Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare neurological disorder that causes inflammation of the body’s nerves. Though the immune system generally keeps a person healthy by fighting off germs, with CIDP, the immune system does not recognize parts of the nerves and attacks them.

Specifically, the immune system mistakenly attacks the nerves’ protective myelin. When the myelin is damaged or removed, messages transmitted to and from the brain are disrupted and may never make it to their final destination. It’s not known what causes CIDP. While CIDP is often associated with Guillain-Barre Syndrome (GBS), GBS is a short-term illness linked to an illness while CIDP can be more long-term and isn’t known to be tied to an illness. It’s also not clear if CIDP is a hereditary condition.

There are three different types of CIDP: monophasic, recurrent, and progressive. Monophasic CIDP refers to a case of CIDP which lasts for 1-3 years and never recurs. Recurrent CIDP is when symptoms are present intermittently. Progressive CIDP is when symptoms become progressively worse over time.