemia may make a person feel tired.

People with Crohns disease, particularly if they have been treated with steroid medicines, may have weakness of their bonescalled osteoporosis or osteomalacia.

People with Crohns disease may also have arthritis, skin problems, swelling in the eyes or mouth, kidney stones, gallstones, and liver problems. Some people with Crohns disease may have restless legs syndromeextreme leg discomfort the person feels while sitting or lying down. These problems may go away during treatment, but some must be treated with medicines.

People who have Crohns disease may not get enough nutrition, such as protein, vitamins, or calories, because they

- have an upset stomach that keeps them from eating enough calories  - may not be able to absorb nutrients in the intestine

Children with Crohns disease may fail to grow normally and may have low height for their age.