Disorders of the peripheral nerves, the nerves that branch from the brain and spinal cord to the rest of the body, are called neuropathies. Depending on the nerves affected, peripheral neuropathies may affect sensation, movement, or automatic functions, such as bladder control. Rarely, a peripheral neuropathy may be life-threatening.

What are the causes?

In developed countries, the most common cause of damage to the peripheral nerves is diabetes mellitus. Vitamin B complex deficiencies and some nutritional disorders may also result in nerve damage. In the developed world, nutritional neuropathy is often the result of a poor diet in people who abuse alcohol. Drinking too much alcohol may also damage peripheral nerves directly.

Damage to a single nerve may occur as a result of an injury or because of compression. For example, in carpal tunnel syndrome, the median nerve, which supplies that part of the hand, is compressed at the wrist.

Neuropathy may also be associated with an infection, such as Hansen’s disease or HIV infection. Guilain-Barre syndrome, a neuropathy that is rapidly progressive, is caused by an abnormal immune response that sometimes occurs after an infection.

Autoimmune disorders such as systemic lupus erythematosus, in which the immune system attacks the body’s tissues, may cause nerve damage occasionally, a disorder such as polyarteritis nodosamay damage nerves by causing inflammation of the blood vessels that supply them. Neuropathy may also result from certain cancers, particularly primary lung cancer and lymphoma. Occasionally, neuropathy is caused by amyloidosis, in which an abnormal protein is deposited in the body.

Some drugs, such as isoniazid, may cause nerve damage, as may exposure to certain toxic substances, such as lead. In some cases, the cause is unknown.

A painless ulcer developing under the big toe joint due to peripheral neuropathy

What are the types?

Peripheral neuropathies may affect the nerves that transmit sensory information (sensory nerves), the nerves that stimulate the muscles (motornerves), and/or the nerves that control automatic functions (autonomic nerves).

Sensory nerve neuropathies: these neuropathies first affect the hands and feet and the spread towards the centre of the body. The symptoms may include tingling, pain, and numbness in the affected area. If the fingertips are numb, everyday tasks may become difficult. This type of neuropathy is most often caused by nutritional disorders or drugs.

Motor nerve neuropathies: if the motor nerves are damaged, the muscles they supply become weak, and wasting occurs eventually. In severe cases, mobility may become restricted, and very rarely, breathing may have to be assisted by mechanical ventilation. Lead poisoning may result in a neuropathy that affects the motor nerves only.

Autonomic nerve neuropathies: a neuropathy that is affecting one or more autonomic nerves may result in constipation, fainting due to low blood pressure, diarrhoea, urinary in continence, or impotence. This type of neuropathy is often caused by long-standing diabetes mellitus.

What might be done?

Your doctor may be able to tell which nerves are affected from your symptoms and an examination. If the cause of your neuropathy is not clear, he or she will probably arrange for blood tests to look for evidence of an underlying disorder, such as nutritional deficiencies or an autoimmune disorder. If Mere is evidence of compression of a nerve, you may also have CT scanning or MRI to assess the severity and extent of nerve damage. Special tests to assess the function of the nerves may also be carried out.

The treatment of a peripheral neuropathy depends on the cause and the type of nerve affected. For example, careful control of diabetes mellitus may keep diabetic neuropathy from worsening, and vitamin B complex injections may help a nutritional neuropathy. If motor nerves are affected, you may have physiotherapy to help to maintain muscle tone. Wearing a foot splint may assist walking. Sometimes, the underlying cause can be treated, but long-standing nerve damage may be irreversible.


TEST NERVE AND MUSLCE ELECTRICAL TESTS

Nerve and muscle electrical test consist of nerve conduction studies and electromyography (EMG). Nerve conduction studies are used to assess how well a nerve is conducting electrical impulses. They are often followed by EMG to see whether symptoms, such as weakness, are due to a disorder of the muscle or the nerve supplying it. Both tests are usually done on an outpatient basis. Each takes about 15 minutes and may cause discomfort.

Nerve conduction studies

Nerve conduction studies are carried out to assess nerve damage in disorders such as peripheral neuropathies. A nerve is stimulated by an electrical impulse, and the response to the stimulus and the speed at which this response travels along the nerve indicates whether the nerve is damaged and the nature and extent of the damage.

Electromyography

EMG is used to differentiate between nerve and muscle disorders and to diagnose disorders such as muscular dystrophy. A fine needle is used to record the electrical activity of a muscle at rest and when contracting. The results are recorded on a trace.

