CIDP

What is CIDP?

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare immune-mediated disorder that can cause severe limitations to a patients’ daily life. Over the course of several months, patients usually experience progressive muscle weakness and sensory disturbances, such as numbness or tingling, in the arms and legs.

If left untreated, patients can become unable to walk and might lose their independence in daily activities. In the Netherlands, approximately 50 people are diagnosed with CIDP each year. CIDP affects both children and adults but is more common in adults.

Cause

The exact cause of CIDP is unknown. The current understanding is that a patients’ immune system attacks the insulating covering of the peripheral nerves: the myelin sheet. The inflammatory process hampers the signal conduction from the brain to the muscle, leading to a decreased muscle function.

Fortunately, patients can regain their muscle function through treatment that selectively inhibits the immune system, combined with a rehabilitation programme. The extent to which patients regain muscle function varies. The potential to reverse the detrimental process is thought to be associated with the duration of symptoms before treatment is initiated.

When CIDP is recognized early, the chance of recovery is better. However, due to its rarity and diagnostic complexity diagnosis is often delayed. Therefore, it is important to create awareness, and identify factors that help to recognize patients with CIDP.

Diagnosis

There is no biomarker available to diagnose CIDP, so physicians need to recognize the pattern of clinical symptoms combined with results from additional testing. Recognizing CIDP is difficult, because there is a large variation in the presentation of symptoms. Different variants of CIDP exist, each with a specific distribution of muscle weakness and/or sensory disturbances.

• The majority, about 50%, of patients have a typical course of CIDP, in which muscle weakness and sensory disturbances in arms and legs progress over a period of at least two months.
• The other 50% of patients have one of several CIDP variants, such as muscle weakness without sensory disturbances (pure motor CIDP) or sensory disturbances without muscle weakness (pure sensory CIDP). An asymmetrical (‘spotty’) distribution of muscle weakness and sensory disturbances is called multifocal CIDP (MADSAM).

Medical treatment

CIDP is a treatable disorder, but some patients do not improve with treatment or improve only to a limited extent. It is therefore necessary to evaluate for each patient individually whether treatment is useful, and which treatment is best suited.

After diagnosis, treatment is often initiated with either corticosteroids (tablets or infusions) or infusions with immunoglobulins (IVIg), which are antibodies from donor plasma. Both treatments selectively inhibit the response of the patients’ immune system, reducing the inflammation of the nerves.

Most patients diagnosed with CIDP improve after initiation of medical treatment. Currently, physicians are unable to predict which treatment will give individual patients the best chance of recovery.