Clinical Evaluation and Diagnosis
Core concepts
The first task is classification: focal vs. generalized vs. unknown onset, and motor vs. nonmotor. Use the ILAE framework: seizure type, epilepsy type, epilepsy syndrome. A detailed history from the patient and witnesses is the highest-yield diagnostic tool. Key features: aura, loss of awareness, automatisms (oroalimentary, manual), lateralizing signs (head version, dystonic posturing, Todd paresis), postictal confusion, tongue biting (lateral), urinary incontinence, and duration.
Mimics and traps
- Syncope - provocation by standing, pallor, brief myoclonic jerks, rapid recovery; convulsive syncope can mimic a seizure.
- Psychogenic nonepileptic seizures (PNES) - longer duration, eyes closed, asynchronous movements, pelvic thrusting, no postictal confusion; but no single feature is definitive.
- TIA, migraine, sleep disorders, movement disorders, and parasomnias are common mimics.
- First seizure workup: history, exam, labs (glucose, electrolytes, tox screen), EEG, and brain MRI. Routine labs rarely identify the cause; the EEG and MRI drive management.
Worked example
A 24-year-old has episodes of déjà vu, lip smacking, and postictal confusion lasting minutes. This is a focal impaired awareness seizure, likely temporal lobe. Next steps: MRI (look for hippocampal sclerosis) and EEG. Do not label as generalized.
Rule of thumb
If the description includes provocation, pallor, and rapid recovery, think syncope. If it includes stereotyped automatisms and postictal confusion, think focal seizure.