Kaplin AI et al. The Neurologist. Diagnosis and management of acute myelopathies. 2005; 11:2-18. Review article
Incidence: 1-8 cases per million per year.
Nosology: idiopathic (most) v. associated with a known inflammatory disease (MS, SLE, Sjogren's, NMO, neurosarcoidosis). In the JHTMC only 20 % recurred, 80 % were monophasic. Regional specificity helps the diagnosis eg. cord plus ON is c/w ON, whereas brain involvement suggests ADEM.
Pathology- depends on process, but all have focal monocyrtic infiltration, into perivascular spaces and astroglial and microglial activation. Gray and white matter of cord both are affected and central cord is often affected. Lupus cases may be associated with a CNS vasculitis OR thrombotic infarct of the cord. Sarcoid has noncaseating granulomas whereas MS has perivascular lymphocyte cuffing mononuclear cell infiltration. Postvaccination TM is described with influenza vaccine and booster hepatitis B. Postinfectious causes have numerous and growing numbers of bacteria and viruses associated including Listeria and HSV. Molecular mimicry, analagous to that seen in GBS after Campylobacter infection, is described with Enterobium vermicularis (pinworm) infection. Superantigen mediated infection (eg. Strep B infection with polyclonal expansion of T cells) is postulated.
NMO and recurrent TM involves humoral abnormal immune function that then activate other components of the immune system. It indicates polyclonal derangement of the immune system. It may not be just autoantibodies, but high levels of circulating antobodies that cause recurrent TM. They may form immune complexes. This occurred with hepB sAg. Several Japanese patients had very high IgE levels (360 v. 52 in MS and 85 in normal controls). They had high IgE to household mites (Dermatophagoides farinae) with antibody deposition in the spinal cord, perivascular lymphocyte cuffing and eosinophilic migration. The recruited eosinophils are thought to have induced the neural injury.
In the JHTMC, elevated IL-6 correlated strongly with disability (unlike MS). IL-6 correlated with nitrous oxide that also correlated with disability.
Predictors of recurrence are multifocal lesions in cord or brain, OCB's in CSF, presence of 14,3,3protein