Anti-N-methyl-D-aspartate receptor encephalitis with accompanying ovarian teratoma in female patients from East China: Clinical features, treatment, and prognostic outcomes

Purpose: The association between anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDAR encephalitis) and teratoma is formally recognized. This study compared the clinical features, treatments and outcomes between female patients with or without accompanying teratomas and determined the potential influences of coexisting teratomas. Method: Fifty-six female patients diagnosed with anti-NMDAR encephalitis were enrolled in two major tertiary hospitals in East China from January 2013 through March 2018 and were grouped as patients with or without teratoma. The clinical features were reviewed, and follow-up studies were performed. Comparisons were made between the two groups. Results: Patients with teratoma reported fewer viral prodromes (p = 0.0085) and stronger positive intensity of anti-NMDAR antibodies in cerebrospinal fluid (CSF) (p = 0.0368), while nontumor patients tended to demonstrate lymphocytic pleocytosis in CSF (p = 0.0306). Seizure types varied between individuals, with complex partial seizures more common in teratoma patients (p = 0.0105). Nontumor patients frequently required combinations of first-line and second-line immunotherapy (p = 0.0014), which may be attributed to higher mRS scores at admission (p = 0.0300). Also, they had higher mean mRS scores since the 12-month follow-up and greater probability of relapse than did patients with teratomas (p = 0.0286). Conclusions: Symptomatology and auxiliary findings indicate that ovarian teratoma may be the immunologic trigger for anti-NMDAR encephalitis patients, while viral infection is likely to play a major part in pathogenesis for those without any detectable tumor. Overall, anti-NMDAR encephalitis patients with teratomas present with milder neurological symptoms and have better long-term outcomes after tumor removal.