Clinical prediction rule for neurological sequelae due to acute encephalopathy: a medical community-based validation study in Harima, Japan

Timing of therapeutic interventions against infection-triggered encephalopathy syndrome: a scoping review of the pediatric literature

Our goal was to conduct a scoping review of the literature on the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy in children, focusing on treatment targets and treatment initiation timing. We performed literature searches using PubMed for articles reporting treatments of infection-triggered encephalopathy syndrome/acute encephalopathy. We included articles describing specific treatments for acute encephalopathy with control groups. For the purpose of searching new therapies only experimentally tried in the case series, we also included case series studies without control groups in this review, if the studies contained at least two cases with clear treatment goals. Therapies were classified based on their mechanisms of action into brain protection therapy, immunotherapy, and other therapies. We operationally categorized the timing of treatment initiation as T1 (6-12 h), T2 (12-24 h), T3 (24-48 h), and T4 (>48 h) after the onset of seizures and/or impaired consciousness. Thirty articles were included in this review; no randomized control study was found. Eleven retrospective/historical cohort studies and five case-control studies included control groups with or without specific therapies or outcomes. The targeted conditions and treatment timing varied widely across studies. However, the following three points were suggested to be effective in multiple studies: (1) Careful seizure management and targeted temperature management within 12 h (T1) of onset of febrile seizure/prolonged impaired consciousness without multiple organ failure may reduce the development of acute encephalopathy with biphasic seizures and late reduced diffusion; (2) immunotherapy using corticosteroids, tocilizumab, or plasma exchange within 24 h (T1-T2) of onset of acute necrotizing encephalopathy may reduce sequelae; and (3) anakinra therapy and ketogenic diet demonstrate little evidence of neurologic sequelae reduction, but may reduce seizure frequency and allow for weaning from barbiturates, even when administered weeks (T4) after onset in children with febrile infection-related epilepsy syndrome. Although available studies have no solid evidence in the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy, this scoping review lays the groundwork for future prospective clinical trials.

Neurological prognostic factors for human herpes virus 6/7-associated acute encephalopathy in children: A single-center study

AIM

To identify prognostic factors for severe neurological sequelae and epileptic seizures in children with human herpes virus (HHV) 6/7-associated acute encephalopathy (AE).

METHODS

We retrospectively studied pediatric cases of HHV6/7-associated AE between April 2011 and March 2021. Neurological sequelae were assessed using the Pediatric Cerebral Performance Category scale (PCPC) and the presence of epileptic seizures 1 year after onset. We investigated the prognostic factors between the non-severe sequelae group (PCPC scores ≤ 2) and severe sequelae group (PCPC scores ≥ 3) in patients without severe neurological complications before onset.

RESULTS

Forty patients, ranging from 4 to 95 months old, were included. AE with biphasic seizures and late reduced diffusion were the most common types of encephalopathy (n = 28). Among the 36 patients evaluated neurological sequelae, 17, nine, eight, and two were categorized as PCPC 1, 2, 3 and 4, respectively. Epileptic seizures were observed in nine patients. In the severe sequelae group, significantly more cases with coma in the acute phase and thalamic lesions on MRI and higher serum aspartate aminotransferase, alanine aminotransferase (ALT), and lactate dehydrogenase levels were observed. Multivariate analysis showed a significant between-group difference in the rate of coma (p = 0.0405). Patients with epileptic seizures had a higher rate of coma and thalamic lesions and higher serum ALT and urinary beta 2-microglobulin levels, but there was no significant difference in the multivariate analysis.

CONCLUSIONS

In HHV6/7-associated AE, coma was a significant prognostic factor for severe neurological sequelae.

Clinical and laboratory characteristics of complex febrile seizures in the acute phase: a case-series study in Japan

BACKGROUND

Patients with complex febrile seizures (CFS) often display abnormal laboratory results, unexpectedly prolonged seizures, and/or altered consciousness after admission. However, no standardized values have been established for the clinical and laboratory characteristics of CFS in the acute phase, making the management of CFS challenging. This study aimed to determine the clinical and laboratory characteristics of children with CFS during the acute phase. In particular, the duration of impaired consciousness and the detailed distribution of blood test values were focused.

METHODS

We retrospectively reviewed medical records of a consecutive pediatric cohort aged 6-60 months who were diagnosed with CFS and admitted to Kobe Children's Hospital between October 2002 and March 2017. During the study period, 486 seizure episodes with confirmed CFS were initially reviewed, with 317 seizure episodes included in the analysis. Detailed clinical and laboratory characteristics were summarized.

