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Guillain-Barré syndrome (acute inflammatory demyelinating polyneuropathy) is a form of polyneuropathy causing muscle weakness, which usually worsens over a few weeks, then decreases slowly on its own. With treatment, people may improve more quickly.
The presumed cause is an autoimmune reaction. The body's immune system attacks the myelin sheath, which surrounds the nerve and enables nerve impulses to travel quickly. In about two thirds of people with this syndrome, symptoms begin about 5 days to 3 weeks after a mild infection (such as a Campylobacter infection, mononucleosis, or another viral infection), surgery, or an immunization.
Weakness caused by Guillain-Barré syndrome usually worsens over 3 or 4 weeks. If it worsens for more than 8 weeks, it is considered chronic inflammatory demyelinating polyneuropathy (CIDP), not Guillain-Barré syndrome.
Symptoms
Symptoms usually begin in both legs, then progress upward to the arms. Occasionally, symptoms begin in the arms or head and progress downward. Symptoms include weakness and a pins-and-needles sensation or loss of sensation. Weakness is more prominent than abnormal sensation. Reflexes are decreased or absent. In 90% of people who have Guillain-Barré syndrome, weakness is most severe within 3 weeks. In 5 to 10%, the muscles that control breathing become so weak that a ventilator is needed. Because the facial and swallowing muscles become weak, a few people need to be fed intravenously or through a tube placed directly through the abdominal wall into the stomach (gastrostomy tube).
If the disorder is very severe, internal functions controlled by the autonomic nervous system may be impaired. For example, blood pressure may fluctuate widely, heart rhythm may become abnormal, and severe constipation may develop.
In a variant called Miller-Fisher syndrome, only a few symptoms develop: Eye movements become paralyzed, walking becomes difficult, and normal reflexes disappear.
Diagnosis
Doctors suspect the diagnosis based on the pattern of symptoms. Tests are done to confirm the diagnosis. People are admitted to the hospital to have the tests because the syndrome can worsen rapidly and impair the muscles involved in breathing.
Analysis of cerebrospinal fluid obtained by a spinal tap (lumbar puncture—see Symptoms and Diagnosis of Brain, Spinal Cord, and Nerve Disorders: How a Spinal Tap Is Done ), electromyography, nerve conduction studies, and blood tests can help doctors exclude other possible causes of severe weakness, such as transverse myelitis (inflammation of the spinal cord) and spinal cord injuries. A combination of high protein levels and few or no white blood cells in the cerebrospinal fluid and characteristic results from electromyography strongly suggest Guillain-Barré syndrome.
Prognosis
Damage stops progressing within 8 weeks. Without treatment, most people improve slowly over several months. However, with early treatment, people can improve very quickly—in days or weeks. About 30% of adults and even more children with the disorder have residual weakness 3 years after the syndrome began. On average, fewer than 2% of people die.
Treatment
Guillain-Barré syndrome can worsen rapidly and is a medical emergency. People who develop this syndrome should be hospitalized immediately. Establishing the diagnosis is crucial because the sooner appropriate treatment is started, the better the chance of a good outcome.
In the hospital, people are closely monitored so that breathing can be assisted with a ventilator if necessary. Nurses take precautions to prevent pressure sores and injuries by providing soft mattresses and by turning the people with severe weakness every 2 hours. If weakness is less severe, physical therapy is started to help preserve joint and muscle function. Heat therapy may be used first to relieve pain and thus make physical therapy more comfortable.
Immune globulin, given early and intravenously for 5 days, is the treatment of choice. If immune globulin is ineffective, plasma exchange (filtering of toxic substances, including antibodies to the myelin sheath) from the blood—see Blood Transfusion:Special Blood Donation Procedures ) can help. These treatments are relatively safe, shorten the hospital stay, speed recover, and reduce the risk of death and permanent disability.
Corticosteroids do not help and may worsen the syndrome.
Chronic Inflammatory Demyelinating Polyneuropathy
Chronic inflammatory demyelinating polyneuropathy (chronic acquired demyelinating polyneuropathy, or chronic relapsing polyneuropathy) is a form of polyneuropathy that, like Guillain-Barré syndrome, causes increasing muscle weakness, but the weakness progresses for more than 8 weeks.
As in Guillain-Barré syndrome, nerves are damaged by an attack by the body's immune system. Weakness and abnormal sensations (numbness and a pins-and-needles sensation) progress for more than 8 weeks. Weakness can worsen continually or come and go. Reflexes are usually absent. In most people with this disorder, blood pressure fluctuates less, abnormal heart rhythms occur less often, and other internal functions are less impaired than in people with Guillain-Barré syndrome. Also, weakness may be more irregular, affecting the two sides of the body differently, and weakness may progress more slowly.
Diagnosis
Doctors suspect chronic inflammatory demyelinating polyneuropathy based on symptoms. It can be distinguished from Guillain-Barré syndrome (which causes similar symptoms) because it progresses for more than 8 weeks.
Electromyography, nerve conduction studies, and a spinal tap to obtain cerebrospinal fluid are done to confirm the diagnosis. Rarely, a biopsy of the nerve is needed.
Treatment
Corticosteroids such as prednisone can relieve symptoms. Drugs that inhibit the immune system (immunosuppressants) such as azathioprine may also be used. However, if chronic inflammatory demyelinating polyneuropathy is severe or progresses rapidly, plasma exchange or immune globulin given intravenously may be preferred to corticosteroids. People may need treatment for months or years.
Last full review/revision September 2012 by Michael Rubin, MDCM
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