Multiple Sclerosis Flashcards
Which type of matter is affected in MS
Both gray and white matter
The classic definition stated it was an inflammatory demyelinating disease of white matter however there is clear evidence that this is cortical gray matter involvement as well. GM damage is related to WM damage
classic definition of MS
MS is characterized by recurrent attacks of multi focal sites where multiple episodes are separated by at least 30 days and occur at different sites within the CNS
female to male ratio
2 to 1 but some sources say 4 to 1
Geographic distribution
less incidence in more tropical zones; greater occurrence in temperature zones and Syracuse. This may be a Vitamin D related issue or some kind of virus that can get killed in hotter climates
onset age range of MS
20-50 with peak incidence in late 20s to early 30s (average is 32)
most common race for MS
Caucasians of northern European decent
Three possible factors for cause of MS
genetics
environmental trigger
immune dysfuction
explain the environmental trigger factor
o Found more in temperature zones
Virus can survive in these areas but not in warmer climates
o Lack of Vitamin D during childhood
explain the immune dysfunction factor
o Detected during exacerbations
o Some have T cell abnormalities
o Symptoms of MS typically worsen during viral infections
White Matter Pathology
There is an inflammatory response of myelin in the CNS. This may be due to a problem with the blood brain barrier that accounts for lesions.
Gray Matter Pathology
Less is known about exact pathological processes occurring in GM damage
Some lesions extend from the pia through the first 3 layers of cell bodies in the cortex
Evidence shows that axonal damage can occur. If the cell body dies, the axon will degenerate
Could also be due to a retrograde signal that leads to damage of the cell body
What contributes to the severity of symptoms
the degree of swelling following breakdown of myelin
Why may gray matter involvement increase as the disease progresses?
This is because re-myelinzation becomes less effective
What do the specific symptoms of MS depend on?
Depend on WHERE myelin and gray matter is attacked
Where is white matter damage more common?
More common white matter damage is in the optic nerve, cerebellum, SC, brainstem then cerebral cortex
How quickly can symptoms develop in MS?
Can develop over hours or several days or even weeks
Most commonly 6-15 hours
Some symptoms are more continuous such as fatigue and depression
List the most common symptoms of MS
• FATIGUE • DEPRESSION • Focal muscle weakness • Ocular disturbance o Nystagmus (cerebellar lesion) o Double/blurry vision • Urinary and bowel disturbance • Gait ataxia (cerebellar lesion) • Spasticity/babinski (UMN lesion) • Parasthesias/anesthesias (somatosensory path lesion) • Dysmetria/intention tremor/ataxia (cerebellar lesion) • Neuropathic pain • Heat intolerance
Less common, but not uncommon symptoms
- Dysarthria
- Scanning speech
- Facial palsy (UMN lesion)
- Vertigo
- Cognitive dysfunction
- Short-term memory
- Conceptual reasoning
- Problem solving and multi-tasking issues
Rarer symptoms
- Decreased hearing
- Dysphagia
- Seizure
- Tinnitus
what causes ocular disturabances
CN II is myelinated by oligodendrocytes resulting in vulnerability to MS whereas all other CN are myelinated by Schwann cells
What are paraclinical signs?
pertaining to abnormalities (e.g., morphological or biochemical) underlying clinical manifestations (e.g., chest pain or fever).
the 3 paraclinical signs associated with MS
UWOs
VEP
Lumbar Puncture
What are UWOs
unidentified white objects found on the MRI
o One can have totally benign spots
o May have symptoms before any white spots develop
o Very specific criteria for white spots
What are VEPs
visual evoked potentials
o Slowed conduction of optic nerve
o Also have somatosensory evoked potentials (SSEP) and brainstem auditory evoked potentials (BAEP)
Reason for lumbar puncture
o See what’s floating in the CSF
o “myelin basic proteins” are present during an acute attack
This is a reason to give corticosteroids
what are the 2 ways to diagnose definitive MS
- 2 attacks more than 30 days apart with clinical evidence of 2 separate lesions
- 2 attacks with clinical evidence of 1 lesion and paraclinical evidence of separate lesion (abnormal MRI, abnormal evoked potentials or abnormal CSF)
What is clinical isolated syndrome?
an initial neurological episode or attack that lasts at least 24 hours and can be monofocal or multifocal
• One “event” that may “look” like an MS event
• Some with CIS will switch to MS
What do those who convert to MS show?
