Abstracts

Rationale: La Crosse Virus (LACV) is the most common neuroinvasive arboviral disease in children. Previous studies demonstrate a 10% risk of developing epilepsy after infection. Contemporary data on clinical presentation, management, and predictors of epilepsy outcomes are lacking. Methods: A retrospective analysis was performed of children (0-18yr) admitted to Nationwide Children’s Hospital from 1/2009-12/2018 diagnosed with LACV neuroinvasive disease (LACV-ND). LACV-ND diagnosis was defined as a compatible clinical illness and serum serologic detection of LACV in the absence of other infectious etiologies. Demographic, clinical, laboratory, electroencephalography (EEG), neuroimaging, and epilepsy outcome data were recorded. Severe disease was defined as the presence of clinical or electroencephalographic status epilepticus, SIADH, PICU admission, mechanical ventilation, parenteral/tube feeding, inpatient rehab, or intracranial pressure monitoring. A diagnosis of epilepsy was determined by review of neurology outpatient records after admission of LACV-ND. Patients with incomplete follow-up data were excluded. The presence of epileptiform discharges was determined by review of the EEG report from admission. Single variable and multivariate analyses were performed to determine factors predictive of epilepsy diagnosis at follow up. Results: 140 patients were identified with LACV-ND. 18 patients were excluded from this analysis due to incomplete follow-up data. Symptoms at presentation, spinal fluid abnormalities, EEG findings, and neuroimaging findings are shown in Table 1. Out of 122 patients, 11 (9%) were diagnosed with epilepsy in follow up. Four patients underwent epilepsy surgery evaluations. Two patients had surgery. No deaths were observed. On univariate analysis, patients with the following features during acute illness were more likely to be diagnosed with epilepsy at follow up: seizures at any point in the disease course (0.001), status epilepticus (p=0.004), anti-seizure medication (ASM) exposure (p=0.002), ASM prescribed on discharge (p=<0.001), severe disease (p=0.02) and epileptiform discharges (p=0.01). Imaging findings were not predictive of future epilepsy diagnosis. On multivariate analysis, epileptiform discharges was independently associated with a diagnosis of epilepsy (OR 9.99 [95% CI 1.68 59.30], p=0.011). Conclusions: Patients diagnosed with epilepsy in follow up after admission for LACV-ND were more likely to have had seizure, status epilepticus, severe disease, ASM, or epileptiform discharges on EEG. These clinical and EEG findings can serve as predictors for patients at risk of developing epilepsy after LACV-ND. Funding: We received an intramural grant of $10,000 for trainees. The grant is being used to acquire long term neurodevelopmental outcomes on patients with LACV-ND.