Session Information
Date: Monday, June 20, 2016
Session Title: Parkinsonism, MSA, PSP (secondary and parkinsonism-plus)
Session Time: 12:30pm-2:00pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: To describe a patient with a 12 –month history of progressive disorder suggestive of PSP-like syndrome, who was found to have anti-Leucin-rich Glioma Inactivated-1 (LGI1) encephalitis.
Background: Anti-LGI1 encephalitis is a novel, immunotherapy-responsive type of antibody-mediated autoimmune encephalitis. The clinical phenotype is rather stereotypic with limbic involvement, frequent seizures and memory disturbance. As seizures can be atypical, the memory issues can be the main problem resembling rapidly progressive dementia. To our best knowledge no previous cases has been reported mimicking a PSP-like syndrome.
Methods: We describe a 61-year-old man with a 12-month history of progressive behavioral and neuropsychiatric disorders, cognitive impairment, supranuclear ophtalmoplegia, postural instability with falls and parkinsonism.
Results: Neurological examination revealed supranuclear gaze palsy, postural instability with frequent backward falls, a bilateral rigid-akinetic parkinsonism. An extended cognitive battery assessment disclosed a subcortical cognitive impairment. Magnetic resonance imaging showed a moderate atrophy and a brain 18F-FDG PET was normal. Blood work was normal; HIV and VDRL serology were negative. Cerebrospinal fluid showed moderate pleocytosis (10 cells) and elevated protein levels (75 mg/L). Rapidly progression supported testing for antibodies. Voltage-gated potassium channel-radioimmunoassay (VGKC-RIA) was titer 1:32 in serum. Cell-based assay was positive for LGI1- antibodies (highly positive), and confirmed by the specific hippocampal pattern by immunohistochemistry. An extensive evaluation for malignancy was negative. Immunosuppressive therapy, including corticoid therapy and hyperimmune gammaglobulin, failed to show improvement. Rituximab therapy was started and a moderate treatment benefit was noted on cognitive battery assessment and UPRDS motor score.
Conclusions: We present a very atypical case of anti-LGI1 encephalitis. There is a growing interest in antibodies in patients with causing rapidly progressive dementia. Our case highlights the need to consider immune-mediated mechanisms in patients presenting with rapidly progressive dementia, including atypical PSP-like syndromes.
To cite this abstract in AMA style:
G.A. Da Prat, E.M. Gatto, G.G. Persi, V. Parisi, D. Lisei, L. Rattagan, M. Bres Bullrich, S. Camerlingo, C. Rugilo, M. Titulaer, G. Rojas. Anti-LGI1 encephalitis presenting as a progressive supranuclear palsy-like syndrome [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/anti-lgi1-encephalitis-presenting-as-a-progressive-supranuclear-palsy-like-syndrome/. Accessed June 14, 2025.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/anti-lgi1-encephalitis-presenting-as-a-progressive-supranuclear-palsy-like-syndrome/