Nerve Pain: Polyneuropathy

Overview

Polyneuropathy is the most common form of peripheral neuropathy, a condition involving damage to the peripheral nerves — which are outside the brain and spinal cord — and the symptoms that result from that damage. In this form of neuropathy, multiple nerves are affected, and frequently, nerves throughout the body will be affected simultaneously.

Polyneuropathy affects several nerves in different parts of the body at the same time. In cases of a mononeuropathy, just one nerve is affected.

Polyneuropathy can affect nerves responsible for feeling, movement (motor neuropathy), or both (sensorimotor neuropathy).

It may also affect the autonomic nerves responsible for controlling functions such as digestion, the bladder, blood pressure, and heart rate.

Although the exact number of people with polyneuropathy is not known, the National Institute of Neurological Disorders and Stroke (NINDS) estimate that approximately 20 million people in the United States have some form of peripheral neuropathy, and most of them have polyneuropathy.

Symptoms

Polyneuropathy can produce a variety of symptoms, depending on which nerves are affected.

Symptoms associated with sensory or motor nerve damage can include:

• tingling
• numbness
• pins and needles
• difficulty using the arms, legs, hands, or feet
• increased pain (such as burning, stabbing, freezing, or shooting pains)
• sleep problems due to night-time pain
• inability to feel pain
• extreme sensitivity to touch
• inability to sense temperature changes
• lack of coordination
• increased episodes of falling
• changes to the skin, hair, or nails
• foot and leg ulcers
• skin and nail infections
• muscle weakness
• muscle twitching

Symptoms associated with autonomic nerve damage include:

• heat intolerance

• unusual sweating

• bladder problems

• digestive problems

• dizziness

• blood pressure or pulse abnormalities

• difficulty eating or swallowing

• difficulty breathing

• inability to sense temperature changes

• lack of coordination

Causes and risk factors

A variety of medical conditions and other factors can cause polyneuropathy, including:

• Diabetes: This can be a significant risk factor, especially if blood glucose levels are poorly controlled. One study of more than 1,400 people with type 2 diabetes found that every fifth person had diabetic neuropathy.
• Alcohol abuse: Alcohol can damage nerve tissue, and alcohol abuse is often associated with nutritional deficiencies that contribute to neuropathy.
• Autoimmune conditions: The immune system attacks the body, causing damage to nerves and other areas. Conditions include Sjogren’s syndrome, celiac disease, Guillain-Barré syndrome, and  lupus.
• Bone marrow disorders: Examples of these include abnormal proteins in the blood, some forms of bone cancer, and lymphoma.
• Exposure to toxins: Toxic neuropathy may be caused by exposure to industrial chemicals such as arsenic, lead, mercury, and thallium. Drug or chemical abuse is also a risk factor.
• Hypothyroidism: An underactive thyroid may lead to polyneuropathy, although this is uncommon.
• Kidney disease: Uremic neuropathy is a form of polyneuropathy that affects 20 to 50 percents of people with kidney disease, according to the Center for Peripheral Neuropathy.
• Liver disease: Research indicates that peripheral neuropathy is very common in those with cirrhosis of the liver.
• Medications: Chemotherapy, along with some drugs used to treat HIV/AIDS, can cause neuropathy.
• Poor nutrition: Deficiencies of vitamins B-1, B-6, B-12, and E may lead to polyneuropathy, as these are vital for nerve health.
• Physical trauma or injury: Repetitive motion such as typing, accidents, or other injuries can damage peripheral nerves.