UNASSIGNED: Recently, cases of overlapping encephalitis caused by anti-N-methyl-D-aspartate receptor (anti-NMDAR) and anti-myelin oligodendrocyte glycoprotein (MOG) antibodies have been reported, and their clinical characteristics are gradually becoming clear. Acute-phase treatment typically involves the use of steroids, and although some studies have suggested that steroids can be effective, the extent of their efficacy has not yet been fully explored.
UNASSIGNED: We present the case of a 25-year-old man with anti-NMDAR and anti-MOG antibody overlapping encephalitis who showed considerable improvement after steroid treatment. To gain a deeper understanding of the efficacy of steroids in managing this condition, we conducted a literature review of cases of anti-NMDAR and anti-MOG antibody double-positive encephalitis that were treated with steroids during the acute phase. Thirteen cases were analyzed, including a new case diagnosed at our hospital. All patients showed improvement after receiving steroid treatment in the acute phase. Ten patients did not have any sequelae, and nine of them showed a rapid or major response during the acute phase. In contrast, three patients experienced sequelae (mild cognitive decline, visual impairment, and memory impairment, respectively), with their response to steroids in the acute phase being slow or limited. Relapses occurred in five patients, in one patient during steroid tapering, and in another two patients after cessation of steroids.
UNASSIGNED: Steroid therapy can be effective in the acute stage of anti-NMDAR and anti-MOG antibody overlapping encephalitis. A positive prognosis may be expected in patients who experience substantial improvement with steroid therapy during the acute phase.

Presented clinical observation of anti-NMDA-receptor encephalitis, which was first described in 2007, is rare and to date has not been sufficiently studied. The disease often manifests with psychopathological symptoms and catatonia, so patients are transferred into a mental healthcare institution and often require intensive care and resuscitation, due to the development of life-threatening respiratory and hemodynamic disorders. Diagnosis is based on detection of autoantibodies to the NR1- and NR2 subunits of the glutamate NMDA receptor in blood serum and cerebrospinal fluid. Pathogenesis-based therapy includes the administration of glucocorticoids and intravenous immunoglobulins, plasmapheresis, as well as the introduction of monoclonal antibodies in also used, and in severe cases, cytostatics are prescribed. The widespread comorbidity of anti-NMDA receptor encephalitis with ovarian neoplasms in women (up to 60%) requires appropriate diagnosis and early removal of ovarian neoplasms when they are detected. With timely diagnosis and adequate treatment strategies, the outcome of this rare disorder is usually positive.
Представлено клиническое наблюдение заболевания анти-NMDA-рецепторного энцефалита, которое впервые описано в 2007 г., является редким и к настоящему моменту недостаточно изученным. Заболевание обычно дебютирует с психопатологической симптоматики и кататонии, поэтому пациенты помещаются в психиатрическое учреждение и часто требуют интенсивной терапии и реанимационных мероприятий, что обусловлено развитием у них опасных для жизни дыхательных и гемодинамических нарушений. Диагностика состояния основывается на выявлении в плазме крови и цереброспинальной жидкости аутоантител к NR1- и NR2-субъединицам глутаматного NMDA-рецептора. Патогенетическая терапия предусматривает назначение глюкокортикоидов и внутривенных иммуноглобулинов, также используют плазмаферез и введение моноклональных антител, а в тяжелых случаях — цитостатики. Распространенная коморбидность анти-NMDA-рецепторного энцефалита с новообразованиями яичников у женщин (до 60%) требует проведения соответствующей диагностики и раннего удаления новообразований яичников при их обнаружении. При своевременной диагностике и адекватной лечебной тактике прогноз обычно благоприятный.

We described a challenging case of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis in a young girl. Despite enduring months of reduced consciousness with ongoing antibody presence, she ultimately exhibited remarkable improvement within a 5-year follow-up period. Additionally, we conducted a concise review of relevant literature on anti-NMDAR encephalitis, with a specific focus on anti-NMDAR antibodies. Our findings enhance the clinical comprehension of anti-NMDAR encephalitis and offer valuable insights to clinicians for its management.

