Neuropathology 2 Flashcards
What is chorea?
Diseases associated?
Involuntary, jerky, purposeless movements that arise from basal ganglia lesions
Inherited disorders: HD, Neuroacanthocytosis, Wilson’s disease
Infectious - strep infection - rheumatic fever
Drug induced chorea - neuroleptics (phenothiazines, haloperidol), phenytoin, oral contraceptives in women with SLE, L-dopa and DA agonists, cocaine
What is athetosis
Not fixed, snake like writhing, especially of the fingers
Basal ganglia lesions, antipsychotics e.g. haloperidol
What is hemiballismus? Causes
Treatments?
Sudden, uncontrolled flailing of one limb due to lesions in contralateral STN (subthalamic nucleus)
Interrupts inhibitory indirect pathway
Treatments: Haloperidol, phenothiazine
Broca’s aphasia?
Motor/nonfluent/expressive aphasia - occurs in inferior frontal gyrus, brodmann 44, patients are nonfluent, with good comprehension, impaired repetition, speak in short monosyllabic words, aware of deficit, frustrated
Assoc. contralateral arm and face weakness
Lesions in superior left MCA
Wernicke’s aphasia?
Superior temporal gyrus, brodmann 22,
Sensory/fluent/auditory aphasia - with impaired comprehension, neologisms, paraphasic errors, and impaired repetition
Speech is fluent but nosensicl ‘word salad”
Unaware of deficit
Assoc. visual deficit, contralateral RU quadrantanopia, due to meyer’s loop in temporal lobe, alexia
Conduction aphasia?
Lesions to arcuate fasciculus that connects the two language centers, poor repetition with intact comprehension and fluent speech
Cannot name objects
Global aphasia?
Both speech and comprehension affected, large perisylvian or separate frontal and temporal lesions
Assoc. right hemiplegia, right hemianesthesia, and homonymous hemianopia
Degenerative diseases
Classic symptoms with cerebrum lesions?
CST? Basal ganglia? cerebellum?
CST - motor deficits
Cerebrum - personality changes, memory loss, seizures cognitive dysfunction
Basal ganglia -movements disorders
Spinocerebellar/cerebellum lesions - manifest in ataxia
Name 3 diseases associated with motor neuron lesions?
- ALS
- Werdnig-Hoffman syndrome (floppy baby)
- Poliomyelitis
What is ALS? Features?
- Amyotrophic Lateral Sclerosis - associated with UMN and LMN signs sparing sensation, 40-60 years age of onset, assoc. chr. 21, SOD1 gene
- UMN signs - spasticity, +Babinski, hyperreflexia
- LMN signs - thenar atrophy, muscle weakness, denervation atrophy
- Rapidly fatal due to resp. failure - use Riluzole to delay ventilator/tracheostomy use
What is Werdnig-Hoffman disease?
Features? Pathology?
- Autosomal “recessive inheritance that manifests at birth as “floppy baby syndrome”
- Tongue fasciculations, LMN disease
- Degeneration of anterior horn cells
- no UMN, or CST degeneration
- congenital variant of ALS with only LMN signs
- Defect in gene turns of peri-natal apoptosis
- Median age of death - 7 years
Poliomyelitis? features? causes? treatment?
-Follows infection (fecal-oral) with poliovirus
Replicates in oropharynx and small intestine before hematologic spread to CNS, presents with LMN signs
-CSF with lymphocytic pleocytosis, slight increase in protein
-virus recovered from stool or throat
-Degeneration of anterior horn cells
-Treatment: hospitalize with strict bed rest to reduce paralysis, ventilation to treat resp. muscle weakness
Alzheimer’s disease? features? presentation?
- Slow progressive mental deterioration with loss of short term memory, anosmia, language difficulties and planning skills, decline in executive function
- Spares primary sensory and motor areas
- Generalized cerebral atrophy –> widened sulci, hydrocephalus ex vacuo
- Most common dementia in elderly
Alzheimer’s disease? Inheritance?
- Familial form (10%) associated with early onset (before 40 yrs)
- Genetic causes - presenilin 1 and 2 on chr. 1 and 14 - causing hyperphosphorylated tau and neurofibrilliary tangles, APOE4 allele on chr. 19, p-APP on chr. 21
- p-APP increases amount of APP, trisomy 21 is assoc. with early -onset AD (30-40 yrs)
Alzheimer’s disease? Pathology?
- senile plaques (Beta-amyloid surrounded by dystrophic neuritis in extracellular space
- neurofibrillary tangles (intracellular abnormal tau protein, silver stain positive)
- Beta-amyloid is toxic when deposited on neurons and cerebral blood vessels (cerebral amyloid angiopathy) causing intracranial hemorrhage
- decreased ACh due to loss of cholinergic nuclei in forebrain nucleus basalis of Meynert
Alzheimer’s disease? Treatment?
- Donezepil - ACE inhibitors that cross BBB
- NMDA receptor antagonists - memantine reduce glutamate -mediated excitotoxicity
- Not disease modifying