Guillain-Barré Syndrome
An acute, rapidly progressive, and potentially fatal form of polyneuritis, Guillain-Barré syndrome causes segmented demyelination of peripheral nerves. The syndrome occurs equally in both sexes, usually between ages 30 and 50. It affects about 2 of every 100,000 people.
The clinical course of Guillain-Barré syndrome has three phases. The acute phase begins when the first definitive
symptom develops; it ends 1 to 3 weeks later, when no further deterioration is noted. The plateau phase lasts for several days to 2 weeks and is followed by the recovery phase, which is believed to coincide with remyelination and axonal process regrowth. The recovery phase extends over 4 to 6 months; however, patients with severe disease may take 2 to 3 years to recover. Furthermore, recovery may not be complete. The syndrome is also known as infectious polyneuritis, Landry’s syndrome, or acute idiopathic polyneuritis.
symptom develops; it ends 1 to 3 weeks later, when no further deterioration is noted. The plateau phase lasts for several days to 2 weeks and is followed by the recovery phase, which is believed to coincide with remyelination and axonal process regrowth. The recovery phase extends over 4 to 6 months; however, patients with severe disease may take 2 to 3 years to recover. Furthermore, recovery may not be complete. The syndrome is also known as infectious polyneuritis, Landry’s syndrome, or acute idiopathic polyneuritis.
Causes
The precise cause of Guillain-Barré syndrome is unknown, but it’s believed to be a cell-mediated immunologic attack on peripheral nerves in response to a virus. Risk factors include surgery, rabies or swine influenza vaccination, viral illness, Hodgkin’s or some other malignant disease, and systemic lupus erythematosus.
The major pathologic effect is segmental demyelination of the peripheral nerves that prevents normal transmission of electrical impulses along the sensorimotor nerve roots.
Complications
The patient’s inability to use his muscles may lead to such complications as thrombophlebitis, pressure ulcers, contractures, muscle wasting, aspiration, respiratory tract infections, and life-threatening respiratory and cardiac compromise.
Assessment
Most patients seek treatment when the syndrome is in the acute stage. The patient’s history typically reveals a minor febrile illness (usually an upper respiratory tract infection or, less often, GI infection) 1 to 4 weeks before his current symptoms.
The patient may report feelings of tingling and numbness (paresthesia) in the legs. If the syndrome has progressed further, he may report that the tingling and numbness began in the legs and progressed to the arms, the trunk and, finally, the face. The paresthesia usually precedes muscle weakness but tends to vanish quickly; in some patients, it may never occur. The patient may also report stiffness and pain in the calves, such as a severe charley horse, and in the back.
Neurologic examination uncovers muscle weakness (the major neurologic sign) and sensory loss, usually in the legs. If the syndrome has progressed, the weakness and sensory loss may also be present in the arms. Keep in mind that the syndrome progresses rapidly and that symptoms may progress beyond the legs in 24 to 72 hours.
If the cranial nerves are affected—as they often are—the patient may have difficulty talking, chewing, and swallowing. Subsequent cranial nerve testing may reveal paralysis of the ocular, facial, and oropharyngeal muscles. Neurologic examination may reveal loss of position sense and diminished or absent deep tendon reflexes.
Remember that muscle weakness sometimes develops in the arms first (descending type) rather than in the legs (ascending type), or in the arms and legs simultaneously. Remember, too, that in milder forms of the syndrome, muscle weakness may affect only the cranial nerves or may not occur at all.
Diagnostic tests
Cerebrospinal fluid (CSF) analysis may show a normal white blood cell count, an elevated protein count and, in severe disease, increased CSF pressure. The CSF protein level begins to rise several days after the onset of signs and symptoms, peaking in 4 to 6 weeks, probably resulting from widespread inflammatory disease of the nerve roots.
