This boy likely suffers from tonic-clonic seizures (seen in the video) as well as absence seizures (short periods of inattention with a blank stare). Valproic acid is a first-line choice for tonic-clonic seizures and is also effective for absence seizures, so it would be the best initial choice of therapy.
Valproic acid can be used for partial seizures and generalized seizures, as well as in the treatment of migraines. It functions by increasing the refractory period of voltage gated sodium channels and inhibiting thalamic T-type calcium channels. Patients on valproic acid must have LFTs monitored because hepatotoxicity due to accumulation of toxic metabolites can occur. Other side effects include teratogenicity and pancreatitis.
Wilden and Cohen-Gadol discuss initial evaluation of first, nonfebrile seizures. Although much of the diagnostic workup depends on the patient history, head CT, serum glucose and sodium levels, pregnancy tests, lumbar puncture in immunocompromised patients, and EEG within 24-48 hours of the seizure are all recommended in the diagnostic workup.
Penovich et al. review the three main therapeutic options for absence seizures, concluding that ethosuximide most likely remains the front-line drug of choice. Valproic acid and lamotrigine are also effective although not to the same degree as ethosuximide. The authors additionally note limitations to current evidence in that many drugs have not been studied in large comparative trials.
Video V shows a patient undergoing a tonic-clonic seizure in an epilepsy monitoring unit. Note the alternation of stiffening and movement.
Answer 1: Gabapentin is useful in treatment of partial simple and complex seizures, as well as tonic-clonic, but it is not the first-line choice for tonic-clonic seizures and does not have effectiveness with absence seizures.
Answer 3: Phenytoin is a first-line choice for tonic-clonic seizures as well as status epilepticus prophylaxis but does not treat absence seizures.
Answer 4: Ethosuximide is first-line in treatment of absence seizures but is not effective in other seizure types.
Answer 5: Lorazepam, a benzodiazepine, is first-line acute treatment for status epilepticus.
Wilden JA, Cohen-Gadol AA. Evaluation of first nonfebrile seizures. Am Fam Physician. 2012 Aug 15;86(4):334-40. Review. PubMed PMID: 22963022
PMID: 22963022 (Link to Abstract)
Penovich PE, Willmore LJ. Use of a new antiepileptic drug or an old one as first drug for treatment of absence epilepsy. Epilepsia. 2009 Sep;50 Suppl 8:37-41. doi: 10.1111/j.1528-1167.2009.02234.x. PubMed PMID: 19702732
PMID:19702732 (Link to Abstract)
USMLE World Step 1 QBank Question #249. Copyright © USMLEWorld, LLC 2012