This is the most common demyelinating neuropathy in Europe, North America and other developed countries. In this form of GBS the immune attack is directed against the myelin causing loss of the myelin sheath and leading to a “short circuit” so that electrical messages cannot travel between the brain and the periphery of the body rarely axon damage can also occur with AIDP. AIDP causes acute weakness of limb and breathing muscles and sensory symptoms such as numbness and tingling.
In this form of GBS the primary immune-mediated attack is against the nerve axon itself causing the electrical cable to degenerate. It does occur in developed countries but is uncommon. With AMAN the attack is limited to the axons that control muscle activity and causes only weakness of limb and breathing muscles with no involvement of sensation
In this form of GBS the attack on the axons affects both sensory and motor functions and is probably a more sever form of AMAN. It is commonly seen as summer outbreaks in northern rural China. When there us extensive axonal degeneration recovery is slower and there is a greater likelihood of some residual weakness.
This form of GBS causes paralysis of the eye muscles (ophthalmoplegia) and loss of balance and co-ordination (ataxia) and loss of reflexes (areflexia) although the primary site of the immune attack damage is uncertain
This like CIDP is a chronic condition but differs from it in two important aspects. Firstly, the damage is restricted to the motor axons so patients have the weakness but no numbness, tingling or pain and secondly the demyelination is very patchy affecting nerves in a seemingly random pattern. The symptoms develop very slowly and usually progress over many years and patients may be unaware of muscle weakness in some areas and only seek medical advice when important functions, such as hand function, are affected.