Epilepsy Flashcards

1
Q

Define epilepsy

A

Occasional, sudden, excessive, rapid and local discharges of grey matter
Recurring tendency to seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the prevalence of epilepsy?

A

1% population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the underlying mechanism in epilepsy?

A

Local loss of membrane potential homeostasis starts at focal point
Relatively small number of neurones form generator site
Neurones heavily depolarise, hyperactivity spreads via synaptic transmission to other neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do voltage gated Na+ channel blockers work?

A

Target high-frequency firing neurones, as they only get access to their binding sites during depolarisation
Once the neurone membrane potential is back to normal, the blocker detaches from the binding site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a partial seizure?

A

Focal onset

Features refer able to a part of one hemisphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the difference between simple and complex partial seizures?

A

Complex = awareness impaired, post-Ictal symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are primary generalised seizures?

A

Simultaneous onset of electrical discharge throughout the cortex
No localising features

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the different types of primary generalised seizures?

A
Absence
Tonic-clonic
Myoclonic
Atonic
Infantile spasms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are absence seizures?

A

Brief pauses in activity, then carries on

Presents in childhood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is aura?

A

Part of the seizure
Patient aware of it
May be a strange feeling in the gut, deja vu, strange smells or flashing lights

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are common post ictal symptoms?

A
Headache
Confusion
Myalgia
Sore tongue
Temporary weakness
Dysphasia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the causes of epilepsy?

A

2/3 idiopathic
Cortical scarring, SOL, stroke
Sarcoidosis
SLE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give some non-epileptic causes of seizure

A

Trauma, stroke, haemorrhage, raised ICP, alcohol / benzo withdrawal
Metabolic disturbance: hypoxia, sodium, glucose, uraemia
Liver disease
Infection
Drugs: TCAs, cocaine, tramadol
Pseudo seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 key questions in diagnosing epilepsy?

A

Are these really seizures?
What type of seizure is it?
Any triggers?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do you assess a first ever seizure?

A

Is it really their first?
Was the seizure provoked - think about non-epileptic causes
Prompt investigation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What counselling is appropriate for seizures?

A

Dangers of swimming, driving, heights, bathing
Employment, sports, insurance, conception
DVLA must be informed, can’t drive until seizure free for 1 year

17
Q

How do you manage an acute seizure?

A
Seizure lasting more than 5 mins or more than 3 in 1hr
Buccal midazolam or rectal diazepam
IV lorazepam if IV access
Protect from injury
Maintain airway
18
Q

What are first line treatments for tonic-clinic seizures?

A

Sodium valproate

Lamotrigine

19
Q

What are first line for absence seizures?

A

Sodium valproate

Lamotrigine

20
Q

What medication is first line for partial seizures?

A

Carbamazepine

21
Q

How are epilepsy medications managed?

A

1 drug if possible
Slowly build up doses until seizures controlled
Changing: start 2nd until max dose reached, then withdraw old drug

22
Q

How does carbamazepine work?

A

Voltage gated sodium channel blocker

NB also CYP inducer

23
Q

What are the side effects of carbamazepine?

A
Leukopenia
Diplopia
Blurred vision
Impaired balance
Drowsiness
24
Q

What is the mechanism of action of Lamotrigine?

A

Voltage gated sodium channel blocker

25
Q

What are the side effects of Lamotrigine?

A
Maculopapular rash
Diplopia
Blurred vision
Tremor
Vomiting
Agitation
Aplastic anaemia
26
Q

How does levetiracetam work?

A

Inhibits presynaptic calcium channels reducing neurotransmitter release

27
Q

What are the side effects of levetiracetam?

A
Psych eg depression
D & V
Dyspepsia
Drowsiness
Diplopia
Blurred vision
28
Q

How does phenytoin work?

A

Voltage gated sodium channel blocker

NB CYP inducer

29
Q

What are the side effects of phenytoin?

A

Decreased intellect
Depression
Gum hyper trophy
Polyneuropathy

30
Q

How does phenytoin toxicity present?

A
Nystagmus
Diplopia
Tremor
Dysarthria
Ataxia
31
Q

How does sodium valproate work?

A

Increases GABA-mediated inhibition of AP transmission by inhibiting activation of GABA and stimulating GABA synthesis
ALSO VGSC blocker

32
Q

What are the side effects of sodium valproate?

A
Increased appetite
Liver failure
Pancreatitis
Reversible hair loss
Oedema
Ataxia
Teratogenic
Tremor
Thrombocytopenia
Encephalopathy
33
Q

What AED is best in women of childbearing age?

A

Lamotrigine

34
Q

What is the risk of feral abnormality in epilepsy?

A

5%

35
Q

What AEDs might affect the pill?

A

Carbamazepine

Phenytoin

36
Q

What is the criteria for stopping AEDs?

A

Normal CNS exam
Normal IQ
Normal EEG
Seizure free for >2 yrs

37
Q

What are the components of a good epilepsy review?

A
Seizure control
Daily life
DVLA
First aid for carer / relatives
Medications
Women of childbearing age