Diffuse axonal brain injury

Peripheral neuropathy ( nerve neuropathy ) refers to damage to the peripheral nervous system, the extensive system of communication nerve fibers that carries information from the brain and spinal cord to any part of the body. Peripheral nerves also send sensory information back to the brain and spinal cord, informing about the presence of tissue effects (cold or burn). When the peripheral nervous system is damaged, these vital connections are disrupted.

This can be compared to a communication breakdown at a telephone exchange, when the connection between the station and the subscribers is disrupted (similar interruptions in communication occur between the brain and parts of the body). Because each peripheral nerve has a highly specialized function in a specific part of the body, when a nerve is damaged, symptoms may vary. For some, this may include numbness, tingling, excessive sensitivity to touch (paresthesia), or muscle weakness. Others may have more severe symptoms, including severe pain (especially at night), muscle wasting, paralysis, or glandular tissue or organ dysfunction. People may experience an inability to digest food normally, maintain normal blood pressure, sweating, and reproductive problems. In the most severe cases, there may be respiratory dysfunction or organ failure. In some forms of neuropathy, only one nerve is damaged, and this damage is called mononeuropathies. When a large number of nerves affecting the limbs are affected, such damage is called polyneuropathy. Sometimes two or more separate nerves in certain areas of the body are affected, this is called multifocal mononeuritis. In acute neuropathies, such as Guillain-Barré syndrome, symptoms appear suddenly, progress rapidly, and recovery of function occurs slowly as nerve fiber damage occurs. In chronic forms of neuropathy, symptoms appear gradually and progress slowly. In some patients, periods of remission are followed by periods of exacerbation. For others, the condition may reach a plateau in which symptoms remain unchanged for many months or years. Some chronic neuropathies progress over time, but very few forms are fatal unless there are complications associated with other diseases. Often, neuropathy is a symptom of another disease.

In the most common forms of polyneuropathy, the nerve fibers furthest from the brain begin to dysfunction first. Pain and other symptoms often appear symmetrically, such as in both legs, followed by gradual progression in both legs. Sometimes the fingers and arms are affected, progressing higher towards the middle of the body. Many patients with diabetic neuropathy experience this type of progression and nerve damage.

What is axonal polyneuropathy

Polyneuropathy (also known as polyneuritis) is a clinical syndrome that occurs due to a number of factors affecting the peripheral nervous system and is characterized by vague pathogenetic changes. The disease occupies one of the leading places in the list of ailments of the peripheral nervous system, second only to vertebrogenic pathology, which is superior in the complexity of the clinical picture and the consequences that develop because of it.

Asconal polyneuropathy is considered an interdisciplinary problem; doctors of various specializations often encounter it. First of all, people with this disease contact a neurologist. The frequency of the syndrome occurring is unknown, since there are no statistical data.

At the moment, only three important pathomorphological mechanisms are known that lie at the origins of the formation of polyneuropathy:

• Wallerian degeneration;
• primary demyelination;
• primary axonopathy.

According to the immunological theory, polyneuropathy is the result of the cross-production of immune globulins that destroy their own cells, resulting in tissue necrosis and muscle inflammation.

Researchers put forward a number of hypotheses for the occurrence and problems of the course of axonal polyneuropathy:

• Vascular. It is based on the involvement of blood vessels in the process, through which oxygen and nutrients enter the peripheral nerves. The characteristics of the blood change in terms of qualitative and quantitative composition, which can lead to ischemia of nerve endings.
• Oxidative stress theory. The formation of the disease is attributed to a disturbance in the metabolism of nitric oxide, as a result of which the potassium-sodium mechanisms underlying the formation of nervous excitation and the conduction of impulses along the nerves change.
• Theory of deactivation of nerve growth factors. It suggests that the disease occurs due to a lack of axonal transport with the subsequent development of axonopathy.
• Immunological. Explains the development of the disease as a result of cross-formation of antibodies to the structures of the peripheral nervous system, which is accompanied by autoimmune inflammation and then necrosis of the nerves.

Even with the use of ultra-modern diagnostic methods, it is difficult to find a reliable cause of the pathology; it is possible to find out only in 50-70% of victims.

There are a lot of factors for the occurrence of polyneuropathy of the lower extremities of the axonal type. However, even innovative research methods do not allow us to establish the true etiology of the disease.

Expert opinion

Author: Alexey Vladimirovich Vasiliev

Head of the Research Center for Motor Neuron Disease/ALS, Candidate of Medical Sciences, doctor of the highest category

Axonal polyneuropathy is one of the most dangerous neurological diseases, accompanied by damage to the peripheral nervous system. During the disease, peripheral nerve fibers are destroyed.

