Seizure Semiology, EEG, and Imaging Findings in Epilepsy Secondary to Mitochondrial Disease

Background: Identification of an underlying mitochondrial disorder can be challenging due to the significant phenotypic variability between and within specific disorders. Epilepsy can be a presenting symptom with several mitochondrial disorders. In this study, we evaluated clinical, electrophysiologic, and imaging features in patients with epilepsy and mitochondrial disorders to identify common features, which could aid in earlier identification of a mitochondrial etiology.Methods: This is a retrospective case series from January 2011 to December 2019 at a tertiary referral center of patients with epilepsy and a genetically confirmed diagnosis of a mitochondrial disorder. A total of 164 patients were reviewed with 20 patients fulfilling inclusion criteria.Results: A total of 20 patients (14 females, 6 males) aged 0.5–61 years with epilepsy and genetically confirmed mitochondrial disorders were identified. Status epilepticus occurred in 15 patients, with focal status epilepticus in 13 patients, including 9 patients with visual features. Abnormalities over the posterior cerebral regions were seen in 66% of ictal recordings and 44% of imaging studies. All the patients were on nutraceutical supplementation with no significant change in disease progression seen. At last follow-up, eight patients were deceased and the remainder had moderate-to-severe disability.Discussion: In this series of patients with epilepsy and mitochondrial disorders, we found increased propensity for seizures arising from the posterior cerebral regions. Over time, electroencephalogram (EEG) and imaging abnormalities increasingly occurred over the posterior cerebral regions. Focal seizures and focal status epilepticus with visual symptoms were common. Additional study is needed on nutraceutical supplementation in mitochondrial disorders.

RHOBTB2 gene associated epilepsy and paroxysmal movement disorder: two cases report and literature review

Background RHOBTB2 gene is associated with developmental and epileptic encephalopathy-64(DEE-64), which is characterized by epilepsy, developmental delay, microcephaly, unspecific facial dysmorphism, and paroxysmal movement disorders. Most previous studies showed that the phenotypes of RHOBTB2 gene include developmental and epileptic encephalopathy(DEE) and DEE with paroxysmal movement disorders. Only one study showed that patient with RHOBTB2 variant had paroxysmal movement disorders with no epilepsy. Case presentations Two cases with RHOBTB2 variants are presented here: Case one was diagnosed as DEE, he had recurrent afebrile focal status epilepticus and paroxysmal extrapyramidal symptoms in infancy. Interictal electroencephalogram (EEG) showed focal discharges. Brain magnetic resonance imaging (MRI) showed cortical dysplasia. Epilepsy of case one was refractory. Nevertheless, case two only showed paroxysmal movement disorders alone in adolescence. Video EEG showed focal discharges during an interictal dystonic episode and he brain MRI was normal. Conclusion The phenotypes of RHOBTB2 gene include DEE, paroxysmal movement disorders, and DEE with paroxysmal movement disorders. RHOBTB2 can be one of the pathogenic genes of paroxysmal movement disorders.

Cognitive Status Epilepticus: Two Case Reports

Cognitive status epilepticus is an uncommon form of focal status epilepticus presenting with a dysfunction of language, thinking or associated higher cortical functions. The absence of ictal manifestations can be misleading and delay a prompt diagnosis. Here we present two patients; one with amnesic and one with aphasic status epilepticus. Through these cases, we aim to highlight the value of EEG performance early in the diagnostic work-up and early antiepileptic drug initiation in cases where an epileptic disorder cannot be excluded.

Ping-pong gaze in a refractory focal status epilepticus

An 83-year-old woman presented to emergency department with fever, low level of consciousness and right deviation in the conjugate gaze. Neurological examination revealed a spontaneous, slow, horizontal and continuous conjugate eye deviation alternating every 2 to 3 seconds. An electroencephalogram revealed periodic paroxysmal activity with a frequency of 2-3 Hz in left frontal hemispheric. Neuroimaging didn’t show pathological findings. Polymorphonuclear leukocytes were observed in CSF without evidence of microorganisms. Antiepileptic therapy was started without improvement. Finally, the patient died because of refractory focal status. Ping Pong Gaze (PPG) is a slow and rhythmical horizontal abnormal eye movement with a fixed frequency that is observed in comatose states and indicates diffuse structural brain lesions with preserved brainstem functions. PPG presence is an indicator of bad prognosis. We describe a PPG case with a synchronous eye movement with the electroencephalogram activity. Keywords: Ping-pong gaze; status epilepticus; electroencephalography; epilepsy; seizure.

Continuous Visual Focal Status Epilepticus as the Primary Presentation of NMDA-R and GAD65-R Autoimmune Epilepsy

Epilepsia partialis continua (EPC) has changed in its clinical and pathophysiological definition throughout time. Several etiologies have been described in addition to classic causes of EPC. The following case depicts a young woman who had a peculiar onset of epilepsy with a continuous visual aura becoming a form of chronic recurrent and non-progressive EPC. The patient was initially misdiagnosed as a non-neurological entity (assumed psychiatric in origin), but finally, an immune-mediated epilepsy was diagnosed, and EEG showed focal status epilepticus during evolution. Once the diagnosis was achieved and immune treatment was established, the patient is seizure free. Early identification of an immune basis in patients with epilepsy is important because immunotherapy can reverse the epileptogenic process and reduce the risk of chronic epilepsy. To date, this is the only case reported with EPC manifesting as a continuous visual aura associated with antiglutamic acid decarboxylase 65 (anti-GAD65) and anti-N-methyl-d-aspartate (anti-NMDA) antibodies.