Neuro-02-Path Flashcards
(42 cards)
1
Q
Dementia
A
- A decrease in cognitive ability, memory, or function with intact consciousness
- Causes:
- Alzheimer’s
- Pick’s disease
- Lewy body dementia
- Creutzfeldt-Jakob disease
- Multi-infarct: second most common cause of dementia in elderly
- Syphilis
- HIV
- Vitamins B1, B3, or B12 deficiency
- Wilson’s disease
- Normal pressure hydrocephalus (NPH)
2
Q
Alzheimer’s disease
A
- Most common cause of dementia in the elderly
- Down syndrome patient’s have an increased risk of developing alzheimer’s
- Familial form (10%) is associated with the following altered proteins:
- Early onset: APP (chromosome 21), presenilin-1 (chromosome 14), presenelin-2 (chromosome 1)
- Late onset: ApoE4 (Chromosome 19)
- ApoE2 (chromosome 19) is protective
- Findings:
- Widespread cortical atrophy
- Decreased ACh levels
- A-beta (amyloid-beta) synthesized by cleaving amyloid precursor protein (APP)
- Senile plaques: extracellular beta-amyloid core with entangled neuritic processes
- Senile plaques may cause amyloid angiopathy, leading to intracranial hemorrhage
- Neurofibrillary tangles: intracellular abnormally phosphorylated tau protein, forming insoluble cytoskeletal elements
- Tangles correlate with degree of dementia
3
Q
Pick’s disease (frontotemporal dementia)
A
- Presentation: Dementia, aphasia, parkinsonia aspects, change in personality
- Findings:
- Pick bodies: spherical tau protein aggregates
- Frontotemporal atrophy
- Spares parietal lobe and posterior 2/3 of superior temporal gyrus
4
Q
Lewy body dementia
A
- Parkinsonism with dementia and hallucinations
- Findings:
- alpha-synuclein defect
- Lewy bodies are in cortex (instead of in basal ganglia, as in Parkinson’s)
5
Q
Creutzfeldt-Jakob disease (CJD)
A
- Rapidly progressive (weeks to months) dementia with myoclonus (startle myoclonus)
- Findings:
- Spongiform cortex
- Prions: PrPc -> PrPsc sheet (beta-pleated sheets resistant to proteases)
6
Q
Multiple sclerosis
A
- Autoimmune inflammation and demyelination of CNS (brain and psinal cor)
- Can present with: Optic neuritis (sudden loss of vision), internuclear opthalmoplegia (MLF syndrome), hemiparesis, hemisensory symptoms, bladder/bower incontinense
- {Charcot’s classic triad of MS is a sin : Scanning speech, Intention tremor (also incontinence and INO), Nystagmus}
- Relapsing and remitting course
- Most often affects women in their 20s and 30s; more common in whites
- Findings:
- Increased protein (IgG) in CSF: oligoclonal bands are diagnostic
- MRI is gold standard
- Periventricular plaques with destruction of axons: areas of oligodendrocyte loss and reactive gliosis
- Treatment:
- beta-interferon
- immunosuppression
- natalizumab
- symptomatic treatment for bladder (catheterization, muscarinic antagonists), spasticity (baclofen, GABA agonist), and pain (opioids)
7
Q
Acute inflammatory demyelinating polyradiculopathy
A
- Most common variant of Guillain-Barre syndrome
- Autoimmune condition that destorys schwann cells, leading to inflammation and demyelination of peirpheral nerves and motor fibers
- Results in symmetric ascending muscle weakness/paralysis beginning in lower extremitis
- Facial paralysis in 50% of cases
- Autonomic function may be severely affected (e.g., cardia irregularities, hypertenstion, or hypotnesion)
- Amost all patients survive, and the majority recover completely after weeks to months
- Associations (no definitive link to pathogens):
- infections (Campylobacter jejuni and CMV), which lead to autoimmune attack of peripheral myelin due to molecular mimicry
- Inoculations
- Stress
- Findings:
- Albuminocytologic dissociation (increased CSF protein with normal cell count)
- Increased protein leads to papilledema
- Treatment:
- Respiratory support is criticall
- Plasmapheresis
- IV immune globulins
8
Q
Progressive multifocal leukocencephalopathy (PML)
A
- Demyelination of CNS due to destruction of oligodendrocytes
- Associated with JC virus
- Seen in 2-4% of AIDS patients (reactivation of latent viral infection)
- Rapidly progressive, usually fatal
9
Q
Acute disseminated (postinnfectious) encephalomyelitis
A
Multifocal perivenular inflammation and demyelination after infection (commonly measles or VZV) or certain vaccinations (e.g., rabies, smallpox)
10
Q
Metachromatic leukodystrophy
A
- Autosomal recessive lysosomal storage disease
- Most commonly due to arylsulfatase A deficiency
