Genetic or Autoimmune: POLG-Related Epilepsy Initially Treated as an Autoimmune Encephalitis, a Case Report

Area of Science:

• Neurology
• Genetics
• Immunology

Background:

• Autoimmune encephalitis (AE) is a common cause of fulminant epilepsy.
• Increasing recognition of antibody-mediated AE leads to more patients being diagnosed with antibody-negative AE.

Observation:

• A young man with new-onset refractory seizures was treated for presumed autoimmune epilepsy.
• He developed valproic acid-induced hepatotoxicity requiring liver transplantation.

Findings:

• The patient was later diagnosed with a POLG mutation.
• POLG mutations can present with symptoms mimicking autoimmune epilepsy.

Implications:

• It is crucial to consider genetic etiologies, such as POLG mutations, in cases of new-onset refractory epilepsy.
• Broadening the differential diagnosis beyond autoimmune processes can prevent unnecessary immunosuppression and iatrogenic toxicity.