Abstract Details

Title Frequency of anti-IgLON5 disease in patients who meet the clinical diagnostic criteria for progressive supranuclear palsy/corticobasal syndrome

Topic Autoimmune Neurology

Presentation(s) S22 - Autoimmune Neurology: Autoimmune Encephalitis and Other Antibody-associated Syndromes (5:18 PM-5:30 PM)

Poster/Presentation
Number 010

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.

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).

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.

Authors/Disclosures
Yoya Ono PRESENTER	Yoya Ono has nothing to disclose.
Akira Takekoshi	Akira Takekoshi has nothing to disclose.
Nobuaki Yoshikura, MD, PhD (Gifu univesity graduate school of medicine department of neurology)	Dr. Yoshikura has nothing to disclose.
	No disclosure on file
Ikuko Aiba	Ikuko Aiba has nothing to disclose.
Ritsuko Hanajima, MD, PhD	No disclosure on file
Hisanori Kowa, MD, PhD (National Hospital Organization Matsue Medical Center)	Dr. Kowa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for DAIICHI SANKYO COMPANY, LIMITED. Dr. Kowa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Eli Lilly Japan K.K.. Dr. Kowa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Otsuka Pharmaceutical Co., Ltd.. Dr. Kowa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Amgen Inc.. Dr. Kowa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Takeda Pharmaceutical Company Limited.. Dr. Kowa has received personal compensation in the range of $0-$499 for serving on a Speakers Bureau for Kyowa Kirin Co., Ltd.. Dr. Kowa has received personal compensation in the range of $0-$499 for serving on a Speakers Bureau for Chugai Pharmaceutical Co., Ltd.. Dr. Kowa has received personal compensation in the range of $0-$499 for serving on a Speakers Bureau for ONO PHARMACEUTICAL CO., LTD..
Masato Kanazawa, MD, FAAN (Niigata University)	Dr. Kanazawa has nothing to disclose.
	No disclosure on file
	No disclosure on file
Mitsuya Morita, MD, PhD (Jichi Medical Univeristy)	Dr. Morita has nothing to disclose.
Kazuko Hasegawa, MD (Dept Neurology, Sagamihara Natl Hospital)	Dr. Hasegawa has nothing to disclose.
	No disclosure on file
Takeshi Ikeuchi, MD (Brain Research Institute, Niigata University)	Dr. Ikeuchi has nothing to disclose.
Akio Kimura, MD (Gifu University Graduate School of Medicine)	Dr. Kimura has nothing to disclose.
Takayoshi Shimohata, MD, FAAN (Department of Neurology, Gifu University)	Dr. Shimohata has nothing to disclose.