myelitis

1. Inflammation of the spinal cord. 2. Inflammation of the bone marrow. [myel- + G. -itis, inflammation]

- acute necrotizing m. a spinal cord disorder, probably a demyelinating disease, which affects persons of all ages and either sex. Presents with abrupt or more gradual onset with sensory abnormalities and upper motor neuron weakness; soon a reflexic flaccid motor paralysis and sphincter paralysis supervenes, which is permanent. In some, but not all cases, bilateral or unilateral optic neuritis is associated. In the cerebrospinal fluid, the protein is increased, and mononuclear cells are present. After autopsy, the lesion has been identified as a necrotizing hemorrhagic leukomyelitis.

- acute transverse m. acute inflammation and softening of the spinal cord; involves the entire thickness of the spinal cord but of limited longitudinal extent; multiple etiologies.

- ascending m. progressive inflammation involving successively higher areas of the spinal cord.

- bulbar m. inflammation of the medulla oblongata.

- concussion m. traumatic myelopathy.

- demyelinated m. acute multiple sclerosis presenting as a m..

- Foix-Alajouanine m. SYN: subacute necrotizing m..

- funicular m. 1. inflammation involving any of the columns of the spinal cord; 2. SYN: subacute combined degeneration of the spinal cord.

- postinfectious m. spinal cord inflammation that follows a viral infection, usually one of the exanthemas.

- postvaccinal m. spinal cord inflammation that follows vaccination.

- radiation m. SYN: radiation myelopathy.

- subacute necrotizing m. a disorder of the lower spinal cord in adult males resulting in progressive paraplegia. SYN: angiodysgenetic myelomalacia, Foix-Alajouanine m..

- systemic m. inflammation confined to special tracts of the spinal cord.

- transverse m. an inflammatory process involving both gray and white matter of spinal cord.

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my·e·li·tis .mī-ə-'līt-əs n, pl my·e·lit·i·des -'lit-ə-.dēz inflammation of the spinal cord or of the bone marrow

my·e·lit·ic -'lit-ik adj

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n.

1. an inflammatory disease of the spinal cord. The most usual kind (transverse myelitis) most often occurs during the development of multiple sclerosis, but it is sometimes a manifestation of encephalomyelitis, when it can occur as an isolated attack. The inflammation spreads more or less completely across the tissue of the spinal cord, resulting in a loss of its normal function to transmit nerve impulses up and down. It is as though the spinal cord had been severed: paralysis and numbness affects the legs and trunk below the level of the diseased tissue.

2. inflammation of the bone marrow. See osteomyelitis.

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my·eli·tis (mi″ə-liґtis) pl. myeliґtides [myel- + -itis] 1. inflammation of the spinal cord, often part of a more specifically defined disease process. One group of diseases is named according to whether primarily white matter or gray matter is affected (see leukomyelitis and poliomyelitis); another group is defined by whether there is coexistent disease of the meninges (meningomyelitis) or the brain (encephalomyelitis). In practice, the term is also used to denote noninflammatory lesions of the spinal cord; see myelopathy. 2. inflammation of the bone marrow; see osteomyelitis.