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Polyneuropathy or symmetrical polyneuropathy (poly- + neuro- + -pathy) is damage or disease affecting peripheral nerves (peripheral neuropathy) in roughly the same areas on both sides of the body, featuring weakness, numbness, pins-and-needles, and burning pain. It usually begins in the hands and feet and may progress to the arms and legs; and sometimes to other parts of the body where it may affect the autonomic nervous system. It may be acute (appearing suddenly, progressing rapidly and resolving slowly) or chronic (emerging and developing gradually). A number of different disorders may cause polyneuropathy, including diabetes and some types of Guillain-Barré syndrome.〔(【引用サイトリンク】 title= Peripheral neuropathy fact sheet )〕 Sensory polyneuropathy is the condition of having multiple sensory neuropathies, while motor polyneuropathy refers to multiple motor neuropathies. Sensorimotor polyneuropathy or sensory-motor polyneuropathy is the combination of both conditions. ==Classification== Polyneuropathies may be classified in different ways, such as by cause, by speed of progression, or by the parts of the body involved. Classes of polyneuropathy also are distinguished by which part of the nerve cell is affected mainly: the axon, the myelin sheath, or the cell body. * Distal axonopathy, or "dying-back neuropathy", is the result of some metabolic or toxic derangement of neurons. It is the most common response of neurons to metabolic or toxic disturbances, and may be caused by metabolic diseases such as diabetes, renal failure, connective tissue disease, deficiency syndromes such as malnutrition and alcoholism, or the effects of toxins or drugs such as chemotherapy (chemotherapy-induced peripheral neuropathy). They may be divided according to the type of axon affected: large-fiber, small-fiber, or both. The most distal portions of axons are usually the first to degenerate, and axonal atrophy advances slowly toward the nerve's cell body. If the cause is removed, regeneration is possible, although the prognosis depends on the duration and severity of the stimulus. People with distal axonopathies usually present with sensorimotor disturbances that have a symmetrical "stocking and glove" distribution. Deep tendon reflexes and autonomic nervous system functions also are lost or diminished in affected areas. * Myelinopathy, or "demyelinating polyneuropathy", is due to a loss of myelin (or of the Schwann cells that make and contain it). This demyelination slows down or completely blocks the conduction of action potentials through the axon of the nerve cell. The most common cause is acute inflammatory demyelinating polyneuropathy (AIDP, the most common form of Guillain–Barré syndrome), although other causes include chronic inflammatory demyelinating polyneuropathy (CIDP), genetic metabolic disorders (''e.g.'', leukodystrophy), and toxins. * Neuronopathy is the result of destruction of peripheral nervous system (PNS) neurons. They may be caused by motor neurone diseases, sensory neuronopathies (''e.g.'', Herpes zoster), toxins, or autonomic dysfunction. Neurotoxins such as the chemotherapy agent vincristine may cause neuronopathies. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Polyneuropathy」の詳細全文を読む スポンサード リンク
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