Multiple Sclerosis (MS) Flashcards
Function and location of neurons (oligodendrocytes, ependymal cells, astrocytes, microglia)
Oliogdendrocytes: CNS myelination
Ependymal Cells: line the ventricles, circulate in CSF
Astrocytes: throughout parenchyma, formulate BBB
Microglia: phagocytes in CNS, very close to blood vessels
Etiology/Pathogenesis
Autoimmune disorder
acute inflammation and demyelination of CNS (like GBS, only CNS involvement)
3 patterns of MS
pattern 1: macrophage mediated demyelination
pattern 2: immunoglobulin depositions and complement activities within the plaques
pattern 3: primary oligodendropathy (more detrimental than demyelination)
- IDed by Leucchinetti
Fibrous Gliosis
“Sclerotic Plaque” formation
disrupted BBB –> WBC/monocytes/macrophages enter the brain –> intra + extracellular swelling –> scarring/sclerotic plaques –> secondary axonal degeneration
T2 v T1 imaging on MRI
T2 - presence of lesions on gross pathology (bright white signal)
T1 - visualization of axonal dropout (during acute phase, could be secondary to edema and resolve
age of onset, gender, race, geographics
Age of onset: 15-50 (pediatric = 2-5%)
Gender: F>M
Race: Caucasians
Geography: higher prevalence further from equator (incidence highest in UK)
Cause of MS: genetic or viral?
unknown, but both thought to be involved
EBV: MS pt more likely (+) for EBV
Types of MS (based on clinical presentation)
- Relapsing/Remitting MS (RR-MS)
- Primary Progressive MS (PP-MS)
- Secondary Progressive MS (SP-MS)
- Progressive Relapsing (PR-MS)
RR-MS
85%- most common
episodes of exacerbation + recovery (almost full) –> Accumulation of deficits
Exacerbations not always in the same place
*Subtype = benign RR-MS = infrequent relapse rate (years in between replaces)
PP-MS
10%
male more likely
steady degredation/decline (no clear relapse + recovery rate)
SP-MS
> 50% RR-MS turn into SP-MS >15yrs after diagnosis
now pt’s on a downward trend- some relapses+ recovery, but less recovery before next relapse
PR-MS
5%
a couple small relapse + slight recovery episodes, then decline smooths off
looks very similar to PP-MS; difference = slight recovery at the beginning of PR-MS
Clinically Isolated Syndrome (CIS)
1st sign of anything- first demyelinated episode
50-80% conversion risk to MS
treatment with immunosuppressant drugs (IVIG- prevent progression to CDMS)
evidence is seen on MRI- ONLY 1 lesion!
Clinically Definite MS (CDMS)
Multiple lesions in the CNS on MRI
Evidence of >/= 2 distinct episodes (MD will have to figure this out with interview)
Signs and Symptoms: Visual system
visual = common 1st clinical exacerbation (although sx vary)
- worsening throughout the day
- optomologist doesn’t see anything on eye exam
Signs and symptoms: non-visual
- weakness (rapid onset of shutdown in particular function)
- tremor
- paresthesias
- incoordination
- cognitive complaints
- fatigue
insidious onset! pt may not even pay attention to it
Prognosis
- AD use
- non-ambulatory status
- life-span (pre and post IMD)
AD use: 50% with dx >/= 15yrs
Non-ambulatory status: 40% with an attack that renders them non-ambulatory
Life span pre IMD: 15-40yrs
Life span post IMD: similar to normal population (mortality by other diseases, not MS)
*depends on relapse rate; RR-MS = best prognosis
When a pt complains of cognitive symptoms (impaired memory/not thinking clearly), do they actually have these issues?
YES!- seen biologically
treat pt with TBI techniques
cognitive issues in large % of MS and non related to severity
Medical Management during acute exacerbation
High does steroids for 3-5 days via IV (taper with oral)
*prevention of inflammation
Medical management: long term immune modulating drugs:
- Interferons beta 1a/1b (IFNB)
- Glatiramer Acetate (copaxone)
- IVIG- prevention of CIS to CDMS; does nothing to RR-MS
- Plasma exchange (only for certain subtypes)
- Texadera
Interferons beta 1a/1b (IFNB)
- dosage
- administration
- subtypes useful in
1a = ayonex --> 1x/wk 1b = betaseron --> every other day
- injection into muscle
- subtypes: RR-MS, CIS (50% reduced conversion to CDMS), not useful in PP-MS
Glatiramer Acetate (copaxone)
- dosage
- administration
- subtypes useful in
administered every day
injection into muscle
Subtypes: RR-MS, NOT in PP-MS
*higher reduction in relpase than IFNB, but still not preferred due to every day injection
Studies examining IFNB and copaxone- effect on prognosis
included MS pts with at least 2x/year relapse rate and RR-MS for 5 years
- found decreased accumulation of lesion size and number of relapses that the pt has in a 1 or 2yr period
- huge reduction in rate of relapse
- less lesion load in MRI
- pts able to do more for a longer time
- decreased cognitive defects
Texadera
- adminiatration
- dosage
- side effect
Oral pill
every day
decreases lymphocyte count –> more susceptible to infections
