Pathology of Demyelinating Disease Flashcards
Multiple Sclerosis
Pathogenesis:
Genetic component:
Morphology:
Histology:
Multiple Sclerosis is an autoimmune demyelinating disorder characterized by distinct episodes of neurologic deficits, separated in time, attributable to white matter lesions that are separated in space.
Pathogenesis: lesions are secondary to an autoimmune response directed against components of the myelin sheath (T-Lymphocyte initiated response)
Genetic component: DR2
Morphology: White Matter disease
What is this?
age at presentation:
histology:
Multiple Sclerosis Lesion
age at presentation: usually presents in early adulthood but can be any age. 2X F>M
histology:
active plaques- ongoing breakdown w/ abudnant lymphocytes
inactive plaque- no active breakdown, no inflammatory cells, no myelination of axons, decreased oligodendrocytes but increased astrocytes and gliosis
Multiple Sclerosis
- Clinical Features:
- CSF examination
- what type of imaging can be used to assess disease progression?
Multiple Sclerosis
- Clinical Features: b/c a lesion can occur anywhere in the CNS, clinical lesions can occur anywhere- however some symptoms occur routinely
- Unilateral vision impairment
- ataxia, nystagmus, and cranial nerve signs (brainstem involvement)
- CSF examination:
- Mildly elevated protein and pleocytosis (increased lymphocytes)
- increased IgG levels and oligoclonal IgG bands on immunoelectrophoresis
- An MRI can be used to assess disease progression?
Neuromyelitis Optica
- definition:
- characteristics:
Neuromyelitis Optica
- definition: synchronous bilateral optic neuritis and spinal cord demyelination
- synchronus bilateral blurry vision and weakness or paralysis in the legs or arms, loss of sensation, and problems with bladder/bowel function
- characteristics:
- women>men
- less recovery than MS from initial attack
Neuromyelitis Optica
- Antibodies against ________
- what is the MOA for these antibodies?
- CSF examination:
Neuromyelitis Optica
- Antibodies against aquaporin-4
- these antibodies injure astrocytes through complement-dependent mechanisms.
- CSF examination: often see neutrophils
Neuromyelitis Optica
- Histology:
- Therapy:
Neuromyelitis Optica
- Histology: within damaged areas of white matter:
- necrosis, inflammatory cells
- vascular deposition of immunoglobulin and complement
- Therapy: reduction of Ab burden through:
- plasmaphersis
- depletion of B-cells via anti- CD20
Acute Disseminated Encephalomyelitis
- acute monophasic demyelinating disease that follows a _________.
- How long does it take to develop?
- what are the symptoms?
- Mortality rate?
Acute Disseminated Encephalomyelitis
- acute monophasic demyelinating disease that follows a viral illness (rarely after immunization).
- How long does it take to develop? 7-14 days after illness
- symptoms include: lethargy, headache, coma
- Mortality rate? 20% die. 80% recover
Acute Disseminated Encephalomyelitis
- Morphology
- histology
Acute Disseminated Encephalomyelitis
- Morphology
- histology: myelin loss with relative preservation of axons in white matter
- all lesions appear similar (this is different than MS)
Acute Necrotizing Hemorrhagic Encephalomyelitis
- definition:
- almost always preceeded by _______
- mortality rate:
- histology:
Acute Necrotizing Hemorrhagic Encephalomyelitis
- definition: Fulminant (sudden/severe) syndrome of CNS demyelination of young adults and children
- almost always preceeded by upper respiratory infection
- mortality rate: high fatality rate
- histology: similar to acute necrotizing hemorrhagic encephalomyelitis but more severe and includes damage to small vessels, with subsequent bleeding
Central Pontine Myelinolysis
- definition:
- occurs as a result of:
- associated with?
4.
Central Pontine Myelinolysis
- definition: acute disorder characterized by loss of myelin in the basis pontis and portions of the pontine tegmentum, typically in a roughly symmetric pattern
- occurs as a result of: rapid correction of hyponatremia (usually 2-6 days after the correction)
- associated with?
- other severe electrolyte imbalances
- structures other than the pons
What is this?
- Pathophysiology:
- Clinical features:
- take away point:
Central Pontine Myelinolysis?
- Pathophysiology: rapid increases in osmolality damage oligodendrocytes via uncertain mechanisms
- no inflammation and preservation of neurons and axons
- Clinical features: rapid evolving quadriplegia
- may be fatal
- may lead to severe long-term deficits
- locked in syndrom
- take away point: CORRECT HYPONATREMIA SLOWLY