Background: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a form of autoimmune encephalitis with paraneoplastic and nonparaneoplastic origin. Anti-NMDA receptor encephalitis preferentially affects children and young adults with a male/female ratio of 1/4. In case of clinical suspicion, electroencephalogram and brain magnetic resonance imaging (MRI) are useful. The diagnosis is confirmed by the detection of IgG antibodies directed against NMDA receptors. Treatment includes immunosuppression and tumour resection when indicated.Case Report: We report the case of a 24-year-old female admitted to the emergency room following the onset of acute confusion. Due to the rapid deterioration of consciousness and swallowing disorders, the patient was transferred to the intensive care unit. On day 23 after presentation, MRI suggested autoimmune limbic encephalitis. Serologic and cerebrospinal fluid results were positive for anti-NMDA antibodies. After intravenous methylprednisolone therapy and plasmapheresis and a second line therapy with corticosteroid therapy and mycophenolic acid, the patient’s clinical condition gradually improved.Why should an emergency physician be aware of this? : This disease is still underdiagnosed. The possibility of Anti-NMDA encephalitis must be excluded especially for young female adults and children presenting to emergency department with acute confusion before concluding a psychiatric disease diagnosis. Neurological deterioration typically occurs 1 to 3 weeks after the onset of symptoms.

Background: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a form of autoimmune encephalitis. Due to the variability of the initial symptoms, anti-NMDAR encephalitis is not only underdiagnosed but also can be misdiagnosed as viral encephalitis or other pathologies. The origin of this disease is often paraneoplastic. Anti-NMDAR encephalitis preferentially affects children and young adults, and it has a male/female ratio of 1/4. In case of clinical suspicion, electroencephalogram and brain magnetic resonance imaging are useful, but lumbar puncture for cerebrospinal fluid analysis is used to confirm the diagnosis. Treatment for this disease includes immunosuppression and tumour resection when indicated.Case presentation: We report the case of a 24-year-old female admitted to the emergency room following the onset of acute confusion. Due to the rapid deterioration of consciousness, swallowing disorders, respiratory failure and severe bradycardia the patient was intubated. On day 23 after presentation, brain magnetic resonance suggested autoimmune limbic encephalitis. Cerebrospinal fluid results were positive for anti-NMDA antibodies. After IV methylprednisolone and plasmapheresis and a second line therapy with corticosteroid and mycophenolic acid, the patient’s clinical condition gradually improved.Conclusions: Anti-NMDAR encephalitis typically occurs in young patients with no history of acute psychiatric symptoms. The possibility of this pathology should be taken into account before diagnosing a patient with a psychiatric illness.

Background: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a form of autoimmune encephalitis with paraneoplastic and nonparaneoplastic origin. Patients with this disease usually arrive at the intensive care unit without any diagnosis or with complications as a result of a delayed diagnosis. This disease is not well known and is underdiagnosed. Due to the variability of the initial symptoms and the lack of knowledge regarding these symptoms, anti-NMDA receptor encephalitis is not only underdiagnosed but also can be misdiagnosed as viral encephalitis or other pathologies. Anti-NMDA receptor encephalitis preferentially affects children (from 8 months) and young adults, and it has a male/female ratio of 1/4. In case of clinical suspicion, electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) are useful. The diagnosis is confirmed by the detection of IgG antibodies directed against NMDA receptors in serum and CSF. Treatment for this disease includes immunosuppression and tumour resection when indicated.Case presentation: We report the case of a 24-year-old female admitted to the emergency room following the onset of acute confusion. Due to the rapid deterioration of consciousness and swallowing disorders, the patient was transferred to the intensive care unit. On day 23 after presentation, MRI suggested autoimmune limbic encephalitis. Serologic and CSF results were positive for anti-NMDA antibodies. After IV methylprednisolone therapy and plasmapheresis and a second line therapy with corticosteroid therapy and mycophenolic acid, the patient’s clinical condition gradually improved.Conclusions: Anti-NMDA receptor encephalitis typically occurs in young patients with no history of acute psychiatric symptoms. The possibility of this pathology should be taken into account before diagnosing a patient with a psychiatric illness.