Novel FDG-PET findings in anti-NMDA receptor encephalitis: a case based report

• Published in: Journal of child neurology Vol. 26; no. 10; p. 1325
• Main Authors: Maqbool, Mohsin, Oleske, Deanna A, Huq, A H M, Salman, Bassel A, Khodabakhsh, Kevin, Chugani, Harry T
• Format: Journal Article
• Language: English
• Published: United States 01.10.2011
• Subjects: Adolescent; Anti-N-Methyl-D-Aspartate Receptor Encephalitis - diagnostic imaging; Anti-N-Methyl-D-Aspartate Receptor Encephalitis - pathology; Cerebellar Cortex - diagnostic imaging; Fluorodeoxyglucose F18; Humans; Magnetic Resonance Imaging; Male; Positron-Emission Tomography
• ISSN: 1708-8283
• DOI: 10.1177/0883073811405199

The clinical manifestation and nuclear imaging findings in a 15-year-old boy with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis are described in this case report. The previously healthy patient presented with new onset hallucinations, seizure, and within a week, his mental status rapidly deteriorated to nonverbal with oro-lingual-facial dyskinesias. An extensive laboratory work-up for encephalopathy was negative. Repeated brain magnetic resonance imaging (MRI) studies were normal. On day 26 of admission, nuclear imaging using fluorodeoxyglucose positron emission tomography (FDG-PET) showed global hypometobolism with a prominent focally intense hypermetabolic lesion in the right cerebellar cortex. Diagnosis of anti-NMDAR encephalitis was confirmed with quantitative serology. The patient showed clinical signs of improvement after 2 courses of intravenous immunoglobulin therapy over 4 weeks. On day 46, repeat brain FDG-PET showed overall improvement but in contrast to the previous, the right cerebellar cortex showed focal hypometabolism. This is the first reported case of such findings using FDG-PET in anti-NMDAR encephalitis.