Multiple sclerosis (MS) is considered to be an autoimmune disease of the central nervous system (CNS) that in many patients first presents clinically as optic neuritis. The relationship of optic neuritis to MS is not well understood. We have generated novel T cell receptor (TCR) transgenic mice specific for myelin oligodendrocyte glycoprotein (MOG). MOG-specific transgenic T cells are not deleted nor tolerized and are functionally competent. A large proportion (>30%) of MOG-specific TCR transgenic mice spontaneously develop isolated optic neuritis without any clinical nor histological evidence of experimental autoimmune encephalomyelitis (EAE). Optic neuritis without EAE could also be induced in these mice by sensitization with suboptimal doses of MOG. The predilection of these mice to develop optic neuritis is associated with higher expression of MOG in the optic nerve than in the spinal cord. These results demonstrate that clinical manifestations of CNS autoimmune disease will vary depending on the identity of the target autoantigen and that MOG-specific T cell responses are involved in the genesis of isolated optic neuritis. (+info)
Optic neuritis and retinal vasculitis as primary manifestations of systemic lupus erythematosus.
(42/359)
Systemic lupus erythematosus (SLE) is a common multisystem disorder. However, retinal vasculitis as a primary manifestation of SLE is uncommon, accounting for only 4% of causes of retinal vasculitis. The postulated mechanism appeared to be vaso-occlusion of the retinal arterioles by thrombosis, with resultant ischaemia. Optic neuropathy in SLE is also rare, with a prevalence of 1%. This is a case report of a young lady who presented to us with retinal vasculitis as her initial presentation of SLE. Interestingly, the pathologic mechanism appeared to be inflammatory and not vaso-occlusive. (+info)
Subacute myelo-optic neuropathy and clioquinol. An epidemiological case-history for diagnosis.
(43/359)
Between about 1955 and 1970, some 100,000 Japanese were diagnosed as having subacute myelooptic neuropathy (SMON), a new disease characterized by abdominal and neurological manifestations, the former nearly always preceding the latter. Circumstantial evidence obtained in 1969-70 suggested that SMON might have been caused by clioquinol (CQL), a gastrointestinal disinfectant, and led to the suspension of further sales of CQL in Japan. However, several inconsistencies for the CQL theory of SMON have now emerged; first, CQL had been widely used in Japan for nearly 20 years before SMON occurred. Secondly, the SMON epidemic began to subside several months before CQL sales were suspended. Thirdly, a large proportion of SMON patients--probably about one-third and possibly more--had not taken CQL within six months of the onset of the disease (the modal interval between first taking CQL and the onset of SMON being about three weeks, and more than 100 days in only 4% of SMON patients); of the remaining two-thirds or so, many had taken CQL as part of the treatment of the first (that is, abdominal) symptoms of SMON itself. Fourthly, there was no dose-response relationship. Finally, SMON rarely, if ever, occurred outside Japan. CQL could, however, have been involved in the causation of SMON as an optional enhancer of some other necessary cause; the history of post-war environmental pollution in Japan is compatible with this hypothesis. Over-readiness to accept postulated toxic effects of medicines and chemicals as proven is likely to do at least as much harm as good to individual and community health. (+info)
Intracanalicular optic nerve meningioma: a serious diagnostic pitfall.
(44/359)
We describe six cases of cannalicular optic nerve meningioma in which the diagnosis was missed for more than 1 year after the onset of symptoms. Clinical features led to a misdiagnosis of optic neuritis in all cases. Although atypical clinical progression led to further imaging studies, they did not provide the diagnosis because of inappropriate imaging protocols. Diagnosis was eventually made on the basis of high-spatial-resolution contrast-enhanced MR findings. Radiologists should have a high suspicion for the diagnosis of optic canal meningioma in patients with unexplained visual loss, particularly when visual loss is progressive. Investigation in these cases should include high-spatial-resolution MR imaging of the orbit before and after contrast medium administration, and fat suppression should be used in combination with contrast enhancement whenever possible. (+info)
Spatial vision in visually asymptomatic subjects at high risk for multiple sclerosis.
