Background: Seronegative autoimmune encephalitis (SAE) in children is associated with cognitive deficits, particularly executive dysfunction. However, the relationship between cognitive impairment, disease severity, and lesion burden remains unclear. Identifying these associations could improve patient management and outcomes. This study characterizes neuropsychological symptoms in pediatric SAE and compares patients with and without formal neuropsychological assessments to determine factors influencing cognitive impairment. Methods: A retrospective review was conducted on 155 pediatric autoimmune encephalitis cases, including 80 with SAE. Eleven had neuropsychological evaluations. Statistical analyses assessed differences in age, disease severity, lesion characteristics, hospitalization, and treatment needs. Results: Executive dysfunction was present in 75% of SAE cases. Patients with neuropsychological evaluations were older (median: 8 vs. 3 years, p = 0.0115) and had more severe encephalitis at admission (p = 0.0391) and one year later (p = 0.0011). Lesion burden did not differ (p > 0.05), but patients with assessments had longer hospitalizations and required more intensive treatments (p < 0.005). Conclusions: Executive dysfunction in pediatric SAE is linked to disease severity rather than lesion burden. Systematic neuropsychological assessments should be integrated into patient care. Deeper phenotyping of cognitive profiles and identifying risk factors for poor prognosis will help personalize care in order to improve outcomes.

We conducted a retrospective cohort study in Ontario, Canada between December 1, 2020 and June 31, 2021 to compare the incidence of neurological events (hospitalization or emergency room visit) within six weeks of COVID-19 vaccination in Chinese, South Asian and Other ethnic groups. Compared to Others, the crude rates after the first dose for Bell’s palsy, ischemic stroke and intracerebral hemorrhage were lower in Chinese (34, 159 and 48 per 1,000,000 doses) and in South Asians (44, 148 and 32), but similar after adjusting for age, sex and vaccine type. Our findings should help encourage vaccination for all, irrespective of ethnicity.

While tension-type headache (TTH) is the most common primary headache disorder, its effect according to sex, race and ethnicity remains unclear. We investigated disparities in sex, racial and ethnic representation in TTH clinical trials with comparison to global disease burdens. In this cross-sectional analysis, TTH clinical trials had female overrepresentation and racial and ethnic minority underrepresentation, which may affect understanding of the impact of TTH on different populations and personalized treatment development. Trial enrollment that is diverse and reflective of global disease burdens is crucial for improving study generalizability, understanding of diverse clinical presentations, and ensuring healthcare equity.

Background: Medulloblastoma (MB), the most common malignant pediatric brain tumor, is often incurable upon recurrence, largely driven by treatment-resistant quiescent cells. While quiescent SHH MB populations have been identified, the mechanisms driving their chemoresistance remain unclear. Here, we investigate the role of the cell cycle inhibitor p57 in inducing quiescence and show that dexamethasone, widely used in MB management, promotes p57-mediated quiescence, potentially reducing treatment efficacy. Methods: To assess p57’s role, we introduced a TMP-inducible p57 construct into Ptch1+/- SHH MB cells and treated them with vincristine. We also treated Ptch1+/- SHH MB cells with dexamethasone and quantified p57 levels and cell cycle states using high-throughput immunofluorescence imaging. Results: In culture, nuclear p57 was enriched in Sox2+ and Nestin+ stem-like SHH MB cells relative to rapidly-cycling Atoh1+ cells. Stabilizing p57 with TMP increased G0-phase cells six-fold, exhibiting survival to vincristine doses that caused complete cell death in controls. Dexamethasone treatment increased nuclear p57 by 40% and G0-phase cells by 15% in Ptch1+/- cells, while doubling G0-phase cells in Ptch1+/-;Trp53-/- cells. Conclusions: These findings suggest dexamethasone promotes p57-mediated quiescence, potentially contributing to chemoresistance in SHH MB. This raises critical concerns about the use of dexamethasone in MB treatment, as it may inadvertently enhance tumor recurrence.

Advance consent could address many of the limitations traditional consenting methods pose to participation in acute stroke trials. We conducted a series of five focus groups with people with lived experience of stroke. Using an inductive thematic approach, two themes were developed: factors in favour of, and against, advance consent. Participants supported the idea of advance consent and highlighted trust, transparent communication and sufficient time as major factors that would positively affect their decision to provide advance consent. The results will be used to finalise a model of advance consent suitable for testing the feasibility in stroke prevention clinics.

Background: Infections are hypothesized to trigger certain autoimmune diseases; however, there is a lack of epidemiologic data surrounding pediatric neuro-autoimmune disorders during the COVID-19 pandemic. Our retrospective study assessed the incidence of pre-defined autoimmune disorders at the Children’s Hospital of Eastern Ontario from October 2017-June 2024. Methods: Inpatient/outpatient charts were queried to identify subjects with neuro-autoimmune disorders or type 1 diabetes (T1D) as a non-neurological autoimmune comparison group. Monthly incidences were compared between three COVID-19 pandemic restriction periods: the pre-restrictions (October 2017-March 2020), intra-restrictions (April 2020-June 2022), and post-restrictions periods (July 2022-June 2024). Poisson regression models were fit to the incidence data. To evaluate incidence of specific neuro-autoimmune disorders, crude monthly incidences of six diagnosis categories were compared: ‘Guillain-Barré syndrome’, ‘anti-NMDAR encephalitis’, ‘juvenile dermatomyositis’, ‘multiple sclerosis (MS)’, ‘acute demyelinating disorders’, and ‘other’. Results: Incidence of neuro-autoimmune disorders, but not T1D, decreased during the intra-restrictions period compared to the pre-restrictions period (IRR=0.57, 95% CI: 0.33-0.95, P<0.05). Grouping neuro-autoimmune subjects by diagnosis category showed a trend towards decreased incidence during the intra-restrictions versus pre-restrictions periods for all groups except MS. Conclusions: Incidence of certain neuro-autoimmune disorders, but not MS and T1D, decreased during pandemic restrictions, which may be due to reduced transmission of key infectious triggers.

Background: Schizencephaly is a congenital brain malformation involving a cleft in the cerebral hemisphere lined with abnormal gray matter with an estimated incidence of 1.5 per 100,000 live births. Methods: This study aims to characterize the radiological, etiological, and clinical features of schizencephaly, identifying factors predictive of patient outcomes. A retrospective cohort of 94 individuals, both adult and pediatric, was analyzed across four tertiary care centers. A neuroradiologist systematically reviewed imaging, while charts were reviewed for clinical features. Results: Several perinatal risk factors were identified, including young maternal age and prenatal infections. However, genetic testing yielded only one pathogenic COL4A1 mutation. MRI findings showed frequent additional malformations, including those in the pituitary, corpus callosum, and fornix. Clinical characteristics included neurodevelopmental delay (71.6%), seizures (50.0%), and motor impairments (53.3%). Outcomes were heterogeneous, with bilateral and open-lip clefts associated with more severe developmental delays, while seizure rates were comparable across subtypes. Conclusions: The complexity of schizencephaly is highlighted in the largest cohort reported with high rates of seizures, neurodevelopmental delays, and motor impairments, but outcomes varied widely based on imaging features, underscoring the importance of individualized management. The low yield of genetic findings emphasizes prenatal environmental risk factors as etiological contributors.