Objective:To analyze and summarize the clinical characteristics of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis patients with cerebellar ataxia.Methods:The clinical manifestations, laboratory examinations, treatment and prognosis of anti-NMDAR encephalitis patients with cerebellar ataxia diagnosed and treated in Peking Union Medical College Hospital from 2011 to 2019 were retrospectively analyzed.Results:About 4.3% (15 cases) of a total of 347 anti-NMDAR encephalitis patients were complicated with cerebellar ataxia, of which one patient had ovarian teratoma. There were seven male cases and eight female cases, with a median age of 28 years. The average duration from the onset of encephalitis to the onset of cerebellar symptoms was 30.8 days.The average modified Rankin Scale (mRS) score was 3.73. In the acute phase, the median cerebrospinal fluid leukocyte count was 28×10 6/L. All patients received first-line immunotherapy, of which one case additionally received second-line immunotherapy with rituximab and nine patients received long-term immunotherapy with mycophenolate mofetil. The follow-up time ranged from seven to 66 months. The average mRS score of the last time was 2.73, and only six patients (6/15) had good prognosis (mRS score≤2). Conclusions:Patients with anti-NMDAR encephalitis and cerebellar ataxia are rare, and have relatively poor prognosis in terms of neurological function. Symptoms of cerebellar ataxia in anti-NMDAR encephalitis patients should be recognized in time, and standardized immunotherapy regimens and long-term immunotherapy should be adopted to improve the prognosis.

Cerebellar ataxia mediated by autoimmune mechanisms is a common cause of sporadic cerebellar ataxia. According to the presence of underlining malignancy, autoimmune cerebellar ataxia (ACA) can be divided into paraneoplastic ACA and non-paraneoplastic ACA. The typical manifestations of various types of ACA include gait disorder, limb and trunk ataxia, mild inflammatory response and specific oligoclonal bands in cerebrospinal fluid. Immunosuppressive therapy might be effective. Anti-neuronal antibodies are of great significance to the diagnosis of ACA, and the discovery of the new antibody profile has promoted a deeper understanding of ACA. This article reviews the clinical features and progress of diagnosis and treatment of ACA.

Objective:To analyze the correlation between peripheral blood lymphocyte subsets, especially B cells, and the relapse of autoimmune encephalitis (AE).Methods:A retrospective analysis was conducted on patients with AE who were diagnosed and treated in Peking Union Medical College Hospital from January 2012 to January 2023. The clinical data including gender, age and changes in related indicators of CD19 +B cells, CD16/56 +NK cells, CD3 +T cells, CD4 +T cells, CD8 +T cells, IgG, IgA, and IgM before and after recurrence were analyzed.Binary Logistic regression analysis was applied to the study of correlation between AE recurrence and gender, age, CD19 +B cells, CD16/56 +NK cells, CD3 +T cells, CD4 +T cells, CD8 +T cells, IgG, IgA and IgM. The receiver operating characteristic (ROC) curves of the cells that affect AE recurrence (CD19 +B cells, CD16/56 +NK cells, CD3 +T cells, CD4 +T cells and CD8 +T cells) were plotted separately. Results:A total of 198 eligible AE patients were included, including 98 males and 100 females, aged (39.52±17.91) years. Among these patients, 78 cases had relapses, with a recurrence rate of 39.4%. The results of Logistic regression analysis showed that CD19 +B cells ( B=0.006, P<0.001), CD16/56 +NK cells ( B=0.004, P<0.05), CD3 +T cells ( B=-0.011, P<0.05), CD4 +T cells ( B=0.014, P<0.05) and CD8 +T cells ( B=0.010, P<0.05) were highly correlated with the relapse of AE. ROC curve analysis showed that CD19 +B cells (area under the curve: 0.833, P<0.001, critical value: 73.5/μl; sensitivity: 69.2%, specificity: 86.7%), CD3 +T cells (area under the curve: 0.784, P<0.001), CD4 +T cells (area under the curve: 0.808, P<0.001), and CD8 +T cells (area under the curve: 0.742, P<0.001) all had a certain predictive value for AE relapse. Among all the indicators, the area under the curve of CD19 +B cells was the largest, which had a higher value in predicting AE recurrence. Conclusion:The increase in peripheral blood CD19 +B cells has high predictive value for the relapse of AE.