MS, MG, MD

Question 1

Both d/t weakness; can both be considered disorders of nerve conduction; autoimmune, lymphocytes

Answer 1

MS & MG

Question 2

Wrap around the axon of a neuron, insulating it, and forming the myelin sheath

Answer 2

Schwann cells

Question 3

Similar function as Schwann cells, insulating neuronal axons and forming a myelin sheath; only found in the CNS while Schwann cells are only in PNS

Answer 3

Oligodendrocytes

Question 4

Supporting cell found in the CNS; form a spider like network and facilitate nutrient extraction from the blood supply and disposal of cellular waste products

Answer 4

Astrocytes

Question 5

Exclusive to CNS, circulate through the nervous system helping with immunity by destroying bacteria or dead cells

Answer 5

Microglial cells

Question 6

Line areas of the NS that have CSF and thees cells help circulate the fluid

Answer 6

Ependymal cells

Question 7

Autoimmune disease? which causes inflammatory demyelination of CNS (no specific antibody found); Demyelination of axons reducers neurons ability to function

Answer 7

Multiple sclerosis

Question 8

Inflammation-> demyelination-> axonal degeneration

Answer 8

Multiple sclerosis

Question 9

Shows response to tx w/ immunomodulating rx

Answer 9

Multiple sclerosis

Question 10

Disruption of BBB; Rx that block T cell movement into CSF improve the sx/s of this

Answer 10

Multiple sclerosis

Question 11

Sx/s= weakness, fatigue, numbness, tingling, unsteadiness in a limb, spastic paraparesis; retrobulbar neuritis/ optic neuritis (blurred/dimmed vision, blind spots, pain w/ eye movement, HA, sudden color blindness, impaired night vision, impaired contrast sensitivity, diplopia); disequilibrium/vertigo, pain, sphincter disturbance

Answer 11

Multiple Sclerosis (sxs very vague!)

Question 12

Relapses and remissions; onset between 15-50; optic neuritis; Lhermitte’s sign (person flexes neck and get a shock like pain down their spine); Internuclear ophthalmoplegia; fatigue, Uhthoff’s phenomenon (symptoms worsened in HOT environments)

Answer 12

Multiple sclerosis

Question 13

Dx: must show 2 or more DIFFERENT areas in central areas of white matter affected at DIFFERENT times

Answer 13

Multiple sclerosis

Question 14

Test of choice to dx clinically suspected MS=

Answer 14

MRI

Question 15

Lesion is the cerebral or spinal plaque-discrete region of demyelination with initially preserved axon; found in the periventricular, juxtacortical, infratentorial and/or spinal cord

Answer 15

Multiple sclerosis

Question 16

Dx: increased Gadolinium enhancement may indicate acute lesion (often asymptomatic)

Answer 16

Multiple sclerosis

Question 17

Lumbar puncture may have mild lymphocytosis, may have IgG in CSF; albumin in CSF indicated disruption of BBB; Presence of oligoclonal bands (series of distinct bands found in the immunoglobulin of the CSF) is highly suggestive

Answer 17

Multiple sclerosis

Question 18

Type of MS; an initial episode then months/years before new systems emerge or previous symptoms return; cycle can lead to incomplete remissions and progressive disability with weakness, spasticity, ataxia of limbs, impaired vision and urinary incontinence; physical findings= optic atrophy, nystagmus, dysarthria, pyramidal/sensory/cerebellar deficits in one or multiple limbs; Uhthoff’s phenomenon!

