Determinants of outcomes for acute encephalopathy with reduced subcortical diffusion

Arterial spin labeling image findings in the acute phase in paediatric patients with acute encephalopathy with biphasic seizures and late reduced diffusion

Introduction

Diagnosing acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) after the first seizure (early seizure/seizures, ES/ESs) is challenging because a reduced apparent diffusion coefficient (ADC) in the cortical or subcortical white matter, often described as having a "bright-tree appearance (BTA)," is usually not observed until secondary seizures (late seizures, LSs) occur. Previous studies have reported hypoperfusion on arterial spin labeling (ASL) within 24 h after ES/ESs in patients with AESD and hyperperfusion within 24 h after LS onset. This study aimed to investigate cerebral blood flow in the hyperacute phase (between ES/ESs and LSs) using ASL in patients with AESD.

Methods

Eight ASL images were acquired in six patients with AESD admitted to our hospital from October 2021 to October 2022. ASL findings in the hyperacute phase were investigated and video-electroencephalogram findings obtained around ASL image acquisition in the hyperacute phase were evaluated.

Results

Four ASL images were obtained for three patients before LS onset, with three images showing hyperperfusion areas and one image showing hypoperfusion areas. These hyperperfuion regions coincided with BTA on subsequent images of these patients.In one patient, the first ASL image was obtained in the late hyperacute phase and revealed hyperperfusion areas with a slightly abnormal change on diffusion-weighted image (DWI), which were not accompanied by ADC abnormalities. The second ASL image obtained 51 h after the first ASL, and before LS onset revealed more prominent hyperperfusion areas than the first ASL image, which were accompanied by BTA. In another patient, the ASL image obtained 82 h after ES revealed hyperperfusion areas without abnormal change on DWI or ADC.

Conclusion

This study revealed that two patients exhibited hyperperfusion regions and another patient exhibited hypoperfusion regions among three patients who underwent ASL imaging during the period from 24 h after ES/ESs to LSs in patients with LSs or cooling initiation in patients without LSs due to early anaesthesia induction (late hyperacute phase). Further prospective studies on cerebral blood flow are required to explore the relationship among the timing of image acquisition, the presence of electrographic seizures, and ASL findings in patients with AESD.

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.

Brain Hypothermia Therapy and Targeted Temperature Management for Acute Encephalopathy in Children: Status and Prospects

In adult intensive care, brain hypothermia therapy (BHT) was reported to be effective in neuroprotection after resuscitation and cardiac arrest. By contrast, in neonatal intensive care, the pathophysiology of brain damage caused by hypoxic–ischemic encephalopathy (HIE) is attributed to circulatory disturbances resulting from ischemia/reperfusion, for which neonatal brain cryotherapy is used. The International Liaison Committee on Resuscitation, 2010, recommends cerebral cryotherapy for HIE associated with severe neonatal pseudoparenchyma death. The usefulness of BHT for neuroprotection in infants and children, especially in pediatric acute encephalopathy, is expected. Theoretically, BHT could be useful in basic medical science and animal experiments. However, there are limitations in clinical planning for treating pediatric acute encephalopathy. No international collaborative study has been conducted, and no clinical evidence exists for neuroprotection using BHT. In this review, we will discuss the pathogenesis of neuronal damage in hypoxic and hypoperfused brains; the history of BHT, its effects, and mechanisms of action; the success of BHT; cooling and monitoring methods of BHT; adverse reactions to BHT; literature on BHT. We will review the latest literature on targeted temperature management, which is used for maintaining and controlling body temperature in adults in intensive care. Finally, we will discuss the development of BHT and targeted temperature management as treatments for pediatric acute encephalopathy.

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.

Involuntary movements as a prognostic factor for acute encephalopathy with biphasic seizures and late reduced diffusion

BACKGROUND

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is characterized by biphasic seizures and white matter lesions with reduced diffusion, which are often accompanied by involuntary movements. The neurological outcomes of AESD vary from normal to mild or severe sequelae, including intellectual disability, paralysis, and epilepsy. The present study aimed to clarify the prognostic factors of AESD, including involuntary movements.

METHODS

We enrolled 29 patients with AESD admitted to Tottori University Hospital from 1991 to 2020 and retrospectively analyzed their clinical data. Neurological outcomes were assessed by the Pediatric Cerebral Performance Category score and cerebral paralysis as neurological sequelae.

RESULTS

Of the 29 patients, 12 had favorable outcomes and 17 had unfavorable outcomes. Univariate analysis revealed that the presence of underlying diseases, a decline in Glasgow Coma Scale (GCS) score 12-24 h after early seizures, and involuntary movements were associated with unfavorable outcomes. In multivariate analysis, a decline in GCS score and involuntary movements were associated with unfavorable outcomes. The sensitivities and specificities of underlying diseases, a decline of ≥ 3 points in GCS score 12-24 h after early seizures, and involuntary movements for unfavorable outcomes were 53% and 92%, 92% and 65%, and 59% and 92%, respectively.

