The investigators conduct this study to clarify the clinical features and to evaluate the prevalence of anti-nodal/paranodal antibodies of patients with combined central and peripheral demyelination (CCPD) .

The investigators will review the clinical manifestation, laboratory test results, electrophysiological examination and neuroimaging findings of patients with CCPD. And we will detect antibodies to aquaporin 4(AQP4), myelin oligodendrocyte glycoprotein (MOG), neurofascin-155 (Nfasc155), neurofascin-186 (Nfasc186), and myelin-associated glycoprotein (MAG) in patients with CCPD.

Inclusion Criteria:

1. T2 high-signal intensity lesions in the brain or spinal cord on MRI, or visual-evoked potentials(VEPs) abnormalities.
2. conduction delay, conduction block, temporal dispersion or F-wave abnormalities, suggesting peripheral demyelinating neuropathy regarding nerve conduction studies (NCS).

Exclusion Criteria:

1. infectious diseases(e.g., human T lymphocyte trophic virus type1-associated myelopathy, syphilis, neuroborreliosis, HIV infection or progressive multifocal leukoencephalopathy)
2. pre-existing inflammatory diseases (e.g., sarcoidosis, Behçet's disease, Sjögren's syndrome, vasculitis or other collagen diseases)
3. mitochondrial disease
4. metabolic/toxic diseases (e.g., vitamin deficiency, amyloidosis, chronic alcoholism, diabetes mellitus or subacute myelo-opticoneuropathy due to clioquinol intoxication
5. cervical spondylotic myelopathy
6. syringomyelia
7. spinocerebellar degeneration
8. multiple myeloma, other tumors
9. inherited diseases (e.g., leucodystrophies)
10. cerebrovascular disease
11. non-specific lesions on T2-weighted MRI (e.g., leucoaraiosis).

Patients who have combined central and peripheral demyelination