Answer 18

Relapsing-remitting MS (RRMS)

Question 19

NO CURE; tx aimed at improving quality of life and limiting disability; acute attached tx with glucocorticoids (methylprednisolone)

Answer 19

Multiple sclerosis

Question 20

First drugs that were available for MS; cytokine that modulates immune responsiveness

Answer 20

Interferons

Question 21

Disease modifying therapy for MS, CIS=

Answer 21

injection therapy w/ interferon beta or glatiramer

Question 22

Disease modifying therapy for RRMS-“convenience” approach=

Answer 22

oral therapy with dimethyl fumarate or teriflunomide

Question 23

Disease modifying therapy for RRMS-“efficacy” approach=

Answer 23

infusion therapy with natalizumab

Question 24

Problem at the synapse, rather than the myelin sheath:

Answer 24

Myasthenia gravis

Question 25

autoimmune disease; uncommon; MC disease of neuromuscular transmission; Ab against nicotinic AchR at NMJ; some Ab impair ability of Ach to bind to AchR, other Ab destroy AchR

Answer 25

Myasthenia gravis

Question 26

Also, Ab against MuSK (muscarinic tyrosine kinase); MuSK proteins mediate clustering of AchR during NMJ formation and associated with AchR maintenance; Ocular and generalized manifestations

Answer 26

Myasthenia gravis

Question 27

Up to 75% of pts have thyme abnormalities

Answer 27

Myasthenia Gravis

Question 28

Organ located in the upper anterior portion of the chest cavity just behind the sternum; main function is to roved an area for T lymphocyte maturation; vital in protecting against autoimmunity

Answer 28

Thymus

Question 29

Commonly associated with facial symptoms, ptosis, diplopia, bulbar muscle weakness, expressionless face, neck muscles; May progress DOWN to respiratory muscles, limb weakness

Answer 29

Myasthenia Gravis

Question 30

Fatiguability of muscles; may have frank ptosis on exam, slack jaw; The simpson test; Cogan lid twitch sign

Answer 30

Myasthenia Gravis

Question 31

Short-acting AchE inhibitor; c/i in pts with cardiac disease or asthma; may proceed increased salivation or adnominal cramping, symptomatic bradycardia or bronchospasm

Answer 31

Tensilon test

Question 32

Have circulating Ab against nicotinic AchR

Answer 32

Myasthenia gravis

Question 33

Most pts with Seropositive, have timid abnormalities, especially AchR-Ab

Answer 33

Myasthenia gravis

Question 34

Includes electrophysiologic testing: repetitive nerve stimulation studies; single fiber EMG

Answer 34

Myasthenia gravis

Question 35

Respiratory weakness may lead to respiratory failure; can occur spontaneously during active phase of disease or be precipitated by surgery, infection, medications or tapering of immunosuppression;

Answer 35

Myasthenia gravis: CRISIS

Question 36

Inherited disorders causing progressive muscle weakness and atrophy d/t a genetic defect; common theme of muscle weakness; some forms cause cardiac dysfunction and cognitive deficits

Answer 36

Muscular dystrophies

Question 37

Defective gene on X chromosome responsible for producing dystrophin (a protein that protects muscles); a dystrophin deficit leads to enzymatic muscle breakdown; occurs in males; Sx/s start centrally (trunk) and spread to legs first; elevations in CK

Answer 37

Duchenne muscular dystrophy (DMD)

Question 38

Those affected make SOME dystrophin; defective gene on X chromosome responsible for producing dystrophin; occurs in males

Answer 38

Becker muscular dystrophy

Question 39

Can occur in M/F; muscle weakness usually begins in arms in teen years, then progresses to legs and face; CLASSIC TRIAD (contractors of elbows, ankle plantar flexors and spine early; later onset of humeroperoneal weakness, & cardiac abnormalities)

Answer 39

Emery-Dreifuss Muscular dystrophy

Question 40

MC form of MD (in whites); M/F; 2 genetic subtypes; muscle stiffness, inability to relax muscles after contraction; affects different body systems causing muscle loss and weakness-facial muscles, arms, legs, also cardiac complications, cataracts, abnormal intellectual functioning, excessive daytime somnolence

Answer 40

Myotonic dystrophy

Question 41

Multiple subtypes (>20); affects shoulder girdle and/or hip girdle; tx focused on stretching to prevent contractures

Answer 41

Limb-girdle MD