Guillain-Barre Syndrome

Guillain-Barre Syndrome (GBS), also known as acute inflammatory demyelinating polyneuropathy, is an autoimmune disease whereby antibodies mistake the myelin sheath for pathogens. This results in demyelination of the peripheral nerves and nerve roots leading to muscle weakness. It commonly follows a respiratory tract or gastric infection, or perhaps from immunisation or surgery. In order to be classified as GBS, the time of onset to peak disability (nadir, meaning opposite or lowest point in fortunes) should be less than 4 weeks. 

Muscle Weakness

·  Leg weakness if often noted first, progresses proximally and includes all muscle groups

·  Asbury & Corblath (1990) discovered that 50% of pts reach nadir in two weeks

·  Nadir can include complete paralysis, and 50% of pts have facial weakness

·  Frequently bulbar muscle groups are affected to require NG feeding to avoid aspiration

·  Paralysis of respiratory muscles causes vital capacity to fall in 30% of pts, where elective ventilation is indicated

GBS is predominantly a motor neuropathy, but 42-75% of pts have some alteration in sensation. Joint positional sense in the toes is missing in over 50% of pts. It has been postulated that pain could be due to inflamed and tightened neural structures in the acute stage, however could be due to abnormal forces on joints that are poorly protected by weakened muscles.

Recovery tends to occur within a month of nadir, and has the potential to be complete providing secondary implications such as contractures are avoided.