They tend to show GM involvement
Having what on the MRI makes people wtih CIS 63% more likely to be diagnosed with MS
having white spots on the MRI makes them more likely to end up being diagnosed with MS
Describe Benign MS
relapsing remitting but NO progressions has relapse but goes back to baseline fully functional 15 years after diagnosis little to no disability 20-25%
describe relapsing-remitting
most common
clearly defined exacerbation and remissions that can last from days to months
residual deficits but can have recovery from exacerbations
describe progressive relapsing
least common
exacerbations and remissions
continued disease progression between exacerbations
describe Secondary progressive
o Occurs in 90% of those with relapsing-remitting(RR)
o Starts at RR then suddenly becomes primary progressive
o Geometric worsening of baseline at any point; usually have warning signs
o 14 fold increase in GM involvement
o Most common we will see at PTs
describe primary progressive
o Sometimes called unrelenting MS
o 10-15%
o Do not respond to conventional treatments
o Worse case
o Have a problem with oligodendrocytes and perhaps significant GM involvement
o Tend to be older when diagnosed
Factors that contribute to a favorable diagnosis
- Low relapse rate
- Long interval between first and second relapse
- Complete recovery from first relapse
- Younger age at onset
- Female
- Low disability and 2 years and 5 years post diagnosis
factors that contribute to an unfavorable diagnosis
- High exacerbation rate in first 5 years, short time between 2st and 2nd attack
- Cerebellar, sphincter or cognitive symptoms early
- > age than 40 at onset
- Lower brainstem involvement (CN IX, X, XII)
factors that contribute to patients psychological status relating to MS
• Difficulty getting diagnosed o Often misdiagnosed initially o “somatoform conversion disorder” Converting psychological to physical • Unpredictable course • Covert symptoms o Fatigue, depression, bladder, vision
the 2 broad goals of treatment
control relapses and symptom managment
List ways to control relapses
anti-inflammatory corticosteroids
decrease frequency of exacerbations with immune modulators
immunosuppressants
what is the top choice for coriticosteriods to control relapses
IV prednisone
For which clinical course are immunosuppressants used
used in “unrelenting” MS
blocks Tcell attack in the brain
What symptoms do we try to manage?
depression fatigue/lassitude heat intolerance stiffness/spasticity bladder dysfunction bowel dysfunction pain mobility tremors emotional lability seizures
How do we determine appropriate dosage for Baclofen?
- Way to find the right dose is gradually increase
2. It is too much when you get marked weakness “dishrag feeling”
What can happen with sudden stoppage of Baclofen
seizures and hallucinatons
What is the primary drug for stiffness/spasticity
Baclofen
“artificial GABA”
Why is Bacolfen a great drug?
minimal side effects (weakness, letarghy, GI issues) that don’t last long because they have a short 1/2 life so they go away quickly
What does the dosing start at for Baclofen?
starts at 5 mg/ day, 3x a day
What is the depression rate for MS
60%
medications such as tricyclics are used
define lassitude
“hit the wall” feeling
different from muscle fatigue
what makes up primary fatigue
both motor fatigue and lassitude
it is the most encompassing symptom
what is secondary fatigue
the body’s response to the disease
a result of MS symptoms and trying to compensate for them
What does Amprya do?
used for motor fatigue and can increase conduction of AP
What does Provigil?
an anti-narcoleptic that is effective for lassitude
