<unk>  term has been inconsistently used at different times. Currently, the commonly accepted international standard for the clinical case definition is the one published by the International Pediatric MS Study Group, revision 2007. Given that the definition is clinical, it is currently unknown if all the cases with<unk>  are positive for anti-MOG autoantibody, but in any case, it seems strongly related to<unk>  diagnosis. Differential diagnosis Multiple sclerosis While<unk>  and MS both involve autoimmune demyelination, they differ in many clinical, genetic, imaging, and histopathological aspects. Some authors consider MS and its borderline forms to constitute a spectrum, differing only in chronicity, severity, and clinical course, while others consider them discretely different diseases. Typically,<unk>  appears in children following an antigenic challenge and remains monophasic. Nevertheless,<unk>  does occur in adults, and can also be clinically multiphasic. Problems for differential diagnosis increase due to the lack of agreement for a definition of multiple sclerosis. If MS were defined just by the separation in time and space of the demyelinating lesions as McDonald did, it would not be enough to make a difference, as some cases of<unk>  satisfy these conditions. Therefore, some authors propose to establish the separation line in the shape of the lesions around the veins, being therefore "perivenous vs. confluent demyelination". Acute hemorrhagic Leukoencephalitis in a patient with Multiple sclerosis. The pathology of<unk>  is very similar to that of MS with some differences. The pathological hallmark of<unk>  is perivenular inflammation with limited "sleeves of demyelination". Nevertheless, MS-like plaques (confluent demyelination) can appear Plaques in the white matter in MS are sharply delineated, while the glial scar in<unk>  is smooth. Axons are better preserved in<unk>  lesions. Inflammation in<unk>  is widely<unk>  and ill-defined, and finally, lesions are strictly perivenous, while in MS they are disposed around veins, but not so sharply. Nevertheless, the co-occurrence of perivenous and confluent demyelination in some individuals suggests pathogenic overlap between<unk>  and multiple sclerosis and misclassification even with biopsy or even postmortem<unk>  in adults can progress to MS Multiphasic<unk><unk>  When the person has more than one demyelinating episode of<unk> , the disease is then called recurrent<unk><unk>  or multiphasic<unk><unk>  (MDEM). It has been found that anti-MOG auto-antibodies are related to this kind of<unk>  Another variant of<unk>  in adults has been described, also related to anti-MOG auto-antibodies, has been named fulminant<unk><unk> , and it has been reported to be clinically<unk> , but showing MS-like lesions on autopsy. It has been classified inside the anti-MOG associated inflammatory demyelinating diseases. Acute hemorrhagic leukoencephalitis Acute hemorrhagic leukoencephalitis (AHL, or AHLE), acute hemorrhagic<unk>  (AHEM), acute necrotizing hemorrhagic leukoencephalitis (ANHLE), Weston-Hurst syndrome, or Hurst's disease, is a hyperacute and frequently fatal form of<unk> . AHL is relatively rare (less than 100 cases have been reported in the medical literature ), it is seen in about 2% of<unk>  cases, and is characterized by necrotizing vasculitis of venules and hemorrhage, and edema. Death is common in the first week and overall mortality is about 70%, but increasing evidence points to favorable outcomes after aggressive treatment with corticosteroids, immunoglobulins, cyclophosphamide, and plasma exchange. About 70% of survivors show residual neurological deficits, but some survivors have shown surprisingly little deficit considering the magnitude of the white matter affected. This disease has been occasionally associated with ulcerative colitis and Crohn's disease, malaria, sepsis associated with immune complex deposition, methanol poisoning, and other underlying conditions. Also anecdotal association with MS has been reported Laboratory studies that support diagnosis of AHL are: peripheral leukocytosis, cerebrospinal fluid (CSF) pleocytosis associated with normal glucose and increased protein. On magnetic resonance imaging (MRI), lesions of AHL typically show extensive T2-weighted and fluid-attenuated inversion recovery (FLAIR) white matter hyperintensities with areas of hemorrhages, significant edema, and mass effect.
Acute disseminated encephalomyelitis
Acute flaccid myelitis
Viliuisk encephalomyelitis
Saint Louis encephalitis
Powassan encephalitis
La Crosse encephalitis
Eastern equine encephalitis
Bickerstaff brainstem encephalitis