L21 Multiple Sclerosis Flashcards
What is one factor that contributes to the prevalence of multiple sclerosis?
As you move farther from the equator, the prevalence goes up, and this may be due to the vitamin D deficiency hypothesis.
Not enough vitamin D leads to increased rates of MS, in the world and also in countries
What are four different effects in the neurons that accompanies MS?
Demyelination, axonal loss, axonal degeneration, inflammation
What does the age distribution of MS look like?
Hits the younger generation more, peaks at around 25-30.
Different from other neurodegenerative diseases (15-45)
Low prevalence around 10 and 60
What is the prevalence of pediatric MS?
6% of MS in total is pediatric, 3-10% of MS patients see an onset at 18 yrs old or younger
Age of onset affects disease progression
Is there a gender difference in the prevalence of MS?
YES
Female to male ratio is 3:1, but males have a later onset and more progressive disease
What are the three categories of MS?
Primary progressing: 10% of people, slow and continuous progression of the disease
Secondary progressing: happens after R and R type (80% of people)
Relapse/remitting (usually turns into SP): flare, recover, flare, recover, and recover less every time
What scale is used to score MS patients on their degree of disability?
Expanded Disability Status Scale (EDSS), used for motor disability
From 0-10, 10 being the highest level of disability, different milestones are used such as requiring assistance to walk (6), restricted to a wheelchair (7), restricted to bed/chair (8), confined to bed (9), and death is 10
What is the pathology of MS?
Demyelination of axons, many lesions in different parts of the brain (usually localized)
What are the pathway for treatment in MS?
MS involved demyelination of axons, and to repair this you can either remyelinate the neurons.
What is the pathology of an MS plaque?
Decreased axonal density in the lesion
What are potential causes of MS?
Genes
Smoking
Infections (not necessarily a cause, associated with EBV (mono), but 78% of the population has had this and they do not all have MS)
Salt can increase inflammation and activation of the immune system, thus increasing MS
Vitamin D deficiency
What do genes contribute to MS?
It is not genetically transmitted, it is associated with DRB gene but it is not causal, simple a predisposition
What is EAE and what it is immune pathology?
EAE is a demyelinating disease that can be transferred between mice via transfer of lymphocytes from sick mouse to healthy mouse.
First you get naive MBP recognizing T-cells that are activated by MBP on antigen presenting cells. They are then differentiated into Th1, Th2, Th17 and T regulatory cells (all release cytokines and initiate inflammation), which cross the blood brain barrier into the CNS, along with B cells that further activate T-cells and these lead to chronic inflammation, demyelination and axonal damage
What are 8 things that happen and contribute to the pathogenesis of MS?
Astrocyte activation, neuro-axonal degeneration, excitotoxicity, microglia activation, energy failure, inflammation, ionic imbalance and increased sodium balance, demyelination
What type of brain atrophy do you see in Ms?
Loss of white matter AND grey matter, get big ventricles filled with fluid
