Abstracts

Rationale: Limbic encephalitis is typically a paraneoplastic syndrome with a poor prognosis. Voltage gated potassium channel antibody (VGKC-Ab) can occur with or without cancer association and manifest as neuromyotonia, Morvan’s syndrome, limbic encephalitis or seizures. Antibodies to VGKC are present in 6% of patients with typical long-standing epilepsy, but it is unknown how many cases of new onset adult epilepsy might be due to VGKC-Ab. Methods: To describe and discuss a case of a patient with positive VGKC-Ab presenting with a first generalized convulsive event 1 week after a motor vehicle accident. Results: During four days of EMU admission the patient had 50 electrographic seizures coming from both temporal lobes with minimal or no clinical correlation. Despite a proper antiepileptic regimen and resolution of clinical episodes, the patient developed episodes of forgetfulness, inattentiveness and fatigue which prompted further investigations. A repeat brain MRI did not show a signal change in the medial structures including temporal lobes. Neuropsychological testing confirmed significant global impairment. Further diagnostic investigations revealed VGKC-Ab suggesting a possibility of antibody-related epilepsy. Conclusions: This unique case of antibody-related epilepsy in short temporal relation with a head trauma raises the question of posttraumatic development of antibody-related epilepsy. A case of myokymia with positive VGKC-Ab after a medial nerve injury has been reported. Unexplained cases of memory loss, confusion and seizures, even if posttraumatic, should prompt further investigation of antibody titers even if a brain MRI is not indicative of typical limbic encephalitis pattern.