Abstracts

Rationale: LGI1 antibody encephalitis is a rare autoimmune limbic encephalitis which has been reported predominantly in adults. Faciobrachial dystonic seizures are characteristically seen in this condition and have been described only in adults so far.  Other seizure types have also been reported including generalized tonic-clonic, focal, myoclonic seizures, and drop attacks. We describe a case of a 7-year-old girl with LGI1 limbic encephalitis who had a very unique seizure type not described in literature. Methods: Retrospective review of the patient's file was conducted following signed informed consent from the parents. IRB approval from local IRB commitee was granted. Results: Our proband is a 7-year old girl who was previously healthy. The seizures are characterized as stereotypic movements of the upper extremities which arise independently from both right and left hemispheres of the brain associated with ipsilateral ictal electrographic changes. (Videos of the seizure along with EEGs are going to be presented.) In contrast to FBDS which are usually reported to be not associated with abnormal ictal changes, these focal seizures associated with stereotypic movements had a clear ipsilateral ictal EEG change. These movements could possibly be considered as automatisms. The presence of hyponatremia and abnormalities in the mesiotemporal region on MRI and PET scan could aid in diagnosis. Conclusions: This case is unique since it describes the electroclinical presentation of a child with LGI1 encephalitis. It highlights the importance of having a high index of suspicion for diagnosis in young children as well. Early diagnosis can lead to prompt and appropriate treatment with immunotherapy, and potential harmful treatments like pharmacological coma can be avoided.  Prognosis of this condition is usually good but some patients can have recurrence, mostly within first 6 months. Data on prognosis is lacking in children.   Funding: No funding