What is Polyneuropathy?

Polyneuropathy, the most common form of a group of disorders known as peripheral neuropathy, is caused by damage to peripheral nerves (defined as all nerves beyond the brain and spinal cord). Peripheral nerves travel from the spinal cord to muscles, skin, internal organs, and glands. In polyneuropathy, many nerves throughout the body malfunction at the same time.

Although there are different causes of polyneuropathy, the symptoms remain relatively constant and can include:

  • Pain
  • Numbness
  • Tingling or burning
  • Hypersensitivity
  • Weakness in the arms or legs.

Some neuropathies may involve muscles used in swallowing, breathing or eye movement.

The neuromuscular team at Virginia Mason offers a multidisciplinary approach to the treatment of peripheral nerve disorders. Expert neurologists, neurosurgeons, physical medicine specialists, speech therapists, physical and occupational therapists, neuropsychologists, respiratory therapists, nutritionists and others are available to every patient to ensure the best possible outcome. For more information about polyneuropathy, or to schedule an appointment at Virginia Mason's Neuroscience Institute, call (206) 341-0420.

What Causes Polyneuropathy?

Neuropathies of all types generally fall into three categories: acquired, hereditary and idiopathic (no known cause).

One of the most common forms of an acquired neuropathy is diabetic neuropathy, which is the result of poorly controlled blood sugar levels in people with diabetes. Though less common, diabetes can also cause mononeuropathy, often characterized by weakness of the eye or of the thigh muscles.
Other causes of acquired neuropathies include exposure to certain toxins, poor nutrition (particularly vitamin B deficiency), infections, traumatic injuries, autoimmune disorders and complications from diseases such as cancer or kidney failure.

Hereditary neuropathies are not as common. In cases of hereditary disease a specific gene may be passed on from parent to child. The most common of these is Charcot-Marie-Tooth disease, which can take different forms and is characterized by a slowly progressive degeneration of the muscles in the foot, lower leg, hand and forearm, and a mild loss of sensation in the limbs, fingers and toes.

Idiopathic, which means "of unknown cause," is the classification for up to one-third of diagnosed neuropathies. Typically, idiopathic neuropathies occur in people over 60 years old and progress slowly, or remain unchanged after initial onset.

Guillain-Barré Syndrome

A serious but rare form of acquired polyneuropathy is Guillain-Barré syndrome (GBS), a disease that strikes suddenly when the body's immune system attacks peripheral nerves. Early symptoms include weakness, tingling, and loss of sensation in the legs that eventually spreads to the arms. In critical cases problems with blood pressure, breathing and heart rhythm may occur. However, despite the severity of the disease, recovery rates are good when patients receive treatment early.

Virginia Mason's Neuroscience Institute has extensive experience in treating GBS. Patients with the disorder benefit from the close collaboration of the neurology care team working together with physical medicine and rehabilitation. This coordinated treatment plan offers patients one location to receive the most advanced medical care available for their individual condition.

Treatment for Polyneuropathy

The goal of treatment is to control symptoms, which sometimes involves treating the underlying cause, if known (such as diabetes). When the underlying cause is corrected, neuropathies often improve on their own. What treatment is given also depends on how severe the symptoms are. Simply controlling pain can be an important part of neuropathy treatment. The most aggressive therapy is usually reserved for symptoms that greatly interfere with daily functioning.

Therapies for controlling pain caused by polyneuropathy may include:

  • Pain medications - Over-the-counter pain medications may be adequate for mild symptoms. For more severe pain, prescription painkillers may be used. Some painkillers can lead to dependence and other side effects, so they are generally prescribed when other treatments fail.
     
  • Corticosteroids - Corticosteroids are anti-inflammatory drugs that can relieve the severe pain associated with nerve irritation and inflammation. They may be taken orally, or injected directly into the areas of the body where there is pain. Corticosteroids can greatly reduce and may eliminate pain for extended periods of time.
     
  • Anti-seizure medications - Drugs that were originally developed to treat epilepsy are sometimes used to relieve nerve pain. The side effects of these drugs can cause drowsiness and dizziness.
     
  • Transcutaneous electrical nerve stimulation (TENS) - TENS is a drug-free therapy that works by applying very small electrical impulses on specific nerve paths. The electrical impulses are delivered through electrodes placed on the skin. Although it doesn't work for everyone or all types of pain, TENS may be prescribed in combination with other treatments, primarily to provide relief from acute forms of nerve pain.
     
  • Antidepressants - Certain antidepressants have been found to help relieve pain caused by neuropathy by interfering with chemical processes in the brain involved in the pain response.

When more aggressive treatment is needed for progressive types of neuropathy causing serious physical dysfunction, some options include:

  • Immunosuppressant medications, including those that contain antibodies that curb the autoimmune processes leading to nerve damage.
     
  • Removing malfunctioning antibodies from the blood by way of plasmapheresis, a process that clears antibodies from the plasma portion of blood before being put back in the body.

Wellness and Alternative Therapies

Certain lifestyle choices and wellness techniques may help people with polyneuropathy manage their disorder.

  • Stay active - Exercise is shown to help reduce neuropathy pain.
     
  • Practice good foot care - Avoid tight socks and shoes that can worsen pain. Check feet often for developing problems, such as blisters or excessive calluses. Foot massages can also be helpful by stimulating circulation.
     
  • Be aware of pressure points - Avoid prolonged pressure on nerves by not crossing the legs or leaning on arms or elbows for long periods.
     
  • Don't smoke - Smoking decreases circulation and can worsen the effects of neuropathy.

Alternative therapies have helped ease symptoms of neuropathy in some patients. Astrid Pujari, MD, is a physician trained in Integrative medicine (holistic medicine) and Western medicine. She offers monthly group sessions at Virginia Mason to discuss nutrition, supplements, cancer, mind-body practice and holistic medicine. In addition, Dr. Pujari and other practitioners offer seminars on using illness as a means of transformation.

Although alternative therapies have not been studied as extensively as drug treatments for neuropathies, most are relatively safe to use. They include:

  • Acupuncture - Acupuncture should be performed by a certified practitioner. It may take several sessions before symptoms improve.
     
  • Alpha lipoic acid - Alpha lipoic acid is a naturally occurring fatty acid found in every cell in the body. It converts blood sugar into energy to fuel the body's functions. Alpha lipoic acid is also an antioxidant, which may work to protect cells from damage from free radicals. Because it can affect blood sugar levels, patients should consult with a physician before using this over-the-counter supplement.
     
  • Capsaicin - A naturally occurring substance found in hot peppers, capsaicin can moderately improve neuropathy symptoms. Available in a cream, patients must gradually develop a tolerance for the heat created on contact before enjoying relief of their pain.

For more information about polyneuropathy, contact Virginia Mason's Neuroscience Institute at (206) 341-0420.