Chronic Symmetrical Peripheral Neuropathy The largest group of polyneuropathies, they develop gradually over time and affect nerves throughout the body.Acute Symmetrical Peripheral Neuropathy Rare, this severe, rapidly developing form of polyneuropathy affects nerves throughout the body and is most often seen in Guillain-Barré syndrome, an autoimmune disorder that attacks the peripheral nervous system and can be fatal.Multiple Mononeuropathy Involving damage to at least two distinct nerve areas, this form of polyneuropathy can result from vasculitis (inflammation of the blood vessels), sarcoidosis, and some forms of cancer.
Diseases and Toxicity
Other causes of polyneuropathy include chemotherapy; HIV/AIDS and the drugs used to treat it; other metabolic disorders such as hypoglycemia or kidney failure; autoimmune disorders such as celiac disease, rheumatoid arthritis, lupus, sarcoidosis, Sjogren’s syndrome and Guillain-Barré syndrome; infections; toxicity; hereditary disorders such as Charcot-Marie-Tooth disease; hormonal disorders; alcoholism; and vitamin deficiencies. (8,9,10,11,12) Monoclonal gammopathies, abnormal proteins found in the blood, are also correlated with polyneuropathy, according to research. Damage to sensory nerves can affect sensations and sense of balance, while damage to motor nerves can affect movement and reflexes. When both sensory and motor nerves are involved, the condition is known as sensorimotor polyneuropathy, in which damage happens body-wide to nerve cells, fibers (axons), and coverings (myelin sheaths). (13) Depending on the cause and patient, symptoms of polyneuropathy can include: temporary or permanent numbness; tingling; pricking or burning sensations; increased sensitivity to touch; pain; muscle weakness or wasting; paralysis; or dysfunction in organs or glands; impairment to urination and sexual function. (2,14) “The character and quality of neuropathic pain tends to be pain that’s burning or electric in character.” Additionally, he says, the pain will often be associated with other symptoms, such as:
Paresthesia, a lack of normal sensation associated with pain, such as numbness or tingling.Allodynia, a painful response to a stimulus that wouldn’t normally trigger pain signals, such as a light touch or a cold wind.Hyperalgesia, a dramatic or severe pain in response to a stimulus that normally causes mild pain.
“Pain is a protective mechanism,” says Peter Highlander, DPM, of the Bellevue Hospital in Bellevue, Ohio. Without sensation, a person might not know when they have been injured, and something as small as a blister can become infected, develop into an ulcer, and in time a wound deep enough to require amputation of the affected body part. “I’ve had patients walk in who are profoundly neuropathic with bad fractures, and it doesn’t hurt them. They think, ‘I just sprained my ankle.’ So they just continue to walk on it and things just get worse and worse, and then a lot of times they require a major surgical reconstruction,” he explains. Polyneuropathy can lead to complications during surgery as well, says Dr. Highlander. That is because of Charcot neuropathic osteoarthropathy (or Charcot, for short), a condition in which inflammation and unaddressed injuries subject bones, joints, and soft tissues (especially those in the feet) to microfractures and deformity. If a patient knows he or she has neuropathy, that should be brought up before surgery, says Highlander, because the procedure must be handled differently. (18) Injury to a nerve or pressure on it due to some kind of compression (such as inflammation or edema) can affect a single nerve, resulting in pain, alteration or loss of sensation, loss of movement, or another type of malfunction. Physical trauma, carpal tunnel syndrome, and sciatica are among the common causes of mononeuropathy. Williams sees patients with mononeuropathy in his practice. “If an individual has an injury to areas near the knee, they may have a neuropathy that involves the peroneal nerve [which supplies sensation and movement to the lower leg and feet] and develop pain, or weakness, or numbness, or tingling in the distribution of that particular nerve. So the trauma really has to do with the peripheral nerve in close proximity to the trauma.” (21)
Carpal tunnel syndrome (also known as median nerve dysfunction), which affects movement and sensation in the hand and fingers.Axillary nerve dysfunction, which affects movement or sensation in the shoulder.Radial nerve dysfunction, which involves problems with movement and sensation in the arm, wrist, back of the arm and hand.Cubital tunnel syndrome, also known as ulnar nerve dysfunction, which affects sensation and strength in the arm, palm, ring fingers, and little fingers.Common peroneal and femoral nerve dysfunctions, which affect movement and sensation in the lower extremities.Cranial mononeuropathies involving compression, diabetes, vision or the face.Sciatic nerve dysfunction, also known as sciatica, can cause problems with the muscles in the backs of the knees and lower legs, and affects sensation in the thighs, legs, and feet.
Treatment options for mononeuropathy include many of the types of pain medications used to treat polyneuropathy. Also, pressure on the affected nerve can be relieved by surgery or steroid injections that reduce swelling. (20) Additional reporting by Joseph Bennington-Castro.