RESULTS

Among 317 seizure episodes (296 children with CFS), 302 required two or fewer anticonvulsants to be terminated. In 296 episodes showing convulsive seizures, median seizure duration was 30.5 min. The median time from onset to consciousness recovery was 175 min. Impaired consciousness lasting > 6, 8, and 12 h was observed in 13.9%, 7.6%, and 1.9% patients with CFS, respectively. Additionally, the distribution of aspartate aminotransferase, lactate dehydrogenase, creatinine, and glucose were clarified with 3, 10, 50, 90, and 97 percentile values.

CONCLUSION

This study detailed the clinical and laboratory findings of acute-phase CFS using the data of the largest 15-year consecutive cohort of children with CFS. These results provide important information for appropriate acute management of CFS.

Growth and differentiation factor-15 as a potential prognostic biomarker for status-epilepticus-associated-with-fever: A pilot study

OBJECTIVE

Biomarkers predicting poor outcomes of status-epilepticus-associated-with-fever (SEF) at an early stage may contribute to treatment guidance. However, none have been reported thus far. We investigated the dynamics of serum growth and differentiation factor (GDF)-15 after seizure onset in patients with SEF and determined whether GDF-15 can predict poor outcomes, particularly in the first 6 h after seizure onset.

METHODS

We enrolled 37 pediatric patients with SEF and eight patients with simple febrile seizures (SFS) and collected their blood samples within 24 h of seizure onset and eight febrile control patients between March 1, 2017 and September 30, 2020. All patients were aged ≤15 years.

RESULTS

In the SEF group, the median post-seizure serum GDF-15 values were 1,065 (<6h), 2,720 (6-12 h), and 2,411 (12-24 h) pg/mL. The median serum GDF-15 in the first 6 h was measured in patients with SEF without a significant past medical history (n = 21) and was found to be statistically significantly higher (1,587 pg/mL) than in the febrile control (551 pg/mL) and SFS (411 pg/mL) groups. The median serum GDF-15 was statistically significantly higher in patients with SEF with sequelae (n = 5) and patients with acute encephalopathy with biphasic seizures/reduced diffusion/hemorrhagic shock and encephalopathy syndrome (n = 6) than in patients with SEF without sequelae (n = 16) (15,898 vs 756 pg/mL) and patients with prolonged FS (n = 15) (9,448 vs 796 pg/mL).

CONCLUSIONS

This study demonstrates the dynamics of serum GDF-15 in patients with SEF and indicates the potential of GDF-15 as an early predictor of poor outcomes.

Early steroid pulse therapy for children with suspected acute encephalopathy: An observational study

Steroid pulse therapy is widely used to treat virus-associated acute encephalopathy, especially the cytokine storm type; however, its effectiveness remains unknown. We sought to investigate the effectiveness of early steroid pulse therapy for suspected acute encephalopathy in the presence of elevated aspartate aminotransferase (AST) levels.We enrolled children admitted to Hyogo Children's Hospital between 2003 and 2017 with convulsions or impaired consciousness accompanied by fever (temperature >38°C). The inclusion criteria were: refractory status epilepticus or prolonged neurological abnormality or hemiplegia at 6 hours from onset, and AST elevation >90 IU/L within 6 hours of onset. We excluded patients with a neurological history. We compared the prognosis between the groups with or without steroid pulse therapy within 24 hours. A good prognosis was defined as a Pediatric Cerebral Performance Category Scale (PCPC) score of 1-2 at the last evaluation, within 30 months of onset. Moreover, we analyzed the relationship between prognosis and time from onset to steroid pulse therapy.Fifteen patients with acute encephalopathy and 5 patients with febrile seizures were included in this study. Thirteen patients received steroid pulse therapy within 24 hours. There was no between-group difference in the proportion with a good prognosis. There was no significant correlation between PCPC and timing of steroid pulse therapy (rs = 0.253, P = .405). Even after excluding 2 patients with brainstem lesions, no significant correlation between PCPC and steroid pulse therapy timing (rs = 0.583, P = .060) was noted. However, the prognosis tended to be better in patients who received steroid pulse therapy earlier.Steroid pulse therapy within 24 hours did not improve the prognosis in children with suspected acute encephalopathy associated with elevated AST. Still, even earlier administration of treatment could prevent the possible neurological sequelae of this condition.

