An Uncommon Presentation of a Primary Bone Tumor: Anti-AMPA (Anti-α-Amino-3-Hydroxy-5-Methyl-4-Isoxazolepropionic acid) Receptor Limbic/Paraneoplastic Encephalitis as a Presenting Feature of Ewing Sarcoma

Daniel Koh, Theodore Lau, Evonne Teoh, Kenneth K. Lau

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5 Citations (Scopus)


Anti-AMPA (anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor limbic encephalitis is a rare autoimmune syndrome. It can be associated with an underlying malignancy, such as lung, breast, or thymus. We are reporting a case of a 19-year-old patient who presented with a 2-week history of confusion and short-term memory loss. A magnetic resonance imaging of brain showed increased T2 hyperintensity within the hippocampi bilaterally. Cerebrospinal fluid analysis was positive for anti-AMPA receptor antibodies. A computed tomography revealed multiple pulmonary metastases as well as an expansile lucent and sclerotic lesion in the ilium, which was subsequently biopsied. Histopathology confirmed a diagnosis of Ewing sarcoma (ES). Fluorescence in situ hybridization testing of the specimen identified EWSR1 (22q12.2) signal rearrangements in 80% of cells scored. To date, this is the first case report describing anti-AMPA receptor limbic/paraneoplastic encephalitis as a presenting feature of ES. Although it is rare, the possibility of ES may be considered in young patients presenting with anti-AMPA receptor limbic encephalitis. ©

Original languageEnglish
Pages (from-to)555-557
Number of pages3
JournalJournal of Pediatric Hematology/Oncology
Issue number7
Publication statusPublished - Oct 2018


  • anti-AMPA receptor limbic encephalitis
  • Ewing sarcoma
  • paraneoplastic

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