Neuropathy

• - Nerves that carry sensations (sensory).
• - Nerves that control muscles (motor).
• - Nerves that carry information to organs and glands (autonomic).

Causes

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 (mono neuropathy), or it may affect multiple nerves (poly neuropathy).

There are many reasons for nerves to malfunction. In many cases, no cause can be found.

Nerve Damage Can 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 (alcoholic neuropathy).
• - Hypothyroidism.
• - Multiple myeloma.
• - Uremia (from kidney failure).
• - Infections or inflammation, including :
• - Colorado tick fever.
• - Guillain-Barre syndrome.
• - Hepatitis .
• - HIV.
• - Lyme disease.
• - Polyarteritis 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.
• - Neuropathy secondary to medications, most commonly :
• - 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 .

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.

Tests That Find and Help Classify Neuropathy May Include :

• - Electromyogram (EMG) -- a recording of electrical activity in muscles).
• - Nerve conduction velocity tests (NCV) -- a recording of the speed at which signals travel along nerves.
• - Nerve biopsy -- taking a small sample of a nerve to look at under a microscope.