AUTHOR=Guetta Michaël , Kas Aurélie , Aouidad Aveline , Soret Marine , Allenbach Yves , Bordonné Manon , Oppetit Alice , Raffin Marie , Psimaras Dimitri , Cohen David , Consoli Angèle 

TITLE=Relevance of Brain 18F-FDG PET Imaging in Probable Seronegative Encephalitis With Catatonia: A Case Report

JOURNAL=Frontiers in Psychiatry

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2021.685711

DOI=10.3389/fpsyt.2021.685711

ISSN=1664-0640

ABSTRACT=<p>Autoimmune encephalitis (AIE) is a rare, severe, and rapidly progressive encephalopathy, and its diagnosis is challenging, especially in adolescent populations when the presentation is mainly psychiatric. Currently, cerebral 18-fluorodeoxyglucose positron emission tomography (<sup>18</sup>F-FDG-PET) imaging is not included in the diagnosis algorithm. We describe a 16-year-old patient with probable seronegative encephalitis with catatonia for which several cerebral PET scans were relevant and helpful for diagnosis, treatment decision making, and follow-up monitoring. The patient recovered after 2 years of treatment with etiologic treatment of AIE and treatment of catatonia. This case suggests a more systematic assessment of the clinical relevance of <sup>18</sup>F-FDG-PET imaging in probable seronegative AIE.</p>