Sunday, March 05, 2006

Neurological Complications of Lupus
Terry D. Heiman-Patterson, MD

LEARNING ABOUT LUPUS: A USER FRIENDLY GUIDEFrom the Lupus Foundation of Delaware Valley, Inc.Edited by: Mary E. Moore, Ph.D., M.D., Carolyn H. McGrory, MS, RN, Robert S. Rosenthal, M.D.

Systemic lupus etythematosus (SLE) is a multisystem disorder that frequently affects the nervous system. In fact, of all the connective tissue disorders, lupus has the highest incidence of nervous system complications. These neurologic complications may occur in 30-75 percent of patients. In order to understand the variety of complications, one must have some notion of what makes up the nervous system.

The nervous system contains the brain, brain stem, spinal cord, nerves outside the brain and spinal column (peripheral nerves), and muscle. The brain has centers for speech, movement, sensation, and also more complex functions such as thinking, memory, and personality. The brain relays commands and messages to other areas of the nervous system and receives information from these areas, as well. The brain blends together all this information so that persons can interact with their environment. Between the brain and the spinal cord is the brain stem. The brain stem contains nerve cells that control the muscles of eye movement, facial expression, speaking, swallowing, hearing and balance. The spinal cord contains nerve cells that supply impulses to and from the muscles (i.e., innervate the muscles), and that receive sensory information from the skin and joints.

Muscles attach to bones and when they contract they enable a person to move. Information travels from the brain to the brain stem and spinal cord where contact is made with the nerve cells, (i.e. the cranial and peripheral nerves) innervating muscles of the head and arms and legs. Sensory information is also relayed from these areas through contacts in the spinal cord and brain stem to the sensory centers of the brain. There are several possible ways that lupus can damage the nervous system. First, the blood vessels of the brain may themselves be damaged, leading to poor blood flow, to death of brain tissue (strokes), or to bleeding (hemorrhage). There may be an immune system attack on the nervous system because of antibodies that are produced. These can cause problems directly by attacking nerve cells (antineuronal antibodies) or indirectly by causing blood clots in the brain (lupus anticoagulants or anticardiolipin antibodies).

When lupus affects the nervous system, the type of symptom and the distribution of complaints will depend on what area of the nervous system is involved and on what sensory and motor pathways are damaged. When there is more general involvement of the brain, a patient may demonstrate personality changes and psychiatric disorders. Actual psychosis (severe mental illness) can occur, or mood changes such as depression, or even an unnatural feeling of well-being (euphoria) can occur. Other patients may experience anxiety that is out of proportion to the problems they are experiencing. in all these psychiatric disorders, thinking and memory are normal. However, some patients may actually have loss of intellectual skills (i.e., dementia), or experience confusion and altered consciousness, (sleepiness and even coma). Although confusion and altered consciousness may occur because of direct involvement of the brain by lupus, it can also occur because of drugs used in the treatment of lupus (i.e. steroids) or because of other complications from lupus (i.e. infection, kidney failure).

In these instances, withdrawal of the drug, treatment of the infection, or management of the other systemic complications will help to clear the confusion and improve alertness. Another complication due to brain involvement is having seizures or convulsions. These can occur in up to 20% of patients. In patients with kidney failure due to lupus, the rate of seizures rises to almost 50 percent. Lupus can also cause strokes in which there is a sudden onset of neurologic symptoms. Strokes can be due to bleeding into the brain or to death of brain tissue because of lack of blood flow. These problems occur if there is inflammation of blood vessels, clotting of blood within vessels, or not enough clotting of blood causing patients to hemorrage more readily. Patients with strokes may have a variety of symptoms, including loss of sensation on one side of the body, loss of movement (paralysis) on one side of the body, problems with verbal expression, or problems with vision.

The exact symptoms will depend on what area of the brain is damaged. Headaches can occur in 20-25 percent of lupus patients. These are most like migraine headaches that are pounding, associated with nausea and vomiting, and cause photophobia (light hurting the eyes). Other much rarer complications due to brain damage relate to problems with coordinated movements. Brain stem involvement with lupus also causes a variety of symptoms. These are primarily due to involvement of the nerves to the muscles of the head and of the sensory pathways from the face. Problems with movement of the eyes can cause double vision. Inflammation of the nerve for vision can cause blurring of vision.

Sensation or movement of the face can be altered, causing numbness or tingling or weakness of the face. In addition, other symptoms of brain stem involvement include hearing problems, slurred speech, and trouble swallowing. Since the longer nerve pathways that carry motor and sensory information between the brain and spinal cord may also be damaged in the brain stem, there may be sensory and motor symptoms, not only of the head and face, but also in the arms and legs. Spinal cord involvement is very rare. When it does occur, it is called "myelopathy" and patients may not be able to move their arms and legs depending on what section of the spinal cord is involved. In addition, sensation is also changed below the area of the spinal cord that is involved. The patient may not feel pain or temperature properly. Other sensations may also be affected such as the ability to feel a vibration or to sense the body's position.

Lupus can imitate inflammation of the spinal cord that is usually due to other diseases such as multiple sclerosis. These symptoms require careful examination to determine their cause. The peripheral nervous system includes the rest of the motor and sensory nerves and the muscles. It includes the nerves that come from the spinal cord to all parts of the body. The peripheral motor nerves carry motor information (originating in the brain) from the spinal cord to the muscle. The muscle will then contract so movement can occur. The sensory fibers carry sensory information from the skin, joints, and muscle to the spinal cord, where it can then be relayed back to the brain. Damage to the peripheral nerves occurs in 10-15 percent of patients with lupus and can result in numbness (pins and needles sensation) of the feet and hands, an inability to feel a pin prick, temperature change, vibration, or change in position, and weakness. If this peripheral nerve damage is severe, patients may inadvertently hurt themselves without knowing it.

If this becomes a frequent occurrence, it can lead to infections, ulcerations, and joint problems. Sometimes individual peripheral nerves to the arm or leg can be damaged. This results in more local sensation and movement problems. Finally, some types of sensation may be more affected than others. If position sense is altered, difficulties with walking may result. This is due to an inability to sense where the feet are being placed. In addition to peripheral nerve involvement, the muscle can also be involved with inflammation or other nonspecific damage. This occurs in 5-30 percent of patients. Patients with muscle problems will experience weakness of the thighs and shoulders. They may have trouble arising from chairs or going up stairs. There will be complaints related to combing the hair and putting things up on a shelf. There may also be some muscle tenderness.

When patients with lupus are clearly weak, other factors should also be considered, i.e. steroid-induced weakness and weakness due to other problems from lupus. Kidney disease, poor nutrition, or immobility can all lead to muscle weakness. When neurologic complications begin, the first step is to identify lupus as the causative factor and make sure all other possible causes are considered (i.e., infection, anemia, kidney failure, drug toxicities). If they are present, these other causes should then be treated appropriately. On the other hand, if the complication is primarily due to lupus, then treatment of the lupus itself is necessary.

=========================================================== This information is for "informational purposes" and is not meant to be used for medical diagnosis. Always consult your physician on matters such as this.

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