There are several reasons for the occurrence of axonal polyneuropathy. The most common:

1. Diabetes mellitus disrupts the structure of the blood that nourishes the nerves, which in turn causes a disruption in metabolic processes.
2. Long-term deficiency of B vitamins. They are the most important for the proper functioning of the nervous system, so a long-term deficiency can lead to axonal polyneuropathy.
3. The effects of toxins on the body. These include a variety of poisonous substances, for example, alcohol, as well as HIV. In case of poisoning with hazardous substances, the disease can develop within a few days.
4. Hereditary factor.
5. Guillain-Barre syndrome.
6. Various injuries, which also include long-term compression of the nerves, which is typical for hernia or osteochondrosis.
Treatment of axonal polyneuropathy must be comprehensive, otherwise the desired effect will not be achieved. It is strictly forbidden to self-medicate and if the first symptoms occur, you should immediately consult a doctor. Doctors at the Yusupov Hospital select treatment individually for each patient. Depending on the severity of the pathology and symptoms, complex treatment is prescribed under the supervision of experienced specialists.

Causes and mechanisms of development of diabetic neuropathy

The main cause of diabetic neuropathy is chronically elevated blood glucose levels.

, ultimately leading to changes in the structure and functioning of nerve cells.
Due to impaired carbohydrate metabolism in diabetes mellitus, patients develop microangiopathies
- pathological changes in the vessels of the microvasculature, due to which the normal blood supply to the nerves is disrupted. As a result of multiple metabolic disorders, swelling of the nervous tissue develops, all metabolic processes in the nerve fibers are disrupted, the conduction of nerve impulses deteriorates, the antioxidant system is inhibited, leading to the accumulation of free radicals that have a detrimental effect on nerve cells, the production of autoimmune complexes begins, which ultimately can lead to atrophy of nerve fibers.

There are a number of factors that increase the risk of developing diabetic neuropathy:

- old age;

- long history of diabetes mellitus;

— decompression phase;

- increased blood pressure;

- overweight and obesity;

- smoking, drinking alcoholic beverages.

Causes

The most common causes of axonal polyneuropathy of the lower extremities:

• exhaustion of the body;
• long-term deficiency of B vitamins;
• ailments leading to dystrophy;
• acute infections;
• toxic damage from mercury, lead, cadmium, carbon monoxide, alcoholic beverages, methyl alcohol, organophosphorus compounds, medications taken without the consent of a doctor;
• diseases of the cardiovascular, hematopoietic, circulatory and lymphatic systems;
• endocrinological pathologies, including insulin dependence.

The main factors that provoke the development of motor or sensorimotor axonal polyneuropathy are:

• endogenous intoxication in renal failure;
• autoimmune processes occurring in the body;
• amyloidosis;
• inhalation of toxic substances or vapors.

The disease can also be caused by heredity.

A lack of B vitamins in the body, and especially pyridoxine and cyanocobalamin, has an extremely negative effect on the conductivity of nerve and motor fibers and can cause sensory axonal polyneuropathy of the lower extremities. The same happens with chronic alcohol intoxication, helminthic infestation, and diseases of the gastrointestinal tract, which impair the rate of absorption.

Toxic poisoning with drugs, aminoglycosides, gold salts and bismuth occupy a large percentage in the structure of factors of axonal neuropathy.

In patients with diabetes, peripheral nerve function is impaired due to the neurotoxicity of ketone bodies, i.e. metabolites of fatty acids. This happens due to the body’s inability to use glucose as the main source of energy. Therefore, fats are oxidized instead.

With autoimmune diseases occurring in the body, the human immune system attacks its own nerve fibers, perceiving them as a source of danger. This occurs due to a provocation of the immune system that occurs when taking immunostimulating medications and unconventional treatment methods carelessly. Therefore, in people who are prone to autoimmune diseases, the triggering factors for axonal polyneuropathy are:

• immunostimulants;
• vaccines;
• autohemotherapy.

With amyloidosis, a protein called amyloid accumulates in the body. It is this that disrupts the basic functions of nerve fibers.

First signs

The disease usually begins to develop with damage to thick or thin nerve fibers. Often, axonal polyneuropathy has a distal symmetrical distribution on the hands or feet. Neuropathy most often affects the lower extremities first and then spreads symmetrically up the body. The most common primary symptoms of damage include:

• muscle weakness;
• pain syndrome in the limbs;
• burning;
• crawling sensation;
• numbness of the skin.