Cerebellar ataxia is an uncommon and atypical manifestation of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, often accompanied by seizures, psychiatric symptoms, and cognitive deficits. Previous cases of isolated brainstem-cerebellar symptoms in patients with anti-NMDAR encephalitis have not been documented. This report presents a case of anti-NMDAR encephalitis in which the patient exhibited cerebellar ataxia, nystagmus, diplopia, positive bilateral pathological signs, and hemiparesthesia with no other accompanying symptoms or signs. The presence of positive CSF anti-NMDAR antibodies further supports the diagnosis. Other autoantibodies were excluded through the use of cell-based assays. Immunotherapy was subsequently administered, leading to a gradual recovery of the patient.

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is one of the most prevalent etiologies of autoimmune encephalitis. Approximately 25% of anti-NMDAR encephalitis cases prove refractory to both first- and second-line treatments, posing a therapeutic dilemma due to the scarcity of evidence-based data for informed decision-making. Intravenous rituximab is commonly administered as a second-line agent; however, the efficacy of its intrathecal administration has rarely been reported.
We report two cases of severe anti-NMDAR encephalitis refractory to conventional therapies. These patients presented with acute-onset psychosis progressing to a fulminant picture of encephalitis manifesting with seizures, dyskinesia, and dysautonomia refractory to early initiation of first- and second-line therapeutic agents. Both patients received 25 mg of rituximab administered intrathecally, repeated weekly for a total of four doses, with no reported adverse effects. Improvement began 2-3 days after the first intrathecal administration, leading to a dramatic recovery in clinical status and functional performance. At the last follow-up of 6 months, both patients remain in remission without the need for maintenance immunosuppression.
Our cases provide evidence supporting the intrathecal administration of rituximab as a therapeutic option for patients with refractory anti-NMDAR encephalitis. Considering the limited penetration of intravenous rituximab into the central nervous system, a plausible argument can be made favoring intrathecal administration as the preferred route or the simultaneous administration of intravenous and intrathecal rituximab. This proposition warrants thorough investigation in subsequent clinical trials.

OBJECTIVE: Teratoma is a type of germ cell tumor that derived from early embryonic stem cells and germ cell lines, which can lead to a rare complication known as paraneoplastic encephalitis syndrome. Delayed removal of teratoma allows for continuing antigen presentation, inducing affinity maturation of the antibody and the generation of long-lived plasma cells that infiltrate both bone marrow and brain, which makes the patient nonresponsive to later removal of teratoma and refractory to immunotherapy. We present this rare case to remind clinicians to be vigilant for the recognition and removal of teratoma during the treatment of autoimmune encephalitis.
METHODS: We retrospectively reviewed the clinical record of this 12-year 5-month-old female patient diagnosed with anti- N -methyl- d -aspartate receptor (anti-NMDAR) autoimmune encephalitis; her ovarian teratoma was unidentified on admission. She did not respond to immunosuppressive therapy until the mature ovarian teratoma identified 45 days after admission and removed the following day, nearly 2 months after symptom onset. This patient experienced nearly complete resolution of symptoms within the subsequent 2 weeks. In addition, we conducted a literature review of the clinical presentations and treatment of anti-NMDAR autoimmune encephalitis associated with ovarian teratoma in the pediatric population.
RESULTS: Our findings suggest that clinicians should be vigilant for the recognition and removal of teratoma during the treatment of autoimmune encephalitis.
CONCLUSIONS: Female pediatric patients with suspected anti-NMDAR encephalitis should be screened for ovarian tumors immediately and treated in a multidisciplinary setting including neurology and obstetrics and gynecology.

Anti-NMDAR encephalitis is the most common cause of immune-mediated catatonia.
Three females presented with neuropsychiatric symptoms and were empirically treated with first-line immunotherapy and ovarian teratoma resection for suspected autoimmune encephalitis, preceding diagnostic confirmation via NMDAR antibody positivity. They required escalating large doses of benzodiazepines for refractory malignant catatonia resulting in ICU level care. ECT treatments were initiated, and patients were gradually noted to have clinical improvement as was measured by the Bush-Francis Catatonia Rating Scale.
Clinicians should recognize catatonia among patients with suspected anti-NMDAR encephalitis and consider the early implementation of ECT into treatment algorithms.

