Shan Qiao,1,2,* Chong Zhang,1,3,* Haiyun Li,4,* Tianyu Zhou,1,3 Aihua Wang,1 Shanchao Zhang1,5,6 

1Department of Neurology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Institute of Neuroimmunology, Jinan, People`s Republic of China; 2Department of Medical Genetics, School of Basic Medical Sciences, Cheeloo College of, Medicine, Shandong University, Jinan, People’s Republic of China; 3Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, People`s Republic of China; 4Department of Geriatric Medicine, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China; 5School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China; 6Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing, People`s Republic of China

*These authors contributed equally to this work

Correspondence: Shanchao Zhang, Department of Neurology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Institute of Neuroimmunology, Jinan, People`s Republic of China, Email zhangshanchao2012@163.com

Purpose: The present study aimed to examine the clinical distinctions among patients with neuronal surface antibody-associated autoimmune encephalitis (NSAE) diagnosed with anti-N-methyl-D-aspartate receptor encephalitis (NMDAR-E), anti-leucine-rich glioma-inactivated 1 encephalitis (LGI1-E), and anti-gamma aminobutyric acid-B receptor encephalitis (GABABR-E), compared with those with viral encephalitis (VE). Additionally, the study aimed to assess the impact of cerebrospinal fluid (CSF) oligoclonal bands (OCBs) on the severity and prognosis of NSAE.
Patients and Methods: This retrospective analysis included patients with NSAE, encompassing NMDAR-E, LGI1-E, and GABABR-E, alongside individuals with VE. Participants with NSAE were categorized into two groups based on the presence or absence of CSF-specific OCBs. Data regarding demographics, clinical manifestations, magnetic resonance imaging (MRI) findings, CSF analyses and prognosis were collected and analyzed.
Results: The findings indicated that younger female with NSAE exhibited a higher incidence of seizure onset, disruption of the blood-CSF barrier (BCSFB), and elevated QAlb/QLim ratios compared to VE patients, with NSAE patients demonstrating more severe clinical outcomes at discharge. Among the 185 NSAE patients, 43 (23.24%) were positive for OCBs, while 142 (76.76%) negative. The OCB-positive cohort displayed a greater prevalence of younger females and NMDAR-E (both P< 0.05). No significant differences were observed in CSF white blood cell counts, protein concentrations, or immunoglobulin G levels between the two groups (all P> 0.05). The modified Rankin Scale (mRS) scores at discharge and the final follow-up were higher in the OCB-positive group than the OCB-negative group (both P< 0.05). Both univariate and multivariate analyses identified OCBs and NSAE subtypes as independent risk factors influencing the clinical prognosis of NSAE.
Conclusion: In comparison to VE patients, NSAE patients with positive OCBs were more frequently female and exhibited CSF pleocytosis, particularly among those with NMDAR-E. Importantly, the presence of positive OCBs emerged as an independent predictor of unfavorable outcomes in patients with NMDAR-E, LGI1-E, and GABABR-E.

Keywords: autoimmune encephalitis, oligoclonal bands, prognosis, cerebrospinal fluid, viral encephalitis