CONCLUSIONS

The appearance of involuntary movements may be associated with unfavorable outcomes of AESD. The prognostic factors identified herein are comparable with previously known prognostic factors of consciousness disturbances after early seizures.

Predicting the Onset of Acute Encephalopathy With Biphasic Seizures and Late Reduced Diffusion by Using Early Laboratory Data

Background: Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) often causes various neurological sequelae, necessitating early and objective differentiation of AESD from a febrile seizure (FS). Therefore, we developed a scoring system that predicts AESD onset using only early laboratory data. Methods: We selected patients with AESD or FS admitted to the Tottori University Hospital between November 2005 and September 2020 and collected laboratory data from onset to discharge in patients with FS and from onset to the second neurological events in patients with AESD. Results: We identified 18 patients with AESD and 181 patients with FS. In comparison with patients with FS, patients with AESD showed statistically significant increases in ammonia (NH3), blood sugar (BS), and serum creatinine (Cr) levels, and the white blood cell (WBC) count, and a significant decrease in pH at <3 h from onset. We set the cut-off values and adjusted the weight of each of these parameters based on data obtained <3 h from onset and proposed a scoring system for predicting AESD. This system showed 91% sensitivity and 94% specificity for distinguishing AESD from FS. These accuracies were only slightly improved by the addition of information related to consciousness and seizure duration (sensitivity, 91%; specificity, 96%). Conclusion: NH3, BS, and Cr levels, WBC count, and pH were significantly different between patients with AESD and patients with FS at <3 h from seizure onset. This scoring system using these data may enable the prediction of AESD onset for patients under sedation or without precise clinical information.

Truncal Instability and Titubation in Patients With Acute Encephalopathy With Reduced Subcortical Diffusion

The present retrospective study aimed to investigate the presence of truncal instability or titubation after the first seizure and second phase in patients with acute encephalopathy with reduced subcortical diffusion (AED). Of the 15 patients with AED who were admitted to our hospital for 3 years and 2 months and had reached developmental milestones for sitting before disease onset, six experienced moderate-to-severe truncal instability while sitting after the first seizure. These patients had a significantly longer first seizure duration and significantly lower GCS scores 12-24 h after the first seizure, as well as significantly higher Tada score and Creatinine and blood glucose levels than those with mild or no truncal instability while in a seated position after the first seizure. Three 1-year-old children with bilateral frontal lobe lesions, particularly in the bilateral prefrontal lobe regions, demonstrated truncal titubation, which has not previously been reported as a clinical feature of AED. Tada score reported to be a predictor of AED prognosis and truncal instability in the sitting position after the first seizure may represent disease severity, but not the specific lesions. Conversely, truncal titubation might be suggestive of bilateral frontal lobe lesions, particularly in patients without severe instability. Further studies on the role of bilateral prefrontal lobe lesions to truncal titubation in patients with AED using more objective evaluation methods, such as stabilometry, are necessary.

The spectrum of acute leukoencephalopathy with restricted diffusion (ALERD): A case series and review of literature

INTRODUCTION

The clinico-etiological spectrum of Acute leukoencephalopathy with restricted diffusion (ALERD) is not well known in Indian population. This is likely to vary between populations and ethnicities.

METHODS

We retrospectively reviewed the clinicoetiological spectrum of ALERD at a tertiary care pediatric center, and described the clinical, imaging, etiological spectrum and short-term outcomes.

RESULTS

Eleven out of 78 children with non-traumatic encephalopathy presenting to our center had a final diagnosis of ALERD. The mean age at presentation was 34.9 months (6-80 months) and 63.6% were males. The monophasic course (72.7%) and the diffuse pattern (63.6%) on neuroimaging were predominant in these children. Dengue haemorrhagic fever was the commonest underlying/triggering infection (5 of 11 children). Ten children required mechanical ventilation in view of neurogenic respiratory failure, with mean duration of ventilation of 6.4 days (Range 2-10 days). The duration of hospital stay varied from 11 to 25 days (Mean - 15.3 days). One child (9 %) died, 6 children (54.5 %) had varying degrees of cognitive impairment and 4 (36.3 %) children had a normal outcome. Children with a shorter duration of ventilation seemed to have a better outcome.

CONCLUSION

Dengue haemorrhagic fever was the commonest cause, and diffuse imaging pattern with monophasic course was the commonest presentation in Indian children with ALERD. The clinical presentation and factors influencing outcome are possibly different from previously described literature.