How Lupus Can Affect the Nervous System

The immune system normally protects us from outside invaders. In lupus, the immune attacks the body itself. That's why it's called an autoimmune disease. The immune system creates antibodies - which normally attack bacteria and viruses - that attack your own cells. These are called autoantibodies. They cause inflammation in many parts of the body - and inflammation can damage the body.

The nervous system includes the brain and spinal cord and the muscles and peripheral nerves (the nerves in other parts of the body, such as the hands and feet). Any part of that system can be involved in lupus. When a lupus-related problem affects the nervous system, it is called a neurological complication.

Doctors don't really understand why people with lupus develop neurological and psychological problems. About 50% to 90% of people with lupus have some neuropsychiatric symptoms at one time or another. Most have relatively mild problems such as anxiety, headaches, or a little bit of confusion. But some have significant neurological complications. How can lupus cause these problems?

Secondary Problems

Most often, it is not the lupus itself causing neuropsychiatric symptoms - but "secondary problems."

For example, neurological problems may result from drugs you are taking.

People who have lupus often take drugs that suppress (hold back) immune system activity. These are called immunosuppressants, and they increase your risk of infection. An infection, such as meningitis, can cause neurological problems.

Many people with lupus take steroid drugs, such as prednisone. These drugs can do a lot of odd things to your mind and your feelings. It can make you anxious and nervous. It can interfere with sleep. You gain weight. Your muscles can waste away, making you feel weak.

You can also get neurological symptoms from other drugs used to treat lupus.

Complications of the medical problems of lupus, such as kidney or liver disease, can cause neurological symptoms. Kidney and liver failure can cause confusion and disorientation.

The psychological reactions that can arise from having such a serious, chronic disease can cause anxiety, agitation, and depression.

Primary Problems

Lupus also may have a direct - primary - affect on the nervous system. Autoantibodies may attack nerve cells. This is associated the development of encephalopathy - which simply means "brain not working well." That can cause psychosis. The symptoms are confusion, disorientation, and agitation. But remember that these are the same symptoms that can be caused by infection, medications, and the medical or psychiatric problems that occur in lupus. These symptoms also can be caused by seizures that sometimes occur in lupus. However, even when we eliminate the secondary problems, there is still a small group of people who have encephalopathy - a diffuse (widespread) brain dysfunction.

Why does this happen? We don't know. But people who have an antibody to ribosomes are more likely to have this psychosis. Ribosomes are small protein factories in the cells. They take DNA and use its instructions to make proteins. (DNA carries our genetic information.)

How should psychosis be treated in people with lupus? That depends on its origin, how active the lupus is in general. Does the patient have these antibodies? Are there signs of lupus in the nervous system that we can detect by MRI scan - abnormalities in the brain - or by abnormalities in the spinal fluid? If we see an overall picture suggesting an active, inflammatory, phase of the disease, then we give high dose steroids to quiet the lupus. But if the patient does not seem to be having a lupus flare, they need anti-psychotic medication and drugs to ease anxiety.

Lupus can also cause inflammation of the blood vessels, called vasculitis. Usually, small blood vessels are affected. Some doctors think that inflammation of small blood vessels in the brain causes confusion, agitation and encephalopathy. But there's not much evidence to support that idea. Further, vasculitis of the small vessels would cause tiny strokes, which are not common in lupus. This is in contrast to the big strokes that are caused by APS (anti-phospholipid antibody syndrome).

Possibly some of the inflammation of lupus itself can cause anxiety and depression too.

Anti-phospholipid Antibody Syndrome (APS)

Another antibody that can affect the brain is anti-phospholipid antibody. It can affect people with lupus - as well as people who don't have lupus. When this antibody causes symptoms, it's called anti-phospholipid antibody syndrome (APS).

Having these antibodies doesn't mean that your lupus is active. But they can cause the blood to clot. As a result, they increase your risk of:

• miscarriage,
• clots in the veins,
• clots on the heart valve, called Libman-Sacks endocarditis,
• strokes in younger people of the kind that normally occur in older people due to hardening of the arteries.

Having antiphospholipid antibodies also may increase your risk of:

• "livido reticularis" - a blotchy, red discoloration of the legs and arms.
• migraine and migraine-like illnesses,
• rarely, seizures or dementia, which may be related to strokes
• chorea, a fidgety, twitching movement of the arms and legs that you can't voluntarily control and that comes and goes.
• very rarely, myelopathy - a dysfunction of the spinal cord that causes spastic - jerky - movement.

APS is treated very differently from the inflammatory problems of lupus - because it does not mean that your lupus is doing badly. It's a sign that, in addition to your regular lupus treatment, you need to be on anticoagulants - drugs that help prevent blood clots. Usually, that means warfarin (brand-named Coumadin) and/or, in some cases, aspirin.

Peripheral Nerve Problems

About 20% of people with lupus have peripheral nerve abnormalities that show up on certain tests - electromyograms (EMGs) and nerve conduction studies. These are electrical tests of the nerves and muscles. But only about 10% of people with lupus actually have symptoms - called polyneuropathy or peripheral neuropathy. In most people, this is not a major problem. Sometimes it may cause weakness of the hands or legs. Or it may be a sensory neuropathy - abnormal feelings - causing numbness, tingling, or burning of the hands and feet. No one really knows what causes this painful neuropathy. It is treated with painkilling drugs such as gabapentin (Neurontin), amitryptyline (Elavil) or nortryptyline (Pamelor).

Usually, neuropathy is symmetrical - affecting the same part on both sides of the body. But 3% of people with lupus have non-symmetrical neuropathy. It's patchy - a little bit here, a little bit somewhere else - and called mononeuritis multiplex. That's the type that may be caused by vasculitis. It may be a sign of active, inflammatory lupus and need aggressive treatment with steroids and other immunosuppressant drugs.

Muscle Problems

Muscle disease is most unusual in lupus. Myositis - inflammation of the muscles - may occur. People who have polymyositis - another inflammatory disorder of connective tissues - may also have crossover symptoms with lupus. Polymyositis causes weak muscles. Rarely, people with lupus have inflammation of the muscles. It may be caused only by inflammation, or it may be due to inflammation of tiny blood vessels.

But most muscle problems in lupus are due to:

• inactivity, where more physical activity can help, or
• the side effects of steroids, due to muscle loss in the big muscles, such as the thighs and shoulders, which also can be helped by exercise and a reduction in steroid use.

Remember, most people with lupus will never have the problems discussed here. Most of the neuropsychiatric problems in lupus are headache, anxiety, or agitation (feelings of nervousness).

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