Motor Neuron Disease Flashcards
initial presentation: crampsm, then atrophy, fasciculations and weakness involving axial and or bulbar musculature with associated UMN findings
preserved muscle stretch reflexes
Amyotrophic Lateral Sclerosis (ALS)
behavioral change (apathy, disinhibition, agitation), lack of insight, blunted emotions > cognitive deficits, alien hand, apraxia, myoclonus, limb rigidity
Fronto Temporal Dementia
What is the protein dysfunction of ALS, where is the build up?
ubiquinated TDP-43»FUS (SOD1 in familial forms)
TDP-43 cellular inclusions
builds up in primary motor cortex, white matter tracts, brainstem motor nuclei, spinal cord anterior horn cells
What are the dysfunctional proteins in FTD?
TAU, TDP-43
What is the function of MUSK in the neuromuscular jxn?
attaches the ACh receptor to the post-synaptic membrane
What is the function of LRP4 in the neuromuscular jxn?
clustering of ACh receptors in post synaptic membrane
how does Botulinum toxin work in the neuromuscular junction?
toxin bind to snare proteins and inhibit ACh vesicles from binding to the presynaptic membrane irreversibly
What food can infant get affected by botulinum toxin by?
honey
Muscle Weakness, Fatigue, pain
speech impairment
Dry mucosa
Lambert - Eaton syndrome
How does Lambert - Eaton Syndrome work? what other disease is LEMS most commonly a/w?
Presynaptic - block voltage gated calcium channels
a/w Small Cell lung Ca
How does Myasthenia Gravis work?
Anti-AChR Ab
Anti-MuSK Ab
What other dysfucntion of MG a/w?
Thymoma - muscle like cells within the thymus
