Introduction: In young females anti-NMDAR encephalitis is often associated with an ovarian teratoma. Tumor resection and conventional immunotherapies are first-line treatment. However, 20-50% of patients have a suboptimal response. Rituximab, a monoclonal antibody directed against CD20 positive B cells, is a second-line treatment that has been shown to improve outcomes in pediatric patients. We present a severe case of anti-NMDAR encephalitis refractory to teratoma resection, conventional immunotherapies, and second line immunotherapy requiring Tocilizumab. Description: A 15-year-old previously healthy obese female presented with acute altered mental status, seizures, psychosis, fever, and gait instability. Serum and CSF confirmed anti-NMDAR encephalitis. Day 5 she required endotracheal intubation secondary to worsening altered mental status. A 6.6cm left adnexal mass was resected on day 6 and confirmed a mature cystic teratoma. She failed to show any clinical improvement 3 weeks into admission despite tumor resection and first-line immunotherapy, including high dose steroids, intravenous immunoglobulins, and plasmapheresis. Rituximab 1000mg was given, and while the patient was able to be successfully extubated, she remained significantly altered, agitated, and at times unable to follow commands. A 2nd dose of Rituximab 1000mg was given with no further clinical improvement. Tocilizumab, an anti-interleukin-6 monoclonal antibody, was given week 7 as a single 8 mg/kg dose, and the patient demonstrated rapid improvement in neurologic status. She was transferred to an acute rehabilitation center after 2.5 months of ICU stay with cognitive, speech, and motor deficits. Complications during hospital stay included prolonged intubation, ventilator associated pneumonia, tracheal stenosis, delirium, autonomic instability, and malignant catatonia. At 3-month follow-up she showed remarkable recovery and had returned to her neurological baseline. Discussion: This case highlights the need for both further research and early consideration of the use of Tocilizumab in Rituximab refractory anti-NMDAR encephalitis.
Said et al. (Sun,) studied this question.