Neuropathy is a disease of dysfunction of one or more peripheral nerves, typically causing numbness or weakness. The term “neuropathy” covers a wide area and many nerves, but symptoms depend on the type of nerves that are affected:
Sensory nerves control sensation; neuropathy often causes tingling, pain, numbness or weakness in the feet and hands.
Motor nerves allow power and movement; neuropathy causes weakness in the feet and hands.
Autonomic nerves regulate internal organ functions such as the heart, stomach and intestines; neuropathy causes changes in the heart rate and blood pressure or excessive sweating.
A number of conditions may lead to neuropathy, and any nerve types can be affected at any one time. Causes of neuropathy include but are not limited to, diabetes, B12 or folate vitamin deficiencies, shingles, drugs used for chemotherapy or HIV treatment, cancers, chronic kidney disease and alcohol excess. Approximately 30% of neuropathy are idiopathic or of unknown cause.
Diabetes is the most common cause of neuropathy. High blood sugar levels causes damage to blood vessel walls that supply oxygen and nutrients to the nerves and causes subsequent nerve damage.
There are 4 common types of diabetic neuropathy
Peripheral neuropathy affects feet, legs, hands and arms. Nerve-ending damage leads to burning, tingling, loss of pain or temperature sensation, sensitivity to touch, and/or difficult, painful walking.
Autonomic neuropathy affects key organ systems, resulting in a wide range of symptoms in the respiratory, visual, circulatory, reproductive and digestive systems. For example, a patient may experience the excessive need for food, increased heart rate, sexual difficulties and inability to regulate body temperature.
Proximal neuropathy targets nerves located in or near hips, thighs, buttocks or shoulders causing pain, leg muscle weakness and weight loss.
Focal neuropathy affects just one or a small group of nerves anywhere in the body. It can produce pain, weakness or both.