Autoimmune encephalitis: an observational study from South India

Abstract

Background: Ever since AE was acknowledged as a potentially treatable cause of encephalitis, it has been increasingly recognised worldwide. Data suggests that these disorders are under-recognized, which calls for an increased awareness of the varying clinical, laboratory, electrophysiological and radiological presentations of the different types of autoimmune encephalitis. This cross-sectional observational study included all patients diagnosed with AE, who presented to a tertiary care centre from June 2016 to January 2021. Data were collected including patient’s demography, clinical, laboratory, radiological and electrophysiology studies, management and outcomes. Results: 31 study participants were included, of which 13 patients were anti-NMDA antibody positive, 12 patients were anti-LGI1 antibody positive, 2 patients were anti-CASPR2 antibody positive, 2 were positive for dual positive status (anti-LGi1 and anti-CASPR2), and one each for anti-GABA-B and anti-GAD 65. There was a marginal male predilection with overall seizures being the most common symptom (68%) followed by behavioural disturbance (64.5%), and impairment of consciousness (32.3%). Patients with Anti-NMDA encephalitis were likely to be young females, with CSF pleocytosis, a more protracted hospital course with more chances of relapse and residual disease, while the patients with anti-Lgi1 encephalitis were likely to be older males with a shorter, less severe hospital course. Conclusion: The present study detailed the demographic, clinical, imaging, laboratory and EEG characteristics of 31 AE patients from a tertiary centre. The findings concurred with the literature and demonstrate the diverse spectrum of clinical manifestations of patients with AE, present with.