New Onset Epilepsia Partialis Continua Presenting as Complex Visual Hallucinations associated with Voltage-Gated Potassium Channel Antibody

Abstract

A 54-year old female with past medical history significant for rheumatoid arthritis on immunosuppressant therapy presented with episodes of left-sided shaking and left gaze deviation with decreased level of consciousness. A preceding one-month history of complex visual hallucinations was subsequently elicited. Brain Computed Tomography (CT) perfusion and Magnetic Resonance Imaging (MRI) showed changes in the right parieto-occipital lobe that were consistent with possible seizure activity. Electroencephalogram (EEG) subsequently confirmed electrographic seizures originating from the right occipital region during active hallucinations. Patient’s right occipital lobe epilepsia partialis continua was refractory to as many as 5 concomitantly administered antiepileptic medications. Patient was subsequently treated for presumed autoimmune encephalitis, but demonstrated no response to IV steroids, and showed only marginal improvement to IVIG infusion. Serum testing ultimately showed a high titer of voltage-gated potassium channel (VGKC) antibodies; and after a 5-day course of plasma exchange the patient finally achieved better control of her partial seizures, requiring long-term therapy with multiple antiepileptic medications for seizure control.

[N A J Med Sci. 2018;11(1):28-33.   DOI:  10.7156/najms.2018.110128]