Search

Background: Encephalitis originates from diverse autoimmune and infectious etiologies. Diagnostic challenges arise due to the spectrum of presentation and the frequent absence of specific biomarkers. This study aimed to comprehensively characterize and differentiate autoimmune encephalitis (AE) from infectious encephalitis (IE) in adults, and disentangle clinical, paraclinical, and therapeutic differences., Methods: A cohort study spanning 10 years was conducted across three Austrian tertiary care hospitals. Inclusion criteria comprised adults with probable or definite encephalitis. Demographics, clinical features, technical findings, treatment modalities, and outcomes were collected from the electronic patient files. A follow-up was performed via telephone interviews and clinical visits., Results: Of 149 patients, 17% had AE, 73% IE, and 10% encephalitis of unknown etiology. Significant differences between AE and IE included the prevalence of acute symptomatic seizures (AE: 85% vs. IE: 20%, p < 0.001), fever (8% vs. 72%, p < 0.001), headache (15% vs. 61%, p < 0.001), and focal neurological deficits (56% vs. 23%, p = 0.004), respectively. Paraclinical differences comprised lower CSF pleocytosis in AE compared to IE (median 6 cells/µl vs. 125 cells/µl, p < 0.001). Epileptic discharges on EEG and MRI lesions were more prevalent in AE than IE (50% vs. 14%, p < 0.001; 50% vs. 28%, p = 0.037). The modified Rankin Scale scores at discharge and last follow-up (median duration 2304 days, IQR 1433-3274) indicated favorable outcomes in both groups., Conclusion: This comprehensive analysis provides insights into the epidemiology, clinical, paraclinical, and therapeutic aspects and the outcomes of AE and IE in adults. We developed a diagnostic tool that facilitates early differentiation between AE and IE, aiding in timely therapeutic decision-making., Competing Interests: Declarations. Conflicts of interest: Tim J von Oertzen has received payment or honoraria for lectures, presentations, or manuscript writing support from Angelini Pharma, Eisai, GW Pharmaceuticals, Jazz Pharma, Livanova, and UCB Pharma and has served on advisory boards for Angelini Pharma, Arvelle Therapeutics, GW Pharmaceuticals, Jazz Pharma, and Zogenix Pharma outside the submitted work. Judith Wagner has received payment or honoraria for lectures, presentations, or travel grants from Boehringer Ingelheim, Janssen-Cilag GmbH, Pfizer Pharma GmbH, Novartis Pharma GmbH, Roche Austria GmbH, and UCB Pharma AG and has served on advisory boards for Janssen-Cilag GmbH and Novartis Pharma GmbH outside the submitted work. Daniel Schwarzenhofer reports an unrestricted grant by Boehringer Ingelheim RCV GmbH & Co. Eugen Trinka reports personal fees from EVER Pharma, Marinus, Arvelle, Angelini, Argenx, Medtronic, Biocodex, Bial-Portela & Cª, NewBridge, GL Pharma, GlaxoSmithKline, Boehringer Ingelheim, LivaNova, Eisai, Epilog, UCB, Biogen, Sanofi, Jazz Pharmaceuticals, and Actavis. His institution received grants from Biogen, UCB Pharma, Eisai, Red Bull, Merck, Bayer, the European Union, FWF Österreichischer Fond zur Wissenschaftsforderung, Bundesministerium für Wissenschaft und Forschung, and Jubiläumsfond der Österreichischen Nationalbank. All the other authors report no conflicts of interest., (© 2024. The Author(s).)