PH2113 - Neurodegenerative Disease and Epilepsy 9 Flashcards
Give examples of Transmissible Spongiform Encephalopathies
Kuru
- Papua New Guinea
Sporadic CJD
- most common
- 1/1,000,000
Latrogenic CJD
Variant CJD
What are Transmissible Spongiform Encephalopathies (TSE)?
Prion diseases that can be passed on
What are the symptoms of Transmissible Spongiform Encephalopathies?
Long incubation period which has given rise to the term “slow infection”
- several years
Loss of muscle co-ordination
- difficulty in walking
- functional disorder of the cerebellum
Dementia
- initial loss of memory
- diminished intellect
- poor judgement
Progressive insomnia
- marked reduction or loss of slow-wave and REM phases
New variant CFM
- typically stars with depression
What are the pathologies of Transmissible Spongiform Encephalopathies?
PrPSc (prion protein SC) accumulates within the neutrophil where it causes
- astrocyte gliosis
- depletion of dendritic spines in neurones
- formation of numerous vacuoles in the cerebella cortex
- spongiform encephalopathy
Amyloidosis
- deposition of amyloid in plaques
- proteins in beta sheet
- discrete eosinophilic glassy-appearing masses
- radiating amyloid fibrils at their periphery
What are the current treatment for vCJD?
Organic Polyanions
- pentosan polysulphate
- intracerebroventricular drug administration may prolong life
- ICV
Flupirtine
Quinacrine
- 300mg/day
- compassionate treatment of CJD
- already approved
- reported in a single case study
- transient improvement in akinetic and arousal
- absence of placebo controlled studies
What is a seizure?
A symptom
An acute, finite event
Response of the brain to various stimuli
Excessive discharge of cerebral neurones
Transient paroxysm of uncontrolled discharges beginning at the epileptic focus
- discernible by the person experiencing the seizure and/or observer
- localised
- spread to adjacent areas
- spread to whole brain
Absence seizures the discharge is regular and oscillatory
What is epilepsy?
A chronic brain disorder of various causes
- characterised by recurrent seizures
What is the incidence of epilepsy?
Worldwide
- 25 to 65 million people
USA
- 1.7 million people
UK (non-febrile)
- 350,000 to 400,000 patients
- total cumulative = 1,500,000 patients
What are the three types of seizures?
Focal onset
Generalised onset
Unknown onset
What are the two types of focal seizures?
Aware
Impaired awareness
What are the signs on an EEG of a focal aware seizure?
Initial activation of a group of neurones in part of one of the cerebral hemispheres
- motor
- sensory
- depends on location of foci
CONSCIOUSNESS ALWAYS INTACT
What is a Jacksonian seizure?
Focal aware seizures which spread over the cortex
What is the difference between a focal aware and focal impaired awareness seizure?
Consciousness disturbed
- sense of distortion of time or reality
- confusion
- complete loss of consciousness
Automatisms
- fumbling with clothes
- licking lips
- turning head
After seizure
- confusion
- amnesia
Frequent correlation with temporal lesions
- EEG shows temporal spikes
What is a non-motor (absence) seizure?
Clinical and EEG data showing bilateral involvement
- both sides of brain
Very brief “attacks”
- seconds to a few minutes
Clinically characterised by the sudden interruption of the ongoing activities that are reassumed once the attack is over
Sometimes associated with some automatisms
- fluttering of the eyelids
- gaze deviation
NOT NOTICED BY PATIENT
What is a motor (tonic-clonic) seizure?
Clinical and EEG data showing bilateral involvement
Sudden loss of muscle tone and consciousness
- fall to floor
Immediately clonic movements of extremities
- rhythmic shaking
- upwards gazed deviation
- absence of respiratory movements
- incontinence may occur
- lesions of the tongue are not infrequent
Once seizure ends, period of unconsciousness and amnesia
- less than 5 minutes
- call 999 if longer
