What causes peripheral neuropathy?
There are many causes of peripheral neuropathy, including diabetes, hereditary disorders, inflammation, infections or autoimmune diseases, protein abnormalities, compression or physical trauma, exposure to toxic chemicals, poor nutrition, kidney failure, chronic alcoholism, and certain medications – especially those used to treat cancer and HIV/AIDS. In some cases, however, even with extensive evaluation, the cause of a person’s peripheral neuropathy remains unknown – this is called idiopathic neuropathy.
What are the symptoms of peripheral neuropathy?
The symptoms of peripheral neuropathy often include:
A sensation of wearing an invisible “glove” or “sock”
Burning sensation or freezing pain
Sharp, jabbing or electric-like pain
Extreme sensitivity to touch
Difficulty sleeping because of feet and leg pain
Loss of balance and coordination
Difficulty walking or moving the arms
Abnormalities in blood pressure or pulse
The symptoms of peripheral neuropathy may depend on which of the three types of peripheral nerves (motor, sensory and autonomic) have been damaged. Some neuropathies affect all three types of nerves, while others involve only one or two.
Motor nerves send impulses from the brain and spinal cord to all of the muscles in the body. This permits people to do activities like walking, catching a baseball, or moving the fingers to pick something up. Motor nerve damage can lead to muscle weakness, difficulty walking or moving the arms, cramps, and spasms.
Sensory nerves send messages in the other direction-from the muscles back to the spinal cord and the brain. Special sensors in the skin and deep inside the body help people identify if an object is sharp, rough, or smooth, if it’s hot or cold, or if a body part is still or in motion. Sensory nerve damage often results in tingling, numbness, pain, and extreme sensitivity to touch.
Autonomic nerves control involuntary or semi-voluntary functions, such as heart rate, blood pressure, digestion, and sweating. When the autonomic nerves are damaged, a person’s heart may beat faster or slower. He or she may get dizzy when standing up, sweat excessively, or have difficulty sweating at all. In addition, autonomic nerve damage may result in difficulty swallowing, nausea, vomiting, diarrhea or constipation, problems with urination, abnormal pupil size, and sexual dysfunction.