Journal of Neuroimmunology

Limbic encephalitis in a child with ovarian teratoma and influenza B. Case report and critical review of the history of autoimmune anti-N-methyl-d-aspartate receptor encephalitis

We report the appearance of clinical symptoms and signs of N-methyl-d-Aspartate (NMDA) receptor encephalitis in a patient presenting just days after contraction of influenza B. The offending mature ovarian teratoma was identified and removed on the 10th day after the appearance of symptoms, with subsequent nearly complete resolution of symptoms over the subsequent 6 months. We provide a focused literature review of the clinical and pathophysiologic literature of anti-NMDA receptor encephalitis pertaining to influenza B virus and the pediatric population. Taken together, this study contributes to the pathophysiological understanding of anti-NMDA receptor encephalitis and aids clinicians in its early recognition and management.

Immature ovarian teratomas in anti-NMDA receptor encephalitis

Anti-N-methyl-d-aspartate receptor autoimmune encephalitis (NMDAR-AIE) is an immune-mediated neurological disease with manifestations including altered mental status, neuropsychiatric disturbance, movement disorders, seizure, and dysautonomia. NMDAR-AIE is associated with ovarian teratoma in half of cases, typically mature teratoma. NMDAR-AIE is rarely associated with immature ovarian teratomas. Here, we describe three cases of NMDAR-AIE associated with immature ovarian teratomas. We review diagnosis and management of immature ovarian teratomas in NMDAR-AIE as a collaboration between gynecology and neurology, with multi-disciplinary recommendations provided regarding workup and management.

Autoimmune encephalitis following bevacizumab therapy in ovarian carcinoma: A case report and review

Autoimmune encephalitis (AE) is increasingly recognized in clinical practice, yet drug-related encephalitic syndromes remain a diagnostic challenge. Immune checkpoint inhibitors (ICIs) are well-established triggers, whereas vascular endothelial growth factor (VEGF) inhibitors such as Bevacizumab are only rarely implicated, with evidence confined to case reports. Awareness of this association is essential as targeted therapies gain prominence in metastatic cancer care. We describe a 58-year-old woman with hypothyroidism and advanced ovarian carcinoma, who had previously undergone surgery and adjuvant chemotherapy in 2022 and metastasectomy for bowel involvement in 2024. She was in remission under Bevacizumab-chemotherapy combination therapy when, following reoperation for peritoneal adhesions in February 2025, she developed two episodes of transient loss of consciousness. During the attacks, fluctuating blood pressure, visual phenomena, and transient foreign-language speech were observed. MRI initially revealed left occipital leptomeningeal enhancement, and EEG showed lateralized epileptiform discharges and non-convulsive status epilepticus was considered. Although initial events were interpreted as seizure-related changes, follow-up imaging on day 15 revealed persistent abnormalities with new cortical and thalamic FLAIR hyperintensities. Neurological examination demonstrated drowsy consciousness, right homonymous hemianopia, motor aphasia, dystonic posturing of the right hand, and sensory integration deficits. Cerebrospinal fluid cytology, paraneoplastic, and autoimmune antibody panels were negative. Pulse intravenous methylprednisolone was initiated, leading to significant clinical improvement and partial radiologic regression, although word-finding difficulties persisted at last follow-up. This case illustrates an atypical, steroid-responsive encephalitic syndrome temporally associated with Bevacizumab. Unlike the well-characterized bilateral parieto-occipital patterns of PRES, our patient demonstrated unilateral leptomeningeal and cortical-thalamic involvement. The case underscores the importance of repeated neuroimaging, systematic exclusion of alternative etiologies, and timely immunotherapy in suspected drug-related encephalitis. Accumulation of further cases will be essential to clarify incidence, mechanisms, and optimal management of Bevacizumab-associated encephalitis.

Electroconvulsive therapy for catatonia in anti-NMDA receptor encephalitis: A case series

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.

Effect and timing of operative treatment for teratoma associated N-Methyl-d-Aspartate receptor-antibody encephalitis: A systematic review with meta-analysis

Resection of an underlying ovarian teratoma in patients with N-Methyl-d-Aspartate receptor (NMDAR)-antibody encephalitis is supported by pathophysiological studies demonstrating the production of NMDAR antibodies within the teratoma. This systematic review assesses the clinical effect of teratoma resection and compares early versus late resection. Literature search was performed on the first of October 2022 (MEDLINE, Embase, CENTRAL, Web of Science). Original studies including more than three patients with NDMAR encephalitis and associated ovarian teratoma were included and evaluated with the Study Quality Assessment Tool for risk of bias. Fourteen studies referring to 1499 patients were included and analyzed in four syntheses using the fixed Mantel-Haenszel method. The rate of relapse in patients with ovarian teratoma resection was lower than in patients without resection (risk ratio for relapse 0.30, 95% CI 0.17-0.51), however the certainty level of evidence is very low. Despite some evidence pointing to a beneficial effect of early teratoma resection in patients with NMDAR-antibody encephalitis, systematically accessible data are insufficient to provide recommendations for or against resection, as well as for timing of surgery. The authors received no financial support for the research, authorship, or publication of this article. For the systematic review no clinical-trial database registration had been done.