Multiple Sclerosis

Question 1

Multiple Sclerosis (MS)

Answer 1

Progressive autoimmune disorder where immune system attacks oligodendrocytes in the CNS
The degradation of myelin results in a breakdown of communication between neurons
Can form at any sites within the CNS and symptoms depend on lesion location
Gray matter can also be involved in early stages

Question 2

Epidemiology

Answer 2

Peak onset 20-40 years of age
2-5% have onset before age 18
Onset can be anywhere from 11 months to 72 years
90-95% experience an average life expectancy

Question 3

Genetic factors

Answer 3

30% concordance rate in identical twins
Relatives of patients with MS are 6-8 times more likely
More common in women (2.5:1)
Women experience onset 5 years earlier

Question 4

Causes

Answer 4

Definitive cause is still unknown
Best guesses: A viral/retroviral infection, or response to a chronic infection

Question 5

Characteristics

Answer 5

Defined by experiences of relapses and disease progression

Question 6

Relapses

Answer 6

Worse periods of neurological symptoms caused by acute inflammatory demyelination

Question 7

Disease progression

Answer 7

Individuals will experience progressive disability due to chronic demyelination, gliosis, and axonal loss overtime

Question 8

Diagnosis

Answer 8

Symptom presentation is heterogeneous and there is no definitive diagnostic test
Must have objective evidence of at least 2 clinical attacks with MRI findings in at least 2 separate areas of CNS
Must have evidence that the attacks/lesions occurred at different time points
Must rule out other potential causes

Question 9

Cognitive impairment

Answer 9

Around 40-65% of patients with MS have cognitive impairment
Related to damaged or destroyed white matter tracks resulting in diffuse white matter changes

Question 10

Domains most often impacted:

Answer 10

Processing speed and attention
Learning and memory
Executive functioning