Clinical and Therapeutic Profile of Dravet Syndrome in Patients Followed at a Brazilian Pediatric Referral Center: Real-World Data from a Tertiary Service

Background: Dravet syndrome (DS) is a severe developmental and epileptic encephalopathy, and data from low- and middle-income countries remain scarce. We characterized the clinical, genetic, and therapeutic profiles of patients with DS at a Brazilian tertiary referral center. Methods: This retrospective cross-sectional study included 27 patients with clinically and genetically confirmed DS (pathogenic/likely pathogenic SCN1A variants). Outcomes were ≥6-month and ≥12-month seizure freedom and seizure control in the previous month, described by treatment exposure without inferential testing. Results: The median age at seizure onset was 4 months and at diagnosis 42 months; the median individual onset-to-diagnosis interval was 29 months (range, 4–283; n = 14). All patients received polytherapy; 51.9% used cannabidiol, 40.7% vagus nerve stimulation, and 7.4% fenfluramine. Only 2/20 patients (10.0%) achieved ≥6-month and 1/20 (5.0%) ≥ 12-month seizure freedom. All six patients seizure-free in the previous month were receiving valproate, a descriptive finding likely reflecting confounding by indication. Recorded comorbidities, mainly autism spectrum disorder (29.6%), were likely underestimated in the absence of systematic neurodevelopmental assessment. Conclusions: This Brazilian DS cohort showed marked diagnostic delay, high seizure burden, and limited access to DS-specific therapies. These findings support earlier genetic testing and broader access to recommended treatments and generate hypotheses for larger prospective studies.