[ Neuromedicine ] Multiple sclerosis 1

Multiple sclerosis – definition

Chronic autoimmune inflammation and demyelination of the CNS.

Multiple sclerosis – sex ratio

Female more than male (2:1).

Multiple sclerosis – age of onset

Females 20 to 35 years (earlier), males 35 to 45 years.

Multiple sclerosis – genetic associations

HLA-DRB1*15, IL2RA, and IL7RA.

Multiple sclerosis – geographic risk

Areas away from the equator (low vitamin D level).

Multiple sclerosis – environmental factors

Viruses (EBV, HHV-6), geography, and diet (obesity).

Multiple sclerosis – pathogenesis

T lymphocytes, B lymphocytes, and the innate immune system, affecting both white and gray matter.

Multiple sclerosis – active disease

Relapse or new MRI activity.

Multiple sclerosis – progressive disease

Degenerative disease with little or no benefit from drugs.

Relapsing remitting MS (RRMS) – frequency and prognosis

Most common type (85 to 90%) with the best prognosis.

Relapsing remitting MS – pattern

Relapses (attacks) with partial or complete recovery.

Relapsing remitting MS – partial recovery means

Decline in function (increased disability score).

Secondary progressive MS (SPMS) – how often it develops

In about 50% of RRMS patients within 10 to 20 years.

MS pathology – cells attacked

Oligodendrocytes.

MS pathology – hallmark

Plaque formation.

MS plaques – locations

Optic nerve (CN II), brain, spinal cord, and brainstem, in both white and gray matter.

MS – demyelination of the spinal cord pyramidal tract

Causes UMN signs and symptoms.

MS symptoms – onset tempo

Develop within hours to days (not sudden or chronic).

MS – most common presenting symptom

Optic neuritis.

MS – motor signs

UMN signs.