NEUROLOGY: 12. MULTIPLE SCLEROSIS EXAM
QUESTIONS AND ANSWERS
Epidemiology
Autoimmune DZ
Peak between ages of 20-30; higher incidence women
Disease increases in frequency in latitude
High prevalence N. Europe, N. US, S Canada, S Australia, and New Zealand
Caucasian populations greater risk
Etiology
Cause of MS is unknown/multifactorial:
-Genetic susceptibility
-Autoimmune mechanisms
-Environment
Genetic susceptibility
Lifetime risk in general population small
15% of pts with MS have an affected relative
25% concordance rate in monozygotic twins
Multiple genes likely confer susceptibility
Immunology
Activity of suppressor CD8+ T cells is REDUCED
Increased ratio of Inducer T cells (pro-inflammatory)
Amount of IgG in CSF is increased
-only a few clones are activated
-Oligoclonal
Environment
Triggers
Sunlight/Vitamin D: Decreased = higher risk; inverse relationship w/ cancer regarding sunlight
, Hygiene hypothesis: immune stimulation while young is good
Viruses: HSV 6, Epstein bar virus, others
Early or acute lesions
Marked hypercellularity, macrophage infiltration, astrocyotiss
Peri-venous inflammation with lymphocytes and plasma cells
Peri-venous inflammation with lymphocytes and plasma cells
BW for Multiple Sclerosis pathology
Inactive lesions
Hypocellular
Scars over time
Major Symptom themes
Dissemination in TIME and SPACE: >1 lesion in >1 part over time
Exacerbations and remission: w/ subsequent attacks, remissions may be incomplete or not occur
Clinical manifestations may be transient or difficult to describe or verify objectively
Motor symptoms
Limb weakness is most common motor sign
Spasticity: augments the gait disturbance
UMN signs (hyperreflexia, Babinski)
Sensory symptoms
Positive or negative symptoms
Impairment of vibratory or position sense, pain, temp, or touch
Lhermitte sign: "Electric" sense down back after flexion of neck. Indicate posterior column
lesion
Lhermitte sign
Sensation of "electricity" down the back after flexion of the neck
Indicates a lesion of posterior column of cervical cord
QUESTIONS AND ANSWERS
Epidemiology
Autoimmune DZ
Peak between ages of 20-30; higher incidence women
Disease increases in frequency in latitude
High prevalence N. Europe, N. US, S Canada, S Australia, and New Zealand
Caucasian populations greater risk
Etiology
Cause of MS is unknown/multifactorial:
-Genetic susceptibility
-Autoimmune mechanisms
-Environment
Genetic susceptibility
Lifetime risk in general population small
15% of pts with MS have an affected relative
25% concordance rate in monozygotic twins
Multiple genes likely confer susceptibility
Immunology
Activity of suppressor CD8+ T cells is REDUCED
Increased ratio of Inducer T cells (pro-inflammatory)
Amount of IgG in CSF is increased
-only a few clones are activated
-Oligoclonal
Environment
Triggers
Sunlight/Vitamin D: Decreased = higher risk; inverse relationship w/ cancer regarding sunlight
, Hygiene hypothesis: immune stimulation while young is good
Viruses: HSV 6, Epstein bar virus, others
Early or acute lesions
Marked hypercellularity, macrophage infiltration, astrocyotiss
Peri-venous inflammation with lymphocytes and plasma cells
Peri-venous inflammation with lymphocytes and plasma cells
BW for Multiple Sclerosis pathology
Inactive lesions
Hypocellular
Scars over time
Major Symptom themes
Dissemination in TIME and SPACE: >1 lesion in >1 part over time
Exacerbations and remission: w/ subsequent attacks, remissions may be incomplete or not occur
Clinical manifestations may be transient or difficult to describe or verify objectively
Motor symptoms
Limb weakness is most common motor sign
Spasticity: augments the gait disturbance
UMN signs (hyperreflexia, Babinski)
Sensory symptoms
Positive or negative symptoms
Impairment of vibratory or position sense, pain, temp, or touch
Lhermitte sign: "Electric" sense down back after flexion of neck. Indicate posterior column
lesion
Lhermitte sign
Sensation of "electricity" down the back after flexion of the neck
Indicates a lesion of posterior column of cervical cord
