Demyelinating Diseases

Question 1

Components of Myelin

Answer 1

Lipids

Proteins

Question 2

What makes up the White Mater of the brain?

Answer 2

Axons
Myelin
Oligodendrocytes
Astrocytes
Microglia
Blood Vessels

Question 3

Disease of myelin formation or maintenance by INTRINSIC (genetic) cause

Answer 3

Leukodystrophy

Question 4

Diseaes of NORMALLY formed myelin caused by EXTRINSIC (injury/autoimmune) cause; axons typically well PRESERVED

Answer 4

Demyelinating Disease

Question 5

Demyelinating Disease; myelin degeneration with preservation of axons; perivascular chronic inflammatory cells, LOSS of oligodendrocytes

Answer 5

Multiple Sclerosis

Question 6

Diagnostic tests for MS

Answer 6

Hx (“multiple” episodes)
MRI (acute lesions enhance with contrast)
Lumbar Puncture (detection of oligoclonal IgG bands)

Question 7

3/4 of patients with MS are (male/female)

Answer 7

Female

Question 8

Typical symptoms of MS

Answer 8

Monocular Visual Loss
Double vision
Ataxia (clumsiness)
Limb Weakness

Question 9

Treatment for MS

Answer 9

Acute episodes: IV steroids

Disease Modifying Agents

Question 10

PEDIATRIC, immune-mediated disease; demyelination after a preceding viral infection (Measles, Varicella and Rubella) or recent immunization; asymmetric foci in white matter on MRI

Answer 10

Acute Disseminated Encephalomyelitis (ADEM)

Question 11

Demyelination Disease; caused by Papova virus (JC virus strain) in Immuno-compromised patients; RAPID progression; multiple foci in SUBCORTICAL white matter; owl-eye cells can be seen histologically

Answer 11

Progressive Multifocal Leukoencephalopathy (PML)

Question 12

Diffuse pallor of Cerebral white matter; perivascular presence of multinucleated giant cells

Answer 12

AIDS Leukoencephalopathy

Question 13

Demyelination Disease; due to rapid correction of serum electrolytes, resulting in rapid/excessive rise in serium sodium; demyelination occurs in the center of Pons

Answer 13

Central Pontine Myelinolysis (Osmotic Myelinolysis)

Question 14

What are the differences of the various Leukodystrophies (Disease of myelin formation or maintenance by GENETIC cause) in regards to macrophage contents?

Answer 14

ALD: LCFAs
MLD: sulfatides
GLD: galactocerebroside

Question 15

The various Leukodystrophies usually have the preservation of the __________ in the remaining white matter

Answer 15

U-fibers

Question 16

X-linked Leukodystrophy; elevated very Long Chain Fatty Acids in macrophages

Answer 16

ALD (demyelination predominantly in Occipital)

OR

AMN (demyelination predominantly in Brainstem and Spinal cord)

Question 17

Autosomal recessive Leukodystrophy; member of the lysosomal storage diseases (specifically sphingolipidoses); Arylsulfatase A deficiency, resulting in cerebroside sulfate accumulation & destruction of myelin; cause dementia and ataxia

Answer 17

Metachromatic Leukodystrophy (MLD)

Question 18

Autosomal recessive Leukodystrophy; member of the lysosomal storage diseases (specifically sphingolipidoses); Galactocerebrosidase deficiency, causing Galactocerebroside accumulation & myelin destruction; cause developmental delay, peripheral neuropathy, and optic atrophy

Answer 18

Krabbe Disease (aka. GLD)