The Washington Manual of Medical Therapeutics helps you diagnose and treat hundreds of medical conditions. Consult clinical recommendations from a resource that has been trusted on the wards for 50+ years. Explore these free sample topics:
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- Multiple sclerosis (MS) is a chronic, progressive, immune-mediated disorder of the CNS, initially characterized by inflammatory demyelination followed later in its course by neurodegeneration.
- Although the disorder is presumed to be autoimmune in nature, the antigen(s) driving the immune response remains unknown.
- Forms of MS include the most common form, relapsing-remitting MS (RRMS), associated with episodic neurologic dysfunction followed by a complete or partial recovery in between episodes. The majority of patients are initially diagnosed with RRMS.
- A less common variant is primary progressive MS (PPMS), a form of the disease characterized by progressive neurologic dysfunction from onset without relapses or remissions.
- Secondary progressive MS (SPMS) is also characterized by a course of progressive neurologic dysfunction but follows an initial relapsing-remitting course.
- The least common form is one of a progressive relapsing course in which patients have a steady, progressive decline from the time of onset with superimposed exacerbations (i.e., worsening).
- Classification is important in that progressive forms of the disease, in general, do not respond to many of the first-line disease-modifying therapies (DMTs) effective in RRMS (e.g., interferon-β) but do respond to other therapies (e.g., ocrelizumab in PPMS).
- Approximately 500,000 patients carry a diagnosis of MS in the United States.
- The worldwide prevalence is estimated at over 2.3 million and growing.
The exact etiology of MS remains unknown. The pathophysiologic pattern of MS is characterized by inflammatory cell infiltration, demyelination, axonal damage, and gliosis culminating in neurodegeneration.