Abstracts

Seizure Description and Clinical Features of Immune Mediated Seizures in Children

Abstract number : 2.118
Submission category : 4. Clinical Epilepsy / 4B. Clinical Diagnosis
Year : 2022
Submission ID : 2204558
Source : www.aesnet.org
Presentation date : 12/4/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:25 AM

Authors :
Mohammed Alqahtani, MD – Hospital for Sick Children (SickKids); Cristina Go, MD – Staff physician, Neurology, SickKids; Paula Melendres, EEG technician – Neurophysiologist, Neurology, The Hospital for Sick Children (SickKids); Ann Yeh, MD – Staff physician, Neurology, The Hospital for Sick Children (SickKids)

Rationale: Immune mediated epilepsies are some of the common etiologies for new onset refractory status epilepticus (Hirsch et al, 2018). It also attributes to a significant proportion of patients with treatment resistant epilepsy (Tecellioglu et al, 2018). It is important to recognize immune mediated seizures early in the disease process, as evidence suggests this subset of epilepsy patients respond to immune modulatory therapies (IMTs) more favorably compared to ASMs, and that delays in therapy constitute a lost opportunity for better response to IMTs (Dubey et al, 2016). The literature lacks data driven criteria for picking up patients who might benefit from initiation of IMTs at an early stage of their disease process.

Objective: To identify early clinical features of immune mediated seizures in a cohort of children with epilepsy and known autoimmune encephalitis.

Methods: We performed a retrospective chart review of consecutive neuroinflammatory patients with evidence for probable immune mediated seizures based on their response to therapy, positive biopsy, positive autoantibodies, positive MRI, or suggestive LP findings who were treated at the Hospital for Sick Children, Toronto Canada, in the period from January 2012 to December 2018. REB approval was obtained and descriptive data analysis was performed using Microsoft Excel.

Results: We have identified 35 patients who fulfilled our inclusion criteria with complete charts. In 97%, the first unprovoked seizure was the presenting symptom, and 47.5% of them had status epilepticus in the first 48 hours of seizure onset.  When assessing the seizure itself, it was focal onset in 91% and was motor in 71%, and non-motor in 6%, while 23% had both motor and nonmotor seizures. 91% of them had at least one associated symptom either as a prodrome, or a symptom that developed within 48 hours of seizure onset. When assessing delays in treatment, the median delay in introduction of IMTs was 12 days, but with a mean of 142 days. IMTs were the most effective therapy in 75% of the cohort.

Conclusions: Our data indicate that there are clinical features that can be used in the first 48 hours of seizure onset to identify patients with possible immune mediated seizures. We propose an algorithm to identify and treat patients with new onset seizures with high likelihood of having immune mediated seizures, to be utilized as a guide to start IMTs after ruling out infectious and vascular causes (Figure 1).

Funding: No funding was received for this project.
Clinical Epilepsy