Read more…

Multiple sclerosis (MS) is the most common nervous system disorder affecting young adults. In this condition, nerves in the brain and spinal cord are progressively damaged, causing a wide range of symptoms that affect sensation, movement, body functions, and balance. Specific symptoms may relate to the particular areas that are damaged and vary in severity between individuals. For example, damage to the optic nerve may cause blurred vision. If nerve fibres in the spinal cord are affected, it may cause weakness and heaviness in the legs or arms. Damage to nerves in the brain stem, the area of the brain that connects to the spinal cord, may affect balance.

In many people with MS, symptoms occur intermittently and there may be long periods of remission. However, some people have chronic (long-term) symptoms that gradually get worse.

In the UK, about 85,000 people are affected by MS. People who have a close relative with MS are more likely to develop the disorder. The condition is much more common in the northern hemisphere, which suggests that environmental factors also play a part. MS is more common in females and the disorder is more likely develop between early adulthood and middle age.

What are the causes?

MS is an autoimmune disorder, in which the body’s immune system attacks its own tissue, in this case those of the nervous system. Many nerves in the brain and spinal cord are covered by a protective insulating sheath of material called myelin. In MS, small areas of myelin are damaged, leaving holes in the sheath, a process known as demyelination. Once the myelin sheath has been damaged, impulses cannot be conducted normally along nerves to and from the brain and spinal cord. At first, the damage may be limited to only one nerve, but myelin covering other nerves may become damaged over time. Eventually, damaged parches of myelin insulation are replaced by scar tissue.

It is thought that MS may be triggered by external factors such as a viral infection during childhood in genetically susceptible individuals.

What are the types?

There are two types of MS. In the most common, known as relapsing remitting MS, symptoms last for days or weeks and then clear up for months or even years. However, some symptoms may eventually persist between the attacks. About 3 in 10 people with MS have a type known as chronic-progressive MS, in which there is a gradual worsening of symptoms with no remission.

A person with relapsing-remitting MS may go on to develop chronic-progressive MS.

What are the symptoms?

Symptoms may occur singly in the initial stages and in combination as the disorder progresses. They may include:

- Blurred vision.
- Numbness or tingling in any part of the body.
- Tiredness, which may be persistent.
- Weakness and a feeling of heaviness in the legs or arms.
- Problems with coordination and balance, such as an unsteady gait.

Stress and heat sometimes make symptoms worse. About half of the people who have MS find it hard to concentrate and experience memory lapses. Depression is common. Later in the course of the disease, some people with muscle weakness develop painful muscle spasms. Spinal cord damage can lead to urinary incontinence, and men may have increasing difficulty in achieving an erection. Eventually, damage to myelin covering nerves in the spinal cord may cause partial paralysis, and an affected person may need a wheelchair.

How is it diagnosed?

There is no single test to diagnose MS, and, because symptoms are so wide-ranging, a diagnosis is only made once other possible causes of the symptoms have been excluded. Your doctor will take your medical history and carry out a physical examination. If you are having visual problems, such as blurred vision, you may be referred to an ophthalmologist, who will assess the optic nerve, which is commonly affected in the early stages of the disorder. Your doctor may arrange for tests to find out how quickly your brain receives messages when particular nerves are stimulated. The most common test measures damage to the visual pathways. You will probably also have an imaging test of the brain, such as MRI, to see if there are areas of demyelination.

Your doctor may arrange for a lumbar puncture, a procedure in which a small amount of the fluid that surrounds the spinal cord is removed for microscopic analysis. Abnormalities in this fluid may confirm the diagnosis.

What is the treatment?

There is no cure for MS, but if you have relapsing-remitting MS, interferon beta may help to lengthen remission periods and shorten the length of attacks. Your doctor may also prescribe corticosteroids to shorten the duration of a relapse. However, at present, there is no specific treatment to halt the progression of chronic-progressive MS.

Many of the more common symptoms that occur in all types of MS can be relieved by drugs. For example, your doctor may treat muscle spasms with a drug that relaxes muscles. Similarly, incontinence can often be improved by drugs. Problems in getting an erection may be helped by a drugs treatment such as sildenafil. If you have mobility problems, your doctor may arrange for you to have physiotherapy. Occupational therapy may make day-to-day activities easier.

What can I do?

If you are diagnosed with MS, you and your family will need time and possibly counseling to come to terms with the disorder. You should minimize stress in your life and avoid exposure to high temperatures if hear tends to make your symptoms worse. Regular, gentle exercise, such as swimming, will help to keep your muscle strong without the risk of overstraining them.

