Chronic inflammatory demyelinating polyneuropathy (CIDP)

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disorder in which the immune system attacks the peripheral nerves. These are the nerves outside the brain and spinal cord, including the nerve roots where they leave the spine. The main target is myelin, the fatty coating that helps nerve signals travel quickly, so signals slow down or get blocked.

CIDP develops over at least eight weeks, and it may keep getting worse or come and go. This helps doctors tell it apart from Guillain-Barré syndrome, a related condition that reaches its worst within about four weeks. The typical form affects both sides of the body evenly, while other forms may mainly affect the hands and feet, affect the two sides unevenly or only one area, or affect only movement or only feeling.

CIDP is acquired, which means people are not born with it. In many people, no cause can be found, and in most, doctors do not know exactly which part of the nerve the immune system is targeting. Both immune cells and antibodies seem to be involved.

CIDP is rare. It is slightly more common in men than in women. It can happen at any age, but the US Food and Drug Administration says people in their 50s and 60s seem more likely to get it.

Some people who might once have been told they had CIDP are now known to have a separate condition called autoimmune nodopathy. It is caused by specific antibodies against parts of the nerve, is found with a blood test and can respond differently to treatment.

Typical CIDP causes weakness in muscles close to the body, such as the hips and shoulders, and farther out, such as the hands and feet. People may have trouble climbing stairs, getting up from a chair, gripping things or walking. Numbness, tingling, poor balance and weak or missing reflexes are common, and some people also have pain or deep tiredness.

Diagnosis relies on a neurologic exam and nerve conduction studies, which measure how fast signals move along nerves. Doctors may also test spinal fluid, use scans of the nerves such as MRI or ultrasound, and check blood and urine for an abnormal protein, because several other conditions can look like CIDP. Damage to the nerve fibers themselves, called axons, has been linked to a poorer response to treatment.

CIDP is often long-lasting, and many people need treatment for years. Regular checks of strength and daily function help the care team adjust doses or try to lower them. In two large studies, nearly everyone who improved with immunoglobulin did so within 6 to 8 weeks of starting it.

Weakness and numbness can affect walking, work and everyday tasks. Tiredness and pain can also be part of living with CIDP. Patient groups offer information and connect people with others who have it.

For the few people considered for a transplant, stem cells are collected first. Strong chemotherapy and antibody treatment then wipe out much of the immune system, followed by a long recovery with a high risk of infection. Whatever the treatment, some people are left with lasting weakness or numbness, because nerve damage that has already happened may not fully heal.

CIDP is not usually treated with a donor transplant. When a stem cell transplant is used, it is autologous, which means the person’s own stem cells are collected, stored and given back after treatment. No registry donor is involved, and no donor search is needed.

In their 2025 recommendations for adults, European transplant experts (EBMT) said an own-cell transplant can be considered for carefully selected people with CIDP after careful weighing of risks and benefits. They listed donor transplants for CIDP as generally not recommended. For people living with CIDP, joining a donor registry is a way to help other patients rather than a need of their own.