HTML clipboard

INSTRUCTION

This patient is suspected to have seizures; ask her a few questions. The eye-witness (usually the spouse) of the suspected event isnext to the patient and you may ask him or her any relevant questions.

SALIENT FEATURES

Proceed as follows:· Ask the patient about aura, whether she bit her tongue, whether she was incon-tinent during the attack, any hallucinations (ddjavu phenomenon). Ask the patient about triggering factors (including television, disco strobes, hypo-glycaemia and alcoholingestion) and whether they are recurrent. Take a family history (about 30% of patients with epilepsy have a history of seizuresin relatives) and past history of head injury.· Confirm this by asking the eye-witness for a description of the seizures (note whether they were tonic-clonic), frothing at themouth, whether the patient was unconscious or incontinent, how long the whole 'episode' lasted and how long she wasunconscious after the attack, and whether there was any weakness after the attack (Todd's paralysis).

DIAGNOSIS

This patient has recent-onset generalized tonic-clonic epilepsy (lesion) which could be due to an intracranial tumour (aetiology). Thepatient will have to give up her job as a truck-driver as a consequence of this (functional status).

QUESTIONS

How would you investigate the patient?

· Full blood count, urea and electrolytes, blood glucose, liver function tests.· Chest radiography.· EEG.· CT scan.· Magnetic resonance imaging and telemetry.

Mention some metabolic abnormalities found in these patients.

Hypoglycaemia, hyponatraemia (e.g. syndrome of inappropriate antidiuretic hormone secretion, SIADH), hypocalcaemia, hepaticfailure, uraemia.

How would you classify seizures?

· Generalized seizures: generalized tonic-clonic seizures, petit mai and atypical absences, myoclonus, akinetic seizures. Petitmal describes only 3 Hz seizures, rather than clinically similar absence attacks which are partial seizures.· Partial or focal seizures (a partial seizure is epileptic activity confined to one area of cortex with a recognizable clinical pattern):simple partial seizures (no impair-ment of consciousness), complex partial seizures, partial seizures evolving to tonic-clonic.

ADVANCED-LEVEL QUESTIONS

What is jacksonian epilepsy?

It is a simple partial seizure which usually originates in one portion of the prefrontal motor cortex so that fits begin in one part of thebody (e.g. thumb) and then proceed to involve that side of the body and then the whole body. It suggests a space-occupying lesion.

What is rodd's paralysis?

Paresis of a limb or hemiplegia occurring after an epileptic attack, which may last up to 3 days.

How would you manage epilepsy?

· General advice: Avoid ladders, heights, unsupervised swimming and cycling for 2 years from the last episode.· Antiepileptic drugs: The first line drugs for epilepsy monotherapy remain carbamazepine and sodium valproate; phenytoin isnow less used, and although lamotrigine has a monotherapy licence its place has still to be defined. Several new 'add-on drugs'have been licensed in recent years including vigabatrin, gabapentin, lamotrigine, and topiramate. An overview of trials inpatients with refractory partial seizures suggests no major differences between these agents in either efficacy or tolerability(BMJ 1996; 313: 1169-74). Prolonged use of vigabatrin can result in severe visual field defects, prompting the development ofguidelines for monitoring vision (BMJ 1998; 317: 1322).· Vagal stimulation remains an experimental approach in seizure control (J Clin Neurophysiol 1997; 14: 358-68).· Advice about driving: In the UK, those who have had more than one seizure are unable to hold a driving licence unless theyhave been free from any form ofepileptic attack whilst awake for a period of one year before the issue of a licence; in the case of attacks whilst asleep, these attacksmust have occurred only during sleep over a period of 3 years and no awake attacks before the issue of a licence. Drivers of heavygoods vehicles and public service vehicles must have been free of epileptic attacks for at least the last 10 years and must not havetaken anticonvulsant medications during this 10-year period.

What do you understand by the term 'status epilepticus'?

It is a medical emergency in which seizures follow each other without recovery of consciousness.

What is the prognosis in epilepsy?

· Most individuals with newly diagnosed epilepsy enter prolonged remission from seizures and have an excellent prognosis, butseizures remain refractory in 20 30%.· Up to 75% of patients with refractory partial epilepsy show evidence of abnormalities on magnetic resonance imaging (J NeurolNeurosurg Psych 1995; 59:384 7), some of which are amenable to surgery.· Population based studies show that patients with epilepsy have an increased risk of sudden death compared with age and sexmatched controls (J Neurol Neurosurg Psych 1995; 58: 4624). Some of these deaths are related to epilepsy itself, for exampleas a consequence of accidents, but others are unexplained. This has been termed 'SUDEP' (sudden unexpected death inepilepsy) and is more common in refractory epilepsy (about 1 in 200 patients per year). Many of these deaths may be related tounwitnessed seizures, possibly associated with respir-atory arrest, cardiac arrest or neurologically mediated pulmonaryoedema; there-fore a proportion of these deaths can potentially be prevented by better control of seizures.Robert B. Todd (1809-1860), FRS, an Irish physician, graduated from Pembroke College, Oxford, and was Professor of Physiologyat King's College, London (J Neurol Neurosurg Psychiatry 1994; 57: 359). He was founder of King's College Hospital.J. Hughlings Jackson (1835-1911), an English neurologist, worked at the National Hospital, Queen Square, London.