Retrospective Analysis of the French National Cohort of Patients With GAD Antibodies and Cerebellar Ataxia (Ata-GAD)

Glutamic acid decarboxylase (GAD) is an enzyme whose function in the body is to decarboxylate glutamate to GABA. GAD65 antibodies (GAD65Ab) have been associated with type-1 diabetes (80% of new-onset patients) and various neurological conditions, mainly stiff-person syndrome (SPS/PERM), cerebellar ataxia (CA), limbic encephalitis (LE) and temporal lobe epilepsy. These syndromes all seem to result from a reduced transmission of GABA. These neurological conditions are rare and can cause symptoms like confusion, memory loss, muscle stiffness, muscle spasms, behavioural disorders, and pharmacoresistant epilepsy. When finding high levels of GAD65-Ab in the serum, a cerebrospinal fluid (CSF) sample should be taken to look for oligoclonal IgG bands and intrathecal GAD-Ab production to prove an auto-immune cause for the various neurological symptoms.

Study Overview

• Status: Recruiting
• Conditions: GAD-receptor Antibodies-associated Encephalitis
• Intervention / Treatment: Other: GAD patients

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Marine Villard, doctor; Phone Number: +33 4 27 85 54 60; Email: marine.villard@chu-lyon.fr
• Study Contact Backup: Name: Jérôme Honnorat, professor; Phone Number: +33 4 72 35 78 06; Email: jerome.honnorat@chu-lyon.fr

Study Locations

• France
  • Bron, France, 69677
    • Recruiting
    • Hôpital Neurologique Pierre Wertheimer / Groupement Hospitalier Est
    • Contact: Jérôme Honnorat, professor; Phone Number: +33 4 72 35 78 06; Email: jerome.honnorat@chu-lyon.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Patient with cerebellar ataxia and GAD antibody

Description

Inclusion Criteria:

• neurological symptoms with GAD antibody
• GAD antibody in sera and/or CSF
• patient with cerebellar ataxia

Exclusion Criteria:

• tested positive to another antibody.
• no data
• any test in paraneoplastic neurological syndrome and autoimmune encephalitis center

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Anti-GAD encephalitis; This is a non-interventional study involving clinical data. This data are information of medical follow up on patient like diagnosis, symptoms, biological results, cancer, treatments.	Other: GAD patients; Describe the clinical and demographic characteristics of patients with anti-GAD65 antibody associated cerebellar ataxia.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
GAD Patient	Description of clinical data in patients with cerebellar syndrome associated with anti-GAD antibodies	Baseline

Collaborators and Investigators

• Sponsor: Hospices Civils de Lyon

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2023
• Primary Completion (Actual): January 1, 2024
• Study Completion (Estimated): June 30, 2024

Study Registration Dates

• First Submitted: March 21, 2024
• First Submitted That Met QC Criteria: March 21, 2024
• First Posted (Actual): March 28, 2024

Study Record Updates

• Last Update Posted (Actual): March 28, 2024
• Last Update Submitted That Met QC Criteria: March 21, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Dyskinesias; Cerebellar Diseases; Neuroinflammatory Diseases; Encephalitis; Ataxia; Cerebellar Ataxia
• Other Study ID Numbers: 69HCL24_0297

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No