Status epilepticus suspected autoimmune: Neuronal surface antibodies and main clinical features.

OBJECTIVES: Status epilepticus (SE) can be associated with neuronal surface antibodies (NS-Abs) but NS-Ab detection rate remains unknown in patients with SE of unclear etiology at symptom presentation but suspected of having an autoimmune etiology (SE suspected autoimmune). We aimed to determine the NS-Ab detection rate and the clinical features that predict the presence of NS-Abs in patients with SE suspected autoimmune. METHODS: We retrospectively reviewed the clinical information of 137 patients with SE suspected autoimmune who underwent testing for NS-Abs between January 2007 and September 2020. NS-Abs were examined in both serum and cerebrospinal fluid (CSF) obtained at symptom onset with established assays. We classified brain magnetic resonance imaging (MRI) findings into unremarkable, autoimmune limbic encephalitis (ALE) (bilateral abnormalities highly restricted to the medial temporal lobes), ALE-Plus (ALE pattern and additional extramedial temporal lobe abnormalities), multifocal cortico-subcortical (MCS), or other pattern. We compared the clinical features between patients with and without NS-Abs. RESULTS: Forty-four patients (32.1%) had NS-Abs, including 35 N-methyl-d-aspartate receptor (NMDAR) (one with concurrent γ-aminobutyric acid B receptor [GABAbR] and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor [AMPAR]), 5 γ-aminobutyric acid A receptor (GABAaR), 2 leucine-rich glioma-inactivated 1(LGI1), 1 GABAbR, and 1 unknown antigens. Compared with NS-Ab-negative patients, NS-Ab-positive patients were more likely to have a preceding headache (56.8% vs 26.7%), preceding psychobehavioral or memory alterations (65.9% vs 20.4%), involuntary movements (79.5% vs 16.1%), CSF pleocytosis (81.8% vs 62.0%), elevated immunoglobulin G (IgG) index (45.2% vs 15.6%), oligoclonal bands (51.5% vs 9.5%), tumor (47.7% vs 8.6%), and higher APE2 score (median of 9 vs 7), and they were less likely to have an ALE-Plus pattern (2.3% vs 23.7%). However, preceding fever and ALE or MCS pattern were not different between the two groups of patients. SIGNIFICANCE: When an autoimmune etiology was suspected, there was a relatively high likelihood (one of three patients) of identifying NS-Abs. Some clinical features (preceding symptoms, inflammatory CSF) predict a higher likelihood of finding NS-Ab positivity, but the ALE-Plus MRI pattern is more likely suggestive of NS-Ab negativity.

Clinically based score predicting cryptogenic NORSE at the early stage of status epilepticus.

OBJECTIVE: To determine whether a clinically based score predicts cryptogenic new-onset refractory status epilepticus (C-NORSE) at the early stage of status epilepticus (SE) with prominent motor symptoms (SE-M) of unclear etiology. METHODS: The score (range 0-6) included 6 clinical features: highly refractoriness to antiseizure drugs, previously healthy individual, presence of prodromal fever, absence of prodromal psychobehavioral or memory alterations, absence of dyskinesias, and symmetric brain MRI abnormalities (the first 2 mandatory). We retrospectively assessed the usefulness of a high scale score (≥5) in predicting C-NORSE in 83 patients with SE-M of unclear etiology, who underwent testing for neuronal surface antibodies (NS-Abs) between January 2007, and December 2019. RESULTS: Thirty-one (37.3%) patients had a high score. Patients with a high score had more frequent prodromal fever (28/31 vs 24/52), mechanical ventilatory support (31/31 vs 36/52), and symmetric MRI abnormalities (26/31 vs 12/52), had less frequent involuntary movements (2/31 vs 30/52), and had absent prodromal psychobehavioral alterations (0/31 vs 27/52), CSF oligoclonal band detection (0/27 vs 11/38), tumor association (0/31 vs 13/52), or NS-Abs (0/31 vs 29/52) than those with a low score (<5). Thirty-three patients (median age, 27 years; 18 [54.5%] female) were finally regarded as C-NORSE. The sensitivity and specificity of a high score for predicting C-NORSE were 93.9% (95% CI 0.87-0.94) and 100% (95% CI 0.95-1.00), respectively. CONCLUSIONS: Patients with a high score in the indicated scale are more likely to have C-NORSE, making it a useful diagnostic tool at the early stage of SE-M before antibody test results become available.

Correction to: A cluster of disseminated small cortical lesions in MELAS: its distinctive clinical and neuroimaging features.

