Acute necrotizing myelitis
The original description of necrotizing myelitis was made in men, rather older than most cases of transverse myelitis, with slowly progressive lumbar cord disease occurring in association with chronic respiratory disease (Foix and Alajounanine 1926). The term ‘acute necrotizing myelitis’ can reasonably be applied to patients developing severe inflammation of the thoracic or spinal cord, in whom flaccid areflexic paraplegia with anaesthesia and loss of sphincter control progresses rapidly over hours. Inflammation is sufficient to cause severe pain with meningism and systemic symptoms, including pyrexia. The clinical presentation suggests compression, and contrast radiology or imaging often reveals a swollen cord with spinal block. Since the cerebrospinal fluid shows a marked polymorphonuclear pleocytosis, raised protein and lowered glucose concentrations, these patients are frequently thought to have pyogenic or tuberculous infection of the central nervous system and are treated with appropriate antimicrobial therapy. In some cases surgical exploration is undertaken to exclude intraspinal abscess. Because of the possibility of infection, there is often a reluctance to use corticosteroids, but the course of acute necrotizing myelitis can be significantly influenced by high-dose intravenous methylprednisolone. Acute necrotizing myelitis has an appreciable mortality, but in survivors the systemic features resolve within weeks, leaving significant handicap and disability. Several organisms have been implicated in the aetiology of acute necrotizing myelitis and it is also described after rabies vaccination, as a complication of acute lymphocytic leukaemias, lymphoma, hypernephroma and other forms of carcinoma, and in acquired immunodeficiency syndrome.