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Epilepsy by itself cannot be a diagnosis; it is merely a symptom of a brain disorder. Once it
is confirmed that the patient’s attacks are epileptic seizures, all efforts should be made to
identify the aetiology. The age of onset, types of seizures, and EEG patterns may allow
identification of a genetic generalised epilepsy syndrome (e.g. juvenile myoclonic epilepsy,
JME). State of the art MRI scans, reviewed by a neuroradiologist, will be able to identify
epileptogenic lesions in about two-thirds of all cases9. In patients with adult onset epilepsy,
where no epileptogenic lesions can be identified on MRI scans of adequate quality,
consideration should be given to testing for autoimmune causes10. Immunotherapy may have
a role in the treatment of seizures in patients who test positive for antibodies to neuronal
surface antigens.

Review of the diagnosis is an ongoing process. The description of each type of event, and a
clinical impression as to whether they are epileptic or not, as well as the frequency of each
type, should be documented at each encounter. One should always be prepared to change the
diagnosis in the light of any new information that emerges. It helps to have a consistent
system of documentation, and to use this at each patient encounter. The ILAE’s multi-axial
diagnostic scheme is ideal for this purpose, notwithstanding the changes to diagnostic
categories introduced recently (see Figure 2 for examples).

Review of AEDs present and past

It goes without saying that, once the diagnosis has been made, one should ascertain that the
AED used is appropriate for the type of epilepsy. Sodium channel blocking drugs and GABA-
ergic drugs can worsen seizures in generalised epilepsies and tiagabine has been associated
with episodes of non-convulsive status epilepticus in patients with focal and generalised
epilepsies11. Idiosyncratic seizure exacerbations can rarely occur with all drugs.

Neurologists frequently ‘inherit’ patients with refractory epilepsy from colleagues, or have
patients referred for specialist opinion. In these situations, it can be difficult to ascertain the
details of previous drug therapy, which may require further correspondence with the GP.
Efforts made in this regard can often identify useful therapeutic options (e.g. a patient with
refractory focal epilepsy who has never taken lamotrigine). This is also important in
determining AEDs that may be associated with a high risk of severe adverse effects (e.g.
oxcarbazepine and eslicarbazepine are best avoided in a patient with a history of allergic rash
with carbamazepine).

Figure 2. Documentation of epilepsy diagnosis in the header of an outpatient clinic letter,
using the ILAE semiologic classification.