The author would like to correct the errors in the publication of the original article. The corrected details are given below for your reading.

A cluster of disseminated small cortical lesions in MELAS: its distinctive clinical and neuroimaging features.

OBJECTIVES: To investigate a diversity of stroke-like episodes (SLEs) in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), and report a disseminated form of SLEs (D-SLEs) attributed to a cluster of disseminated small cortical lesions. METHODS: We retrospectively reviewed the clinical information of 27 MELAS patients seen at Kitasato University Hospital between January 1990 and April 2018. Among those, we selected 13 patients with m.3243A>G mutation [median age at onset, 35 years (11-68 years), two pediatric onset < 17 years] who had at least one SLE. SLEs were classified into classic or non-classic based on characteristic features of stroke-like lesions. RESULTS: 44 SLEs were identified during a median observational period of 119 months (3-240 months). Among those, 29 (65.9%) were classic SLEs (C-SLEs) mainly attributed to a single continuous lobular lesion incongruent to vascular territory and occasionally accompanied by a gradual spread associated with hyperperfusion and persistent seizure activity. The remaining 15 were non-classic attributed to sparsely distributed (n = 10), disseminated (n = 4) or cerebellar lesions (n = 1). C-SLEs developed in all patients but non-classic SLEs in 5; D-SLEs developed in 4 patients accounting for 4 of 44 SLEs (9.1%). Non-classic SLEs developed more frequently in pediatric-onset than in adult-onset patients (12/15 vs. 3/29, p < 0.0001). SLEs began with acute onset of symptoms in 42 SLEs (95.5%), but D-SLEs of 2 adult-onset patients began with ill-defined subacute-onset fluctuating encephalopathy. CONCLUSIONS: This study showed a diversity of SLEs in patients with m.3243A>G mutation. Further studies are required to elucidate the pathophysiological mechanisms of non-classic SLEs including D-SLEs.

Evoked potential studies for predicting functional recovery in a case of acute necrotizing encephalopathy.

Normal-appearing evoked potentials during the acute stage of the disease despite persistent coma may predict subsequent functional recovery of the brain in a pediatric case of acute necrotizing encephalopathy, indicating that evoked potential studies are useful for predicting functional outcome of the brain.

Cryptogenic NORSE: Its distinctive clinical features and response to immunotherapy.

OBJECTIVE: To report the distinctive clinical features of cryptogenic new-onset refractory status epilepticus (C-NORSE) and the C-NORSE score based on initial clinical assessments. METHODS: A retrospective study was conducted for 136 patients with clinically suspected autoimmune encephalitis who underwent testing for autoantibodies to neuronal surface antigens between January 1, 2007, and August 31, 2016. Eleven patients with C-NORSE were identified. Their clinical features were compared with those of 32 patients with anti-NMDA receptor encephalitis (NMDARE). RESULTS: The clinical outcome of 11 patients (median age, 27 years; 7 [64%] women) with C-NORSE was evaluated after a median follow-up of 11 months (range, 6-111 months). Status epilepticus was frequently preceded by fever (10/11 [91%]). Brain MRIs showed symmetric T2/fluid-attenuated inversion recovery hyperintensities (8/11 [73%]) and brain atrophy (9/11 [82%]). Only 2 of the 10 treated patients responded to the first-line immunotherapy, and 4 of the 5 patients treated with IV cyclophosphamide responded to the therapy. The long-term outcome was poor in 8 patients (73%). Compared with 32 patients with NMDARE (median age, 27 years; 24 [75%] women), those with C-NORSE had more frequent prodromal fever, status epilepticus, ventilatory support, and symmetric brain MRI abnormalities, had less frequent involuntary movements, absent psychobehavioral symptoms, CSF oligoclonal bands, or tumor association, and had a worse outcome. The C-NORSE score was higher in patients with C-NORSE than those with NMDARE. CONCLUSIONS: Patients with C-NORSE have a spectrum of clinical-immunological features different from those with NMDARE. The C-NORSE score may be useful for discrimination between them. Some patients could respond to immunotherapy.

No Relationships between Psychosis and the Diazepam Binding Inhibitor rs2276596 (C/A) Polymorphism in Japanese: An Exploratory Study.