The progression of MS is extremely variable, but people who are older when the disease first develops tend to fare less well. About 7 in 10 people with MS have active lives with long periods of remission between relapses. However, some people, particularly those with chronic-progressive MS, become increasingly disabled. Half of all people with MS are still leading active lives 10 years after diagnosis, and the average lifespan from diagnosis is 25-30 years.


VISUAL EVOKED RESPONSES

A visual evoked response test measure the function of the optic nerve, the nerve that transmits messages from the eye to the brain. The test is most often used to in the diagnosis of multiple sclerosis and can detect abnormalities even if visual symptoms are not apparent. The test records brain activity in response to a visual stimulus to find out the speed at which messages from the eye reach the brain. The test takes 20-30 minutes.

Read more…

Motor neuron disease is rare, affecting 1-2 people in every 100,000 worldwide each year. In this disease, also known as amyotrophic lateral sclerosis, degeneration of the nerves involved in muscular activity results in progressive wasting of the muscles and weakness. There are several types of motor neuron disease. Some affect mainly the spinal nerves, while other types also affect the brain. The condition is not painful, does not affect bowel or bladder function, and does not usually affect the intellect or the senses, such as sight.

Steven Hawkins is the one of few people to ever live passed 5 years with MND. 

He has lived for around 40 years

The cause of motor neuron disease is unknown. Genetic factors are involved because, in about 1 in 10 cases, the disease runs in the family. The disease is slightly more common in men and usually develops after the age of 40.

What are the symptoms?

Initially, weakness and wasting develop over a few months and usually affect the muscles of the hands, arms, or legs. Other early symptoms may include:

- Twitching movements in the muscles.
- Stiffness and muscle cramps.
- Difficulty in carrying out twisting movements, such as unscrewing bottle tops and turning keys.

As the disease progresses, other symptoms may include:

- Dragging one foot or a tendency to stumble when walking.
- Difficulty in climbing stairs or getting up from low chairs.

Less commonly, the muscles of the mouth and throat are involved, and may cause slurred speech, hoarseness, and difficulty in swallowing.

An affected person may have mood swings and may become anxious and depressed. If the muscles involved in breathing and swallowing are affected, small particles of food may enter the lungs and cause recurrent chest infections and possibly pneumonia. The head may fall forwards because the muscles in the neck are too weak to support it. Eventually, weakness of the muscles that control respiration may cause difficulty in breathing.

How is diagnosed?

There is no specific test to diagnose motor neuron disease. However, electromyography may be carried out to detect a decrease in electrical activity in the muscles. Additional tests may be used to exclude other possible causes of the symptoms. For example, MRI or CT scanning of the brain and neck may be used to exclude a local problem such as a tumour or cervical spondylosis.

What is the treatment?

At present, no treatment can significantly slow down the progression of motor neuron disease, although a new drug called riluzole may have a small effect. Treatment for symptoms may include antidepressants to relieve depression and antibiotics to treat chest infections. If the person is having difficulty in swallowing, a gastrostomy maybe created surgically. This is an opening through which a permanent feeding tube is inserted directly into the stomach or the small intestine.

Usually, a team of specialists provide support and care for an affected person and members of the family. Counseling may be offered to both. The person affected by the disease may have physiotherapy to keep joints and muscles supple and may be given aids to help with activities such as eating and walking. A speech therapist can supply communication aids to help with speech difficulties and advise on swallowing problems. Joining a self-help group is often helpful to person with motor neuron disease and his or her family.

The outlook for motor neuron disease is variable, with approximately 2 in 10 affected people alive 5 years after diagnosis. About 1 in 10 affected people survives more than 10 years.

Read more…

Creutzfeldt-Jakob disease (CJD) is an extremely rare condition in which brain tissue is progressively destroyed by an unusual infectious agent. The disorder leads to a general decline in all areas of mental, and physical ability and ultimately to death. CJD affects about one person in a million each year worldwide.

What is the cause?

CJD is caused by an infectious agent known as a prion, which replicates in the brain and causes brain damage. One type of CJD, accounting for 15 in 100 cases, has been found to run in families.

Most people who develop CJD are over the age of 50. Usually, the source of the infection is unknown, but in about 1 in 20 people it can be traced to earlier treatment with products derived from human tissue. Before the use of artificial growth hormones to treat growth disorders, human growth hormone injections were one source of infection.

In the mid 1990s, a new, rare variant of CJD that affects people in their teens or 20s was discovered in the UK. By the year 2000, about 50 cases had been reported. This variant is believed to be linked with eating contaminated meat from cattle with a disease called bovine spongiform encephalopathy (BSE).

What are the symptoms?

It is thought that is present for 2-15 years before symptoms begin to develop gradually. They may include:

- Depression.
- Poor memory.
- Unsteadiness and poor coordination.

