Abstract
RATIONALE: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disease that is associated with cell-surface NMDAR-targeting autoantibodies. Typical anti-NMDAR encephalitis symptoms include psychosis, seizure and extrapyramidal side effects. However, early diagnosis of anti-NMDAR encephalitis remains challenging due to the complexity of the motor phenomenon. PATIENT CONCERNS: Here, we report a new diagnosis of anti-NMDAR encephalitis in a young woman with a history of epilepsy. DIAGNOSES: Electroencephalography revealed a typical "extreme delta brush" pattern, which indicated anti-NMDAR encephalitis. INTERVENTIONS: The clinical status of the patient markedly improved after immediate and aggressive immunosuppression therapies. OUTCOMES: The patient was discharged with mild cognitive impairment. However, this was completely resolved 1 month postdischarge. LESSONS: We conclude that subacute onset focal seizure with psychosis as well as compatible electroencephalography findings (i.e., extreme delta brush patterns) should be considered notable early indicators of anti-NMDAR encephalitis. This would ensure early and effective clinical interventions, which are essential for favorable outcomes.