Clinical, diagnostic and therapeutic spectrum of seropositive and seronegative autoimmune encephalitis: Single center cohort study of 51 cases
Fahmy L, Affan M, Memon AB, Cerghet M. Clinical, diagnostic and therapeutic spectrum of seropositive and seronegative autoimmune encephalitis: Single center cohort study of 51 cases. Neurology 2020; 94(15):3.
Abstract Objective: In this retrospective study, we compared the clinical characteristics, diagnostic and treatment paradigm of seropositive and seronegative autoimmune encephalitis (AE).
Background: AEs are severe inflammatory disorders of central nervous system. The diagnosis remain challenging and relies on the clinical manifestations, finding biomarkers and therapy response. However, this can be problematic given that antibody testing results are not readily available and negative testing does not exclude the diagnosis.
Design/Methods: Retrospective chart review of patients diagnosed with AE in the last 6 years was performed. Demographic, clinical presentation, laboratory, imaging, electrophysiologic and treatment data were recorded. The patients were divided into two groups, autoantibody positive AE (AE+) and autoantibody negative AE (AE−). Two sample two-tailed t-tests and Fisher exact tests were used to compare AE+ and AE− patients. All statistical analyses were conducted using STATA 14.2 for Mac.
Results: 51 patients with the diagnosis of AE were included, AE + (n=36) and AE− (n=15). Psychiatric symptoms at onset were more frequently seen in AE+ compared to AE− (38% vs 13%), while autonomic disorders were found only in AE+ (9%). CSF findings were similar between the two groups with exception of oligoclonal bands which were significantly abnormal in AE− (82% vs 40%, p= 0.03). Demographic data, MRI findings and EEG findings were similar between groups. Steroids were used more frequently in AE− compared to AE+ patients (87% vs 55%, p=0.03). PLEX more commonly in AE+ (30% vs 20%) while long term immunosuppressant more commonly in AE− (40% vs 18%).
Conclusions: In our cohort psychiatric manifestations and autonomic dysfunction at onset were more frequently seen in AE+. Positive oligoclonal bands in AE− patients may represent immunological response and guide clinicians to consider immunotherapy when clinical suspicion for AE is high. Early recognition of highly suggestive presentation despite negative autoantibodies is important for this potentially treatable disorders.