title: Anti-NMDA Receptor Encephalitis in the Polar Bear (Ursus maritimus) Knut.
abstract: Knut the polar bear of the Berlin Zoological Garden drowned in 2011 following seizures and was diagnosed as having suffered encephalitis of unknown etiology after exhaustive pathogen screening. Using the diagnostic criteria applied to human patients, we demonstrate that Knut's encephalitis is almost identical to anti-NMDA receptor encephalitis which is a severe autoimmune disease representing the most common non-infectious encephalitis in humans. High concentrations of antibodies specific against the NR1 subunit of the NMDA receptor were detected in Knut's cerebrospinal fluid. Histological examination demonstrated very similar patterns of plasma cell infiltration and minimal neuronal loss in affected brain areas. We conclude that Knut suffered anti-NMDA receptor encephalitis making his the first reported non-human case of this treatable disease. The results suggest that anti-NMDA receptor encephalitis may be a disease of broad relevance to mammals that until now has remained undiagnosed.
authors: German Center for Neurodegenerative Diseases (DZNE) Berlin, Germany.|Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors: H
authors: H
authors: Prüss
authors: German Center for Neurodegenerative Diseases (DZNE) Berlin, Germany.
authors: J
authors: J
authors: Leubner
authors: German Center for Neurodegenerative Diseases (DZNE) Berlin, Germany.
authors: N K
authors: NK
authors: Wenke
authors: Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.
authors: G Á
authors: GÁ
authors: Czirják
authors: Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.
authors: C A
authors: CA
authors: Szentiks
authors: Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.
authors: A D
authors: AD
authors: Greenwood
mesh_terms: D000818:Animals; D060426:Anti-N-Methyl-D-Aspartate Receptor Encephalitis / Q000134:cerebrospinal fluid / Q000473:pathology*; D001323:Autoantibodies / Q000134:cerebrospinal fluid; D001344:Autopsy; D001483:Base Sequence; D001921:Brain / Q000473:pathology; D002460:Cell Line; D006801:Humans; D007136:Immunoglobulins / Q000134:cerebrospinal fluid; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D011485:Protein Binding; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014162:Transfection; D001503:Ursidae / Q000502:physiology*
chemical_list: D001323:Autoantibodies; D007136:Immunoglobulins; D016194:Receptors, N-Methyl-D-Aspartate