Epilepsy and seizures

Question 1

What is a seizure?

Answer 1

Neurological dysfunction caused by abnormal excess activation of the neuronal pathways

Question 2

What is epilepsy?

Answer 2

Recurrent (>2) unprovoked seizures

Question 3

What is status epilepticus?

Answer 3

State of continued/recurrent seizures with no regaining of consciousness in between

Question 4

What causes seizures in epilepsy?

Answer 4

Normal cortical neuronal communication gone wrong, due to one of three things:

• increased connectivity in neuronal pathways
• increase excitatory transmission (glutamate)
• failure of inhibitory mechanisms (GABA)

Question 5

What are some of the causes in epilepsy?

Answer 5

• stroke
• meningitis
• encephalitis
• malaria
• tumour
• drugs: MAOIs, illicit drugs e.g. cocaine
• alcohol or alcohol withdrawl
• drug withdrawl
• congenital/family history
• vasculitis
• head trauma

Question 6

What proportion of epilepsy cases have no cause found?

Answer 6

~ 50%

Question 7

What is a focal seizure?

Answer 7

A seizure where the excitation is beginning in a specific area e.g. motor cortex or visual cortex

This gives specific symptoms

Question 8

What are some of the symptoms that may be seen in a focal seizure?

Answer 8

Motor: jerking, twitching, rigidity

Sensory: funny taste, aura, visual changes, smell

Psychological: emotion and memory

Question 9

What is the difference between a simple focal seizure and a complex focal seizure?

Answer 9

Simple - no loss of consciousness

Complex - same as simple but impaired consciousness

Question 10

What is focal with secondary generalised seizure?

Answer 10

A seizure that begins as focal but progresses to loss of consciousness and tonic-clonic seizures

Question 11

What is a generalised seizure?

Answer 11

A seziure involving both hemispheres from the beginning of the seizure

Question 12

What forms might a generalised seizure take?

Answer 12

Tonic-clonic

Tonic

Myoclonic

Abscence

Atonic

Question 13

What is a tonic-clonic seizure?

Answer 13

Muscle rigidity (tonic) with superimposed jerking (clonic)

Question 14

What is a tonic seizure?

Answer 14

Muscle stiffness/rigidity

Question 15

What is a myoclonic seizure?

Answer 15

Sporadic jerking

Question 16

What is an absence seizure?

Answer 16

Blank stare

Question 17

What is an atonic seizure?

Answer 17

Complete loss of tone (drop attacks)

Question 18

Which generalised seizure does not involve post-ictal confusion?

Answer 18

Absence seizures

Question 19

Do all generalised seizures cause loss of consciousness?

Answer 19

Yes

Question 20

What are the risk factors for developing epilespy?

Answer 20

Previous head injury

Febrile convulsions as a child

Meningitis

Encephalitis

Previous stroke

Alcohol abuse

Family history

Question 21

What are some of the triggers for a seizure?

Answer 21

Sleep deprivation

Alcohol

Stress

Recreational drugs

Pregnancy

Flashing lights

Current infection

Question 22

In a history from a patient with seizure as the presenting complaint, what would you need to know about the ictal phase?

Answer 22

Where seizure occured?

How long?

Was there altered or loss of consciousness?

Tongue biting or frothing at mouth?

Urinary incontinence?

Cyanosis?

Question 23

What is Todd’s paresis??

Answer 23

Focal weakness in a part of the body following a focal seizure

Question 24

What are some of the differential diagnosis to epilepsy?

Answer 24

Pseudoseizure

Complicated migraine

Carpopedal spasm from hyperventilation

Syncopal episode

Question 25

What are some of the clinical signs of true seizure?

Answer 25

Pupil dilation Hypertension Tachycardia Extensor plantar response Cyanosis/peripheral cyanosis

Question 26

What are some of the biochemical signs of a seizure?

Answer 26

Hypoxia/reduced pO2 Acidosis Increased CK

Question 27

What biochemical abnormalities might cause seizures?

