This patient most likely has a focal epilepsy syndrome. It is crucial to ask a patient being evaluated for a first seizure about previous more subtle events, such as auras, changes in awareness, and periods of inattention, that may indicate the presence of an as yet unrecognized epilepsy syndrome. The difficult-to-describe sensation of déjà vu that occurred just before this patient's seizure most likely represents an epileptic aura, which is actually a simple partial seizure. The fact that she had the same sensation previously over the past several years suggests that she has had partial seizures before. The features of her current seizure (unilateral shaking and a subjective aura before the onset of convulsion) suggest progression to a secondarily generalized seizure typical of focal epilepsy, although these features are not always present in secondarily generalized seizures.

Alcohol withdrawal is among the many metabolic stressors that can lead to a provoked seizure. Alcohol withdrawal seizures typically occur with other symptoms of withdrawal (behavioral changes and autonomic symptoms) but can sometimes occur in isolation before other withdrawal symptoms. This type of seizure typically does not have the focal features described in this patient, whose previous, recurrent seizures support a diagnosis of epilepsy. In patients with epilepsy, similar triggers, particularly alcohol ingestion and sleep deprivation (as in this patient), can precipitate a seizure or a more serious seizure. However, these seizures are not considered “provoked”; this term is reserved for isolated events in patients without epilepsy.

Distinguishing between focal and generalized epilepsy syndromes may not be possible if a patient has convulsions only. This patient's seizure was preceded by an aura, which is associated with focal epilepsy. The age of onset in this patient (between 30 and 40 years) is also atypical for generalized epilepsy, which usually begins in adolescence or early adulthood.

A posttraumatic seizure can occur within a week of significant head trauma. This patient had head trauma without loss of consciousness 1 month before onset of her first recognized seizure. Her mild head trauma most likely is not related to her convulsive seizure or the diagnosis of epilepsy, particularly because her auras began before she hit her head.