Impact of blood-brain barrier disruption on clinical features and treatment response in patients with newly diagnosed autoimmune encephalitis

Aims: Blood-brain barrier (BBB) breakdown is an essential mechanism in inflammatory diseases of the central nervous system. However, the association between BBB integrity and autoimmune encephalitis (AE) has not been investigated. Our study aimed to analyze this relationship in patients with AE between BBB integrity with clinical manifestations and therapeutic responses.Methods: Our study enrolled 147 patients with AE who were newly diagnosed at the First Affiliated Hospital of Zhengzhou University between August 2015 and December 2021. Patients were classified into normal or damaged BBB groups based on cerebrospinal fluid (CSF) albumin/serum albumin (QAlb). To evaluate the severity of the illness, we used the modified Rankin Scale (mRS) and the Clinical Assessment Scale for Auto immune Encephalitis (CASE).Results: We found a higher proportion of males, higher CSF protein, immunoglobulin IgG, and 24-h intrathecal IgG synthesis rate in the damaged BBB group. The improvement rate was lower in the damaged BBB group, but we found that double-or triple-combination immunotherapy had better clinical outcomes than single immunotherapy. In addition, there was a positive correlation between the CASE score and mRS score, and a positive correlation between the CASE score or mRS score and QAlb on admission. Conclusions: BBB integrity is closely related to the clinical features and treatment responses of newly diagnosed AE. Patients with AE and a damaged BBB may benefit from combination immunotherapy.