Rationale: Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a form of autoimmune synaptic encephalitis, often mediated by neuronal surface antibodies. Clinically, it manifests through a diverse range of neurological and psychiatric symptoms, primarily affecting young women with ovarian teratoma, which is rare in pregnant women. Patient concerns: We report a case of a 35-year-old multiparous pregnant patient at 38 weeks of gestation presented to the emergency room with seizure, psychiatric symptoms like delirious speech with mystical visual and auditory hallucinations, bradylalia, and retrograde amnesia. Diagnosis: The diagnosis of autoimmune encephalitis with anti-NMDA antibodies was concluded by considering the lumbar puncture results, brain imaging, and the patient\'s persistent symptoms. Outcomes: This case is noteworthy for its rarity and the symptoms\' breadth. At 38 weeks of gestation, the patient underwent a cesarean section, resulting in excellent maternal recovery observed during the 6-month follow-up and good neonatal adaptation. Lessons: Our goals include raising awareness about this condition and emphasizing the significance of early diagnosis. This encephalitis is treatable and potentially reversible, underscoring the importance of prompt identification.

OBJECTIVE: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, among the paraneoplastic syndromes, is a recently characterized autoimmune encephalitis most commonly associated with antibodies against subunits of the NMDAR in the central nervous system. As a paraneoplastic syndrome, anti-NMDAR encephalitis is commonly associated with ovarian teratomas, small cell lung carcinomas and testicular germ cell tumors. To our knowledge, there have been no cases with primary central nervous system lymphoma (PCNSL), a rare type of extranodal non-Hodgkin\'s lymphoma, without lymph node involvement associated with anti-NMDAR encephalitis.
METHODS: A 58-year-old right-handed male patient with complaints of instability in walking for two months, progressively smaller handwriting, hallucinations when falling asleep or waking up, decreased memory, inability to maintain attention was admitted to our hospital for further diagnosis and treatment. Lumbar puncture was performed with the diagnosis of possible encephalitis after many further examinations and CSF studies revealed NMDAR antibody positivity, leading to the initial diagnosis of anti - NMDAR encephalitis. He was treated with high dose methylprednisolone and intravenous immunoglobulin. Due to the continuation of the patient\'s presenting symptoms and cranial magnetic resonance imaging findings, a stereotactic brain biopsy was performed from the area with contrast enhancement and the diagnosis was revised as PCNSL associated with NMDAR antibody positivity.
CONCLUSIONS: This report emphasizes the importance of anti-NMDAR encephalitis as a paraneoplastic syndrome in previously undiagnosed PCNSL. Therefore, it is crucial to be aware of anti-NMDAR encephalitis as a paraneoplastic neurological syndrome that can present with non-Hodgkin\'s lymphoma. It is necessary to continually observe the evolution of the disease and perform further diagnostic tests for early identification.

The overlapping of two or more types of neural autoantibodies in one patient has increasingly been documented in recent years. The coexistence of myelin oligodendrocyte glycoprotein (MOG) and N-methyl-d-aspartate receptor (NMDAR) antibodies is most common, which leads to a unique condition known as the MOG antibody and NMDAR antibody overlapping syndrome (MNOS). Here, we have reviewed the pathogenesis, clinical manifestations, paraclinical features, and treatment of MNOS. Forty-nine patients with MNOS were included in this study. They were young males with a median onset age of 23 years. No tumors were observed in the patients, and 24 of them reported prodromal symptoms. The most common clinical presentations were psychiatric symptoms (35/49) and seizures (25/49). Abnormalities on magnetic resonance imaging involved the brainstem (11/49), cerebellum (9/49), and parietal lobe (9/49). Most patients mostly responded to immunotherapy and had a good long-term prognosis. However, the overall recurrence rate of MNOS was higher than that of mono antibody-positive diseases. The existence of concurrent NMDAR antibodies should be suspected in patients with MOG antibody-associated disease having psychiatric symptoms, seizures, movement disorders, or autonomic dysfunction. Similarly, serum MOG antibody testing should be performed when patients with anti-NMDAR encephalitis present with atypical clinical manifestations, such as visual impairment and limb weakness, and neuroradiological findings, such as optic nerve, spinal cord, or infratentorial involvement or meningeal enhancement. Early detection of the syndrome and prompt treatment can be beneficial for these patients, and maintenance immunosuppressive therapy is recommended due to the high overall recurrence rate of the syndrome.