An acute symptomatic seizure is triggered by a recent or ongoing
neurologic insult such as infection, trauma, stroke, or metabolic
disturbance. Examples include seizures in the setting of encephalitis,
head injury, or intoxication. Evaluation of an acute symptomatic
seizure, even if the seizure is brief, is often emergent and guided
by the overall clinical picture. If the history and examination
suggest that a seizure is acutely provoked, then tests typically
include blood tests to diagnose infection or metabolic disturbance,
toxicologic screening, and head computerized tomography (CT) if
trauma or hemorrhage is suspected. Lumbar puncture may also be warranted
if there is suspicion that an intracranial infection caused the
seizure. If after the seizure the patient has not recovered fully,
has persistent focal neurologic deficits, or has not regained baseline
consciousness, testing may be followed by magnetic resonance imaging
(MRI) to evaluate for a structural abnormality, or electroencephalography
(EEG) to evaluate for nonconvulsive seizures (see Chapter 561).