Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare neurological disorder in which there is inflammation of nerve roots and peripheral nerves and destruction of the fatty protective covering (myelin sheath) of the nerve fibres. Myelin allows nerve fibres to transmit signals very rapidly (40-60 meters/second). Loss or damage to myelin can cause slowing or blockage of the nerve signals and can lead to loss of nerve fibres. This causes weakness, paralysis and/or impairment in motor function, especially of the arms and legs. The sensory disturbance may also be present. The motor and sensory impairments usually affect both sides of the body (symmetrical), and the degree of severity and the course of the disease may vary from person to person. Some affected individuals may follow a slow steady pattern of symptoms while others may have symptoms that stabilize and then relapse.

Middle-aged woman suffering from pain in leg at home, closeup. Physical injury concept. Ankle pain, painful point.

A syndrome is not a single disease

Typical CIDP and Variants
CIDP has a number of clinical presentations. Typical CIDP is defined as an asymmetric motor and sensory disorder that has a proximal and distal weakness (including muscles of the shoulders and hips as well as the hands and feet). Deep tendon reflexes are absent.

Variants of CIDP include:

  1. A multifocal variant in which the deficits are asymmetric and may involve different individual nerves. This form has been called Lewis-Sumner syndrome or MADSAM (multifocal acquired demyelinating sensory and motor).
  2. Pure sensory variants in which patients have imbalance and incoordination but no demonstrable muscle weakness.
  3. A distal variant in which the sensory and motor deficits do not involve the proximal arms and legs.
  4. A pure motor variant in which no sensory abnormality is found.

The fact that there are different forms of CIDP points to the fact that at this time, CIDP is a syndrome and that there may be a number of different causes of the disorder which manifest in different ways.


There are a number of treatments available to control CIDP. The best-studied treatments that have been shown to be effective are glucocorticoids (steroids), intravenous immunoglobulin (IVIg) and plasma exchange (PLEx). All the treatments suppress or modulate the immune system and there are increased risks of infection and cancer that must be considered when treatment decisions are being made.