Chronic inflammatory demyelinating polyneuropathy is a neurological disease that damages and destroys the nerves in a person's body.
The condition, which is abbreviated to CIDP, affects a person's ability to move, especially their arms and legs, as well as their sensory functions, leading to tingling and numbness.
The disorder is rare, occurring in around 5 to 7 people per 100,000 people in the United States, according to the National Organization for Rare Disorders.
Fast facts on CIDP:
- The average age of onset of the disease is 50 years old.
- Men are twice as likely as women to experience it.
- Symptoms may start with a change in walking or tingling and numbness in the hands and feet.
Although doctors do not know the exact cause of CIDP, they believe the condition is an autoimmune disorder where the body's defense systems attack healthy tissues.
In the case of CIDP, these healthy tissues are the myelin sheaths that protect nerves and enable the nervous system to transmit signals more quickly.
The condition also causes inflammation in the nerves.
Difference to other disorders
While the disease has some similarities to other neurological disorders, such as Guillain-Barre syndrome (GBS) and multiple sclerosis (MS), there are several differences in onset, symptoms, and treatments.
For example, a person with GBS can often identify an infection that occurred before their symptoms began, such as mononucleosis. Those with CIDP cannot usually recall a preceding infection.
A person with CIDP usually has symptoms that may continue for about 8 weeks, or twice as long as the duration of typical GBS symptoms.
Another difference is that GBS is an acute disorder that will not typically recur while CIDP symptoms may be ongoing. Some doctors consider CIDP a chronic form of GBS.
Symptoms associated with CIPD tend to be progressive. Some of the condition's potential symptoms include:
- dysphagia or difficulty swallowing
- double vision
- foot drop
- loss of reflexes
- numbness in the hands or feet
- tingling or pain in the extremities
- unexplained fatigue
The condition's symptoms tend to occur on both sides of the body, for example, in both legs. Some people may only notice changes in sensory function, such as tingling and numbness, without experiencing changes in their walking or movement.
Treatment for CIDP involves trying to reduce the inflammation that causes the nerve-related symptoms.
Although there is no cure for the condition, medications that modulate or normalize the immune system can help improve the effects CIDP has on a person's nerves. The U.S. Food and Drug Administration (FDA) recently approved two drugs to treat CIDP.
The selected drugs decrease the immune system activity that causes nerve-related symptoms.
Both are in the IVIg (intravenous immunoglobulin) class.
One of these drugs is Gamunex, and the other is Privigen. Both drugs contain antibodies (immunoglobulins) that help prevent other immunoglobulins from damaging nerves.
While these medications can help to reduce inflammation in CIDP, they do not cure it.
A doctor may also prescribe medications called immunomodulators that are known to suppress the immune system and improve signs and symptoms of CIDP.
These drugs include:
Another effective option to treat CIDP is plasma exchange or plasmapheresis.
This procedure involves removing blood from an individual and separating the red blood cells and components, such as antibodies, from the plasma that contributes to CIDP. Donor plasma is then added to the blood, which is transfused back into the individual.
Some medicines can help the symptoms of CIDP without modulating the immune system or decreasing inflammation.
These drugs can be given alongside the immunomodulators mentioned above. They include:
CIDP is a rare condition, so doctors may have difficulty in diagnosing it initially.
Because the symptoms are often progressive, a doctor may need to monitor an individual over the course of 1 to 2 months before being clear about the diagnosis.
A doctor will begin by taking a medical history and asking the person about symptoms. Some signs that may indicate CIDP include the absence of reflexes and weakness in the arms and legs.
After considering a person's symptoms, a doctor will likely order a range of tests to rule out other similar disorders. For example, they may recommend a lumbar puncture to test spinal fluid for the presence of inflammatory cells, such as white blood cells. Meningitis and nervous system cancer can also cause a range of symptoms that are similar to CIDP.
A doctor may also order tests to measure how well a person's nerves are conducting electrical signals. These tests include nerve conduction testing and electromyography.
If a person's nerves are not conducting as quickly as expected, this could support a diagnosis of CIDP.
People respond differently to CIDP treatments. Some may see an improvement in immune system function, others may see many of their symptoms resolve, but some may not have any improvement.
Sometimes doctors will recommend an anti-inflammatory diet for those with CIDP to help reduce their symptoms. However, diet is no substitute for the medications listed above.
An anti-inflammatory diet has many of the same characteristics as most healthful diets, so a person should avoid:
- high-sodium foods
- high-sugar foods
- processed foods
- saturated fats
- trans fats
A person with CIDP should eat a predominantly plant-based diet filled with colorful fruits and vegetables. Other foods someone with CIDP should eat, include lean meats and fatty, low mercury fish, such as salmon.
Dietary recommendations may vary according to an individual's additional health conditions or unique dietary preferences.
Those treated for CIDP often experience an improvement in symptoms, then a series of relapses.
According to a study published in the journal Current Treatment Options in Neurology, an estimated 90 percent of people with CIDP will respond to immunosuppressive treatments, such as IVIg.
However, in the long-term, many people with CIDP eventually require assistive devices, such as canes, walkers, or wheelchairs to help them move around.
As a general rule, the earlier a person is diagnosed and treated for CIDP, the better their prognosis tends to be.