(45/359)
OBJECTIVE: To investigate the state of spatial vision in visually asymptomatic subjects at high risk for multiple sclerosis. METHODS: Fifteen subjects suffering a first neurological episode suggestive of multiple sclerosis in clinical presentation, immunological profile, and magnetic resonance imaging, were examined with a new, sensitive test of spatial vision, rarebit perimetry. None had symptoms or signs of optic neuropathy. RESULTS: Results of rarebit perimetry were significantly worse than those of 15 age matched normal controls (p=0.01); seven patients (47%) were outside normal limits. One patient only obtained abnormal results in high pass resolution perimetry. CONCLUSIONS: Rarebit perimetry may help to close the sensitivity gap between clinical examinations and neuroimaging. (+info)
Methylprednisolone increases neuronal apoptosis during autoimmune CNS inflammation by inhibition of an endogenous neuroprotective pathway.
(46/359)
Optic neuritis is one of the most common clinical manifestations of multiple sclerosis (MS), a chronic inflammatory disease of the CNS. High-dosage methylprednisolone treatment has been established as the standard therapy of acute inflammation of the optic nerve (ON). The rationale for corticosteroid treatment lies in the antiinflammatory and immunosuppressive properties of these drugs, as shown in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. To investigate the influence of methylprednisolone therapy on the survival of retinal ganglion cells (RGCs), the neurons that form the axons of the ON, we used a rat model of myelin oligodendrocyte glycoprotein (MOG)-induced EAE. Optic neuritis was diagnosed by recording visual evoked potentials, and RGC function was monitored by measuring electroretinograms. Methylprednisolone treatment significantly increased RGC apoptosis during MOG-EAE. By Western blot analysis, we identified the underlying molecular mechanism: a suppression of mitogen-activated protein kinase (MAPK) phosphorylation, which is a key event in an endogenous neuroprotective pathway. The methylprednisolone-induced inhibition of MAPK phosphorylation was calcium dependent. Hence, we provide evidence for negative effects of steroid treatment on neuronal survival during chronic inflammatory autoimmune disease of the CNS, which should result in a reevaluation of the current therapy regimen. (+info)
Combination of high-dose intravenous immunoglobulins and itraconozole in treating chronic mycotic demyelinating optic neuritis.
(47/359)
Mycotic demyelinating optic neuritis is a neurological disorder of the visual system caused by mycotoxins released by indoor toxic molds. Although the health effect of indoor toxic mold on the population worldwide is now one of the "emerging diseases", its involvement in chronic demyelinating optic neuritis has not been reported. Most of the neurological and immunologic abnormalities associated with toxic mold mycotoxins are very difficult to treat successfully, especially neural demyelination of the central and peripheral nervous systems. This paper presents the case of a 42-year-old white female, in whom chronic demyelinating optic neuritis with persistent visual defects due to chronic exposure to toxic molds was diagnosed at the age of 34 years. In spite of all the therapeutic services given to her for over 8 years, her illness persisted and was difficult to treat. However, we successfully treated her with a combination of intravenous immune globulin (IVIG) and itraconozole (Sporanox) when all other treatment modalities failed. This is probably the first report where persistent toxic mold-induced neurological and immunologic disorders were successfully treated with a combination of itraconozole and IVIG. (+info)
Acute optic neuritis associated with immunization with the CNS myelin proteolipid protein.
(48/359)
Optic nerve tissue for SJL/J mice immunized with the central nervous system (CNS) myelin-specific proteolipid protein (PLP) was examined for histopathologic evidence of optic neuritis. Optic nerves isolated 17 d after immunization with PLP revealed an interstitial and submeningeal inflammatory infiltrate consisting of neutrophils and monocytes. In all cases, histologic evidence of optic nerve involvement correlated serologically with the presence of circulating anti-PLP antibodies. Control animals had no histopathologic evidence of disease or anti-PLP antibody. In many respects, the observed histopathologic profile of PLP-induced optic neuritis is similar to that associated with human inflammatory demyelinating diseases such as multiple sclerosis (MS). Because optic neuritis frequently is associated with some of the earliest clinical symptoms of MS, the acute nature of optic nerve involvement in this animal model suggests that immune recognition of the myelin PLP may play a significant role in the pathophysiology of optic nerve damage associated with sensitization to CNS-specific antigens. (+info)