Epilepsy/seizures Flashcards
How common is it?
1 in 103 people. 600,000 taking antiepileptic medication
Who does it affect?
Most commonly starts in children or in people older than 60 (bimodal incidence). Epilepsy is much more common in people with a learning disability. Epilepsy is often misdiagnosed (20-31% of the time) (usually falsely told they have epilepsy).
What causes it?
About two thirds if people in the UK do not have an anatomically identifiable cause, this is described as idiopathic epilepsy and is the most common cause of epilepsy in younger people. Underlying this is thought to be complex developmental abnormalities in synaptic connections and neurotransmitter distribution and release. A genetic predisposition is involved in many people. About 30% of people with it have a first degree relative with it.
About a third do have an identifiable anatomical abnormality (this tends to be in the older age group. This is called symptomatic epilepsy. Caused by cerebral vascular disease, cerebral tumour, and post-traumatic-epilepsy. Less common identifiable causes include perinatal brain injury caused by foetal hypoxia or trauma; cortical or vascular malformation; cerebral abscess or tuberculoma; and surgery to the brain.
What risk factors are there?
FHx
Genetic conditions, e.g. childhood epilepsy syndromes, or neurocutaneous syndromes such as tuberculosis sclerosis or neurofibromatosis
Previous febrile seizures (2-7%)
Previous intracranial infections, brain trauma (esp. penetrating) or surgery
Comorbid conditions such as CVD or cerebral tumours.
How does it present?
Tonic: Impairment of consciousness and stiffening (trunk straight or flexed at waist)
Clonic: Jerking and impairment of consciousness
Typical absence seizures which begin in childhood: There is a harp onset and no residual symptoms. Normal activity is interrupted and the child stares for a few seconds. The eyelids may twitch and some very small jerking movements of the hands may occur. Lasts 5-10 seconds and usually less than 30. Can occur hundreds of times a day in children.
Myoclonic: Brief, shock-like contraction of the limbs, without the apparent impairment in consciousness
Atonic: Sudden brief attacks of loss of tone, associated with falls and LOC.
Specific features of focal seizures:
Focal motor: jerking movement, typically beginning in the face or one hand, and spreading to involve the limbs. May also present with apparent purposeful movements such as turning the head, eye movements, lip smacking and mouth movements, drooling, or rhythmic muscle contractions. Limb weakness may occur for several hours after the seizure.
Focal sensory: Include temporal lobe seizures that may cause sensory, autonomic, emotional, cognitive, or other changes
Secondary generalised seizures start with a focal seizure before spreading toc cause a generalised seizure.
Signs on examination?
Should perform a cardiac, neurological, mental state and development assessment if possible.
Investigations
Baseline tests for adults: FBC, U&Es, LFTs, glucose, and calcium. A 12-lead ECG. EEG.
Treatment
A prolonged seizure (more than 3 mins) or repeated seizure are treated with rectal (10mg) or I.v. diazepam or lorazepam.
For status epilepticus, rectal diazepam or buccal midazolam.
The drugs given to prevent an attack are specific for the type of seizure, but for tonic-clonic you can give Sodium-valproate, lamotrigine, carbamazepine, topiramate and phenytoin
Conditions that would present similarly
Syncope (caused by things such as postural changes),
cardiac arrhythmias
Panic attacks with hyperventilation
Non-epileptic attack disorders
In children between 6months and 5 years: night terrors, breath holding attacks, stereotyped behavioural phenomena
