Multiple sclerosis, infections and toxins

Question 1

Incidence of MS

Answer 1

30-80 per 100000 in Canada

Question 2

Prevalence of MS in the world

Answer 2

depends on where you grew up and not where you live; more prevalent in countries with higher socioeconomic status and less prevalent in countries with warmer climates

Question 3

Definition of MS

Answer 3

an autoimmune demyelinating (i.e. immune system attacks white matter) disease

Question 4

Defining feature of MS

Answer 4

neurological episodes varying in time and space with a background of progressive decline

Question 5

Groups vulnerable to MS

Answer 5

2-3x more common in females and 5x risk in those who have siblings with MS

Question 6

Peak of onset and disability of MS

Answer 6

onset peaks in 30s-50s while disability peaks in 60s

Question 7

Symptoms experienced during acute episodes in MS

Answer 7

focal weakness, paresthesias, monocular vision loss, diplopia, dysphagia, dysarthria, ataxia, bladder dysfunction

Question 8

Chronic impairments in MS

Answer 8

fatigue, gait instability, focal spasticity, cognitive slowing, attention and memory problems, executive dysfunction

Question 9

Paresthesias

Answer 9

tingling sensation caused by sensory change

Question 10

Diplopia

Answer 10

double vision or seeing two images of a single object

Question 11

Dysphagia

Answer 11

difficulty swallowing

Question 12

Pathophysiology of MS

Answer 12

immunopathologic mechanism wherein lymphocytes and macrophages in immune system attack myelin on axons, forming new lesions along with old lesions in glial scar tissue

Question 13

5 brain structures most affected in MS

Answer 13

cortex (periventricular), optic nerves, brainstem, spinal cord, cerebellum

Question 14

How does epstein-barr virus cause MS?

Answer 14

increase in NfL, a protein found in blood and a biomarker of white matter damage, after EBV infection

Question 15

2 ways to diagnose MS

Answer 15

detecting symptomatic lesions separated in time and space through MRI of brain and spinal cord; cerebrospinal fluid (spinal tap)

Question 16

Course of MS

Answer 16

possibly years between initial minor symptom and progression

Question 17

Most common prognosis or pattern of MS

Answer 17

relapsing-remitting with an average of 1-2 attacks per year

Question 18

3 treatments for MS

Answer 18

corticosteroids for acute attacks; anti-CD20 monoclonal antibodies or MS-specific drugs to regulate immune system (e.g. alemtuzumab, ocrelizumab); EBV-specific therapies

Question 19

2 kinds of bacterial infections

Answer 19

bacterial meningitis and brain abscess

Question 20

Bacterial meningitis

Answer 20

inflammatory reaction in the meninges (layer between the brain and skull) leading to fever, headache, stiff neck

Question 21

Brain abscess

Answer 21

accumulation of pus (ring enhancement in MRI) in the brain that typically starts due to an infection in the nose/sinus

Question 22

Treatments for bacterial infections

Answer 22

antibiotics

Question 23

4 types of viral infections

Answer 23

viral meningitis (almost never fatal), herpes simplex encephalitis, HIV, prion diseases

Question 24

Herpes simplex encephalitis

Answer 24

attacks the medial-temporal lobe (bilateral) that leads to memory problems and personality changes; often misdiagnosed as psychosis

Question 25

Prion diseases (e.g. Creutzfeldt-Jakob disease)

Answer 25

a rare viral infection that one can get from eating infected meat but is typically idiopathic; leads to the most rapid progression of dementia (weeks-months)

Question 26

5 hypothesized pathophysiologies of SARS-CoV-2

Answer 26

neuroinflammation with antibody production; factors of susceptibility (e.g. genetics); limited presence of spike protein or viral particles; damaged blood vessels; unexplainable neuronal injury

Question 27

Unresolved questions about neuropsychiatric effects of COVID-19

Answer 27

weak/inconsistent relationship with disease severity; symptoms and impairments not unique to COVID; symptoms without anosmia (loss of smell); pre-illness psychosocial risk factors

Question 28

4 kinds of toxins

Answer 28

alcohol, recreational drugs, poisons and venoms, heavy metals

Question 29

Wernicke-Korsakoff’s Encephalopathy

Answer 29

excessive alcohol consumption leads to poor diet, nutrition (thiamine) deficiency, memory problems (e.g. episodic, retrograde amnesia, confabulation, except for procedural)

Question 30

Anoxic brain injury

Answer 30

prevents oxygen from binding to red blood cells and getting into the brain