Infectious polyneuritis

Alternative names

Landry-Guillain-Barre syndrome; Acute idiopathic polyneuritis; Guillain-Barre syndrome; Acute inflammatory polyneuropathy

Definition

Guillain-Barre syndrome is a disorder caused by nerve inflammation involving progressive muscle weakness or paralysis, which often follows an infectious illness.

Causes, incidence, and risk factors

Guillain-Barre syndrome is an acute type of nerve inflammation. The inflammation damages portions of the nerve cell, resulting in muscle weakness or paralysis and sensory loss. The damage usually includes loss of the myelin sheath of the nerve (demyelination), which slows the conduction of impulses through the nerve.

The damage can also cause kill the axon part of the nerve cell (denervation), which stops nerve function entirely. Without the axon, messages cannot be transferred from one nerve cell to another.

The exact cause of this disorder is unknown. It may occur at any age but is most common in people of both sexes between the ages 30 and 50. It often follows a minor infection, usually a respiratory (lung) infection or gastrointestinal (gut) infection. Frequently, signs of the original infection have disappeared before the signs of Guillain-Barre begin.

Guillain-Barre syndrome may occur in association with viral infections like mononucleosis, AIDS, and herpes simplex, or after infections with bacteria (such as mycoplasma), and some types of diarrhea. Sometimes Guillain-Barre occurs following surgery or vaccinations (such as rabies and swine flu vaccines) or in association with other medical problems such as systemic lupus erythematosus or Hodgkin's disease.

Symptoms

The disorder progresses rapidly (from days to a few weeks), causing weakness or paralysis equally on both sides of the body. As weakness starts in the legs and then spreads to the arms, it is referred to as ascending paralysis. At the same time, patients may notice tingling, foot or hand pain, and clumsiness. As paralysis worsens, the patient may require assisted ventilation in order to breathe.

The beginning phase of the illness is a rapid worsening that may take only a few hours to reach the most severe symptoms. These severe symptoms may last up to 3 weeks. This is followed by a plateau phase of no changes, then a recovery phase of improvement over days to 6 months or longer.

Typical symptoms include the following:

• Muscle weakness or paralysis (the most common symptom) or uncoordinated movements:
  o Weakness begins in the feet and legs and may progress upward to the arms and cranial (head) nerveso May progress rapidly over 24 to 72 hourso May begin in the arms and progress downwardo May occur in the arms and legs at the same timeo May occur in the cranial nerves onlyo May not occur (mild cases)