Multiple autoimmune antibody limbic encephalitis: a case in a pregnant woman

Abstract

OBJECTIVE:Outline the clinical course of a pregnant patient with multiple auto-antibody limbic encephalitis.BACKGROUND:Anti-NMDA receptor and anti-GAD antibody have both been associated with autoimmune limbic encephalitis. To our knowledge, no reports describe both of these antibodies in a single symptomatic patient.DESIGN/METHODS:Case report RESULTS:A 36 year old female presented with four days of confusion, hallucinations, hypersexuality, disinhibition and pressured speech. The patient was found to be hyperthyroid with anti-TPO and anti-TSI antibodies and no symptomatic resolution with Methimazole. Further testing showed anti-NMDAr antibody, anti-GAD antibody, and another neuronal auto-antibody yet to be characterized. The existence of her pregnancy was also discovered during the hospital course; thus, she was treated with seven cycles of PLEX. She was asymptomatic at discharge and at last follow-up at 37 weeks gestation.CONCLUSIONS:This patient was different from previously described cases of autoimmune encephalitis. First, it is unclear whether one of the antibodies was the dominant cause of encephalitis or if the three worked synergistically. Her titer of anti-NMDAr antibody (1:5) was significantly lower and her symptoms less severe than previously described cases (>1:80). She did not develop anti-GAD encephalitis symptoms such as cerebellar ataxia, epilepsy, or palatal tremor. Her symptoms manifested earlier in pregnancy (5 weeks gestation) compared to previous gravid patients who presented with anti-NMDAr encephalitis at 8, 14, or 17 weeks gestation. She responded well to PLEX with significant symptomatic improvement by the fifth cycle.A curious temporal relationship exists between the time of conception and onset of disease. Based on ultrasound dates, the patient conceived within days of presenting to our facility. Her symptoms began four days prior to presentation. Encephalitis in our patient could have been precipitated by pregnancy. Further studies will be needed to determine if this is simply correlation or if there is true causation.