Multiple sclerosis (MS) is the most prevalent chronic inflammatory disease of the central nervous system. This incurable disease affects more than 2 million people worldwide with about 75% of cases occurring in women.
MS is a demyelinating disease characterized by multifocal and temporally scattered central nervous system (CNS) damage which leads to axonal damage. Exogenous, environmental, and genetic factors contribute to the development of MS and the correlations of these factors are still being widely studied. Depending on the severity of signs and symptoms, MS can be described as benign or malignant.
Clinical courses of MS can be described as :
- Relapsing-remitting multiple sclerosis (RRMS)
- Secondary progressive multiple sclerosis (SPSM)
- Primary progressive multiple sclerosis (PPMS
- Progressive -relapsing multiple sclerosis (RPMS)
MS diagnosis is based on McDonald’s diagnostic criteria, which link clinical manifestation with characteristic plaque-like lesions demonstrated by magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) analysis, and visually evoked potentials. Common presenting syndromes of MS include monocular visual loss due to optic neuritis, limb weakness or sensory loss due to transverse myelitis, double vision due to brainstem dysfunction, or ataxia due to a cerebellar lesion. Fully or partially reversible episodes of neurological disability usually last days to weeks. The most important diagnostic and prognostic MS biomarker is MRI, which is currently the only technique to interrogate the entire CNS in vivo. By MRI, inflammatory demyelination is easily visible, and neurodegeneration is detectable by measuring the brain’s size or spinal cord.
As of October 2017, the US Food and Drug Administration has approved 15 medications for modifying the course of MS:
- 5 preparations of interferon beta;
- 2 preparations of glatiramer acetate;
- Monoclonal antibodies natalizumab, alemtuzumab, daclizumab, and ocrelizumab (the first B-cell targeted therapy);
- Chemotherapy mitoxantrone
- Small-molecule oral agents fingolimod, dimethyl fumarate, and teriflunomide.
Dalfampridine has been approved as a symptomatic therapy to improve walking speed. All treatments are approved for relapsing-remitting MS and reduce the likelihood of developing new white matter lesions, clinical relapses, and stepwise accumulation of disability.
A great deal of work has also revolved around tissue repair and protection. Several approved drugs (targeting, for example, nuclear hormone receptor, histaminic, cholinergic (muscarinic), and adrenergic pathways) are being tested for remyelination or myelin protection. Axonal protection is also actively being examined.
- Kamińska J, Koper OM, Piechal K, Kemona H. Multiple sclerosis – etiology and diagnostic potential. Postepy Hig Med Dosw (Online). 2017 Jun;71(0) 551-563. doi:10.5604/01.3001.0010.3836. PMID: 28665284.
- Reich DS, Lucchinetti CF, Calabresi PA. Multiple Sclerosis. N Engl J Med. 2018 Jan 11;378(2):169-180. doi: 10.1056/NEJMra1401483.