Authors :
Presenting Author: Naila Kausar, MD – Texas Tech University Health Sciences Center
Julia Guido, MS3 student – Neurology – TTUHSC; jessica Garcia chan, MD – Neurology Resident, Neurology, TTUHSC; Janice Rivera, MD – Neurology Resident, Neurology, TTUHSC; Jitherdhar Kandimalla, MD – Neurology Resident, TTUHSC; Salvador Cruz-Flores, MD – Chair neurology, Neurology, TTUHSC; paisith piriyawat, MD – Neurology Program director, TTUHSC; Sushma Yerram, MD – Clerkship Director, Neurology, TTUHSC
Rationale:
Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is the most recognized form of autoimmune encephalitis.
1 It presents with constellation of neurological symptoms due to NMDAR from neuronal cell surface. Relapses occur in 10-30% of cases, mainly within the two years from onset.
2 No guidelines regarding long term immunotherapy or surveillance for autoimmune cases exist.
Methods:
We present 39-year-old male with a 2016 history of anti-NMDA encephalitis (left temporal lobe) treated with IV steroids and two years of immunotherapy with mycophenolate (750 mg twice daily). After stabilization, immunotherapy and antiseizure meds were tapered. In July 2023, he presented with refractory status epilepticus and MRI showed opposite (right) temporal lobe encephalitis.
Results:
In July 2023, patient was treated with IV Methylprednisolone with transient improvement while EEG showed right hemispheric lateralized periodic discharges, brief ictal rhythmic periodic discharges treated with levetiracetam. In August 2023, patient deteriorated with lateralized periodic discharges with plus features and electrical seizures on EEG along with worsening of MRI brain findings. Infectious etiology was ruled out and patient was given IV immunoglobulin (2 g/kg over 4 days) and Methylprednisolone. Seizures partially controlled with fosphenytoin, valproic acid, topiramate, lacosamide. Given refractory seizures and worsening MRI findings, Rituximab (1g two weeks apart) was administered. He slowly responded and repeat MRI showed improvement. The NMDA receptor antibody ratio in the CSF increased from 1:40 (2016) to 1:160 (2023). In both episodes, Pan Scan was negative for malignancy.
Conclusions:
We present a recurrent NMDA encephalitis case, despite a favorable initial response, relapse was severe with super refractory status epilepticus unresponsive to first-line therapy.
2 With course of disease antibodies only detects in CSF.
3. Studies suggest immunotherapy and tumor removal if applicable, improves 81% of afflicted patients within 24 months.
4 Further research needed on treatment duration, risk factors, relapse timing, surveillance scans, and markers is crucial to help determine the duration for monitoring and prevent future relapse. This case highlights the significance of establishing guidelines for immunotherapy in autoimmune encephalitis.
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2 Chiang S, Garg T, Hu A, Amin H, Davalos-Balderas A, Alfradique-Dunham I, et al. Pearls & Oy-sters: Relapse of anti-NMDA receptor encephalitis after prior first- and second-line immunotherapy. Neurology. 2018;90(20):936-9.
3 Dalmau J, Lancaster E, Martinez-Hernandez E, Rosenfeld MR, Balice-Gordon R. Clinical experience and laboratory investigations in patients with anti-NMDAR encephalitis. Lancet Neurol. 2011;10(1):63-74.
4 Titulaer MJ, McCracken L, Gabilondo I, Armangue T, Glaser C, Iizuka T, et al. Treatment and prognostic factors for long-term outcome in patients with anti-NMDA receptor encephalitis: an observational cohort study. Lancet Neurol. 2013;12(2):157-65.
Funding: None