Peripheral Neuropathy

Peripheral neuropathy is very common. Because there are many types and causes of neuropathy and doctors don’t always agree on the definition, the exact incidence is not known. Some people are more likely to inherit neuropathy. Peripheral neuropathy affects at least 20 million people in the United States. Nearly 60% of all people with diabetes suffer from peripheral neuropathy.

Peripheral neuropathy is a problem with the nerves that carry information to and from the brain and spinal cord to the rest of the body. This can produce pain, loss of sensation, and an inability to control muscles.

•Peripheral means nerves further out from the center of the body, distant from the brain and spinal   cord (which are called the central nervous system)
•Neuro means nerves
•Pathy means abnormal

Causes, incidence, and risk factors
One set of peripheral nerves relays information from your central nervous system to muscles and other organs. A second set relays information from your skin, joints, and other organs back to your central nervous system. Peripheral neuropathy means these nerves don’t work properly. Peripheral neuropathy may involve damage to a single nerve or nerve group, or it may affect multiple nerves (polyneuropathy). There are many reasons for nerves to malfunction. In many cases, no cause can be found.

Nerve damage may be caused by:

•Diseases that run in families (hereditary disorders), such as:
•Charcot-Marie-Tooth disease
•Friedreich’s ataxia
•Diseases that affect the whole body (systemic or metabolic disorders) such as:
•Cancer
•Diabetes
•diabetic neuropathy
•Dietary deficiencies (especially vitamin B12)
•Excessive alcohol use>
•Multiple myeloma
•Uremia (from kidney failure)
•Infections or inflammation, including:
•Guillain-Barre syndrome
•Hepatitis
•HIV
•Lyme disease
•Polyarthritis nodosa
•Rheumatoid arthritis
•Sarcoidosis
•Sjogren syndrome
•Syphilis
•Systemic lupus erythematosus
•Exposure to poisonous substances such as:
•Glue sniffing or inhaling other toxic compounds
•Heavy metals (lead, arsenic, and mercury are most common)
•Industrial chemicals — especially solvents
•Nitrous oxide
•Cisplatin
•Isoniazid
•Paclitaxel (Taxol)
•Pyridoxine (vitamin B6)
•Vincristine
 

Miscellaneous causes:
•Compression of a nerve by nearby body structures or by casts, splints, braces, crutches, or other devices
•Decreased oxygen and blood flow (ischemia)
•Prolonged exposure to cold temperatures
•Prolonged pressure on a nerve (such as a long surgery)
•Trauma to a nerve

Symptoms
The symptoms depend on which type of nerve is affected. The three main types of nerves are:
•Nerves that carry sensations (sensory)
•Nerves that control muscles (motor)
•Nerves that carry information to organs and glands (autonomic)
Neuropathy can affect any one or a combination of all three types of nerves. Symptoms also depend on whether the condition affects one nerve, several nerves, or the whole body. When the whole body is affected, it is called polyneuropathy. Longer nerves are more easily injured than shorter ones, so it is common to have earlier or worse symptoms in the legs and feet than in the hands and arms.

SENSATION CHANGES

•Burning sensations
•Changes in sensation
•Inability to determine joint position, which causes lack of coordination
•Nerve pain
•Tingling or numbness

With many neuropathies, sensation changes begin in the toes and move toward the center of the body. Other areas become involved as the condition gets worse. Diabetes is a common cause of sensory neuropathy.

Call your health care provider if you have symptoms of peripheral neuropathy. In all cases, early diagnosis and treatment increases the chance of controlling symptoms.

Nerve pain, such as that caused by peripheral neuropathy, can be difficult to control. If your pain is severe, a pain specialist may be able to suggest helpful approaches.

Emergency symptoms include:

•Difficulty breathing
•Difficulty swallowing
•Fainting
•Irregular or rapid heartbeat