Abstracts

Rationale: Early diagnosis of SCN1A-related epilepsy has significant implications on management. While Dravet Syndrome (DS) is a clinical diagnosis, confirming the genetic etiology can rule out DS mimics. DS might also have some phenotypic variability leading to uncertainty in diagnosis. Genetic testing allows for informed anti-seizure medication choices, appropriate counseling, access to resources, and eligibility for clinical trials. The goal of this project is to assess the time from first seizure to genetic testing, as well as the factors associated with the length of this time.


Methods: We performed a retrospective chart review of all patients with DS (based on modified Delphi diagnostic criteria) and confirmed SCN1A variants, seen at Boston Children’s Hospital between 2000 and 2023. Factors collected included clinical presentation and socioeconomic variables. These factors were analyzed for correlation with time lag between the first documented seizure and genetic testing.


Results: Of the 157 patients identified with SCN1A variants, 69 met inclusion criteria. Ages ranged from 2 to 49 years of age. Average time to genetic testing was 43 months (range -5 to 210 months). Clinical factors significantly correlated with time to testing were presence (36 months) vs. absence (93 months) of status epilepticus before 2 years of age (p-value=.0028) and patient age (Adjusted R²=.61, p-value=2.40E-15). Socioeconomic factors significantly correlated with time to testing were interpreter need (83 months) vs. no interpreter need (37 months) (p-value=.0030) and Medicaid-equivalent/safety-net insurance (76 months) vs. other insurance (30 months) (p-value=.0044). Interestingly, neither race nor social deprivation index was significantly correlated with delays in genetic testing in our population.


Conclusions: While we show that time to testing has decreased over time, there remain certain factors leading to delays in genetic testing. Patients with DS without an early presentation for status epilepticus, non-English speaking families, and families with Medicaid-equivalent insurance experienced a significantly longer time to genetic testing.

Considerations to address these factors include a lower threshold for genetic testing in any child presenting with seizures in the context of fever under the age of 6 months, high quality translation services, resources in different languages, and access to genetic counseling. Purposefully addressing these factors will be important for early diagnosis and subsequent management.


Funding: None