Answer 27

Hyponatraemia Hypocalcaemia

Question 28

How does carbemazepine work in epilepsy?

Answer 28

Blocks voltage dependant Na channels to prevent repetitive neuronal discharge

Question 29

When is carbemazepine used?

Answer 29

Focal seizures Secondary generalised seizures Neuropathic pain

Question 30

What are the side effects of carbemazepine?

Answer 30

Sedation Tremor Weight gain LFT abnormalities Syndrome of inappropriate ADH

Question 31

What monitoring needs to be done with carbemazepine??

Answer 31

Plasma levels for theraputic window

Question 32

What are the uses of sodium valproate?

Answer 32

All types of seizures Mood stabiliser in bipolar disorder

Question 33

What is the mechanism of action of sodium valproate?

Answer 33

Na channel blocker

Question 34

What are the side effects of sodium valproate?

Answer 34

Leucopenia Skin sensitivity to UV light Weight gain Sedation Teratogenicity

Question 35

What is the mechanism of action of phenytoin?

Answer 35

Inhibits the Na channel and prevents spread of seizure activity in the motor cortex

Question 36

When is phenytoin used?

Answer 36

Tonic-clonic seizures Status epilepticus Prophylactic on post-op neurosurgery

Question 37

What are the side effects of phenytoin?

Answer 37

Drowsiness Ataxia Nausea Nstagmus Hypersensitivity syndrome

Question 38

What is anticonvulsant hypersensitivity syndrome?

Answer 38

A drug-induced, multiorgan syndrome which is potentially fatal

Question 39

What are the symptoms of anticonvulsant hypersensitivity syndrome?

Answer 39

Fever Rash Hepatitis Hepatorenal syndrome Haemolysis

Question 40

When is lamotrigine used?

Answer 40

All seizure types Bipolar disorder

Question 41

What are the side effects of lamotrigine?

Answer 41

Skin rash Steven-Johnsone syndrome Hypersensitivity syndrome Dizziness Nausea

Question 42

What drugs can be used to treat focal seizures and/or secondary generalised seizures?

Answer 42

Carbemazepine Sodium valproate Lamotrigine

Question 43

What drugs can be used to treat generalised seizures?

Answer 43

Sodium valproate Lamotrigine

Question 44

How is acute seizure managed?

Answer 44

ABCDE High flow oxygen/non-rebreather mask IV access Midazolam (can be given intranasally/buccally if no IV) Diazepam (can be given per rectum if no IV)

Question 45

What should be done if patient not responding to initial dose of midazolam/diazepam?

Answer 45

Give another dose of midazolam Still fitting - phenytoin

Question 46

What are the complications if a seizure is left untreated?

Answer 46

Hypoxia -\> cerebral ischaemia If \>1hr, cerebral oedema Aspiration pneumonitis Hyperthermia Fractures and dislocations (shoulder)

Question 47

What are the properties of levetiracetam?

Answer 47

Few interactions with other medications Well tolerated, though can cause mood swings

Question 48

What considerations for women are there when prescribing antiepileptic drugs?

Answer 48

Medications can reduce efficacy of OCP Reduced efficacy of morning after pill if taking enzyme inducers Teratogenicity

Question 49

Which drug is extremely teratogenic?

Answer 49

Sodium valproate

Question 50

Which drugs reduce the efficacy of the OCP?

Answer 50

Carbamazepine Phenytoin Oxcarbazepine

Question 51

Which drug can cause Stephens-Johnson syndrome?

Answer 51

Lamotrigine

Question 52

Which drug can cause syndrome of inappropriate ADH?

Answer 52

Carbamazepine

Question 53

Which drug can cause ataxia and nystagmus?

Answer 53

Phenytoin

Question 54

Which drug causes leucopenia and photosensitivity?

Answer 54

Sodium valproate

Question 55

What MRI finding is associated with temporal lobe epilepsy?

Answer 55

Hippocampal sclerosis

Question 56

What is the most common form of partial seizure?

Answer 56

Temporal lobe epilepsy