Multiple Sclerosis Flashcards
What is Multiple Sclerosis?
is an immune mediated DEmyelination disease of the central nervous system.
What is affected in MS?
myelin sheath (which is a protective membrane that wraps around the axon of a nerve cell) is destroyed with inflammation
- therefore, OLIGODENDROCYTES which are making myelin are affected too
When does MS occur?
when activated immune cells INFILTRATE the CNS and ATTACK myelin.
- suggests MS is not a single disease but rather a SPECTRUM (immune mediated disease)
What is the Epidemiology of MS?
- Canada’s disease (highest prevalence)
- majority b/t 15-40 yoa
What is a reason why MS is called a spectrum disease?
b/c see a spectrum of symptoms b/c MS can happen ANYWHERE in CNS
- like brain, visual area etc.
- therefore, we see a spectrum of symptoms
What are the main symptoms?
- Fatigue
- Numbness, tingling
- Walking difficulty
- Pain
- Muscle spasms
What are the identifies predisposing factors (triggers) of MS?
GENETIC: 200 genes have been associated
- identical twins show 30% chance
- siblings show 2-5% chance
- FEMALES>males (but males seem to have worse symptoms)
- Viruses (EBV*, VZV)
- Pollutants
- VITAMIN D DEFICIENCY!
- Smoking
- Excessive salt intake
regardless, causes immune mediated attack
How do you diagnose for MS?
- BLOOD TESTS
- SPINAL TAP (lumbar puncture) - to check abnormalities in antibodies
- NEUROLOGICAL & EVOKED POTENTIAL TESTS
- MRI - check for lesions in brain/SC (MS inflammatory lesions around BV’s & demyelinated MS plaques)
What are the clinical classification of MS?
- Progressive Relapsing (PRMS)
- Secondary Progressive (SPMS)
- Primary Progressive (PPMS)
- Relapsing Remitting (RRMS)
Progressive Relapsing (PRMS):
Steady progression since onset with super-imposed attacks.
Secondary progressive (SPMS):
Initial RRMS that suddenly begins to decline without periods of remission and relapses.
(like RRMS, but overtime the immune attack becomes constant which causes a steady progression of disability)
Primary Progressive (PPMS)
Gradual progression of the disease from its onset with no relapses or remissions
(constant attack, but with bouts superimposed, which means this disability happens even faster)
Relapsing Remitting (RRMS):
Unpredictable attacks which may or may not leave permanent deficits followed by periods of remission (the MOST COMMON)
What does MS involve?
BOTH innate & adaptive immune response peripherally & in the CNS
Immune response in the pathogenesis of MS
MS pathogenesis starts from periphery:
- Antigen presentation & T-cell activation
- B-cell activation & antibody formation
- Chemotaxins, adhesion & migration
- Macrophage activation & demyelination
- Axonal degredation & loss of trophic support
- Apoptosis