Symptoms are most pronounced in the evening and at night.

Peripheral neuropathy

Peripheral diabetic neuropathy occurs predominantly in the lower extremities and is characterized by burning and painful sensations in the legs, often occurring at night, a feeling of sudden heat or cold, and pins and needles in the legs. Patients are very sensitive to touch, sometimes it is even painful. Deformations of the muscles of the limbs may be observed. Any damage. violating the integrity of the skin of the extremities become wounds that do not heal over a long period.

Symptoms

Doctors divide the chronic, acute and subacute course of axonal polyneuropathy. The disease is divided into two types: primary axonal and demyelinating. During the course of the disease, demyelination is added to it, and then a secondary axonal component.

The main manifestations of the disease include:

• weakness in the muscles of the legs or arms;
• spastic paralysis of the limbs;
• feeling of twitching in muscle fibers;
• dizziness with a sudden change in body position;
• swelling of the limbs;
• burning;
• tingling;
• crawling sensation;
• decreased sensitivity of the skin to high or low temperature, pain and touch;
• impaired speech clarity;
• problems with coordination.

The following symptoms are considered vegetative signs of sensorimotor polyneuropathy of the asconal type:

• rapid or, on the contrary, slow heart rate;
• excessive sweating;
• excessive dry skin;
• change in skin color;
• ejaculation disorder;
• erectile disfunction;
• problems with urination;
• failure of motor functions of the gastrointestinal tract;
• increased salivation or, conversely, dry mouth;

• eye accommodation disorder.

The disease manifests itself in dysfunction of damaged nerves. It is the peripheral nerve fibers that are responsible for the motor functions of muscle tissue, sensitivity, and also have a vegetative effect, that is, they regulate vascular tone.

Disorders of nerve conduction function are characterized by sensitivity disorders, for example:

• crawling sensation;
• hyperesthesia, that is, increased sensitivity of the skin to external irritants;
• hypoesthesia, that is, decreased sensitivity;
• lack of sensation of one's own limbs.

When autonomic fibers are affected, the regulation of vascular tone goes out of control. With axonal demyelinating polyneuropathy, compression of the capillaries occurs, causing the tissue to swell. The lower and then the upper limbs, due to the accumulation of fluid in them, significantly increase in size. Since with polyneuropathy of the lower extremities the main amount of blood accumulates in the affected areas of the body, the patient experiences persistent dizziness when taking an upright position. Due to the loss of trophic function, erosive and ulcerative lesions of the lower extremities may occur.

Axonal motor polyneuropathy manifests itself in motor disorders of the upper and lower extremities. When the motor fibers responsible for the movements of the arms and legs are damaged, complete or partial muscle paralysis occurs. Immobilization can manifest itself in a completely atypical manner - you can feel both stiffness of the muscle fibers and their excessive relaxation. With a moderate degree of damage, muscle tone is weakened.

During the course of the disease, tendon and periosteal reflexes may be strengthened or weakened. In rare cases, a neurologist does not observe them. The disease can often affect the cranial nerves, which are manifested by the following disorders:

• deafness;
• numbness of the sublingual muscles and tongue muscles;
• inability to swallow food or liquid due to problems with the swallowing reflex.

When the trigeminal, facial or oculomotor nerve is affected, the sensitivity of the skin changes, paralysis develops, facial asymmetry and muscle twitching occur. Sometimes, when axonal demyelinating polyneuropathy is diagnosed, the lesions of the upper or lower extremities may be asymmetrical. This happens with multiple mononeuropathy, when the knee, Achilles and carporadial reflexes are asymmetrical.

Diagnostics

The main research technique, which makes it possible to detect the localization of the pathological process and the degree of nerve damage, is electroneuromyography.

To determine the cause of the disease, doctors prescribe the following tests:

• determination of blood sugar levels;
• toxicology tests;
• complete urine and blood analysis;
• detection of cholesterol levels in the body.

Violation of nervous functions is established by determining temperature, vibration and tactile sensitivity.

During the initial examination, a visual research technique is used. That is, the doctor to whom the victim turned with complaints examines and analyzes such external symptoms as:

• blood pressure level in the upper and lower extremities;
• sensitivity of the skin to touch and temperature;
• presence of all necessary reflexes;
• diagnosis of swelling;
• study of the external condition of the skin.

Axonal polyneuropathy can be identified using the following instrumental studies:

• magnetic resonance imaging;
• nerve fiber biopsy;
• electroneuromyography.

