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Neuromyelitis optica (NMO), also known as Devic's disease or Devic's syndrome, is a heterogeneous condition consisting of the simultaneous inflammation and demyelination of the optic nerve (optic neuritis) and the spinal cord (myelitis). It can be monophasic or recurrent. Currently at least two different causes are proposed based on the presence of autoantibodies against AQP4. AQP4+ NMO is currently considered an autoimmune disease (autoimmune astrocytopathy,〔Claudia F. Lucchinetti et al. The Pathology of an Autoimmune Astrocytopathy: Lessons Learned from Neuromyelitis Optica. Brain Pathology Volume 24, Issue 1, pages 83–97, January 2014, DOI: 10.1111/bpa.12099〕 or autoimmune astrocytic channelopathy) in which a person's own immune system attacks the astrocytes of the optic nerves and spinal cord. The cause of the AQP4- variants is unknown. Although inflammation may also affect the brain, the lesions are different from those observed in the related condition, multiple sclerosis. Spinal cord lesions lead to varying degrees of weakness or paralysis in the legs or arms, loss of sensation (including blindness), and/or bladder and bowel dysfunction. Devic's disease is now studied along a collection of similar diseases called "Neuromyelitis optica spectrum diseases".〔Wingerchuk et al. International consensus diagnostic criteria for neuromyelitis optica spectrum disorders. Neurology. 2015 Jun 19. pii: 10.1212/WNL.0000000000001729. PMID 26092914〕 Some cases of this spectrum resemble multiple sclerosis (MS) in several ways, but require a different course of treatment for optimal results.〔 In 2004, NMO-IgG (currently known as Anti-AQP IgG) was first described leading to the distinction between positive and negative cases. In Anti-AQP positive variants, CNS astrocytes, which are the basis for the glymphatic system are the target of the autoimmune attack. NMO-IgG-negative cases are less understood. It seems currently that astrocytes are spared in these IgG negative cases〔Ikeda K. et al. Severe demyelination but no astrocytopathy in clinically definite neuromyelitis optica with anti-myelin-oligodendrocyte glycoprotein antibody. Mult Scler. 2014 Sep 25. pii: 1352458514551455, PMID 25257613〕 ==Signs and symptoms== The main symptoms of Devic's disease are loss of vision and spinal cord function. Optic neuritis may manifest as visual impairment with decreased visual acuity, although visual field defects, or loss of color vision may occur in isolation or prior to formal loss of acuity. Spinal cord dysfunction can lead to muscle weakness, reduced sensation, or loss of bladder and bowel control. The typical patient has an acute and severe spastic weakness of the legs (paraparesis) or all four limbs (quadriparesis) with sensory signs, often accompanied by loss of bladder control. 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「Neuromyelitis optica」の詳細全文を読む スポンサード リンク
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