Frequency of anti-IgLON5 disease in patients who meet the clinical diagnostic criteria for progressive supranuclear palsy/corticobasal syndrome
Yoya Ono1, Akira Takekoshi1, Nobuaki Yoshikura1, Hiroshi Takigawa2, Ikuko Aiba3, Ritsuko Hanajima2, Hisanori Kowa4, Masato Kanazawa5, Takahiko Tokuda6, Aya Midori Tokumaru7, Mitsuya Morita8, Kazuko Hasegawa9, Kenji Nakashima4, Takeshi Ikeuchi10, Akio Kimura1, Takayoshi Shimohata1
1Department of Neurology, Gifu University Graduate School of Medicine, 2Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, 3Department of Neurology, National Hospital Organization Higashinagoya National Hospital, 4Department of Neurology, National Hospital Organization Matsue Medical Center, 5Department of Neurology, Brain Research Institute, Niigata University, 6Department of Functional Brain Imaging, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, 7Department of Diagnostic Radiology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, 8Rehabilitation Center, Jichi Medical University Hospital, 9Department of Neurology, National Hospital Organization, Sagamihara National Hospital, 10Department of Molecular Genetics, Niigata University Brain Research Institute
Objective:
To confirm the prevalence of anti-immunoglobulin-like cell adhesion molecule 5 (IgLON5) disease in patients who fulfill the diagnostic criteria for progressive supranuclear palsy (PSP) or corticobasal syndrome (CBS).
Background:
Anti-IgLON5 disease can present symptoms that mimic PSP and CBS, including vertical supranuclear gaze palsy and parkinsonism. Some patients who are diagnosed with PSP or CBS are expected to have anti-IgLON5 antibodies; however, the frequency of such patients remains unknown.
Design/Methods:
We included 360 subjects enrolled in the Japanese Longitudinal Biomarker Study in PSP and Corticobasal Degeneration (JALPAC). We noted the age and sex of each patient and evaluated their diagnosis using diagnostic criteria for each subtype of PSP (PSP with Richardson’s syndrome [PSP-RS], PSP with parkinsonism [PSP-P], PSP-pure akinesia with gait freezing [PSP-PAGF], and PSP with cerebellar ataxia [PSP-C]), and using the revised Cambridge criteria and Armstrong criteria for CBS. In patients who fulfilled any diagnostic criteria, we then tested serum anti-IgLON5 antibodies via a cell-based assay.
Results:
Of 360 subjects in JALPAC, 223 fulfilled at least one of the diagnostic criteria for possible or probable PSP/CBS. The median age of these 223 patients was 73 (range 51–88) years; 123 (55%) were male. The numbers of patients who met each set of criteria were as follows: PSP-RS, 52; PSP-PAGF, 6; PSP-C, 2; CBS, 117; PSP-RS and CBS, 37; PSP-PAGF and CBS, 4; PSP-RS and PSP-PAGF, 1; PSP-RS and PSP-P, 1; PSP-P and CBS, 1; PSP-RS, PSP-PAGF, and CBS, 1; and PSP-RS, PSP-C, and CBS, 1. All 223 patients were negative for anti-IgLON5 antibodies.
Conclusions:
Anti-IgLON5 disease is likely absent or extremely rare in patients who meet the diagnostic criteria for PSP/CBS and have typical clinical presentations. Atypical symptoms such as sleep disturbance, dysautonomia, and respiratory failure may be crucial clinical features of anti-IgLON5 disease with PSP-/CBS-like presentations.