sections include: what causes Guillain-Barré syndrome?, treating GBS
Guillain-Barré syndrome (GBS) is an autoimmune disease of the peripheral nerves that causes weakness in the limbs and other body parts. It can be triggered by something as common and inescapable as a cold virus. Now that polio has been eradicated in developed countries, GBS has become the most common cause of general paralysis. Fortunately, the condition improves on its own or with treatment in most cases.
The illness usually begins with a feeling of pins and needles (paresthesias) in the feet and hands and with weakness of the legs. Both of these signs worsen over several days. Some people also suffer weakness of the facial muscles, similar to Bell’s palsy. GBS symptoms, both sensory and motor, characteristically affect both sides of the body more or less equally, which is quite different from the paralysis and sensory loss of a stroke. As the illness worsens, weakness can become quite severe; most people who contract GBS are unable to walk within a week or so. About one in four will eventually have weakness of the muscles of breathing, which of course is very serious. There are many variations on this pattern, and some people experience other symptoms of GBS: double vision (diplopia), severe clumsiness of walking and limb movement (ataxia), severe weakness without changes in sensation, trouble swallowing, and so on. One particular constellation of problems is double vision and clumsiness, called Miller Fisher syndrome. Some people suffer rapid worsening over one or two days instead of several. GBS does not affect the mind, however; only the nerves in the arms, legs, and facial areas are involved.
In most instances the weakness worsens for several days, or up to two or three weeks, until the person’s condition levels off. The severity of the weakness at this point is highly variable. A fraction of people with GBS—fewer than 10 percent—are still able to walk. Most are bed-bound at the disease’s worst point. Some are almost completely paralyzed and need a respirator to keep breathing. The last group must be cared for in a hospital’s intensive care unit. Being on a respirator means a patient must have a tube inserted in his or her trachea, which prevents speaking and eating, so the hospital must supply other means of communication and feeding. Many other problems occur in people severely affected by GBS because of their weakness and immobilization; pneumonia, urinary infections, and blood clots in the legs and lungs are the most frequent. A few people have an unusual problem with their autonomic nervous system that causes their blood pressure and pulse to fluctuate greatly; this, too, requires special treatment.
What Causes Guillain-Barré Syndrome?
Throughout the world GBS occurs in about 2 people per 100,000 each year. Among these patients there is a very slight predominance of women, but the disease has no age, ethnic, regional, or seasonal predilection. Inheritance is not thought to be a factor; the cases in which different family members have contracted the illness have been very infrequent. There are no known ways to prevent GBS, but fortunately there are no signs that it is contagious.
More than one third of GBS cases begin some days after an infection with fever. The triggering infection is most commonly a cold or flulike illness, but it can also show up as diarrhea or other problems. Because people are often still getting over the fatigue and overall poor feeling of these illnesses, they sometimes attribute the GBS symptoms in their fingers and toes to the infections. Of the many people who suffer a particular infection in any given period, however, only a few—or none—will develop GBS. And in one-third of GBS cases, the individual and his or her doctors can identify no triggering infection.
In rare cases, GBS follows vaccinations of various sorts. Because of that slightly increased incidence, some have questioned the safety of administering vaccinations to people who have developed the condition before. After much discussion in the field, most doctors have decided in favor of giving vaccinations to those individuals who may be at risk of contracting the flu because the chances of serious complications from influenza are still far greater than the chance of contracting GBS from the immunization.
From these and other indications, we have come to recognize GBS as a temporary autoimmune disease. An infection or other challenge to a person’s immune system leads his or her white blood cells to produce an immune protein that attaches to and damages the nerves. For instance, there is strong evidence that the body produces antibodies to fight off the diarrhea-causing bacterium Campylobacter; the antibodies then also react to the person’s nerves. Other infections that often precede GBS are mononucleosis from the Epstein-Barr virus, pneumonia from mycoplasma bacteria, HIV infection, and hepatitis due to cytomegalovirus. In many cases an individual may not notice the infection, even as a low-grade fever, but his or her immune system still reacts. The misdirected immune attack usually strikes the cylinder of fatty material, myelin, that surrounds nerve fibers—a process called demyelination. In about 10 percent of cases the nerve fiber itself (the axon) is the site of the main damage. And many people with GBS have a combination of these two types.
GBS is fairly easy for doctors to identify from a person’s description of his or her symptoms and a neurological examination. They can establish the diagnosis with more certainty through electrical testing of the nerves (electromyogram) and sampling the spinal fluid to see if it shows an increase in the amount of protein. Cases with unusual features may be more difficult to diagnose. Neurologists usually direct the care of people with GBS. If major medical problems arise, or if respiratory failure requires the use of a ventilator, a specialist in intensive care, pulmonary medicine, or anesthesia usually becomes involved as well. Several treatments seem to shorten the course of GBS, but they are not cures and they do not seem to influence the disease’s course in all individuals. The first therapy shown to be effective was plasma exchange. This process starts with removing some of the patient’s blood and spinning it in a centrifuge machine in order to separate the plasma from the blood cells. Only the cells are returned to the patient’s body, with the missing plasma replaced by an artificial fluid. In this procedure, a tube must be placed in one of the large veins of the chest or neck to bring enough blood to the centrifuge machine.
Several treatments are performed over a week or two, each taking about two hours. The main risks have to do with injury to the lung from the tube. Most patients tolerate the treatment well, but some experience low blood pressure, fatigue, and tingling from time to time.
A newer and easier alternative is administering intravenous immunoglobulin (IVIG), several bottles daily for four or five days. The IVIG is obtained from the blood donations of many individuals, screened for viruses; the risk of contracting an illness from this procedure is extremely low. As with plasma exchange, improvement is usually not apparent immediately after treatment. Nevertheless, most studies have shown that these therapies cut in half the time it takes for a person to walk again. Certain patients are less likely to improve—for example, those with severe damage to the nerve fibers (axonal GBS).
A person with GBS is typically hospitalized for one to several weeks, during which he or she experiences slow improvement. The person then goes to a rehabilitation hospital or is discharged home with physical therapy visits. More severe cases—people who have been on a ventilator or have been virtually paralyzed—require months in the hospital and various types of rehabilitation afterward. Almost no people who develop GBS stay on a ventilator for the rest of their lives, but about 5 percent remain so weak that they need canes and braces or a wheelchair for years or indefinitely.
Improvement may continue in the most severely affected people for about two years. After that time it is still possible to make gains, but they are largely the result of overtraining of muscles with physical therapy and assistive devices. That is, improvement is not due to recovery from the neuropathy but to increased physical stamina and strength as a result of the exercise. Older people, particularly over 70, and those with severe damage to the axons are more at risk for having a long and probably incomplete recovery, but some patients in these categories have done well. Although medical teams have used many forms of rehabilitative therapy, no one program has proven superior overall; treatments must be tailored to the individual’s pattern of weakness. Vitamins, health-food supplements, acupuncture, electrical stimulation, and other alternative treatments have not proven to be of any benefit.
back to top