- Leads to buildup of sulfatides with impaired production of myelin sheath
11
Q
Charcot-Marie-Tooth disease
A
- AKA, hereditary motor and sensory neuropathy (HMSN)
- Group of progressive hereditary nerve disorders related to defective production of proteins involved in the structure and function of peripheral nerves or the myelin sheath
12
Q
Krabbe’s disease
A
- Autosomal recessive lysosomal storage disease
- Due to deficiency of galactocerebrosidase
- Leads to buildup of galactocerebroside, which destroys myelin sheath
13
Q
Seizures
A
- Synchronized, high-frequency neuronal firing
- Causes of seizures by age:
- Children: genetic, infection (febrile), trauma, congenital, metabolic
- Adults: tumors, trauma, stroke, infection
- Elderly: stroke, tumor, trauma, metabolic, infection
- Partial (focal) seizures: simple partial, complex partial
- Generalized seizures: absence, myoclonic, tonic-clonic, tonic, atonic
14
Q
Epilepsy
A
A disorder of recurrent seizures (febrile seiures are not epilepsy)
15
Q
Status epilepticus
A
- Continuous seizure for > 30 min or recurrent seizurse without regaining consciousness between seizures for > 30 min
- Medical emergency
16
Q
Partial (focal) seizures
A
- Affect 1 are of the brain
- Most commonly originate in medial temporal lobe
- Often preceded by seizure aura
- Can secondarily generalize
- Types:
- Simple partial: consciousness intact; motor, snesory, autonomic, psychic symptoms
- Complex partial: Impaired consciousness; display automatisms
17
Q
Generalized seizures
A
- Diffuse
- Types:
- Absence (petit mal): blank stare, 3 Hz spike-and-wave discharge, no postictal confusion
- Myoclonic: quick, repetitive jerks
- Tonic: stiffening
- Tonic-clonic (grand mal): alternating stiffening and movement
- Atonic: “drop” seizures (falls to fllor); commonly mistaken for fainting
18
Q
General causes of headaches
A
- Pain due to irritation of structures such as the dura, cranial nerves, or extracraianl structures
- Causes:
- Cluster headaches
- Tension headaches
- Migraine headaches
- Subarachnoid hemorrhage
- meningitis
- hydrocephalus
- neoplasia
- arteritis
19
Q
Cluster headache
A
- Unilateral
- 15 min - 3 hrs in duration; repetitive
- More common in males
- Presentation:
- Repetitive brief headaches
- Excruciating periorbital pain with lacrimation and rhinorrhea
- may induce horner’s syndrome
- Treatment:
- Inhaled oxygen
- Sumatriptan
20
Q
Tension headache
A
- Bilateral
- > 30 min (typically 4-6 hrs); constant
- Presentation: Steady pain without photophobia or phonophobia; no aura
21
Q
Migraine
A
- Unilateral
- 4-72 hrs
- Presentation:
- Pulasting pain
- Photophobia or phonophobia
- May have aura
- Due to irritation of CN V, meninges, or blood vessels
- Release of substance P, CGRP, vasoactive peptides
- Treatment:
- Prophylactic: propanolol, topiramaate
- Abortive therapies: Triptans, etc.
22
Q
Trigeminal neuralgia (TN)
A
- Lasts < 1 minute
* repetitive shooting pain in the distribution of CN V
23
Q
Vertigo
A
• Sensation of spinning while actually stationary (can be called “diziness” but it’s different from “lightheadedness”)
24
Q
Peripheral vertigo
A
- More common
- Inner ear etiology: e.g., semicircular canal debris, vestibular nerve infection, Meniere’s disease
- Positional testing reveals delayed horizontal nystagmus
25
Central vertigo
* Due to brainstem or cerebellar lesion: e.g., stroke affecting vestibular nuclei or posterior fossa tumor
* Findings:
* Directional change of nystagmus
* skew deviation
* diplopia
* dysmetria
* Positional testing reveals immediate nystagmus in any direction; may change directions
26
Sturge-Weber syndrome
* Congenital disorder presenting with:
* Port-wine stains (aka nevus flammeus), typically in V-1 ophthalmic distribution
* Ipsilateral leptomeningeal angiomas
* Pheochromocytomas
* Can cause:
* glaucoma
* seizures
* hemiparesis/hemiplegia
* mental retardation
* Occurs sporadically
27
Tuberous sclerosis
* Autosomal dominant disorder of benign tumors
* Can present with: {HAMARTOMAS}
* Hamartomas in CNS and skin
* Adenoma sebaceum (cutaneous angiofibromas)
* Mitral regurgitation
* Ash-leaf spots
* cardiac Rhabdomyoma
* (Tuberous sclerosis)
* autosomal dOminant
* Mental retardation
* renal Angiomyolipoma
* Seizures
28
Neurofibromatosis type I (von Recklinghausen's disease)
* autosomal dominant disorder; 100% dominant; variable expressivity
* 90 % of NF cases
* Caused by mutated NF1 tumor supressor gene on chromosome 17
