Peripheral neuropathy is a condition in which nerves of the peripheral nervous system are damaged. This peripheral nervous system is a network of nerves that transmits information from the body to and from the central nervous system (brain and spinal cord).
The symptoms of peripheral neuropathy depend on the nerve that has been damaged. If sensory nerves which send information to the brain about sensations like pain and touch are destroyed, the symptoms include pain, numbness, tingling, pricking and burning sensations.
If motor nerves which control the conscious movement of muscles are affected, the symptoms of the neuropathy include muscle weakness, painful cramps and fasciculations which are uncontrollable muscle twitches. The muscle may also become paralyzed and cause inability to grasp things or walk.
If autonomic nerves which regulate automatic activities like digesting food are damaged the symptoms include inability to digest food properly, diarrhea, constipation and stool incontinence. Other symptoms of autonomic neuropathy include inability to sweat normally which can lead to heat intolerance, irregular beating of the heart and failure to maintain normal blood pressure levels which can cause dizziness and fainting spells.
The causes of peripheral neuropathy are either inherited or acquired. Inherited forms are caused by inborn errors in the genetic code or changes in the genes which are known as genetic mutations. Examples of inherited polyneuropathies include Charcot Marie Tooth disease which is characterized by numbness, weakness and wasting of the leg muscles with resultant gait (walking) abnormalities.
Acquired peripheral neuropathies can be caused by physical trauma which can stretch, crush or cut the nerves. This trauma is usually from automobile accidents and sports related activities.
Toxins like arsenic, lead, thallium and mercury can also damage the nerves. Some medications like those used to treat cancer and seizures can also cause peripheral neuropathy. Alcoholism and nutritional deficiencies like thiamine and B12 deficiency are other causes of this condition.
Systemic diseases which affect the entire body can also cause peripheral neuropathy. Examples include diabetes mellitus, kidney failure, liver disease and hormonal imbalances like hypothyroidism which is caused by underproduction of hormones by the thyroid gland.
Microorganisms can also attack the nerves and cause peripheral neuropathy. Examples include the human immunodeficiency virus (HIV) and the herpes zoster virus which causes shingles. Bacteria like those which cause leprosy and Lyme diseases can also affect the nerves.
Peripheral neuropathy is diagnosed on the basis of symptoms in addition to exam findings. If both are consistent with neuropathy, a nerve conduction study must be performed by a board certified neurologist and his/her neurodiagnostic technician to confirm the diagnosis. Many other conditions can mimic neuropathy, and often, more than one diagnosis is responsible for the symptoms if severe.
The treatment of peripheral neuropathy depends on the cause. Those which are inherited do not have a cure while the management of acquired neuropathies begins with treating their underlying cause. Therefore if the patient has a systemic disease like diabetes, it must be well controlled. Nutritional deficiencies must also be corrected and exposure to nerve toxins avoided. FDA approved medical vitamins are now approved for the treatment of neuropathy.
After the underlying cause has been managed symptomatic treatment is given for the symptoms being experienced by the patient. Pain medications specifically for neuropathy are therefore prescribed for those in pain and muscle relaxants for those experiencing muscle spasms. This, however, is a double edged sword. Once the pain is covered up, it is difficult to determine the progression of neuropathy until it is too late. Yearly, or twice yearly nerve conduction studies are very important to document the benefit of treatment, or change treatment course if worsening of the neuropathy is noted.
Supportive measures used to treat peripheral neuropathies include following a physician-supervised exercise program which includes both active and passive forms of exercise to improve muscle strength and prevent wasting.
The surgical treatment of peripheral neuropathy is reserved for those with symptoms caused by compression of the nerves by tumors, swollen blood vessels or slipped disks.
The treatment of peripheral neuropathy is important since if left untreated the condition progresses as the nerve damage continues. Some patients however may experience periods of relief which are followed by relapses. The result of not treating the neuropathy is that the patient’s physical and emotional well-being as well as their quality of life deteriorates.
The current research on peripheral neuropathy by St. George’s University of London reveals that loss of sensation in the feet can be a predictor of cardiovascular events like heart attacks and strokes in patients with diabetes.
The support groups for patients with neuropathy in Tennessee meets at Tellico Village Community Church on the 1st Wednesday of each month at 6 p.m. Their website is http://www.neuropathy.org/site/PageServer?pagename=sup_us_tennessee and address is Christian Life Center, 130 Chota Center, Loudon TN 37774. The contact person is James Fella who can be contacted by phone at 865 458 1781 or via email at email@example.com