Late-onset Rasmussen Syndrome: Clinical and Surgical Outcomes
Abstract number :
2.214
Submission category :
4. Clinical Epilepsy / 4B. Clinical Diagnosis
Year :
2024
Submission ID :
974
Source :
www.aesnet.org
Presentation date :
12/8/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Gloria Ortiz Guerrero, MD – Mayo Clinic, Rochester, MN, USA
Jeffrey Britton, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Divyanshu Dubey, MBBS – Department of Neurology, Mayo Clinic, Rochester MN USA
Kelsey Smith, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Rationale: Late-onset Rasmussen syndrome (RS) is rare, and the literature describing this entity is sparse. Here, we describe the clinical and surgical outcomes in patients with late-onset RS.
Methods: Patients diagnosed with RS based on Bien et al. (2005) criteria1 evaluated between 1/1/2001 and 6/1/2023 at Mayo Clinic were retrospectively identified. Patients who experienced seizure onset after 12 years of age were classified as late-onset. Data included demographic information, types of neurological deficits at onset and throughout the course of the disease, responses to immunotherapy and antiseizure medications, surgical epilepsy procedures, and outcome. Clinical factors were compared between patients with late-onset and early-onset using a chi-squared test.
Results: A total of fifty patients with RS were identified, including 17 (34%) in the late-onset group, of which ten were females (58.8%). In this late-onset group, 13 patients had seizures as the initial symptom onset. Motor deficits were the most common neurological symptoms associated with this condition (n=14). Focal to bilateral tonic-clonic seizures were the most prevalent seizure type (n=11). Only six patients had epilepsia partialis continua. Only one patient underwent surgical resection with a left frontal lobectomy with Engel class IV at the last follow up appointment. Three patients underwent neuromodulation; one had implanted both VNS (turned off) and DBS (4 leads targeting bilateral ANT, left CM, and left pulvinar), one had an implanted cortical stimulator targeting perirolandic area, and one had a cortical stimulator placed at the left frontal and supplementary motor area. The patient with both VNS (off) and DBS had a 50% reduction in seizures, whereas the other two patients with cortical stimulators were considered non-responders with no improvement in seizures. Compared with the early-onset group, the late-onset group experienced more sensory symptoms (47% vs. 3%, p-value < 0,001), were more likely to report seizure frequency reduction with immunotherapy (53% vs. 18%, p-value 0.011), and were more likely to have a reduction in seizure frequency related to antiseizure medications (41% vs. 15%, p-value 0.041). The late-onset group underwent fewer surgical epilepsy procedures than the early-onset group, including hemispherectomy (0% vs. 36.4%, p-value 0.004) and tailored resections (6% vs. 49%, p-value 0.003).
Conclusions: RS represents a rare condition that can be disabling at any age. Although it is a disorder primarily of early childhood onset, our study showed that onset at 12 years or older is not rare. Our cohort demonstrated differences in early and late onset RS. More sensory symptoms were reported by the late-onset RS group, which could have been related to this group being able to report these symptoms more easily. Late-onset RS patients underwent fewer surgical procedures as compared to the early-onset group.
References
1. Bien CG, Granata T, Antozzi C, Cross JH, Dulac O, Kurthen M, et al. Pathogenesis, diagnosis and treatment of Rasmussen encephalitis: a European consensus statement. Brain. 2005 Mar;128(Pt 3):454-71.
Funding: No funding was received for conducting this study.
Clinical Epilepsy