Demyelination Multiple sclerosis

In multiple sclerosis, which is a demyelinating disease, there is loss of both phospholipids (particularly ethanolamine plasmalogen) and of sphingolipids from white matter. Thus, the lipid composition of white matter resembles that of gray matter. The cerebrospinal fluid shows raised phospholipid levels. 

Multiple sclerosis (MS) is a complex inflammatory disease of the central nervous system (CNS) that is variable in terms of symptoms and presentation. The name refers to two features of the disease multiple describes the number of CNS lesions and sclerosis refers to the demyelinated lesions. Today, these lesions are usually called plaques, rather than scleroses. Although scientific understanding of MS has progressed at a rapid pace, there are still many areas of evolving knowledge. 

Biologic response modifiers (BRMs) are indicated in patients who have failed an adequate trial of DMARD therapy.1 BRMs may be added to DMARD monotherapy (i.e., methotrexate) or replace ineffective DMARD therapy.22 The decision to select a particular agent generally is based on the prescriber s comfort level with monitoring the safety and efficacy of the medications, the frequency and route of administration, the patient s comfort level or manual dexterity to self-administer subcutaneous injections, the cost, and the availability of insurance coverage.23 In general, BRMs should be avoided in patients with serious infections, demyelinating disorders (e.g., multiple sclerosis or optic neuritis) or heart failure.21... 

Uhthoff s phenomenon Acute worsening of multiple sclerosis symptoms on exposure to heat because high body temperatures may exceed the capacitance of the demyelinated nerve and conduction may fail. 

The functional significance of myelin is revealed by the neurological deficits observed in patients with multiple sclerosis. This disorder is caused by the demyelination of neurons in the brain, spinal cord, and optic nerve. The loss of myelin disrupts the normal conduction of impulses along the axons of these neurons and results in weakness, numbness, loss of bladder control, and visual disturbances. 

Multiple sclerosis A disease characterised by the progressive demyelination of CNS neurons and the loss of oligodendrocytes. Cannabinoids may be of benefit in treating MS. 

Adrenoleukodystrophy is an X-linked dysmyelinative disorder caused by mutations in the ABCD1 gene, which encodes the peroxisomal integral membrane ALD protein, a member of the ATP binding cassette transporter family. These mutations result in impaired clearance of plasma very-long-chain fatty acids. Affected males may present with symmetrical distal axonal polyneuropathy, adrenocortical insufficiency or CNS demyelination, while occasional heterozygous women demonstrate deficits suggestive of multiple sclerosis [56]. Manipulation of dietary fatty acid intake has some minimal therapeutic effect, while bone marrow transplantation has diminished deficits in a few patients. (See in Ch. 41.)... 

Multiple sclerosis is the most common demyelinating disease of the central nervous system in humans 641... 

Lucchinetti, C., Bruck, W., Parisi, J. etal. Heterogeneity of multiple sclerosis lesions implications for the pathogenesis of demyelination. Ann. Neurol. 47 707-717, 2000. 

Berger, T., Rubner, P., Schautzer, F. etal. Antimyelin antibodies as a predictor of clinically definite multiple sclerosis after a first demyelinating event. N. Engl J. Med. 349 139-145,2003. 

Oligodendrocytes are present in the CNS as well and wrap around axons to form a myelin sheath. Myelin wraps into concentric layers that spiral around the axon. Gaps in the oligodendrocytes are the nodes of Ranvier, where the membrane maintains contact with extracellular fluid. The nodes serve to propagate the action potential in myelinated axons. Schwann cells perform an analogous function, myelinating axons in the peripheral nervous system. Not all neurons are myelinated, but myelination increases the metabolic efficiency of action potentials. Demyelination of neurons produces deficits in neuronal conduction, as is seen in multiple sclerosis. 

Multiple sclerosis progressive degenerative disease presenting with disseminated demyelination of nerve fibres of the brain and spinal cord Myalgia muscle pain... 

Multiple sclerosis (MS) is a devastating disease of the CNS that produces demyelination and inflammation. It is believed that its pathogenesis involves an immune reaction against various components of the myelin sheath. In a study by Lock et al. (2002), the gene expression patterns of brain lesions obtained during autopsies of MS patients were examined by microarray cluster analysis. A total of 1080 genes (from 7026 represented... 

Neurologic events Infliximab and other agents that inhibit TNF have been associated in rare cases with optic neuritis, seizure, and new onset or exacerbation of clinical symptoms or radiographic evidence of CNS demyelinating disorders, including multiple sclerosis and CNS manifestations of systemic vasculitis. Exercise caution in considering the use of infliximab in patients with pre-existing or... 

Jacobs LD, Beck RW, Simon JH, Kinkel RP, Brownschei-dle CM, Murray TJ et al. Intramuscular interferon beta-1 a therapy initiated during a first demyelinating event in multiple sclerosis. CHAMPS Study Group. N Engl J Med 2000 343(13) 898-904. 

Nervous system (dementia, stroke, epilepsy, extrapyramidal diseases [Parkinson s], demyelinating diseases [multiple sclerosis], neuropathy, myasthenia gravis, psychosis, schizophrenia)... 

Better definition of lesions in demyelinating disorders (e.g., multiple sclerosis) and, therefore, early identification... 

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