Several pathologies can be the cause of neuropathic pain. Certain neurological diseases modify certain functions of the nervous system and disrupt the electrical circuit of the nerves causing the sensation of pain. Dysesthesia: all you need to know about variations in sensitivity.

A sensory disorder is an abnormal sensation, relatively painful and unpleasant, which is caused by the attack of the sensory pathways which travel by the nerves, then the spinal cord and which go to the brain.  

Dysesthesia is one of the sensory disorders which results in an abnormally unpleasant sensation, characterized by a decrease or an exaggeration of the sensitivity. It can be expressed by sensations of numbness, tingling or burning and be related to a lesion of the spinal cord. It can be spontaneous or provoked.

The term “dysesthesia” is formed from the Greek roots dys (anomaly) and aesthesia (sensation).

Dysesthesia is an abnormal sensation caused by nervous dysfunction. Contacts in the affected area cause a more or less painful, abnormal sensation, sometimes downright painful. 

The origin of the disorder can be a pathology affecting nerve endings or the path of a sensory nerve.

The causes of traumatic origins

• Nerve trauma by tearing, stretching;
• Surgery (surgery can cause nerve damage leading to dysesthesia, especially dental surgery);
• Scar neuroma;
• Amputation with constitution of a phantom limb syndrome;
• Compression: herniated disc, tumor.

Tumor invasion

• Cancer: frequent coexistence of nociceptive pain and neuropathic pain.

Causes of toxic origins

• Chemotherapy;
• Anti-tuberculosis drugs.

Causes of infectious origins

• Shingles can cause chronic dysesthesia, usually very localized;
• Lyme disease ;
• VIH;
• Other infectious neuropathies of viral origin.

Metabolic causes

• Neuropathies carentielles ;
• Diabetes (common cause of dysesthesia linked to chronic excess sugar in the blood). 

Fixed or progressive brain damage

• Cerebro-injured (after anoxia, drowning, etc.), degenerative diseases (lysosomal, leukodystrophies, etc.).

Alcoholic withdrawal

• Alcohol withdrawal can lead to the onset of transient dysesthesia.

Autoimmune diseases

• Guillain Barré syndrome: causing damage to the sheaths surrounding and protecting the nerve fibers;
• Multiple sclerosis: this is likely to cause an alteration in the communication of sensitive information. Sensory or motor messages can then be disturbed.

Dysesthesias can affect the whole body. An unpleasant sensation or even pain can be caused simply by contact with a garment.

• Dysesthesia is local: case of the jaw where there may be an abnormal sensation at the level of a removed tooth;
• Dysesthesias are redoubled by sudden changes in temperature and heat; 
• Mood (anxiety, depression) or personality disorders often associated with dysesthesia.

Treatment of neuropathic pain is often difficult. Complete disappearance of pain is rare. The goal is to radically reduce symptoms to resume activity and improve quality of life.

Drug treatments

• Analgesics : classic analgesics are not very effective in neuropathic pain. Thus, analgesics such as paracetamol, non-steroidal anti-inflammatory drugs, salicylates (level 1) will be prescribed. In the event of failure, other stronger analgesics may also be prescribed such as tramadol, whether or not associated with paracetamol, codeine combined with paracetamol, opium powder combined with paracetamol, or possibly dihydrocodeine (level 2). As a last resort, there is morphine (level 3);
• Antidepressants and antiepileptics : antidepressants and antiepileptics are the drugs most used in a neuropathic context. The application of patches containing a local anesthetic to the painful areas may also be part of the treatment. However, be careful with contraindications and undesirable effects.

It is often difficult to assess the effectiveness of treatment for neuropathic pain. The minimum effective dosage should always be sought. In order to assess the efficacy and tolerance to the treatment, a frequent reassessment will be carried out. Improvements can then be made.

Non-drug treatments

In addition to drug treatment, other therapeutic solutions can help reduce neuropathic pain. Their effectiveness has never been scientifically proven but its ways could even increase the effectiveness of the initial treatment. These are for example:

• Massages;
• Physiotherapy;
• Applying heat to painful areas;
• Relaxation;
• Physiotherapy;
• Acupuncture;
• Psychotherapy

Whether chronic or acute, neuropathic pain can be controlled. Always take care of the primary disease, associated with a healthy, balanced and adapted diet to reduce pain and prevent the risk of complications.