Neurological response to early removal of ovarian teratoma in anti-NMDAR encephalitis

Abstract

We report an 18-year-old woman with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, who developed psychiatric symptoms, progressive unresponsiveness, dyskinesias, hypoventilation, hypersalivation and seizures. Early removal of an ovarian teratoma followed by plasma exchange and corticosteroids resulted in a prompt neurological response and eventual full recovery. Serial analysis of antibodies to NR1/NR2B heteromers of the NMDAR showed an early decrease of serum titres, although the cerebrospinal fluid titres correlated better with clinical outcome. The patients' antibodies reacted with areas of the tumour that contained NMDAR-expressing tissue. Search for and removal of a teratoma should be promptly considered after the diagnosis of anti-NMDAR encephalitis.

Figure 1

Clinical course and serial analysis of anti-NMDAR antibodies. Serum and cerebrospinal fluid (CSF) were collected on days 18 (pre-treatment), 39 (post-treatment) and 120 (late post-treatment). The diluted values are indicated. mPSL = methylprednisolone; Operation = salpingo-oophorectomy.

Figure 2

Reactivity of patients’ antibodies with the tumour. Consecutive sections of the patients’ teratoma incubated with patient’s antibodies (A), anti-NR1 antibody (B) and MAP2 antibody (C). Note that the patients’ antibodies immunolabel the areas of the nervous system expressing NR1 (an obligatory subunit of the NMDAR). Stars are placed in the same region of the three consecutive sections. All sections were mildly counterstained with hematoxylin; original magnification ×400.