Guillain–Barré syndrome

Guillain–Barré syndrome (GBS) is a rapid-onset muscle weakness as a result of damage to the peripheral nervous system. Many experience changes in sensation or develop pain, followed by muscle weakness beginning in the feet and hands. The symptoms develop over half a day to two weeks. During the acute phase, the disorder can be life-threatening with about a quarter developing weakness of the breathing muscles and requiring mechanical ventilation. Some are affected by changes in the function of the autonomic nervous system, which can lead to dangerous abnormalities in heart rate and blood pressure.

This autoimmune disease is caused by the body's immune system mistakenly attacking the peripheral nerves and damaging their myelin insulation. Sometimes this immune dysfunction is triggered by an infection. The diagnosis is usually made based on the signs and symptoms, through the exclusion of alternative causes, and supported by tests such as nerve conduction studies and examination of the cerebrospinal fluid. Various classifications exist, depending on the areas of weakness, results of nerve conduction studies, and the presence of antiganglioside antibodies. It is classified as an acute polyneuropathy.