[Acute non-herpetic encephalitides].

"Acute non-herpetic encephalitis" was consisted of several non-herpetic encephalitides including "acute juvenile female non-herpetic encephalitis (AJFNHE)" and "non-herpetic limbic encephalitis(NHLE)". In 1997, we first reported five young adult female patients with acute non-herpetic encephalitis who presented with severe prolonged coma and status epilepticus, but achieved a good recovery. Following this report, the results of a clinical analysis on 89 serial patients with encephalitides indicated that such patients presented specific and different clinical features, including the frequent detection of anti-glutamate receptor (GluR) antibody as compared with other etiologies of encephalitis. Since all of their 11 patients were young adult women, we designated these patients as "acute juvenile female non-herpetic encephalitis (AJFNHE)". In 2007, Dalmau et al. reported anti-N-methyl-D-aspartate receptor(NMDAR) encephalitis associated with ovarian teratoma. We recently reported the results of a nationwide survey on AJFNHE in Japan. This result was indicated that AJFNHE and anti-NMDAR encephalitis were inferred to be almost identical condition. AJFNHE thus represented a clinical concept based on the specific clinical features, and anti-NMDAR encephalitis represented a clinical entity based on the neuro-oncological findings including the NMDAR NR1 and NR2 heteromer antibody.

Nationwide survey of acute juvenile female non-herpetic encephalitis in Japan: relationship to anti-N-methyl-D-aspartate receptor encephalitis.

OBJECTIVE: To study the incidence and clinical features of acute juvenile female non-herpetic encephalitis (AJFNHE) in Japan. METHODS: A nationwide questionnaire on patients with severe non-herpetic encephalitis of unknown etiology with a prolonged clinical course or death was sent to the departments of Internal Medicine, Neurology, Pediatrics, and Emergency and Critical Care at all hospitals with 200 beds or more in Japan. RESULTS: The recovery rate was 25% (1,279 out of 5,030 departments) and 90 patients were enrolled in this study. The annual incidence was 0.33/10(6) population. 85% of patients were female. The means and standard deviations of age at onset and hospital stay were 26+/-10 years and 180+/-228 days. As first symptoms, fever and psychosis were presented in 90%. Among the neurological symptoms, disturbance of consciousness was presented in 92%, convulsions in 65%, and involuntary movements in 55%. Respiratory failure during hospitalization was observed in 71% and required care with mechanical ventilation. The detection rate of anti-GluR epsilon2 and/or delta1 antibodies was 67% of patients. Anti-N-methyl-D-aspartate receptor NR1/NR2 antibody was detected in all four examined patients with anti-GluR epsilon2 antibody, and also detected in both of the two examined patients without anti-GluR epsilon2 antibody. As for outcome, 46% returned to work and 37% returned home, but 7% died. Associated tumors were demonstrated in 39%. All reported patients had ovarian tumors, among which teratoma was the most frequent. CONCLUSION: A nationwide survey provided data for the annual incidence and clinical features of AJFNHE in Japan.

Prognostic value of cerebrospinal fluid cytokine changes in herpes simplex virus encephalitis.

A recent trial suggested that corticosteroid was beneficial in herpes simplex virus encephalitis (HSVE), but that precise role remains unclear. We assessed the differences of cerebrospinal fluid (CSF) cytokine changes between different outcomes and between patients with and without corticosteroid administration at the acute stage of HSVE. Interleukin (IL)-1beta, IL-2, IL-6, IL-10, interferon (IFN)-gamma, and tumor necrosis factor-alpha were measured in 56 serial CSFs taken from 20 adult HSVE patients. Their outcomes were poor in 7 and good in 13 patients, and corticosteroid was administered in 10. The differences in the initial and maximum cytokine values were assessed among the different outcomes. The decline rate of cytokine values between the initial and second CSF samples was also assessed between patients with and without corticosteroid. The initial IFN-gamma and maximum IL-6 with a poor outcome were higher than those with a good outcome (p=0.019 for IFN-gamma and p=0.013 for IL-6). The decline rate of IL-6 in patients with corticosteroid was higher than that without corticosteroid (p=0.034). The initial IFN-gamma and maximum IL-6 CSF values represented prognostic biomarkers in HSVE. One pharmacological mechanism related to corticosteroid in HSVE is apparently inhibition of pro-inflammatory cytokines such as IL-6.

