Chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyneuropathy (CVD) — a rare disease of peripheral nerves, characterized by the gradual development of weakness, impaired sensitivity in the arms and legs.

The average prevalence of patients with CVD in the world averages 1-9 per 100,000 people. The disease can begin at any age and is more common in men than in women.

Mechanisms of disease development

The mechanisms of CVD development are not fully understood. However, it is known that the disease is autoimmune. That is, the body's immune system, which normally protects the body, perceives myelin as a foreign object and attacks it.

Myelin is an important part of the peripheral nervous system. It forms the sheath of a nerve fiber, wrapping around an axon (part of a nerve cell) in the same way as insulation around an electrical wire. Nerves run from the spinal cord to the rest of the body, stimulating muscle contraction and transmitting sensory information to the nervous system from receptors in the skin and joints. This insulation (myelin) allows electrical impulses to pass efficiently along the nerve axon. When myelin is damaged, electrical impulses slow down and messages transmitted from the brain are interrupted.

Clinical manifestations

The diagnosis of a typical form of CVD is based on the following symptoms:

Impaired sensitivity (numbness, tingling in the hands and feet), weakness (difficulty walking), developing for more than 8 weeks and lack of reflexes.

However, the symptoms and nature of the course of the disease may vary. Currently, it is customary to distinguish CVD variants that differ from the typical course of the disease. Such forms include:

• Distal form of CVD
• Multifocal form of CVD (Lewis-Sumner syndrome)
• The focal shape of the HVDP
• Motor form of HVDP
• The sensory form of HVDP

Instrumental diagnostic studies are required to establish the diagnosis:

• Stimulation electroneuromyography (ENMG) to determine the nature of damage to the peripheral nervous system. ENMG allows you to evaluate the conductivity of peripheral nerves using electrical stimulation, which is transmitted along the nerve and leads to contraction of the muscle innervated by the nerve under study, which is recorded by the electrode. 

• Ultrasound examination of peripheral nerves allows us to establish a change in the structure of the nerve and an increase in the cross-sectional area, which indicates in favor of demyelinating polyneuropathy (myelin damage).

Ultrasound of the median nerve on the forearm in a patient with CVD (Figure 3), normal (Figure 4).

• MRI of the nerve plexuses allows you to detect thickening of the plexus trunks and accumulation of contrast.
• Examination of cerebrospinal fluid (CSF). In some patients with CVD, there is an increase in protein in CSF, but not as pronounced as, for example, in Guillain-Barre syndrome
• In rare cases, analysis for specific antibodies (anti-NF155, anti-CNTN1, anti-Caspr1) and nerve biopsies are required.

Therapy

Most patients with CVD note the effect of immunomodulatory therapy. Currently, there are recommendations for the treatment of CVD. Large randomized trials were conducted to confirm the effectiveness of the following groups of drugs:

• Glucocorticosteroids
• High doses of intravenous immunoglobulins
• Plasmapheresis

There are a large number of second-line drugs used to treat CVD. They are used when the above standard treatments are ineffective, cause significant side effects, or the clinical response is not optimal. The effectiveness of these drugs is mainly confirmed by a series of clinical cases from medical publications.

Each of the methods of treatment has its advantages and disadvantages in the form of possible side effects. That is why the advice of an experienced specialist is necessary.

If you have symptoms of polyneuropathy or have previously been diagnosed with "CVD", you can consult the Center for Neuromuscular Pathology MCSC named after A.S. Loginov.

On the basis of the neurological department during hospitalization, it is possible to conduct a comprehensive examination that will help identify the cause of nerve damage, clarify the diagnosis, and also begin therapy based on the latest research data.

Make an appointment for a consultation at the Central Medical Center : +7 (495) 304-30-39