Early non-convulsive seizures are associated with the development of acute encephalopathy with biphasic seizures and late reduced diffusion

INTRODUCTION

Children with either febrile seizure or acute encephalopathy exhibit seizures and/or impaired consciousness accompanied by fever of unknown etiology (SICF). Among children with SICF, we previously reported those who have refractory status epilepticus or prolonged neurological abnormalities with normal AST levels are at a high risk for the development of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), considered to be caused by excitotoxicity. Non-convulsive seizures (NCS) are common in critically ill children and cause excitotoxic neuronal injury. The aim of this study was to elucidate the prevalence of NCS in the acute phase of children at a high risk for developing AESD and the relationship between NCS in the acute phase and neurological outcomes.

METHODS

We studied 137 children with SICF at a high risk for developing AESD and who underwent continuous electroencephalogram monitoring (cEEG) upon admission to a tertiary pediatric care center at Hyogo Prefectural Kobe Children's Hospital between October 2007 and August 2018. Patient characteristics and outcomes were compared between patients with NCS and without NCS.

RESULTS

Of the 137 children, NCS occurred in 30 children; the first NCS were detected in cEEG at the beginning in 63.3%, during the first hour in 90%, and within 12 h in 96.7%. Neurological sequelae were more common in NCS patients (20.0%) than in non-NCS patients (1.9%; p = 0.001). Five in 30 NCS patients (16.7%) and 3 in 107 non-NCS patients (2.8%) developed AESD (p = 0.013).

CONCLUSION

The occurrence of NCS is associated with subsequent neurological sequelae, especially the development of AESD.

Predicting the outcomes of targeted temperature management for children with seizures and/or impaired consciousness accompanied by fever without known etiology

BACKGROUND

Seizures and/or impaired consciousness accompanied by fever without known etiology (SICF) is common in the pediatric emergency setting. No optimal strategy for the management of SICF in childhood currently exists. We previously demonstrated the effectiveness of targeted temperature management (TTM) against SICF with a high risk of morbidity; however, some patients with SICF develop neurological sequelae despite TTM, which necessitate additional neuroprotective treatment. The clinical characteristics of these severe cases have not been studied. Accordingly, the aim of this study was to identify the clinical characteristics of children with SICF who exhibit poor outcomes after TTM.

METHODS

The medical records of children admitted to Kobe Children's Hospital (Kobe, Japan) between October 2002 and September 2016 were retrospectively reviewed. Patients with SICF treated using TTM were included and divided into the satisfactory and poor outcome groups. Univariate and multivariate logistic regression analyses were used to compare clinical characteristics and laboratory findings between the two groups.

RESULTS

Of the 73 included children, 10 exhibited poor outcomes. Univariate logistic regression analysis revealed that acute circulatory failure before TTM initiation, the use of four or more types of anticonvulsants, methylprednisolone pulse therapy, and an aspartate aminotransferase (AST) level ≥73 IU/L were associated with poor outcomes. Multivariate logistic regression analysis identified an elevated AST level as a significant independent predictor of a poor outcome.

CONCLUSIONS

An elevated AST level within 12 h of onset in children with SICF is an independent predictor of a poor outcome after TTM initiated within 24 h of onset.

Early risk factors for mortality in children with seizure and/or impaired consciousness accompanied by fever without known etiology

BACKGROUND

Children who present with seizure and/or impaired consciousness accompanied by fever without known etiology (SICF) may be diagnosed with either acute encephalopathy (AE) or febrile seizure (FS). Although approximately 5% of AE cases are fatal, it is difficult to identify fatal cases among children with SICF, which are often critical by the time of diagnosis. Thus, early prediction of outcomes for children with SICF, prior to diagnosis, may help to reduce mortality associated with AE. The aim of the present study was to identify clinical and laboratory risk factors for mortality acquired within 6 h of onset among children with SICF.

METHODS

We retrospectively reviewed the medical records of children who had been admitted to Kobe Children's Hospital (Kobe, Japan) with SICF between October 2002 and September 2015. We compared clinical and laboratory characteristics acquired within 6 h of onset and outcomes between survivors and non-survivors using univariate and multivariate analyses.

RESULTS

The survivor and non-survivor groups included 659 and nine patients, respectively. All patients in the non-survivor group received a final diagnosis of AE. Univariate analysis revealed significant differences between the groups with regard to seizure duration and the following laboratory parameters: aspartate transaminase (AST), alanine aminotransferase, lactate dehydrogenase, sodium, and lactate. The multivariate analysis identified AST as a significant independent factor associated with mortality.

CONCLUSIONS

Elevation of AST within 6 h of onset is independently correlated with mortality in children with SICF. Our result may elucidate earlier intervention for patients with high risk of mortality.