* Can present with:
* Café-au-lait spots
* Lisch nodules (pigmented iris hamartomas)
* Neurofibromas in skin
* optic gliomas
* Pheochromocytomas
29
Neurofibromatosis type II
* autosomal dominant
* 10% of NF cases
* Caused by mutated NF2 tumor supressor gene on chromosome 22
* Can present with:
* Café-au-lait spots
* Neurofibromas
* bilateral acousitc neuromas
* Meningiomas
* Pheochromocytomas
30
von Hippel-Lindau disease
* Autosomal dominant
* Caused by mutated tumor suppressor VHL gene on chromosome 3
* Can present with:
* Cavernous hemangiomas in skin, mucosa, organs
* Bilateral renal cell carcinoma
* Hemangioblastoma in retina, brainstem, cerebellum
* Pheochromocytomas
31
Metastatic CNS tumors
* 50% of all cns tumors
* Most common metastases that go to brain:
* Lung
* Breast
* Melanoma
* Kidney
32
Glioblastoma multiforme (Grade IV astrocytoma)
* Adult primary brain tumor; most common
* arises from astrocytes; can stain astrocytes for GFAP
* Malignant with < 1 year life expectancy
* Found in cerebral hemispheres and can cross the corpus callosum ("butterfly glioma")
* Histology: see "pseudopalisading" pleomorphic tumor cells that border central areas of necrosis and hemorrhage
33
Meningioma
* Adult primary brain tumor; second most common
* Arise from arachnoid cells
* Typically benign and resectable
* Most often occurs in convexities of hemispheres (near surfaces of brain) and parasagittal region
* Are extra-axial (external to brain parenchyma) and may have a dural attachment ("tail")
* Presentation: often asymptomatic; may present with seizures or focal signs
* Histology:
* Spindle cells concentrically arranged in a whorled pattern
* Psammoma bodies (laminated calcifications)
34
Schwannoma
* Adult primary brain tumor; third most common
* Schwann cell origin; S-100 positive
* Resectable or treated with stereotactic radiosurgery
* Often localized to CN VIII (acoustic schwannoma or acoustic neuroma)
* Usually found at cerebellopontine angle
* Bilateral acoustic schwannomas are found in neurofibromatosis type 2
35
Oligodendroglioma
* Adult primary brain tumor; relatively rare
* Slow growing
* Most often found in frontal lobes
* Histology:
* Chicken-wire capillary pattern
* "fried egg" cells: round nuclei with clear cytoplasm; often calcified in oligodendroglioma
36
Pituitary adenoma
* Adult primary brain tumor
* Most commonly is a prolactinoma
* Presentation:
* bitemporal hemianopsia due to pressure on optic chiasm
* Hyper- or hypopituitarism as sequelae
37
Pilocytic (low-grade) astrocytoma
* Childhood primary brain tumor
* Arises from astrocytes; GFAP positive
* Bening; good prognosis
* Usually well circumbscribed
* In children it's most often found in posterior fossa (e.g., cerebellum)
* May be supratentorial
* Histology: Rosenthal fibers (eosinophilic, corkscrew fibers)
* Gross pathology: cystic and solid
38
Medulloblastoma
* Childhood primary brain tumor
* A form of primitive neuroectodermal tumor
* Highly malignant cerebellar tumor
* Radiosensitive
* Can compress 4th ventricle, causing hydrocephalus
* Can send "drop metastases" to spinal cord
* Histology:
* Homer-wright rosettes
* Small blue cells
* Gross pathology: Solid
39
Ependymoma
* Childhood primary brain tumor
* Derived from ependymal cells
* Poor prognosis
* Most commonly found in 4th ventricle
* Can cause hydrocephalus
* Histology:
* Characteristic perivascular pseudorosettes
* Rod-shaped blepharoplasts (basal ciliary bodies) found near nucleus
40
Hemangioblastoma
* Childhood primary brain tumor
* Most often cerebellar
* Associated with von Hippel-Lindau syndrome when found with retinal angiomas
* Can produce EPO and lead to secondary polycythemia
* histology: foamy cells and high vascularity are characteristic
41
Craniopharyngioma
* Childhood primary brain tumor
* Most common childhood supratentorial tumor (most childhood tumors are infratentorial)
* Derived from remnants of Rathke's puch
* Can also cause bitemporal hemianopsia
* Can be confused with pituitary adenoma
* Calcification is common (tooth enamel-like)
42
Herniation syndrome
* Cingulate (subfalcine herniation) under falx cerebri: can compress the anterior cerebral artery
* downward transtentorial (central) herniation
* Uncal herniation (uncus is part of medial temporal lobe)
* Cerebellar tonsilar herniatio ninto the foramen magnum: comma and death result when these herniations compress the brainstem
