Flashcards in Neuro Deck (304)
A Catechol-O-methyl-transferase (COMT) inhibitor that helps increase the bioavailability of levodopa by inhibition PERIPHERAL methylation. Tolcapone does both peripheral and central but associated with hepatotoxicity.
Carbamazepine mech and SE's?
Blocks voltage-gated Na+ channels in cortical neurons. Bone marrow suppression, hepatotoxic, SIADH.
Two major mechs of diabetic neuropathy?
Glycoslyation leads to thickness, hyalinization, and narrowing of arterial walls -> ischemic damage. Accumulating glucose as sorbital -> inc. cell osmolarity -> osmotic dmg to axons and Schwann cells. Retina, renal papilla, and scwhann cells have DEC. activity of sorbitol dehydrogenase, which prevents clearance of sorbitol into fructose.
Genetics affecting course of Alzheimers?
Early onset associated with APP (21), presenilin-1 (14), and preseinili-2 (1). Late onset with ApoE4 (19). ApoE2 (19) appears to be protective
Senile plaques vs. neurofibrillary tangles
Senile plaques are extracellular Beta-amyloid core. amyloid-Beta comes from cleavage of amyloid precursor protein (APP). Neurofibrillary tangles are INTRAcellular, hyperphosphorylated TAU protein = insoluble. Tangles correlate to degree of dementia.
Frontotemporal dementia vs. Lewy body dementia
Personality and parkinsonian vs. Visual hallucination -> parkinsonian. Pick bodies (spherical tau protein aggregates) + fonrtotemporal atrophy vs. alpha-synuclein defect.
Acute inflammatory demyelinating polyradiculopathy
Most common Guillan-Barre variant. Autoimmune condition associated w/ infection (Campy and CMV) -> destruction of Schwann cells leading to a simmering ascending muscle weakness/paralysis starting from lower extremities. Autonomic findings! Tx - respiratory support, plasmapheresis, IVIG. LP shows increased protein with NORMAL cell count and increased protein.
Progressive multifocal leukoencephalopathy. Destruction of OLIGO's associated with JC. Found in AID's and inc. risk with natalizumab (MS drug). Usu. fatal.
Acute disseminated encephalomyelitis. After infection (measles, VZV) or vaccination (rabies, smallpox), multifocal perivenular inflammation and demyelination
AR, arylsulfatase A deficiency -> buildup of sulfatides -> impaired myelin sheet production -> central and peripheral demyelintation with ATAXIA and dementia. Many-colored Arya becomes ataxic in the sulfur pits.
Progressive hereditary nerve disorder 2/2 defective protein production for structure or function of peripheral nerves or myelin. Typically AD, scoliosis, high or flat arches
Galactocerebrosidase (Gaucher is glucocerebrosidase) -> buildup of galactocerebroside and pyschosine -> myelin destruction -> peripheral neuropathy, dvpt delay, optic atrophy, globoid cells. Krabs are delayed.
X-linked! Metabolism of VLCFA's -> buildup in nervous, adrenals (crisis), testes. ADRENO! luekodystrophy.
Continuous seizure for > 30 minutes or recurrent sz without regaining consciousness between sz. Emergency
Myoclonic vs. tonic-clonic vs. tonic vs. atonic sz.
Myoclonic are quick, repetitive jerks while tonic-clonic are grand mal alternating stiffening and movement. Tonic sz = stiffening. Atonic sz = "drop" sz.
Etios of sz for children?
Genetic, infection (febrile), trauma, congenital, metabolic
Cluster vs. Tension vs. Migraine HA's regarding DURATION
Cluster - 15min-3 hrs repetitive. Tension HA > 30 min and constant. Migraines are 4-72 hours.
Cluster HA vs. trigeminal neuraglia
TN produces repetitive shooting pain in distribution of CN V typically lasting < 1 min. Cluster HA pain is > 15 min.
Tx for cluster headaches?
Inhaled oxygen and sumatriptan vs. analgesics or amitriptyline for chronic pain
Peripheral vs. central vertigo
Peripheral is more common (inner ear etio). Positional testing leads to a delayed horizontal nystagmus. Central is brain stem or cerebellar with directional change of nystagmus, dipolopia, dymetria, immediate nystagmus with positional testing
Sporadic, port-wine Stain, Tram track, Unilateral, Retardation, Glaucoma, GNAQ, Epilepsy. (SSTURGGE). Activating mut -> dvpt anomaly of neural crest derivatives. Port-winte in V1/V2 distribution. Ispsi leptomeningeal angioma -> sz/epilepsy. Congenital NON-inherited. GNAQ sporadic.
HAMARTOMAS = Hamartomas in CNS/skin, Angiofibromas, MR, Ash-leaf spots, cardiac Rhabdomyoma, TS, autosomal dOminant, Mental retardation, renal Angiomyolipomas, Sz, Shagreen patches. Increased subependymal astrocytomas.
Cafe-au-lait, Lisch nodules, NF's in skin, optic gliomas, pheochromocytomas. NF1 is a tumor suppressor gene (Ras regulator) on chromosome 17.
Cavernous hemangiomas in skin, mucosa, organs, b/l RCC, hemangioblastoma in retina, brainstem, cerebeullum, and pheochromocytomas. AD. VHL is tumor suppressor on chromsome 3 -> constitutive HIF (transcription factor) expression -> angiogenic growth factors
Hemispheres, "Butterfly glioma," Astrocytes stain'd for GFAP, pseudopalisading pleomorphic tumor cells with central areas of necrosis
Arachnoid cells, EXTRA-exial. Dural-tail. Often asymptomatic with sz or focal neuro. Path w/ spindle cells concentrically and Psammoma bodies
VHL associated when w/ retinal angiomas. Cerebellar. Often produce EPO => secondary polycythemia. Path - closely arranged, thin-walled caps with minimal parenchyma
Cerebellopontine angle. Schwann cell. S100 POS. B/l acoustic schwannomas found in NF-2.
Rarer, slower growing. Frontal lobe. Path - fried egg cells (oligo's) and chicken-wire capillary pattern. Often calcified.