Poster Number: 2.217

Rationale: New onset focal seizures in children are common in clinical practice. Improved understanding of their aetiology, neurodevelopmental associations, and treatment outcomes can lead to optimal diagnosis and treatment.

Methods: Data were gathered from The Children's Hospital at Westmead admissions for patients aged one month to 18 years who presented with new-onset focal seizures between 2018 and 2022 (n = 65). Clinical associations between aetiologies and comorbidities/treatment outcomes were investigated using non-parametric tests and hierarchical cluster analysis. Logistic regression was performed to identify predictors of drug resistance and therapeutic responsiveness of anti-seizure medications. The analysis of medication effectiveness was supplemented by a network graph of medication use.


Results: The most common aetiologies were self-limited childhood focal epilepsies (n = 14, 22%), structural (n = 12, 19%), inflammatory (n = 7, 11%) and unknown (n = 25, 39%). Table 1 shows that children with known aetiology were associated with explosive-onset seizures (p = 0.006), focal neurological abnormalities (p = 0.01), abnormal neuroimaging findings (p < 0.001) and drug resistance (p = 0.01). Hierarchical cluster analysis grouped the patients into six clusters with similar aetiology (Figure 1a). As shown in Figure 1b, explosive onset of seizures is predominant in Clusters 3 (“structural”), 5 (“inflammatory/metabolic”), 6 (“inflammatory/genetic”), and abnormal neuroimaging findings and neurological deficits are relatively prevalent in Cluster 3. Multivariable logistic regression showed the risk of drug resistance increased with presence of known genetic (OR 26.2; 95% CI 2.33 – 484.4), structural (OR 8.20; 95% CI 1.20 – 77.8) and inflammatory (OR 30.0; 95% CI 2.71 – 544.6) aetiologies, as well as, neurodevelopmental comorbidities (OR 8.21; 95% CI 1.53 – 71.6). After adjustment for these risk factors, first-line anti-seizure medications that were the strongest predictors for therapeutic responsiveness were carbamazepine (OR 11.9; 95% CI 3.03 – 47.7) followed by levetiracetam (OR 4.07; 95% CI 1.11 – 16.9).




Conclusions: Our study highlights the common occurrence of secondary aetiology in new onset focal seizures, which has significant treatment implications. A significant proportion of this group have neurodevelopmental comorbidities and drug resistance, emphasizing the need for ongoing monitoring. New onset seizures with unknown causes require further investigation for improved interventions.


Funding: This work was supported by scholarship from NHMRC EL1 investigator grant 2017279.