What are the management options for Epilepsia Partialis Continua (EPC)?

Management of Epilepsia Partialis Continua (EPC)

The management of Epilepsia Partialis Continua requires a stepwise approach starting with antiseizure medications, followed by immunotherapy in resistant cases, and considering surgical options for surgically amenable cases. 1

First-Line Treatment

• Begin with benzodiazepines as the initial treatment for EPC, similar to the approach for status epilepticus 2, 3
• Establish intravenous access for medication administration; if not available, consider rectal diazepam or intramuscular phenobarbital 3
• Ensure proper airway management, oxygenation, and place patient in recovery position to prevent aspiration 3
• Immediately check blood glucose to rule out hypoglycemia, which can be a common cause of EPC, especially in cases of diabetic non-ketotic hyperosmolar state 3, 4

Second-Line Treatment

• If seizures persist after benzodiazepines, administer one of the following second-line agents:
  • Fosphenytoin: 18-20 PE/kg IV at a maximum rate of 150 PE/min 5, 6
  • Valproate: 20-30 mg/kg IV at a maximum rate of 40 mg/min 5, 6
  • Levetiracetam: 30-50 mg/kg IV at 100 mg/min 5, 6
• The ESETT trial showed similar efficacy (45-47%) for all three agents in terminating status epilepticus at 60 minutes 5, 6
• Consider valproate for patients with cardiac issues due to lower risk of hypotension (1.6% vs 3.2% with fosphenytoin) 6

Refractory EPC Management

• For EPC that fails to respond to first and second-line treatments, consider:
  • Phenobarbital: 10-20 mg/kg IV; may repeat 5-10 mg/kg at 10 minutes 5
  • Propofol: 2 mg/kg bolus; may repeat in 3-5 minutes; maintenance infusion of 5 mg/kg/h (requires respiratory support) 5
• Newer agents showing promise for refractory EPC:
  • Perampanel has shown dramatic improvement in pediatric EPC cases, with sustained efficacy after 5 months of follow-up 7
  • Lacosamide may be useful in treating status epilepticus and needs more study 5

Advanced Treatment Options

• For drug-resistant EPC, consider immunotherapy trials, especially when autoimmune etiology is suspected 1
• Neocortical electrical stimulation has shown >90% reduction in seizures in drug-resistant EPC cases where the focus was near eloquent motor cortex (continuous stimulation at 60-130 Hz, 2-3 mA) 8
• Epilepsy surgery is effective in surgically amenable cases, such as hemispherotomy for Rasmussen encephalitis or lesionectomy for focal cortical dysplasia 1, 7

Diagnostic Workup

• Perform electroencephalography (EEG) to detect subtle or nonconvulsive status epilepticus, especially in patients with persistent altered consciousness 2, 1
• Obtain brain MRI to identify structural abnormalities that may be causing EPC 1
• Consider PET scan of the brain for further evaluation 1
• Test for autoimmune antibodies, infections, and metabolic disorders 1
• Genetic testing may be warranted in certain cases 1

Etiology-Specific Considerations

• Diabetic non-ketotic hyperosmolar state is a common cause of EPC and requires prompt correction of metabolic abnormalities 4
• Other etiologies include structural brain abnormalities, infections, inflammatory conditions, traumatic brain injury, and vascular causes 1
• In a study of 17 EPC patients, 10 had diabetic non-ketotic hyperosmolar state, highlighting the importance of metabolic evaluation 4

Common Pitfalls to Avoid

• Delaying treatment of EPC, as prolonged seizures can lead to long-lasting deficits in limb function 8
• Failing to identify and treat the underlying cause, which is essential for good outcomes 4
• Not recognizing non-convulsive status epilepticus, which may require EEG monitoring 6
• Overlooking the need for continuous EEG monitoring in patients with altered mental status after apparent seizure control 2

Long-term Management

• For long-term control, consider carbamazepine which has shown the highest 12-month remission rate (85.55%) compared to topiramate (69.38%), lamotrigine (70.79%), levetiracetam (72.54%), and valproate (73.33%) in partial epilepsy 9
• Oxcarbazepine and levetiracetam also show good retention rates for long-term management 9
• Monitor for common adverse effects including memory problems (8.09%), rashes (7.76%), abnormal hepatic function (6.24%), and drowsiness (6.24%) 9