OBJECTIVE: Our recent study for the first time reported genotyping method of the diazepam binding inhibitor (DBI) rs2276596 polymorphism using a Polymerase Chain Reaction-Restriction Fragment Length Polymor- phism (PCR-RFLP), and revealed a significant relationships between this polymorphism and alcohol depend- ence. In this study, to facilitate elucidation of the pathogeneses of psychoses including schizophrenia and mood (affective) disorders, we investigated the relationship between the DBI rs2276596 polymorphism (C/A) and psychoses. METHOD: We analyzed the DBI genotypes using the PCR-RFLP method in healthy controls, and psychotics including schizophrenia and mood (affective) disorders (including recurrent depressive disorder and bipolar affective disorder) (ICD-10: F31, F33). RESULT: There was no significant difference in the rs2276596 genotype and allele frequencies of the DBI gene between these psychoses and healthy controls. CONCLUSION: The present data suggested that a mutated allele of the DBI was not one of the risk factors for schizophrenia and mood (affective) disorders, as for the rs2276596 polymorphism. [Original].

[Intraoperative ABR Monitoring in Neurosurgery].

Monitoring of the intraoperative auditory brainstem response (ABR) is a less invasive, easy, and useful method for hearing preservation in patient undergoing cerebellopontine angle surgery such as microvascular decompression (MVD) and excision of an acoustic neurinoma. The ABR is tolerant of both inhalation and intravenous anesthesia. However, ABR recordings are highly susceptible to electrical noise from surgical devices. Therefore, for ABR recordings to be reliable, noise must be minimized and appropriate evaluation of waveform changes is critical. Electrode setting with low contact impedance and bilateral derivation effectively address these issues. Prolongation of the wave V latency alerts to surgical stress on the cochlear nerve due to nerve stretching from cerebellar retraction. According to Sekiya, the surgeon performing MVD or acoustic neurinoma excision should be warned as soon as latency prolongation exceeds 1.5 msec or characteristics of ABR must be understood. even less than 0.5 msec, respectively. However, hearing was preserved in some patients with false-positive results with respect to intraoperative wave V diminution. To use it as a useful intraoperative modality, the Characteristics of ABR must be understood.

[Electroencephalographic background activity and blood biochemistry data in patients with chronic renal failure during chronic hemodialysis].

There is no particular electroencephalographic activity known to be associated with consciousness disturbance in uremic patients; however, a slow wave activity is generally observed during consciousness disturbance. Abnormal electroencephalographic activity was observed in 30 (67%) of 45 chronic renal failure patients during chronic hemodialysis without consciousness disturbance, and slow wave activity was observed in 58%. The frequency of the electroencephalographic background activity correlated with blood urea nitrogen (BUN) and serum Ca levels, but not with K, IP, and creatinine levels. Electroencephalographic activity can be estimated with reference to BUN or serum Ca levels in the blood of uremic patients.

[Electroencephalographic examination in alcohol dependents].

It has been reported that electroencephalographic (EEG) examinations of alcohol dependents reveal a few abnormal findings. However, we show abnormal findings in 47 (64%) of 73 alcohol dependents in whom disturbance of consciousness, convulsions, disturbance of memory, emotional disorders and hallucination were present. Our results indicate that EEG examination may be necessary for real time assessment of brain function in alcoholism.

Neurophysiological mechanisms of conduction impairment of the auditory nerve during cerebellopontine angle surgery.

OBJECTIVE: Intraoperative auditory brainstem response (ABR)-monitoring is useful for hearing preservation in patients undergoing cerebellopontine angle surgery. Prolongation of the latency of wave V, for example, is observed under surgical stress such as cerebellar retraction. We analyzed intraoperative ABR findings to study the neurophysiological mechanism(s) underlying latency prolongation. METHODS: The ABR recorded during microvascular decompression surgery was studied in 18 patients with hemifacial spasm. We measured each trace of the ABR records, both the latency of each wave and some interpeak latencies. We also analyzed their waveforms especially in the early component, to assess changes during surgery. RESULTS: The latency of wave V varied with cerebellar retraction. The delayed latency of wave V was correlated with the prolonged interpeak latency of waves I-III. An additional wave (designated wave I') between waves I and II was appeared; it was accompanied by a prolongation in the latency of wave V. Wave I' contributed to prolongation of the interpeak latency of waves I-III, resulting in a delay in the latency of wave V. Chronological analysis revealed that the minimum latency of wave I' was the same as wave IN, suggesting that wave I' arose near the porus acusticus internus (PAI). CONCLUSION: Our study showed that cerebellar retraction may result in conduction impairment of the auditory nerve near the PAI, suggesting that the Obersteiner-Redlich zone is an electrophysiologically vulnerable site and wave I' is derived from the change in the vector of wave IN. SIGNIFICANCE: Our findings may provide neurophysiological evidence to support the theoretical model of ABR generators by Scherg and von Cramon.