What is Polyneuritis?
Polyneuritis is a condition that involves the lower motor and sensory neurons characterized by an inflammation that affects multiple nerves. It is an inflammatory condition resulting in lesions of the peripheral nerves. The condition of Polyneuritis affects the peripheral nervous system that makes up the complex network that connects the brain and the spinal cord to the internal organs, muscles and skin.
The peripheral nervous system contains all the nerves located outside the central nervous system. The key role of the peripheral nervous system is to connect the central nervous system to the internal organs, skin and limbs of the human body. The nerves in the peripheral nervous system are made up of axons or bundles of axons with size ranging from small nerves to large nerves. It is divided into two parts namely the somatic nervous system and the autonomic nervous system. The sensory nervous system is responsible for transmitting sensory and motor information to the central nervous system. The autonomic nervous system is responsible for controlling the involuntary body functions. Both two parts of the peripheral nervous system are vital for the normal function of the body that damages in any or all parts of the peripheral nervous system can bring a drastic effect on the normal function of the body.
The signs and symptoms of Polyneuritis depend on the nerve that is affected. The initial onset of symptoms is usually in the longest nerve that reaches the toes.
Sensory nerve is responsible for receiving different sensation such as hot and cold. When this nerve is affected or damaged it can result in symptoms of paresthesia, burning pain, numbness and loss position sense and vibration sense. The loss of sensation can subject an affected individual at risk for burn due to the alteration in sensing temperature. The numbness and tingling in the feet or hand gradually appear and may extend up to the legs and the arms. Sensitivity to touch is extreme even with the slightest touch.
Motor nerve controls the muscle movement and damage to this part of the peripheral nervous system can bring symptom such as:
- Lack of coordination
- Paralysis or muscle weakness
- Loss of bladder or bowel control
- Dry and pale skin due to diminished sweating
- Diarrhea or constipation
Autonomic nerve is responsible for controlling the involuntary body functions. Polyneuritis affecting this nerve results in symptoms such as:
- Cold extremities
- Heat intolerance
- Abnormally low blood pressure
- Dizziness or lightheadedness
- Erectile dysfunction
- Digestive problems
- Dry and scaling skin
Muscle wasting is also exhibited in Polyneuritis and is characterized by thin and weak muscles. The muscle tissue wasting leads to its detachment from the motor nerve resulting in symptoms of diminished movement and loss of muscle strength.
Polyneuritis has no single cause and the etiology is rather difficult to determine. Numerous factors can be implicated in the onset of Polyneuritis and these may include the following:
Autoimmune disease such as Guillain-Barre syndrome is among the implicated in the incidence of Polyneuritis. It is a rare disorder where the immune system attacks the peripheral nerve resulting in damage in the myelin sheaths that surrounds the nerves. Other autoimmune disease includes lupus, rheumatoid arthritis, necrotizing vasculitis, Sjogren's syndrome and chronic inflammatory demyelinating polyneuropathy.
Metabolic and endocrine disorders such as diabetes, uremia, acromegaly, gout, and amyloidosis and thyroid dysfunction are also implicated in the onset of Polyneuritis.
Chemical exposures are also considered in the cause of Polyneuritis and such exposures include toxic substances, carbon monoxide, carbon disulfide, carbon tetrachloride, arsenic, lead, mercury and thallium.
Infectious diseases include direct infection of the peripheral nerve such as leprosy and herpes zoster. Associated or secondary acute or chronic infection such as measles, chicken pox, scarlet fever, mumps and influenza are also considered in the etiology of Polyneuritis. Bacterial toxins secreted by the peripheral nerves such as tetanus are also included in the cause of Polyneuritis.
Nutrition disorder such as Vitamin B12 deficiency is also among the cause of Polyneuritis. Beriberi, pellagra, chronic alcoholism and chronic gastrointestinal diseases are among the nutrition disorder implicated in Polyneuritis.
Medications can also cause Polyneuritis often as a side effect of certain drugs. Medications intended for the treatment of cancer is among the medications that can cause Polyneuritis aside from other drugs such as sulfonamides, phenytoin, isoniazid, cytarabine, Ethambutol and others.
Trauma directed to the nerve such as from sports injuries, falls and vehicular accidents can result to nerve damage that may lead to Polyneuritis.
The initial treatment of Polyneuritis involves a neurologic evaluation to determine the nerves involved in the onset of the disorder. The method of treatment depends on the underlying condition resulting to Polyneuritis.
Medications of various types can be used to relieve the symptom of pain in the disorder and other medications may include the following:
- Anti-seizure drugs
- Pain relievers
- Immunosuppressive drugs
- Antidepressant drugs
Transcutaneous electrical nerve stimulation is also utilized to relieve the symptoms by applying gentle electric current.
A support device such as walking aids and foot or hand braces may be required for patients with severe weakness of the legs or the arms to help the patient to move. A splint may also be given to facilitate weak wrist extension.
Polyneuritis often resolves or improves on its own when appropriate treatment of the underlying condition is applied.