Hi Yield 14.0-14.4

mhewett's version from 2016-06-29 16:03

Section 14.0 Brain Tumors

Question Answer
What type of headaches do pts with brain tumors get?positional headaches (when head is lower than torso)
Other than headaches, what other symptoms can pts with brain tumors get?focal neurologic deficits or new-onset seizures

Section 14.0.1 Neural Tube Derived Brain Tumors (Gliomas)

Question Answer
What is a glioma?forms from tissue that arose from the neural tube; affects mostly males (except oligodendroblastomas affect both genders equally)
What are the 2 most common types of astrocytomas?fibrillary astrocytoma and pilocytic astrocytoma
What type of neural tube derived brain tumor accounts for 80% of all adult primary brain tumors?Fibrillary Astrocytoma
Where are fibrillary astrocytomas located?cerebral hemispheres
What are the 3 types of fibrillary astrocytomas?low grade astrocytoma- static or slow progressing before rapid deterioration
anaplastic astrocytoma- more aggressive
glioblastoma multiforme- most common; extremely high grade; both hemispheres --> butterfly; fatal
What tumor presents a pseudopalisading, butterfly shaped tumor that involves both cerebral hemispheres?Glioblastoma multiforme
Where do pilocytic astrocytomas occur and what age do they affect?cerebellum; children and young adults
How do pilocytic astrocytomas appear?cystic with cells that have long thin hair-like processes; grows slowly
Most common childhood brain tumormedulloblastoma
Where do medulloblastomas occur?cerebellum, midline
How do medulloblastomas present?rapid growth may block CSF flow (causing hydrocephalus)
extremely cellular, with sheets of anaplastic cells
VERY poorly differentiated
dissemination through CSF common
highly malignant
Who does oligodendrogliomas affect?middle aged ppl
How does oligodendrogliomas present?calcifications common; occurs in cerebral white matter; less aggressive; often causes seizure
What type of tumor presents with a "fried egg" appearance on histologic exam?Oligodendrogliomas
Where do ependymomas arise from?ependymal lining of the ventricular system, so CSF dissemination is common
How does it present in children and adults?children: in 4th ventricle
adults: spinal cord
may see ependymal rosettes (canals) or perivascular pseudorosettes

Section 14.0.2 Neural Crest Derived Brain Tumors

What is the histologic presentation of a meningioma? Whirling pattern and psammoma bodies (laminated calcifications)
What disease is associated with both meningiomas and schwannomas? Neurofibromatosis 2 d/t loss of NF2 gene tumor suppressor

Section 14.0.3 Ectoderm Derived Brain Tumors

From what do craniopharyngiomas arise and in what population are they seen? Rathke's pouch remnants; Childhood or adolescence
What type of vision disturbance does a pituitary adenoma cause and why? Bitemporal heteronymous hemianopsia (loss of peripheral vision); d/t mass effect of the tumor on the optic chiasm
What symptoms are associated with prolactinoma? Amenorrhea, Galactorrhea, Loss of libido, Infertility, Visual disturbance (mass effect)
What does a corticotroph tumor secret in excess? ACTH resulting in excess cortisol

Section 14.0.4

With what disease is hemangioblastoma associated? Is it benign/malignant? Life threatening? von Hippel-Lindau disease; Life threatening d/t mass effect in brain but otherwise benign

Section 14.1 Primary Nervous System Disorders

Question Answer
What is a primary nervous system disorder?diseases of the peripheral or central nervous system that is d/t pathology originating in the nervous tissue itself

Section 14.2 CNS Degeneration

Question Answer
How long is the symptomatic course of Alzheimer's and what is the usual cause of death?10 years; pneumonia
What part of the brain is affected by Alzheimer's?Nucleus basalis of Meynert - marked decrease in neurons
What gene/allele/chromosome increases the risk of Alzheimer's? What does the gene do?Apolipoprotein E gene (on the Epsilon4 allele of Chromosome 19); ApoE binds amyloid beta protein plaques
What changes are seen histologically in a pt with Alzheimer's?Hint: 3 changes - Senile plaques (amyloid beta protein in spheres); Neurofibrillary tangles (tau protein); Hirano bodies (eosinophilic rods in hippocampal neurons)
What population is most at risk for developing Alzheimer's and why?Down's Syndrome d/t trisomy of chromosome 21 which carries the amyloid precursor protein (APP)
What neurotransmitter will be decreased in Alzheimer's?ACh
What 2 drug classes are used to manage Alzheimer's?cholinesterase inhibitors (donepezil, galantamine, rivastigmine) +/- NMDA receptor antagonist (memantine)
What is Pick's disease?frontotemporal dementia affecting mostly females that progresses quickly (2-3 yrs)
What is seen histologically with Pick's?Pick bodies (pink inclusion bodies comprised of tau protein in large ballooned cells)
What areas of the brain are affected by Parkinson's and what will you see on biopsy?Substantia nigra (loss of dopamine production) which causes loss of locus ceruleus (dependent on dopamine); + Lewy bodies (pink eosinophilic inclusions of alpha synuclein)
Where are Lewy bodies first formed and what symptom do they cause?Olfactory bulb and dorsal motor nucleus of the vagus; Results in changes in sense of smell - one of first symptoms
What areas of the spinal cord are affected in ALS and are they UMN or LMN? corticospinal tract - UMN; Anterior horn cells - LMN
How does ALS first present?initially with asymmetric weakness in hands with propensity for dropping objects, along with cramping of arms and legs. Eventually, fasciculations.
What are the signs of a LMN lesion? UMN lesion signs?LMN: decreased DTRs, weakness, fasciculations, and symmetrical mm atrophy
UMN: increased DTRs, spasticity and Babinski's, loss of fine motor dexterity
What is Huntington's disease?autosomal dominant, progressive degeneration and atrophy of the caudate nucleus, especially putamen and frontal cortex
What gene does Huntington's affect?mutation of the HD gene located on chromosome 4 causing a trinucleotide repeat of CAG
What neurons are affected in Huntington's dz?Cholinergic and GABAergic neurons - primarily the medium spiny striatal neurons responsible for modulating motor output from the basal ganglia
What symptoms are seen in Friedreich's Ataxia?Ataxia, Dysarthria, Decreased DTRs, Babinski, Sensory and proprioceptive loss, Pes cavus, Progressive kyphoscoliosis, T1DM, Cardiomyopathy (often the cause of death), Degeneration of sensory peripheral neurons and dorsal root ganglia
What chromosome/trinucleotide repeat/deficiency is associated with Friedreich's Ataxia?Chromosome 9; GAA repeat; Deficiency in frataxin (autosomal recessive; d/t mitochondrial dysfunction)
What is Binswanger's disease?associated with long-standing htn; characterized by multiple lacunar infarcts and progressive demyelination of subcortical area; marked by progressively worsening confusion with concomitant mood disorder
What is Progressive Bulbar Palsy?brainstem and cranial nerve degeneration, resulting in diarrhea, respiratory difficulties, difficulty swallowing
What is Werdnig-Hoffman syndrome?autosomal recessive; Infantile spinal muscular atrophy d/t destruction of the anterior horn cells of the spinal cord

