B2W3 Trans Phys Multiple Sclerosis Flashcards
Multiple Sclerosis
Inflammatory neurodegenerative disease of the central nervous system.
Unknown cause but there appears to be risk factors and genetic predispositions
Target of MS autoimmune response
Oligodendrocytes
Three Main Glial Cells
Oligodendrocytes, Astrocytes, and Microglia
Oligodendrocytes
Provide insulation and support to neurons of the CNS through the creation of myelin.
One oligodendrocyte can bind to upwards of 50 axons
Astrocytes
Biochemical support of endothelial cells. Maintains the BBB provides nutrients and repairs damage.
Microglia
Macrophages of the brain and spinal cord. Get rid of damaged neurons and infectious agents
Onset of MS
Ages 20-50
2-3x more common in women
Stages of MS
RIS (Radiologically Isolated Syndrome), Preclinical, CIS (Clinical Isolated Syndrome), Relapsing and Remitting, and Secondary Progressive
RIS Radiologically Isolated Syndrome
Signs of MS in scans but no physical symptoms present
CIS Clinical Isolated Syndrome
First appearance of MS symptoms
End of Preclinical phase
Relapsing-Remitting
Cycle of periods of high MS disability and periods of low MS disability but with a general trend towards higher disability. Highest point of inflammation
Secondary Progressive
No more relapses in disability. Overall result in a decrease in brain volume and axon loss
Risk Factors of MS
Epstein-Barr Virus (Mono), Smoking, Low Vitamin D, Obesity, and genetic mutations of the human leukocyte antigen
Immunology of MS
Regulatory T cells maintain a balance of inflammatory and anti-inflammatory factors. In MS Regulatory T cells malfunction and upregulate pro-inflammatory factors TH1/TH17.
Inflammation disrupts the BBB and allows for the entrance and maturation of B Cells in the CNS
B Cells in MS
B Cells are antigens to T cells triggering the immune response of T Cells, produce antibodies that activate macrophages and NK cells, can form aggregates in the meninges, and produces proinflammatory cytokines
B cells are not usually found within the CSF but are in MS patients
Pathologic Hallmark of MS
Alterations of the BBB, inflammation, demyelination, axonal degeneration, neuronal loss, and gliosis
Active MS Lesions
Macrophages contain myelin debris and lymphocytes infiltrate through gaps in the BBB
Gliosis
Over production of large glial cells
Relapse-Remitting Multiple Sclerosis
80-85% of patients have MS which has periods of high and low disability followed by a secondary progressive phase where disability continues to increase
Primary Progressive Multiple Sclerosis
10-15% of patients have a continual worsening of MS symptoms and disability without periods of remitting
Role of Gray and White Matter
MS is both a disease of the white and gray matter, and gray matter (demyelinating)
lesions are known to occur early in the disease
Inflammation, demyelination and neurodegeneration, typical of white matter
involvement in MS, are seen also in the gray matter
Gray matter atrophy is a major component of MS pathobiology and correlates with
clinical disability better than damage to the white matter
MS Relapse
Patient reported or observed symptoms that last 24 hours or more
Two Diagnostic Criteria for MS
Dissemination in Space
Dissemination in Time
Dissemination in Space
Signs of MS in different and unrelated places as shown on an MRI