Hospital-based study of the prognostic factors in adult patients with acute community-acquired bacterial meningitis in Tokyo, Japan.

BACKGROUND: Prognostic factors related to community-acquired bacterial meningitis (BM) in adult patients have been evaluated using multivariate analysis in The Netherlands, where the rate of antibiotic resistance was low. However, an evaluation of these factors in countries with a high rate of antibiotic resistance has not yet been done. Thus, we studied the prognostic factors in adults with community-acquired BM in our hospitals, which are located in Tokyo, Japan, where the rate of antibiotic resistance is high. METHODS: We selected 71 consecutive adult patients with community-acquired BM in which the pathogens were identified and then classified the patients into two groups based on the Glasgow Outcome Scale: a favorable outcome group (n=48), and an unfavorable outcome group (n=23). Their clinical and laboratory variables were analyzed using single logistic regression analysis followed by multiple logistic regression analysis. RESULTS: The overall mortality rate was 23%. The rate of antibiotic resistance was 54.9%. The most common resistant bacteria were penicillin-resistant Streptococcus pneumoniae, followed by methicillin-resistant Staphylococcus aureus. The Glasgow Coma Scale score (GCS) at the initiation of antibiotic therapy and a low thrombocyte count were identified as significant unfavorable prognostic factors (GCS: p=0.020, odds ratio=0.528, 95%CI=0.309-0.902; thrombocyte count: p=0.037, odds ratio=0.802, 95%CI=0.652-0.987). The presence of antibiotic-resistant bacteria was not identified as a prognostic factor. CONCLUSION: Patients with a low GCS at the initiation of antibiotic therapy and low thrombocyte counts had unfavorable outcomes. With appropriate antibiotic administration, the antibiotic-resistant bacteria were not identified as an unfavorable prognostic factor, even in an area with a high rate of antibiotic resistance.

Predictors of a prolonged clinical course in adult patients with herpes simplex virus encephalitis.

OBJECTIVE: Herpes simplex virus encephalitis (HSVE) patients occasionally follow a prolonged course despite standard antiviral treatment. The purpose of this study was to analyze clinical variables to identify predictors of a prolonged course. METHODS: A series of 23 HSVE patients treated with acyclovir (ACV) during the acute stage were selected and divided into 2 groups: the non-prolonged group (n = 15), with improvement within 2 weeks after initial ACV treatment; and the prolonged group (n = 8), without improvement within 2 weeks. Differences in clinical variables, including age, duration from onset to initial ACV treatment, Glasgow coma scale (GCS) score, corticosteroid administration, detection of abnormal lesions on initial cranial computed tomography (CT) and magnetic resonance imaging, detection of periodic lateralized epileptiform discharges on electroencephalogram, and clinical outcome, were compared between the groups. RESULTS: There were significant differences in GCS score, clinical outcome, and detection of lesions on CT between the non-prolonged and prolonged groups [p = 0.021, p = 0.041 (Mann-Whitney's U test), respectively, and p = 0.027 (Fisher's exact test)]. Four of the eight patients with a prolonged course had a poor outcome despite treatment with additional drugs. CONCLUSION: A lower GCS and a higher rate of lesions on CT were identified as predictors of a prolonged course for HSVE. These predictors are in accordance with the conventional predictors of poor outcome for HSVE. This study suggests that the initial ACV treatment was insufficient for HSVE patients with these predictors at the acute stage. The initial treatment may need to be modified for such patients.