Acute Bulbar Palsy as Presentation of Anti-NMDA Receptor Encephalitis: A Case Report (P4.064)

OBJECTIVE: To report a case of anti-NMDA receptor (NMDAR) encephalitis presenting as acute bulbar palsy. BACKGROUND: Acute bulbar palsy as the first manifestation of anti-NMDAR encephalitis has not been previously reported. DESIGN/METHODS: A case report. RESULTS: This 37-year-old pregnant woman was admitted to our hospital with rapidly progressive bulbar palsy at 35 weeks of gestation. Two weeks before admission, the patient began to have numbness in the face and tongue. One day before admission, dysarthria and dysphagia developed. On admission (day 1), physical examination was unremarkable. On day 3, the patient was referred to our neurology department. On neurologic examination, she was alert, and cognitively intact, but she had severe bulbar palsy; she could not stick out her tongue. She had no ptosis or ocular movement abnormalities. The remaining neurologic examination was normal. Antibody testing for acetylcholine receptor, muscle specific kinase, GM1, GQ1b, and GT1a was negative. CSF examination revealed mild pleocytosis (white blood cells 13/µl), without oligoclonal bands. HSV-1 PCR was negative. Brain MRI was unremarkable. On day 3 she underwent caesarean section, and she was started on intravenous immunoglobulin (IVIg) under ventilatory support. On day 4 no waning phenomenon was seen. Nocturnal delirium, horizontal nystagmus, bradycardia, hypersalivation, diaphoresis, and apnea subsequently developed. On day 7 she received intravenous high-dose methylprednisolone (IVMP). No ovarian teratoma was identified but on day 20 high titers of CSF anti-NMDAR antibodies were detected. On day 21 she received intravenous high-dose cyclophosphamide (IVCPA). After an additional course of IVMP, IVIg and IVCPA, the patient remarkably improved with reduction of anti-NMDAR antibody titers. CONCLUSIONS: This disorder can present as acute bulbar palsy. This case highlights the importance of early detection of anti-NMDAR antibodies in a setting of acute bulbar palsy without other muscle weakness, ptosis, areflexia, psychosis, dyskinesias, seizures, or altered level of consciousness. Disclosure: Dr. Iizuka has nothing to disclose. Dr. Nakamura has nothing to disclose. Dr. Ishima has nothing to disclose. Dr. Kaneko has nothing to disclose. Dr. Dalmau has received personal compensation in an editorial capacity for Up To Date. Dr. Dalmau has received royalty payments from Athena Diagnostics. Dr. Dalmau has received research support from Euroimmun. Dr. Nishiyama has received research support from Otsuka Pharmaceutical Company, GlaxoSmithKline, Boehringer Mannheim, and Japan Mesiphisicx.