Multiple Sclerosis Flashcards
What is MS?
Autoimmune disorder that leads to destruction of protective myelin sheath that surrounds axons in the CNS which results in conduction problems. Symptoms of MS can vary depending on the location of CNS damage.
Who is at higher risk of getting MS?
White people who live far away from the equator. Low vit D, EBV and smoking are associated with the diagnosis of MS.
What cell type makes up the myelin sheath?
Oligodendrocytes
Explain what is happening immunologically in MS
The immune system fails to recognize the CNS as “self” at considers it foreign. Activated T cells produce matrix metalloproteinases (enzymes that destroy the extracellular matrix) which allows T cells to enter the BBB and produce inflammatory cytokines which destroys the myelin sheath.
What criteria has been established to air clinicians in the diagnosis process?
Mcdonald criteria
What disorders may look like MS?
MS is a diagnosis of exclusion and CNS infections, CNS inflammatory conditions, Vit B12 deficiency, brain/spinal cord damage, genetic disorders and CNS microvascular conditions may look like MS and must be ruled out before making a diagnosis.
Explain the 5 “classes” of symptoms that correlate to MS
Sensory: Loss of sensation, bizarre sensations
Visual: Eye pain, vision impairment, loss of light perception
Motor: impaired coordination, weakness, paralysis, tremors, spasticity
Organ: Urinary frequency/retention, incontinence, constipation, change in sexual function
Systemic/CNS: Fatigue, depression, heat sensitivity, cognitive changes
An attack must be confirmed with a lesion on the CNS using what?
MRI must show lesions that show up in separate space and time.
What are the 4 categories of MS and which one is the most common?
Relapsing remitting (85%), secondary progressive (15%), primary progressive (15%), progressing relapsing (very rare).
3 goals of therapy with MS medications
Minimize attacks, CNS damage, and disability.
What are the brand names of the interferon BETA 1a? How frequently and by what route are they administered?
Avonex IM Q week, Rebif SQ TIW and Plegridy SQ Q 2 weeks
What is the mechanism of action for interferon therapy?
They modulate the immune system by reducing activity of T cells and MHCs. They also reduce matrix metalloproteinases that break down the BBB.
Adverse effects, warnings and contraindications with interferon therapy?
Side effects: Flu-like symptoms, muscle pain, nausea, HA, UTI and depression, injection site reactions.
Warnings: Risk of suicide, anemia, and possibly seizures..
Contraindications: Hypersensitivity.
What is fingolimod mechanism? Side effects? Contraindications? and warnings?
Fingolimod is a S1P receptor modulator that regulates inflammatory processes that defines the immune system. This in turn inhibits circulating T and B cells and prevents autoimmune destruction.
Inhibits CYP4F2.
Side effects: HA, diarrhea, increase LFT, cough, back pain, influenza and herpes.
Warnings: Bradycardia, AV blocks, infections, macular edema.
Contraindicated: History of cardiological issues.
Mech of action, side effects, warnings and contraindications of teriflunamide?
Mech: Dihydroorotate dehydrogenase inhibitor. Interferes with DNA production which reduces T cell proliferation.
Shouldn’t be used with leflunomide.
Side effects: HA, fatigue, N/D, influenza and UTI.
Warnings: Hepatic injury, infections, acute renal failure, hyperkalemia, increased BP and uric acid.
Contraindicated in hepatic disease and pregnancy and leflunomide.