CNS Flashcards
How do you treat Wernicke encephalopathy?
Thiamine + glucose; glucose alone will precipitate attack b/c thiamine is a cofactor of enzymes responsible for glucose metabolism
What is macular degeneration? What kinds are there?
progressive loss of central vision due to deposition of fatty tissue (drusen) behind the retina (dry MD) and neovascularization of the retina (wet MD)
What causes binasal hemianopia?
pressure to lateral areas of optic chiasm, for example due to calcified carotid arteries
What is an arcuate scotoma?
Damage to a particular region of the optic nerve head → visual defect following the arcuate shape of the nerve fiber pattern
What is Fabry disease?
A sphingolipodosic lysosomal storage disease caused by deficiency in α-galactosidase A. Ceramide trihexoside accumulates. Inheritance: XR
Findings: peripheral neuropathy of hands/feet, angiokeratomas, cardiovascular/renal disease.
A patient presents with an enlarged abdomen, recurrent infections, fatigue, and hip pain. X-ray reveals degeneration of the femur. What lysosomal storage disease is on your differential?
Gaucher disease, caused by an AR deficiency in glucocerebrosidase (β-glucosidase) resulting in the accumulation of Glucocerebroside.
Findings: hepatosplenomegaly, pancytopenia, aseptic necrosis of the femur, bone crises, Gaucher cells.
Treat with glucocerebrosidase
What is the typical microscopic finding in the blood smear of Gaucher disease?
Gaucher cells: lipid-laden macrophages resembling crumpled tissue paper
What is the classic eye finding in Tay-Sachs disease? What other lysosomal storage disease also presents with this finding, and how do you differentiate the two diseases?
Cherry red spot on macula; also occurs in Niemann-Pick disease. However, Niemann pick patients also have hepatosplenomegaly.
What is delirium tremens?
A fluctuant arousal level after acute intoxication. It begins 48-72 hours after last drink and is potentially fatal.
What is generally the first symptom of alcohol withdrawal?
Termulousness
What part of the cortex does the olfactory tract project to?
Piriform cortex (primary olfactory cortex)
What two cranial nerves can be affected by CPA tumors?
VII and VIII
What viral encephalitis in immunocompromised patients is characterized by multinucleated giant cells?
HIV encephalitis
What is alteplase?
tPA!
What functions are associated with the premortor cortex? What happens when there is a lesion here?
coordinates movement of the hands;
lesion → motor apraxia (uncoordinated and nonpurposeful hand movement); may also affect the complex activities related to speech, voluntary eye movement and head rotation
What cells give rise to medulloblastomas?
primitive cells in the cerebellum
Does consciousness waver in delirium?
No, awareness might fluctuate however
What types of drugs cause dystonia?
dopamine receptor blocking drugs or other dopamine antagonists (especially high potency antipsychotics s.a. haloperidol and fluphenazine; this is an EPS)
What are two characteristic symptoms of Lesch-Nyhan syndrome? What accumulates in the blood?
Self-mutilation (e.g. constantly banging head, biting fingers, lips), gouty arthritis; monosodium urate builds up because of loss of purine recycling
In the sympathetic system, what is the post-ganglionic NT released onto cardiac and smooth muscle? Sweat glands? Renal vasculature?
Cardiac/smooth mm.: NE
Sweat glands: Ach
Renal vasculature: Dopamine
What is bromocriptine?
a dopamine agonist
What are the 3 dopamine systems in the brain, and what disease is associated with each?
- Mesolimbic-mesocortical: schizophrenia
- Nigrostriatal: parkinson’s
- Tuberoinfundibular: hyperprolactinemia
What is the main cause of death in TCA overdose?
inhibition of fast Na+ channels in cardiac myocytes → cardiac arrhythmias and refractory hypotension
What is pentazocine?
an opioid with partial agonist and weak antagonist activity at mu receptors designed for analgesia w/out abuse potential: will cause withdrawal in ppl tolerant/dependent on opioids
What is the difference b/w tolcapone and entacapone?
both are COMT inhibitors which prevent Levodopa degradation but entacopone only works peripherally while tolcapone works both centrally and peripherally
