Autoimmune encephalitis and related disorders: A retrospective study of 43 cases in a tertiary hospital

Abstract Background Despite progresses in autoimmune encephalitis and related disorders (AERD), they remain a major challenge in daily clinical practice. Objectives To describe a tertiary hospital's longitudinal experience in AERD between 2005 and 2020. Methods Single-centre retrospective analysis of 43 patients. Results 43 patients were included, 55.8% with positive antibodies (10 antiGAD, 4 antiNMDAR, 2 antiGABABR, 2 antiLGI1, 2 antiCASPR2, 1 antiIgLON5, 1 antiHu, 1 antiYo, 1 antiCV2 and 1 antiMa2, detecting coexisting antibodies in one patient: antiNMDAR + antiGABABR); 28% with negative antibodies; and 16.2% with steroid responsive encephalitis associated to antithyroid antibodies (SREAT). The median age was 62 year-old [14–88]. Females (62.8%) outnumbered males (37.2%). Limbic encephalitis was the most common clinical syndrome (60.5%), followed by SREAT (16.2%), autoimmune cerebellitis (9.3%), stiff-person syndrome (7%), antiNMDAR-encephalitis (5%) and antiIgLON5 encephalopathy (2%). CSF showed pleocytosis and/or hyperproteinorrhachia in 54.2%. MRI was unremarkable in 60%. Brain SPECT/PET showed hyperperfusion/hypermetabolism of limbic areas in 60% of patients to whom it was performed. Antibody-positivity was significantly associated with satisfaction of diagnostic criteria at high levels of certainty (p  Conclusions AERD's diagnostico and treatment have significantly improved over the last years. However, several limitations remain, particularly concerning antibody-negative AERD. The proposed diagnostic criteria might be still too reliant on antibody-positivity. Antibody-status seems to condition treatment escalation. The creation of a Neuroimmunology Unit optimized AERD's management in clinical practice.