Overview of symptoms, pathogenesis, diagnosis, treatment, and prognosis of various acquired polyneuropathies

Polyneuropathy means a lot of diseases affecting peripheral nerves showing roughly the same areas on both sides of the body, featuring weakness, numbness, and burning pain [1]. Pathogenesis causing polyneuropathy usually begins in the hands and feet and progresses to the arms and legs [1]. Sometimes it can involve other parts of the body such as the autonomic nervous system. Uncountable causes can induce acute or chronic polyneuropathy, so finding the original cause is most important for the treatment of polyneuropathy. Polyneuropathies are classified in different ways depending on cause, presentation, or classes of polyneuropathy (for example, the axon, the myelin sheath, or the cell body). Among these classifications, the classification based on classes of polyneuropathy can explain the pathogenesis and symptoms at the same time. Polyneuropathy in the axon is called distal axonopathy which is the result of interrupted function of the peripheral nerves and the most common response of neurons to metabolic or toxic disturbances, such as diabetes, kidney failure, connective tissue disease, deficiency syndrome, alcoholism, chemotherapy, and so on. People with distal axonopathy frequently present with sensorimotor disturbances. Disease in the myelin sheath is myelinopathy characterized with a loss of myelin or of the Schwann cells. This demyelination disturbs the conduction of action potentials through the axon of the nerve cells. Among various diseases causing myelinopathy, the most common one is acute inflammatory demyelinating polyneuropathy (AIDP). Damage of neurons in the peripheral nervous system results in neuronopathy. Neuronopathies can Corresponding Author: Seong-Ho Koh Department of Neurology, Hanyang University Guri Hospital, Hanyang University College of Medicine, 153 Gyeongchun-ro, Guri 11923, Korea Tel: +82-31-560-2267 Fax: +82-31-560-2267 E-mail: ksh213@hanyang.ac.kr