Hepatic Encephalopathy in Children With Acute Liver Failure: Utility of Serum Neuromarkers

Theta-Alpha Variability on EEG Is Associated With Acute Brain Injury in Children and Young Adults With Liver Failure

Background and Objectives

Patients with liver failure experience long hospitalizations and acute neurologic complications. Encephalopathy limits the bedside examination, rendering presenting signs of acute brain injury less specific. Seizures are common. Brain MRI is the gold standard for detecting acute brain injury, but intensive medical needs may preclude immediate transfer for imaging. EEG is a bedside test applied in cases of seizure or encephalopathy. We hypothesized that EEG variables can predict MRI signs of acute brain injury in children hospitalized with liver failure.

Methods

In this retrospective cohort analysis, records were collected for patients admitted to a MedStar hospital between 2014 and 2022 with ICD-9/10 codes related to liver failure, who underwent brain MRI and EEG testing during the same admission. Exclusion criteria included age older than 24 years and >7 days elapsing between EEG and MRI testing. Clinical data of interest from chart review, reinterpreted MRI scans, reinterpreted EEG tracings, and quantitative EEG variables were compiled into a database. Quantitative EEG variables were processed using MNE-Python.

Results

Of 746 records screened, 52 patients met inclusion criteria comprising 63 EEG-MRI pairs. Univariate analysis of all quantitative EEG variables of interest showed depressed theta-alpha variability (TAV) when paired MRI involved abnormal restricted diffusivity in cortical or deep gray matter structures (TAV 0.705, SD 0.310; p < 0.001) compared with MRI with no abnormal restricted diffusivity (TAV 0.895, SD 0.095). Multilinear regression analysis including potential confounders demonstrated independent association of depressed TAV with this MRI finding, with an odds ratio of 4.0317 (95% CI 1.3868-11.7165; AUROC 0.83).

Discussion

Depressed TAV on EEG is associated with increased odds of abnormal restricted diffusivity in gray matter on brain MRI in children and young adults hospitalized with liver failure. This MRI finding is seen in scenarios where changes to medical management are time-sensitive (i.e., acute stroke and PRES) or where prognostic discussion may be influenced by MRI findings (hypoxic-ischemic injury). TAV thus has a potential role as an automated, bedside decision support tool for clinicians deciding on the urgency of brain MRI in critically ill patients.

Hepatic Encephalopathy in Children

Hepatic encephalopathy, characterized by mental status changes and neuropsychiatric impairment, is associated with chronic liver disease as well as acute liver failure. In children, its clinical manifestations can be challenging to pinpoint. However, careful assessment for the development of hepatic encephalopathy is imperative when caring for these patients as progression of symptoms can indicate impending cerebral edema and systemic deterioration. Hepatic encephalopathy can present with hyperammonemia, but it is important to note that the degree of hyperammonemia is not indicative of severity of clinical manifestations. Newer forms of assessment are undergoing further research, and include imaging, EEG and neurobiomarkers. Mainstay of treatment currently includes management of underlying cause of liver disease, as well as reduction of hyperammonemia with either enteral medications such as lactulose and rifaximin, or even with extracorporeal liver support modalities.

[Advancements in the diagnosis and treatment of pediatric acute liver failure]

Pediatric acute liver failure (PALF) is a rare and rapidly progressive clinical syndrome with a poor prognosis and significant mortality. The etiology of PALF is complex, and it presents with diverse and atypical clinical manifestations. Accurate diagnosis based on age-related factors, early recognition or prevention of hepatic encephalopathy, and precise supportive treatment targeting the underlying cause are crucial for improving outcomes and prognosis. This article provides a comprehensive review of recent research on the diagnosis and treatment of PALF, aiming to offer guidance for clinical practice.

Novel Serum Biomarkers Associated With Pediatric Hepatic Encephalopathy: A Systematic Review

BACKGROUND

The pathophysiology of pediatric hepatic encephalopathy (HE) is not well understood. Various serum biomarkers associated with HE may provide insight into its pathology, but their use and interpretation in clinical practice for diagnosis and prognostication remain undetermined. We sought to investigate reported correlations of serum biomarkers with presence and degree of HE in children.

METHODS

We conducted a systematic review of studies examining novel serum biomarkers and cytokines in association with HE that included children on PubMed, Embase, Lilacs, and Scopus. We utilized Covidence for abstract and text review by 2 independent reviewers for each study.

RESULTS

We reviewed 2824 unique publications; 15 met criteria for inclusion. Categories of biomarkers reported were inflammatory cytokines, products of amino acid metabolism, trace elements and vitamins, and hepatic and neuro biomarkers. Of 19 individual biomarkers, only 5 were measured in more than 1 study. Elevations in interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were most commonly reported as associated with HE. Notably, we observed lower average IL-6 and TNF-alpha levels in pediatric-only studies compared to mixed age studies. Overall, high bias and poor applicability to our review question was observed. We encountered low numbers of studies with pediatric focus, and few conducted with low bias study designs.

