Definition and epidemiology
Guillain-Barre syndrome (GBS) is an umbrella term for acute immune-mediated polyneuropathies, but in the Western world AIDP is the most common form, so it’s almost synonymous with GBS. Patients with AIDP have progressive weakness of the limbs over a few days to 28 days, symmetrical deficit, areflexia, absent or mild sensory disturbance, elevated cerebrospinal fluid protein, and slowing of nerve conduction velocities.
- Acute inflammatory demyelinating polyradiculoneuropathy (AIDP)
- Miller Fisher syndrome (MFS)
- Acute motor axonal neuropathy
- Acute sensorimotor axonal neuropathy (AMSAN)
The disorder may be preceded by upper respiratory or gastrointestinal infection 1 to 4 weeks before the onset of the symptoms.
Immune reaction against an earlier infection forms antibodies which, due to molecular mimicry, target antigens on Schwann cells, causing demyelination.
The characteristic symptoms are those of a rapidly progressing polyneuropathy, including progressive, symmetrical, flaccid, ascending muscle weakness and absence of reflexes. Sensory and autonomic symptoms may sometimes occur. The symptoms progress over 2 – 4 weeks.
Bilateral facial palsy may be present. 10 – 30% develop severe respiratory muscle weakness.
Diagnosis and evaluation
The diagnosis is based on typical clinical features, CSF studies, and ENG. CSF studies show albuminocytologic dissociation (high protein, normal cells), and ENG shows demyelination (slow conduction).
All patients should be admitted for monitoring, as respiratory failure can develop in many and these patients need ventilation. Treatment is with plasma exchange or IVIG. Steroids are not used.
7A. Carpal tunnel-syndrome