This progressive loss of the fatty myelin sheath surrounding the nerves in the affected spinal cord occurs for unclear reasons following infections or due to multiple sclerosis. Infections may cause<unk>  through direct tissue damage or by immune-mediated infection-triggered tissue damage. The lesions present are usually inflammatory. Spinal cord involvement is usually central, uniform, and symmetric in comparison to multiple sclerosis which typically affects the cord in a patchy way and the lesions are usually peripheral. The lesions in acute<unk>  are mostly limited to the spinal cord with no involvement of other structures in the central nervous system. Longitudinally extensive<unk>  A proposed special clinical presentation is the "longitudinally extensive<unk> " (LETM), which is defined as a<unk>  with a spinal cord lesion that extends over three or more vertebral segments. The causes of LETM are also heterogeneous and the presence of MOG auto-antibodies has been proposed as a diagnostic biomarker.
Transverse myelitis
Lhermitte's sign
Vascular myelopathy
Acute flaccid myelitis
Amyotrophic lateral sclerosis
Surfer's myelopathy
CMV polyradiculomyelopathy
Primary lateral sclerosis