Other symptoms develop as the condition progresses and include:

- Sudden muscle contractions.
- Seizures.
- Weakness or paralysis on one side of the body.
- Progressive dementia.
- Impaired vision.

In the later stages CJD, a person may be unable to move and talk. Those who are confined to bed are prone to serious lung infections.

What might be done?

CJD is usually diagnosed from a person’s symptoms because no specific test is yet available. Anyone suspected of having CJD will have extensive tests, such as MRI, to exclude other treatable causes, and EEG to look for characteristic changes in electrical activity in the brain. A brain biopsy, in which a small piece of tissue is surgically removed for examination, may be performed. There is no cure for CJD, but drugs can relieve some symptoms. For example, symptoms of depression may be treated with antidepressant drugs, and muscle contractions may be controlled by muscle relaxant drugs. However, the disorder is usually fatal within 3 years.

Read more…

Parkinson’s disease results from degeneration of cells in a part of the brain called the basal ganglia, which controls the smoothness of muscle movements. Normally, these cells produce a neurotransmitter (a chemical that transmits nerve impulses) called dopamine, which acts with acetylcholine, an other neuro-transmitter, to fine-tune muscle control. In Parkinson’s disease, the level of dopamine relative to acetylcholine is reduced, adversely affecting muscle control.

About 1 in 200 people in the UJ has Parkinson’s disease. The disorder tends to occur after the age of 60 and is more common in men.

Parkinsonism is the term used for symptoms of Parkinson’s disease when they are due to an underlying disorder or certain drugs. Repeated head injuries may cause Parkinsonism, as may some antipsychotic drugs used to treat severe psychiatric illness.

What are the symptoms?

The main symptoms of Parkinson’s disease develop gradually over months or even years. Parkinsonism may have a gradual or sudden onset depending on the cause. Symptoms include:

- Tremor of on hand, arm or leg, usually when resting, that later occurs on both sides.
- Muscle stiffness, making it difficult to start moving.
- Slowness of movement.
- Shuffling walk with loss of arm swing.
- Expressionless or mask-like face.
- Stooped posture.

As the disease progresses, stiffness, immobility, and constant trembling of the hands may make some daily tasks difficult to perform. Speech may become slow and hesitant, and swallowing may be difficult. Many people with the disorder develop depression. About 3 in 10 people with the disease eventually develop dementia.

How is it diagnosed?

Since Parkinson’s disease begins gradually, it is often not possible to diagnose the condition immediately. Your doctor will examine you and may arrange tests such as CT scanning or MRI to exclude other possible causes. If a specific underlying disorder is found to be causing your symptoms, you will be diagnosed as having Parkinsonism rather than Parkinson’s disease.

How might the doctor treat it?

There is no specific cure for Parkinson’s disease, but drugs physical treatments, and more rarely, surgery can relieve symptoms. If you have Parkinsonism due to medications, your doctor may change your drugs. Symptoms the usually disappear within 8 weeks. If the symptoms persist, you may need to be treated with anti-parkinsonism drugs.

Drug treatment: in the early stages of Parkinson’s disease when symptoms are mild, treatment may not be necessary because drugs can not change the progression of the disease. Later on, drugs are used to relieve symptoms and reduce disability by correcting chemical imbalances in the brain, either by boosting dopamine levels or by blocking some the effects of acetylcholine or a combination of both. The choice and dosage of drugs is tailored to individual’s particular problems and adjusted to reduce side effects.

Often, an anti-cholinergic drug such as trihexyphenidyl (benzhexol) is given initially to reduce shaking and stiffness. Anti-cholinergic drugs can be effective for several years, but they may cause dry mouth, burred vision and difficulty in passing urine.

The main treatment for Parkinson’s disease is with levodopa, which boosts the level of dopamine within the brain. Levodopa controls major symptoms such as mobility problems but may initially cause side effects, such as nausea and vomiting. For this reason, the drug is increased gradually and is usually prescribed with other drugs, such as carbidopa or benserazide, which reduce the amount of levodopa that is needed. However, some people develop involuntary jerky or writhing movements as a side effect of this treatment. Levodopa is usually effective for 2-5 years, but long-term use may be associated with abrupt changes in symptoms known as the “one-off” effect of levodopa. The affected person has periods of normal mobility punctuated by unpredictable episodes of weakness and difficulty in moving.

When levodopa is no longer effective, seligiline, a drugs that slightly increases dopamine activity in the brain, may be tried, and later, other drugs, including dopamine agonists such s bromocriptine, may be used. Such drugs may cause confusion, hallucinations, and occasionally, aggressive behaviour. Although there is no wholly successful therapy for symptoms of this disease, new drugs are always being developed.

