10. MS and Neurodegeneration Flashcards
What is MS?
Immune-mediated destruction of myelin in the CNS
What cells produce myelin in the CNS?
Oligodendrocytes
What are the symptoms of MS?
Visual loss Acute transverse myelitis Trigeminal neuralgia Diplopia, balance disturbance and vertigo Bladder dysfunction
What is Lhermitte’s sign?
Neck flexion causes rapid tingling or electric shock feeling passing from spine to limbs
What is Uhtoff’s phenomenon?
Symptoms are exacerbated at increased temperatures
What is the classification of MS?
Clinically isolated syndrome
Relapsing and remitting
Primary progressive
Secondary progressive
What is the composition of an active MS plaque?
Lymphocytes
Macrophages containing myelin debris
How is active MS detected on an MRI?
BBB is disrupted to allow inflammatory cells through, meaning contrast will also seep through, causing enhancement
What is the composition of a chronic MS plaque?
Reduced myelin
Astrocytes proliferation
Gliosis
What are the genetic components of MS?
HLA
IL-2 and IL-7 receptors
What locations are MS plaques commonly found in?
Near ventricles Optic nerves Brain stem Cerebellum Spinal cord
How is MS diagnosed?
Clinically
McDonald criteria: plaques disseminated over time and space
CSF analysis
Visually evoked potential
What is seen in CSF in MS?
Mildly increased protein level
Oligoclonal bands
1/3 of cases show moderate pleocytosis
What is the acute management of MS?
Steroids
Plasma exchange
What is the long term management of MS?
Disease modifying therapy started ASAP
What is the definition of neurodegeneration?
Progressive dysfunction and death of neurons
What are the features of neurodegeneration?
Neuronal loss
Gliosis
Intracellular accumulation of abnormal proteins
What does the presence of ubiquitin suggest?
Increased protein elimination; may be a protein accumulating that hasn’t been recognised yet
What is the usual function of tau?
Stabilises microtubules in neurons
What part of the brain is affected in Alzheimer’s disease?
Hippocampus
What proteins are deposited in Alzheimer’s disease?
B-amyloid
tau
What is the macroscopic appearance of the brain in Alzheimer’s disease?
Cortical atrophy and ventricular enlargement
Widening of cerebral sulci
What is the microscopic appearance of Alzheimer’s disease?
Neuritic plaques (extracellular) Neurofibrillary tangles (intracellular)
What proteins are deposited in frontotemporal lobar degeneration?
TDP43
Tau
What is the difference between delirium and dementia?
Delirium is an acute disorder of attention and global cognition and is reversible
Dementia is a progressive decline in at least 2 cognitive areas, irreversible
What investigations should be done into dementia?
Exclude acute causes Detailed history and cognitive assessment Exclude metabolic causes Autoantibodies Brain imaging to exclude stroke Rarely biopsy
What are the cardinal features of Parkinson’s disease?
Bradykinesia
Resting tremor
Rigidity
What protein is deposited in Parkinson’s disease?
a-synuclein, which accumulates to form Lewy bodies within neurons in the substantia nigra
What protein accumulates and where in motor neuron disease?
TDP43 in anterior horn cells
