No abstract

We read with great interest the study by Lim et al, 1 which aimed to develop an easily applicable scale to grade the severity of autoimmune encephalitis (AE). Nine key clinical features were identified and included in the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). CASE showed good interobserver and intraobserver reliability, and internal consistency, as well as a high correlation with the modified Rankin Scale (mRS).We applied CASE retrospectively to a cohort of 60 patients with AE, admitted to our institution between 2012 and 2018, and prospectively in 3 additional patients. Median age at onset was 55 years (range = 3 months-88 years), in 13 of 63 (21%) onset was before 18 years of age, and 34 of 63 (54%) were female. All patients fulfilled the clinical diagnostic criteria for AE 2 : definite AE was diagnosed in 16 of 63 patients (25%), definite anti-NMDA receptor encephalitis in 11 of 63 (17%), definite autoimmune limbic encephalitis in 6 of 63 (10%), antibody-negative probable AE in 4 of 63 (6 %), possible AE in 25 of 63 (40%), and Hashimoto encephalopathy in 1 of 63 (2%). At the disease nadir, median mRS score was 4 (range = 3-5). We applied CASE at maximum clinical severity (median CASE score = 9, range = 3-24). In our cohort, CASE significantly correlated with mRS (p < 0.0001, r 2 = 0.5025; Fig), although the correlation strength was weaker than that reported by Lim et al. However, we encountered several issues when CASE was applied to our patients that need to be clarified. Severe clinical conditions, such as coma and status epilepticus, make other items hardly assessable (eg, gait instability, language). In such cases, it is not specified what score should be given to items that are not directly assessable (we gave the maximum score). Postictal state after seizures also interferes with the evaluation of most items. The authors should clarify how to apply the scale in these situations and whether this score is meant to be used only in clinically stable patients. Furthermore, when applying CASE to a pediatric population, some items, such as memory and language, were not easily assessable. We think that the scale is more suitable for adult patients. Moreover, it would be appropriate to develop a different scale for patients with altered consciousness.CASE is potentially a useful tool and addresses the unmet need of clinical scales to grade AE severity, as mRS is quite coarse in evaluating this condition. However, CASE needs further improvement and validation to be employed in clinical trials.

This finding suggests that most anti-LGI1 encephalitis develops in a population with specific HLA subtypes, providing insight into a novel disease mechanism. Ann Neurol 2017;81:183-192.

Background and PurposeAnti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most common type of autoimmune synaptic encephalitis and it often responds to treatment. We analyzed the clinical characteristics of anti-NMDAR encephalitis in Korea.MethodsSerum and/or cerebrospinal fluid (CSF) of adult patients (aged ≥18 years) with encephalitis of undetermined cause were screened for anti-NMDAR antibodies using a cell-based indirect immunofluorescence assay. The patients came from 41 university hospitals.ResultsOf the 721 patients screened, 40 were identified with anti-NMDAR antibodies and clinical details of 32 patients were obtained (median age, 41.5 years; 15 females). Twenty-two patients (68.8%) presented with psychiatric symptoms, 16 (50%) with seizures, 13 (40.6%) with movement disorders, 15 (46.9%) with dysautonomia, 11 (34.4%) with memory disturbance, and 11 (34.4%) with speech disturbance. Magnetic resonance imaging, electroencephalography, and CSF examinations yielded nonspecific findings. Tumor information was only available for 22 patients: 5 patients had tumors, and 2 of these patients had ovarian teratomas. Twenty-two patients received immunotherapy and/or surgery, and therapeutic responses were analyzed in 21 patients, of which 14 (66.7%) achieved favorable functional outcomes (score on the modified Rankin Scale of 0-2).ConclusionsThis study investigated the clinical characteristics of adult anti-NMDAR encephalitis in Korea. Currently, elderly patients who do not have tumors are commonly diagnosed with this condition. Understanding the detailed clinical characteristics of this disease will improve the early detection of anti-NMDAR encephalitis in patients both young and old.