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

Time course of serum cytokine level changes within 72 h after onset in children with acute encephalopathy and febrile seizures

BACKGROUND

Cytokine levels have been measured in acute encephalopathy (AE) to determine its pathology or as a diagnostic biomarker to distinguish it from febrile seizures (FS); however, the dynamics of cytokine level changes have not yet been fully captured in these two neurological manifestations. Thus, we aimed to explore the time course of serum cytokine level changes within 72 h after onset in AE and FS.

METHODS

We retrospectively measured cytokine level in residual serum samples at multiple timepoints in seven children whose final diagnoses were AE or FS.

RESULTS

The levels of 13 cytokines appeared to increase immediately after onset and peaked within 12-24 h after onset: interleukin (IL)-1β, IL-4 IL-5, IL-6, IL-8, IL-10, IL-17, eotaxin, fibroblast growth factor, granulocyte colony-stimulating factor, interferon gamma, interferon-inducible protein-10, and macrophage chemoattractant protein-1. There were no dynamic changes in the levels of three cytokines (IL-1 receptor agonist, macrophage inflammatory protein-1α, and platelet-derived growth factor-bb) 72 h after onset. Levels of some cytokines decreased to around control levels within 48 h after onset: IL-1β, IL-4, IL-5, IL-17, fibroblast growth factor, and interferon gamma. The levels of most cytokines appeared to be higher in AE, especially in hemorrhagic shock encephalopathy syndrome, than in FS.

CONCLUSIONS

Cytokine levels in both AE and FS change dynamically, such as the levels of several cytokines increased within a few hours after onset and decreased at 12-24 h after onset. Therefore, it will be desirable to make clinical decisions regarding the administration of anti-inflammatory therapy in 24 h after onset in AE.

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.

Detailed clinical course of fatal acute encephalopathy in children

OBJECTIVE

Although the mortality among previously healthy children with acute encephalopathy (AE) is approximately 5%, their detailed clinical course has not been clarified. The objective of the present study was to describe the detailed clinical course, in minutes, of fatal AE.

METHODS

We retrospectively reviewed the medical records of five patients (from 6 months to 14 years of age) who previously had no neurological disorders and were diagnosed with brain death due to AE between 2002 and 2018 at Kobe Children's Hospital.

RESULTS

The initial clinical symptoms were convulsion in three cases and impaired consciousness in two. The earliest noted brain imaging abnormality was 7.5 h after neurological symptom detection. Liver enzymes and creatinine levels increased at initial examination, and sodium elevated gradually. All patients met the criteria of systemic inflammatory response syndrome, disseminated intravascular coagulation, and shock within 14 h of symptom detection. High dose steroids and targeted temperature management were initiated 3.5-14 h after onset. Despite these therapies, patients were diagnosed with brain death from 16 h to 4 days after initial neurological symptoms. AE diagnoses were made between 4 h 29 min and 4 days after initial neurological symptoms and included hemorrhagic shock and encephalopathy syndromes, Reye-like syndrome, and acute necrotizing encephalopathy in two, two, and one patient(s), respectively.

CONCLUSIONS

We revealed the time series' of clinical events (e.g. SIRS, shock, DIC, AE diagnosis, brain death, and treatments) and laboratory findings relative to initial neurological symptom in fatal AE.

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.