Multiple Sclerosis

Excerpt

Multiple sclerosis is a chronic autoimmune disease affecting the central nervous system (CNS) and is characterized by inflammation, demyelination, gliosis, and neuronal loss. This condition manifests with a wide range of neurological symptoms, such as vision impairment, numbness and tingling, focal weakness, bladder and bowel dysfunction, and cognitive impairment.

Pathologically, perivascular lymphocytic infiltrate and macrophages lead to the degradation of myelin sheaths surrounding neurons, causing symptoms that vary depending on lesion location. Clinical symptoms characterized by acute relapses typically appear first in young adults, followed by a gradually progressive course leading to permanent disability within 10 to 15 years.

Multiple sclerosis presents various disease courses and is classified into 7 categories, as outlined below.

1. Relapsing-remitting (RR): This initial onset is observed in 70% to 80% of multiple sclerosis patients and is characterized by the below-mentioned neurological presentation.

   1. New or recurrent neurological symptoms that are consistent with multiple sclerosis

   2. Symptoms lasting 24 to 48 hours

   3. Symptoms developing over days to weeks

1. Primary progressive (PP): This course presents in 15% to 20% of patients and shows a gradual deterioration from onset without relapses.

1. Secondary progressive (SP): Following an initial relapsing-remitting course, this course is marked by a more gradual neurological decline. Superimposed relapses can occur but are not mandatory.

1. Progressive-relapsing (PR): This course involves gradual deterioration with superimposed relapses and is seen in 5% of patients.

Additionally, the following 3 categories are sometimes considered within the spectrum of multiple sclerosis:

1. Clinically isolated syndrome: This is often classified as a single episode of inflammatory CNS demyelination.

1. Fulminant: This is characterized by severe multiple sclerosis with multiple relapses and rapid progression toward disability.

1. Benign: This features an overall mild disability course with rare relapses.

When discussing multiple sclerosis, clinicians commonly focus on the relapsing-remitting course due to its high prevalence among affected patients. Relapses in relapsing-remitting multiple sclerosis often show partial or complete recovery over weeks or months, sometimes without treatment. However, residual symptoms from these relapses, without complete recovery, can accumulate over time and contribute to overall disability. Diagnosis of relapsing-remitting multiple sclerosis typically requires evidence of at least 2 CNS inflammatory events. Although various diagnostic criteria exist for multiple sclerosis, the general principle for diagnosing the relapsing-remitting course involves establishing episodes separated in "time and space."

This entails that episodes must be temporally separated and involve distinct locations within the CNS. A prompt diagnosis of multiple sclerosis enables the timely initiation of disease-modifying therapy, leading to effective management. Treatment goals include decreasing relapses and magnetic resonance imaging (MRI) activity while minimizing permanent disability and addressing various patient concerns such as bladder and bowel dysfunction, depression, cognitive impairment, fatigue, sexual dysfunction, sleep disturbances, and vertigo.