Section 14.3 Demyelinating Diseases

Question Answer
What HLA is MS associated with?HLA-DR2
What will appear on the MRI for an MS pt?+ plaques in white matter, especially around ventricles and optic nerve
What test is confirmatory for MS after this suspicious MRI?oligoclonal bands in CSF
Charcot's triad for MSnystagmus, intention tremor, scanning speech
What is Devic's syndrome?bilateral optic neuritis followed in days/weeks by transverse myelitis (CSF high in polys & protein) d/t demyelination of the optic nerve and spinal cord
Guillain-Barre follows what 3 things?viral infection (influenza) OR immunization OR campylobacter gastroenteritis
What change is seen in CSF of a pt with Guillain-Barre?Albumino-cytologic dissociation - d/t significantly increased protein concentration with only mild increase in cell count of CSF
What is adrenoleukodystrophy?X linked deficiency in peroxisomal transporter enzyme, seen in 10-20 yo, resulting in inability to catabolize very long chain fatty acids so you get extremely hi levels of very long chain FA in serum and inability to use them in lipid metabolism
How does adrenoleukodystrophy present?starts with ADHD, motor sensory asymmetric neuropathy, spastic paraplegia, cortical blindness, later adrenal insufficiency
What is Schilder's disease?variant of adrenoleukodystrophy; rare; mimics MS but radiologically shows 1-2 very large plaques of demyelination in cerebral hemispheres
What sphingolipidosis disorder results in a deficiency of arylsulfatase A?Metachromatic leukodystrophy
How does metachromatic leukodystrophy present?AR; forgetfulness, poor school/job performance, personality changes, psych problems; then ataxia, motor problems, mask facies, strange postures; progresses to dementia, paralysis, muteness
CSF contains high protein content
What is subacute combined degeneration (SCD)?d/t vit B12 deficiency featuring demyelinatino and destruction of spinal cord post columns and later corticospinal tract (so both ascending and descending tracts)
How does SCD present?distal paresthesias, weak, unsteady gait, +/- megaloblastic anemia; progresses to spastic weakness of legs and eventually paraplegia
What virus is associated with Progressive Multifocal Leukoencephalopathy (PML)?JC virus (papovavirus) causing complete destruction of all oligodendrocytes; only occurs in the context of severe immunosuppression
How does PML present?MRI shows global white matter atrophy; similar to MS but will have dementia and aphasia early on; death in 6-12 mo

Section 14.4 Some Alcohol Mediated CNS Disorders

Question Answer
Alcohol withdrawal may result inseizures and hallucinations (including delirium tremens)
What causes hepatic encephalopathy?systemic delivery of ammonia and other bowel toxins d/t inefficient removal of substances by a failed (cirrhotic) liver
How does hepatic encephalopathy present?acute confusion, asterixis
What is the difference in Wernicke's syndrome vs Korsakoff's encephalopathy? What is the deficiency?Vitamin B1 (Thiamine) deficiency
Wernicke's: confabulation, focal hemorrhage and necrosis of mammillary bodies, ophthalmoplegia, ataxia, REVERSIBLE
Korsakoff's: M-phage accumulation at hemorrhage sites of Wernicke's in areas that eventually become open cysts resulting in psychosis and dementia, IRREVERSIBLE
What is alcoholic cerebellar degeneration?the vermis atrophies secondary to alcohol toxicity. Features ataxia of the trunk
What is alcoholic neuropathy?d/t toxic effects of alcohol. First, vibration sense is lost, then painful sensory disturbances occurs, sometimes with motor problems
What is Marchiafava-Bignami Disease?d/t ingestion of large quantities of red wine. Features degeneration of corpus callosum resulting in frontal lobe dementia