6.2.3 Myelin Disorders Flashcards
What are the main presentation features of central pontine myelitis?
Rapid quadriplegia, basis pontis lesion
What are the two main subtypes of myelin disorders?
Demyelinating disease and leukodystrophies
What are some of the unique features of acute hemorrhagic encephalomyelitis (Weston Hurst)?
Acquired chronic inflammatory disorder of CNS with distinct episodes of neurological deficits, separated in time, attributable to white matter lesions that are separated in space
Multiple sclerosis
What are the diagnostic criteria (main features) of NMO?
Optic Neuritis + Myelitis + NMO-IgG seropositivity
Name this condition
Acute hemorrhagic encephalomyelitis
What are some of the unique features of acute disseminated encephalomyelitis (ADEM)?
What gene is commonly associated with MS in most populations?
HLA-DR15 (a split of DR2)
Does not follow Mendelian genetics
Cytokine-receptor genes have been linked to MS susceptibility (IL2RA, IL7RA)
Which cranial nerve is commonly affected by MS and why?
Optic nerve (and chiasm) because the nerve is covered in meninges and still has central myelination
Name this condition and its characteristic cell that is being encircled
Neuromyelitis optica; Creutzfeldt cell
What are the key features of Krabbe’s?
Lysosomal Disease
Globoid cells
What virus is associated progressive multifocal leukoencephalopahty (PML)? What causes someone infected with this virus to progress to PML?
JC Virus; Becoming immunocompromised
What are leukodystrophies?
Progressive inherited diseases with abnormal synthesis or turnover of myelin; most are AR in inheritance
What are some of the unique characteristics of Acute MS?
Childhood to young adults, rapid progression, relatively unresponsive to steriods
What is the pathogenesis of MS?
What is being shown in this image?
Inactive MS plaque (no blue due to destruction of myelin, few macrophages surrounding the blood vessels)
Where is demyelination confined to in MS?
CNS
What is the autoimmune target of neuromyelitis optica (NMO) that distinguishes it from MS?
NMO-Ab towards aquaporin-4
What is the typical symptomalogy of PML? What is the typical course and end result?
Progressive visual, motor, dementia, and sensory symptoms
Short course (6-12 months) leading to death
Who typically presents with adrenoleukodystrophy? Why?
Young boys; x-linked
Name this condition
Adrenoleukodystrophy; black lines pointing at gemistocytic astrocytes
Parieto-occipital white matter preferentially affected
Perivascular CD8 T-lymphocytes
Macrophages, adrenal cortical cells, Schwann, Leydig cells: trilaminar lipid inclusions
What is the inheritance of alexander’s dz?
AD due to de novo/mutation in GFAP gene
What is shown in the center of this histological image?
Active MS plaque
Neurofilament: indicates the preservation of axons
Macrophages: presence indicates active destruction (active)
What is the difference between an active and inactive plaque of MS?
Active plaque: Pink and swollen with presence of macrophages
Inactive plaque: inflammation and macrophages have cleared out, lack of myelin
Name this condition
Alexander’s disease (more rosenthal fibers than any other disease)
What are the key features of Metachromtic LD?
Metachromatic material
Fill in the classification and key pathologic features of these leukodystrophies
How will Alexander’s disease present in young children?
Seizures, spasticity, megalencephaly, developmental delay
What are the key features of Adreno-LD?
Perivascular inflammation
Peroxisomal
What is the most common form of MS?
Charcot, chronic relapsing and remitting
What are the three arrows pointing at?
Orange: Schwann cell
Blue: corpora amylacea body
Red: oligodendrocytes
What are some potential causes of central pontine myelitis?
Alcoholism, liver transplant, electrolyte imbalances
Rapid sodium correction association
What gene is associated with adrenoleukodystrophy?
ABCD1 Transporter gene (Xq28)
What is being shown in this histo slide?
Transition from central to peripheral myelin
What category of diseases: Myelin damage with relative preservation of axons?
Demyelinating disease
What is elevated in the CSF of MS?
mild elevation in protein (oligoclonal bands), lymphoctes