Physical treatment: the doctor may arrange for physiotherapy to help with mobility problems or speech therapy for speech and swallowing problems. If you are finding it difficult to cope at home, an occupational therapist may suggest changes, such as installing hand-rails to make it easier for you to move around.

Surgical treatment: younger people who are otherwise in good health may have surgery if the tremor cannot be controlled by drugs. Surgery involves destroying a part of the brain tissue responsible for the tremor. Therapies still being assessed include replacement of damaged brain cells with transplanted tissue and deep brain stimulation with electrical impulses to reduce tremor. Deep brain stimulation, in particular, holds promise as a future treatment.

What can I do?

It is important to pay attention to your general health. Taking a walk each day and doing simple stretching exercises will help you to maintain strength and mobility. You should also rest during they day to avoid getting tired. Emotional and practical help from family, friends, and support groups is important.

What is the prognosis?

The course of the Parkinson’s disease is variable, but drugs can be effective in treating the symptoms and improving the quality of life. People can lead active lives for many years after being diagnosed. However, most people with the disorder need daily help eventually, and their symptoms may be increasingly hard to control with drugs.

Read more…

Huntington’s disease is an inherited disorder that causes degeneration of a particular part of the brain. Also known as Huntington’s chorea, the condition causes jerky, involuntary movements, clumsiness, and progressive dementia. Huntington’s disease is rare, affecting only about 6,000 people in the UK. The symptoms commonly develop between the ages of 30 and 50.

Huntington’s disease is caused by an abnormal dominant gene. To develop the disease, an affected person has to inherit the abnormal gene from only one parent. People who have the gene have a 1 in 2 chance of passing it on to each of their children. Since the symptoms do not develop until later in life, an abnormal gene may be passed on to children before the affected parent becomes aware that he or she has Huntington’s disease. However, a genetic test can be carried out at any age to find out if an individual has inherited the abnormal gene from a parent.

What are the symptoms?

Symptoms develop gradually over a period of months or years. Initially, they may include the following:

- Jerks and spasms of the face, arms, and trunk.
- Clumsiness.
- Mood swings, including outbursts of aggressive, antisocial behaviour.
- Poor memory, especially for events that have occurred recently.

As the disease progresses, further symptoms of dementia, such as losing the ability to think rationally, may develop. There may be difficulty in speaking and swallowing, and problems with urinary incontinence. Anxiety and depression may also occur.

What might be done?

Unless the condition has already been diagnosed within the family, it may not be recognized during its early stages. Usually, a member of the affected person’s family first realizes that there is a problem. The affected person may be suspicious of others and refuse help. Diagnosis is usually made from the symptoms and by CT scanning or MRI of the brain, which may show distinct patterns of abnormality.

There is no cure for Huntington’s disease, bur drugs may relive certain symptoms. For example, antipsychotic drugs help to control jerks and spasms. Speech therapy and occupational therapy are used to help an affected person to lead as normal a life as possible. However, care in a nursing home may be necessary if the person is unable to live at home or when carers need a period of respite. Members of the family may decide to have a blood test to determine whether they have the abnormal gene themselves. These tests are performed after genetic counseling because the results are likely to have a bearing on whether or not they decide to have children.

Huntington’s disease has a slow progression. A person may live for 15-20 years after the onset of symptoms.

Read more…

Wernicke-Korsakoff syndrome is a rare disorder of the brain, causing dementia, abnormal eye movements, and an abnormal gait. The condition develops rapidly and is due to a severe deficiency of vitamin B1. It is a medical emergency. If untreated, coma and death may occur. About 2 in 10 individuals with the disorder die within 5 days. Vitamin B1 deficiency is usually caused by many years of severe alcohol abuse, but in may be due to extreme mal-nutrion or starvation. This order is most common in people over the age of 45 and affects more men than women.

What are the symptoms?

Symptoms may start gradually or suddenly, sometimes affect heavy drinking, and are easily mistaken for drunkenness. They include the following:

- Abnormal movements of the eyes, which often result in double vision.
- Unsteadiness when walking.
- Confusion and restlessness.

Unless the individual is given urgent treatment, he or she will develop severe memory loss, become drowsy, go into a coma, and eventually die.

What might be done?

A person with Wernicke-Korsakoff syndrome needs immediate admission to hospital for intravenous treatment with high-dose vitamin B1. After treatment, many of the symptoms may be reserved within days, but memory loss may persist. If untreated, the disorder is fatal.

Read more…