A 23-year-old man is brought to the emergency department by ambulance for a seizure. According to a witness, he fell on the sidewalk while leaving a pub and had rhythmic movements of the extremities for about 2 minutes. He has no prior history of seizures. In the emergency department, the patient is lethargic and confused but follows simple commands. His temperature is 37.3° C (99.2° F), blood pressure is 122/70 mm Hg, and pulse is 97/min. The pupils are equal and reactive to light. He moves all his extremities, and the deep-tendon reflexes are symmetric. Complete blood count, serum electrolytes, electrocardiogram, and cervical spine imaging are normal. A urine toxicology screen is ordered. What is the most appropriate next step in management of this patient?

Question

A 23-year-old man is brought to the emergency department by ambulance for a seizure.  According to a witness, he fell on the sidewalk while leaving a pub and had rhythmic movements of the extremities for about 2 minutes.  He has no prior history of seizures.  In the emergency department, the patient is lethargic and confused but follows simple commands.  His temperature is 37.3° C (99.2° F), blood pressure is 122/70 mm Hg, and pulse is 97/min.  The pupils are equal and reactive to light.  He moves all his extremities, and the deep-tendon reflexes are symmetric.  Complete blood count, serum electrolytes, electrocardiogram, and cervical spine imaging are normal.  A urine toxicology screen is ordered.  What is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

This patient presents with an apparent unprovoked first seizure. Neuroimaging with computed tomography (CT) or magnetic resonance imaging (MRI) should be performed in all patients with an apparent unprovoked seizure as part of neurodiagnostic evaluation. Given this patient's history of fall and possible head trauma, brain CT without contrast should be the initial imaging study in the emergency department. It can be performed relatively quickly even in an unstable patient and can exclude acute life-threatening neurologic problems (eg, intracranial or subarachnoid bleed) that might require urgent intervention. In nonemergency or elective situations, MRI is the neuroimaging modality of choice. It is more sensitive than CT in identifying most structural causes of epilepsy, including temporal sclerosis, cortical dysplasia, vascular malformations, traumatic brain injury, cerebral infarction, central nervous system tumors, and infections. (Choice A) CT scan of the brain with contrast is useful in identifying structural abnormality or mass lesions (eg, primary or metastatic cancer, abscess, infarct). However, it is less sensitive, and MRI is the preferred modality in nonemergency situations. In addition, CT with contrast is not helpful for identifying intracranial hemorrhage. (Choice C) Electroencephalography (EEG) is a useful diagnostic study in patients with unprovoked first seizure. It helps to stratify patient risk in the need for maintenance antiepileptic agents. However, it is important to rule out any structural brain lesions (eg, mass, intracranial bleeding) with neuroimaging prior to EEG. (Choice D) This patient has no history of epilepsy, had a self-limiting seizure, and has no evidence of recurrent or frequent seizure activity. Such patients do not require administration of benzodiazepines or antiepileptic drugs unless there is clinical evidence of recurrent seizure activity. (Choice E) A lumbar puncture should be performed if the patient exhibits symptoms or signs suggestive of acute central nervous system infection (eg, fever, nuchal rigidity, focal signs). Moreover, a lumbar puncture should be performed only after a space-occupying lesion has been excluded by neuroimaging studies. Educational objective: Computed tomography (CT) scan of the brain without contrast is the initial imaging study of choice in patients with unprovoked first seizure to exclude acute neurologic problems (eg, intracranial or subarachnoid bleed) that might require urgent intervention. Magnetic resonance imaging is more sensitive than CT in identifying most structural causes of epilepsy and is the neuroimaging modality of choice in elective situations. References: Reassessment of neuroimaging in the emergency patient presenting with seizure (an evidence-based review): report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. (http://www.ncbi.nlm.nih.gov/pubmed/17967993)

A 23-Year-Old Man Is Brought to the Emergency Department by Ambulance