Treatment of axonal polyneuropathy

Treatment of axonal polyneuropathy should be comprehensive and aimed at the cause of the disease, its mechanisms and symptoms. The guarantee of effective therapy is timely detection of the disease and treatment, which is accompanied by an absolute abstinence from cigarettes, alcohol and drugs, maintaining a healthy lifestyle and following all doctor’s recommendations. First of all, the following therapeutic measures are carried out:

• getting rid of toxic effects on the body, if present;
• antioxidant therapy;
• taking medications that affect the tone of blood vessels;
• replenishment of vitamin deficiency;
• regular monitoring of plasma glucose concentrations.

Special attention is paid to treatment aimed at relieving acute pain syndrome.

If peripheral paresis is present, that is, a significant decrease in muscle strength with a multiple decrease in the amplitude of movements, then physical therapy and special physical exercises aimed at restoring tone to muscle tissue and preventing the formation of various contractures are mandatory. Regular psychological support is especially important, which prevents the patient from falling into depression, accompanied by sleep disorders and excessive nervous excitability.

Treatment of axonal polyneuropathy is a long process, since nerve fibers take a long time to recover. Therefore, you should not expect an immediate recovery and return to your usual lifestyle. Drug therapy includes drugs such as:

• pain reliever;
• glucocorticoids;
• B vitamins;
• antioxidants;
• vasodilators;
• agents that accelerate metabolism and improve blood microcirculation.

Drug therapy is aimed at restoring nerve function, improving the conductivity of nerve fibers and the speed of signal transmission to the central nervous system.

Treatment should be carried out in long courses that should not be interrupted, although the effect does not appear immediately. To eliminate pain and sleep disturbances, the following medications are prescribed:

• antidepressants;
• anticonvulsants;
• drugs that relieve arrhythmia;
• painkillers.

Non-steroidal anti-inflammatory drugs are used to relieve pain. But it is worth remembering that they can only be used for a short period of time, since long-term use can lead to damage to the mucous membrane of the gastrointestinal tract.

Physiotherapeutic methods for treating axonal polyneuropathy include:

• magnetic wave therapy;
• mud therapy;
• electrical stimulation;
• acupuncture;
• massotherapy;
• physical training;
• ultraphonophoresis;

• galvanotherapy.

It is physical therapy that allows you to maintain the performance of muscle tissue and maintain the limbs in the desired position. Regular exercise will restore muscle tone, flexibility and increase the range of motion to normal.

Treatment of multifocal motor neuropathy

Patients with clinical manifestations of MMN are prescribed therapy with intravenous immunoglobulin (a proven and effective method). In some cases (in the absence of a therapeutic response to IVIG), immunosuppressive therapy with cyclophosphamide may be prescribed. However, for now, such treatment is considered experimental, not only due to the partial effectiveness and lack of research on this method, but also due to the toxicity of the cytostatic drug. Improvement usually occurs 3-6 weeks after starting IVIG therapy. Then the achieved effect decreases, so patients need maintenance therapy - immunoglobulin injections every 2-6 weeks.

If multifocal motor neuropathy is treated in a timely manner (at an early stage of the disease), most patients manage to avoid disability.

Features and benefits of treatment for multifocal motor neuropathy at the Rassvet Clinic

Treatment of multifocal motor neuropathy requires a multidisciplinary approach - coordinated work of therapists, neurologists, immunologists and orthopedists, as well as specific knowledge of these specialists about methods of diagnosing and treating rare diseases of the nervous and muscular systems.

Dawn doctors specialize in complex diagnoses and rare diseases, and are constantly interested in the results of research reflecting new approaches and advances in the diagnosis and treatment of orphan pathologies. If you or your loved ones experience clinical manifestations of a rare neuromuscular disease, we recommend that you contact our neurologists. Timely treatment of this group of diseases allows one to achieve an effective result and maintain the patient’s quality of life.

Prevention

The patient must take preventive measures that will help avoid relapse or the occurrence of a dangerous disease. They include enriching the diet with vitamins, regular monitoring of blood sugar levels, and complete cessation of smoking, drugs and alcoholic beverages.

To prevent the disease, it is recommended:

• wear comfortable shoes that do not pinch the foot, impairing blood flow;
• regularly inspect your shoes to avoid the formation of fungus;
• avoid walking long distances;
• do not stand in one place for a long time;
• wash your feet with cool water or do contrast baths, which helps improve blood circulation in the body.

Victims in remission are strictly prohibited from taking medications without the consent of the attending physician. It is important to promptly treat inflammatory diseases, take precautions when working with toxic substances that have a detrimental effect on the body, and regularly perform therapeutic physical exercises.