Immunotherapy-responsive epilepsy
Clinical cases: Neurology
Background
A 74-year-old man presents with subacute confusion and abnormal movements. His episodes are brief (2–10 seconds), affect the right side of his face and right arm (occasional leg involvement), and occur up to 30 times per hour. The episodes continue despite four antiepileptic medications and are consequently thought to be psychiatric.
An autoimmune epilepsy evaluation is sent to Mayo Clinic Laboratories. The VGKC antibody value was 2.62 nmol/L (normal ≤ 0.02), and LGI1 antibody was positive by cell-binding assay. The patient is diagnosed with autoimmune epilepsy associated with VGKC autoantibodies (LGI1 subtype). The episodes represent what is termed faciobrachial dystonic seizures. Immunotherapy remedies the confusion and seizures.
Teaching points
- Autoimmune epilepsy is an expanding field.
- Autoimmune neurologic disorders can be misdiagnosed as psychiatric.
- Patients not responding to antiepileptic drugs may respond to immunotherapy.
Key testing
EPC2 | Epilepsy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
- Turnaround time: 10 days
EPS2 | Epilepsy, Autoimmune/Paraneoplastic Evaluation, Serum
- Turnaround time: 7 days
See how our suite of testing can be useful in diagnosing immunotherapy-responsive epilepsy.
