Impact of Confirmed Autoimmune Encephalitis on Brain Glucose Metabolism

Autoimmune Encephalitis Clinical Trial

— ENCEPHATAIP  

Official title:

Impact of Confirmed Autoimmune Encephalitis on Brain Glucose Metabolism : a Prospective FDG PET Study

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT06079294
• Other study ID #: APHP221163
• Status: Not yet recruiting
• Phase: N/A
• Start date: January 4, 2024
• Est. completion date: January 4, 2026

Study information

• Verified date: August 2023
• Source: Assistance Publique - Hôpitaux de Paris
• Contact: Aurélie Kas, Pr
• Phone: 01 42 17 62 81
• Email: aurelie.kas[@]aphp.fr
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Prospective cohort study evaluating FDG PET in 56 patients with confirmed autoimmune encephalitis - based on 2016 Graus criteria, and 2021 paraneoplastic neurological syndromes criteria - at the acute phase, before immunomodulating treatment, or within 10 days of treatment initiation.

Description:

Autoimmune encephalitis is a diagnostic challenge, and requires early diagnosis for improved neurological outcomes. FDG PET has shown very high sensitivity, suggesting better performances than MRI, but almost exclusively in small sized retrospective studies. Brain FDG PET is therefore not included in current diagnostic criteria, conversely to brain MRI. This study will include 56 patients with confirmed - seropositive or seronegative - autoimmune encephalitis, based on 2016 Graus criteria for autoimmune encephalitis and 2021 criteria for paraneoplastic neurological syndromes. The main objective is to conduct a prospective evaluation of the diagnostic value of FDG PET performed in the acute phase before treatment initiation, or within 10 days of treatment initiation. A follow-up PET performed 3 months after treatment initiation will also be performed and analysed for all patients as part of secondary objective analyses.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 56
• Est. completion date: January 4, 2026
• Est. primary completion date: November 4, 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Age = 18 years old
• Newly diagnosed autoimmune encephalitis based on at least 1 of the 3 following

criteria :

1. " Definite limbic autoimmune encephalitis " according to 2016 Graus et al. criteria

2. " Possible autoimmune encephalitis " according to 2016 Graus et al. criteria AND typical autoantibody detected in serum or CSF

3. " Probable or certain paraneoplastic neurological syndrome " according to Graus et al. 2021 criteria (excluding peripheral neurological syndromes)

• Less than 6 months since first neurological symptoms imputable to autoimmune encephalitis
• Affiliated or entitled to a social security system (except AME)
• Obtaining free, written and informed consent (patient or legal representative or the close relative) Exclusion criteria
• History of brain tumor, head trauma, infarction or cerebral hematoma likely to result in altered cerebral carbohydrate metabolism on PET
• Patients who hae been on immunotherapy (corticosteroid bolus, IVIg, plasma exchange, endoxan, rituximab or other immunotherapy) fr more than 10 days
• Pregnant or breast-feeding woman
• Ventilated intubated patient
• Absolute contraindication to MRI (Pacemaker, cochlear implant, etc.)
• Presence of cognitive disorders incompatible with goog cooperation with the PET scan
• Algic or agitated patient unable to remain immobile in supine position for 30 minutes
• Deprived of liberty or under a protective measure (guardianship or curatorship)
• Patient taking part in other interventional research involving radiopharmaceutical injections

Related Conditions & MeSH terms

• Autoimmune Diseases of the Nervous System
• Autoimmune Encephalitis
• Encephalitis
• Hashimoto Disease

Intervention

Other:
• FDG PET
Brain FDG PET performed 3 months after treatment initiation

Locations

Country	Name	City	State
France	Hospital Pitie Salpetriere	Paris

Sponsors (1)

Lead Sponsor	Collaborator
Assistance Publique - Hôpitaux de Paris

Country where clinical trial is conducted

France, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Main analysis of initial brain FDG PET	Automated region-based and voxel wise quantitative PET analysis, estimation of the proportion of patients with PET anomalies (overall and by region of interest).	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation)
Secondary	Analysis of follow-up brain FDG PET	Automated region-based and voxel wise quantitative PET analysis comparatively to initial brain PET	PET performed 3 months after treatment initiation, compared to initial brain PET
Secondary	Secondary analysis of initial brain FDG PET	Subgroup PET analysis according to autoantibody subtype or seronegative status	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation)
Secondary	Secondary analysis of initial brain FDG PET	Correlation of main analysis results to important clinical variables (clinical symptomatology (typology and duration of symptoms), MRI, cerebrospinal fluid (CSF), electroencephalogram (EEG).)	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation)
Secondary	Secondary analysis of initial brain FDG PET	PET voxel-wise connectivity analysis	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation)
Secondary	Secondary analysis of initial and follow-up brain FDG PET	Correlation of PET treatment response to clinical symptom treatment response	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation), and follow-up PET 3 months after treatment initiation
Secondary	Analysis of initial whole body FDG PET	Evaluation of whole body FDG PET diagnostic performance for identifying neoplasms in paraneoplastic syndromes	PET performed at the acute phase, before immunomodulating treatment (or within 10 days of treatment initiation)