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The estimated annual incidence of Guillain-Barre Syndrome is approximately 0.4 to 1.7 cases per 100,000 population. There is considerable variation in the reported incidence in children. In one large study from a developing country, the overall incidence was 1.1/100,000 population. However, the incidence for children younger than 4 years of age was 1.7/100,000 compared with 0.1/100,000 for children older than 10 years of age. On the other hand, a study from Finland reported an incidence of 0.38/100,000 for children younger than 15 years of age, with no differences between older or younger children. The disease is very rare in children younger than 1 year of age. There is an approximately 1.5:1 male- to-female ratio. Male predominance is more significant in adults, particularly the elderly.
The acquired nature of the disease, the response to immunologic therapy, and the pathology all suggest that Guillain-Barre Syndrome is an immune-mediated disease. However, the precise mechanism of the immunologic injury is unclear. Recently it has been shown that a previous gastrointestinal infection with Campylobacter jejuni is associated with a more severe form.
The pathologic features of Guillain-Barre Syndrome are distinct. There are multifocal areas of inflammation and demyelination with cellular infiltration of macrophages and lymphocytes (Figs. 1 and 2). The inflammatory response is more severe at the junction of the dorsal and ventral roots at the site of the dural attachment. In the demyelinating form of the disease, macrophages penetrate.
Approximately 50% to 70% of patients who have Guillain-Barre Syndrome have a history of an antecedent illness within the previous 4 weeks. Often this illness is an upper respiratory disease or gastroenteritis. Specific agents that have been implicated include cytomegalovirus, Epstein-Barr virus, and Campylobacter jejuni. C jejuni is the most common cause of a diarrheal illness.
A diagnosis of Guillain-Barre Syndrome is based on characteristic clinical features, electrodiagnostic studies, and a few laboratory tests (Table 1). The major clinical features are progressive muscle weakness and diminished deep tendon reflexes with symmetric distribution.
Although weakness is the hallmark of the disease, sensory disturbances also are quite common. Approximately 40% of patients will complain of pain or paresthesias in the extremities, around the mouth, or in the back as the presenting symptom. Pain in a band distribution is common.
Other clinical features that are less constant include cranial nerve involvement with facial weakness, difficulty in swallowing, and occasionally, involvement of the cranial nerves that control ocular motility. Approximately 15% to 20% of patients progress to respiratory failure.
Guillain-Barre Syndrome has three stages. There is a progression phase over several days to several weeks, a plateau phase of similar duration, and then recovery over weeks to months.
The most important electrodiagnostic feature in Guillain-Barre Syndrome is evidence of multifocal demyelination in motor and sensory nerves. The sensory nerve responses are variable, with reduced amplitudes and prolonged latencies. The motor responses often show a reduction in the compound muscle action potential (CMAP) as a result of distal demyelination and, rarely, from loss of axons. A severe reduction to less than 10% of normal is considered a very poor prognostic sign.
Several other acquired peripheral nervous system diseases have similar temporal and clinical profiles and are considered to be variants of Guillain-Barre Syndrome. They are less common in children than in adults.
Acute motor axonal neuropathy (AMAN syndrome) is a particularly severe form of Guillain-Barre Syndrome and more often is associated with preceding C jejuni infection. The axonal injury causes
The mainstay of treatment is supportive care. The most common causes for death are autonomic.
Plasma exchange has been shown to reduce significantly the number of days in the intensive care unit, the number of days on the ventilator, and the number of total days in the hospital. The recommended protocol is 250 mL/kg body weight of plasma divided into four to six sessions during the first week of the illness. It does not appear to make much difference whether albumin or fresh frozen plasma is used as a replacement volume. Both the cell separation and filtration membrane techniques are effective. Protein A immunoabsorption also has been shown to be effective by selectively removing immunoglobulins from the
More recently, intravenous immune globulin (IVIG) therapy has been shown to alter the course of the disease favorably. Studies in both adults and children have shown the efficacy to be similar to that of plasma exchange. Because IVIG is widely available, it is perhaps the preferred treatment of choice.