CONCLUSION

Investigated biomarkers span a large range of categories and suggest potentially useful correlations with HE. Further well-designed prospective biomarker research is necessary to better elucidate the pathogenesis of HE in children and improve early detection and clinical care.

Combination of Plasma Exchange and Adsorption Versus Plasma Exchange in Pediatric Acute Liver Failure: A Multicenter Cohort Study

OBJECTIVES

This study aimed to compare the efficacy of double plasma molecular adsorption system (DPMAS) with half-dose plasma exchange (PE) to that of full-dose PE in pediatric acute liver failure (PALF).

METHODS

This multicenter, retrospective cohort study was conducted in 13 pediatric intensive care units in Shandong Province, China. DPMAS+PE and single PE therapies were performed in 28 and 50 cases, respectively. The patients' clinical information and biochemical data were obtained from the patients' medical records.

RESULTS

The severity of illness did not differ between the 2 groups. At 72 hours after treatment, comparing with PE group, the rates of decline of Pediatric model for End-stage Liver Disease and Pediatric Sequential Organ Failure Assessment scores as well as total bilirubin blood ammonia and interleukin-6 were significantly higher, while the short-term effective rate (75.0% vs 44.0%, P = 0.008) was significantly higher in the DPMAS+PE group. The volume of plasma consumption (26.5 vs 51.0 mL/kg, P = 0.000) and the rate of adverse events (3.6% vs 24.0%, P = 0.026) were lower in the DPMAS+PE group than in the PE group, respectively. However, there was no statistical difference in the 28-day mortality between the 2 groups (21.4% vs 40.0%, P > 0.05).

CONCLUSIONS

For PALF patients, both DPMAS + half-dose PE and full-dose PE could improve the liver function, while DPMAS + half-dose PE could significantly reduce plasma consumption without obvious adverse effects in contrast with full-dose PE. Thus, DPMAS + half-dose PE may be a suitable alternative method for PALF in the context of the increasingly tight blood supply situation.

S100B Protein but Not 3-Nitrotyrosine Positively Correlates with Plasma Ammonia in Patients with Inherited Hyperammonemias: A New Promising Diagnostic Tool?

Individuals with inherited hyperammonemias often present developmental and intellectual deficiencies which are likely to be exaggerated by hyperammonemia episodes in long-term outcomes. In order to find a new, systemic marker common to the course of congenital hyperammonemias, we decided to measure the plasma level of S100 calcium-binding protein B (S100B), which is associated with cerebral impairment. Further, we analyzed three mechanistically diverged but linked with oxidative-nitrosative stress biochemical parameters: 3-nitrotyrosine (3-NT), a measure of plasma proteins' nitration; advanced oxidation protein products (AOPP), a measure of protein oxidation; and glutathione peroxidase (GPx) activity, a measure of anti-oxidative enzymatic capacity. The plasma biomarkers listed above were determined for the first time in congenital hyperammonemia. Also, the level of pro- and anti-inflammatory mediators (i.e., IL-12, IL-6, IL-8, TNF-α, IL-1β, and IL-10) and chemokines (IP-10, MCP-1, MIG, and RANTES) were quantified. S100B was positively correlated with plasma ammonia level, while noticeable levels of circulating 3-NT in some of the patients' plasma did not correlate with ammonia concentration. Overall, the linear correlation between ammonia and S100B but not standard oxidative stress-related markers offers a unique perspective for the future identification and monitoring of neurological deficits risk-linked with hyperammonemia episodes in patients with inherited hyperammonemias. The S100B measure may support the development of therapeutic targets and clinical monitoring in these disorders.

Serum S100B Levels in Patients with Liver Cirrhosis and Hepatic Encephalopathy

Hepatic encephalopathy (HE) is one of the main complications of liver cirrhosis (LC) and is classified into minimal hepatic encephalopathy (MHE) and overt hepatic encephalopathy (overt HE). S100B is expressed mainly in astrocytes and other glial cells, and S100B has been reported to be associated with various neurological disorders. The present study aimed to investigate the diagnostic ability of serum S100B to discriminate the grade of HE and the parameters correlated with serum S100B levels. Additionally, we investigated whether serum S100B levels can be used to predict 1-year mortality in cirrhotic patients. In total, 95 cirrhotic patients were consecutively enrolled and divided into the following three groups: (i) without any types of HEs; (ii) with MHE; and (iii) with overt HE. The diagnosis of MHE was made by the Mini-Mental State Examination (MMSE) and Psychometric Hepatic Encephalopathy Score (PHES). Among the three groups, there were no significant differences in serum S100B levels regardless of HE severity. The clinical parameters correlated with serum S100B levels were age, serum bilirubin, and creatinine levels. The Model for End-Stage Liver Disease (MELD) score showed a significant positive correlation with serum S100B levels. The relationship between serum S100B levels and MELD score was maintained in 48 patients without any type of HE. Additionally, hyperammonemia, low cholesterol levels, and the combination of serum S100B levels ≥ 35 pg/mL with MELD score ≥ 13 were factors for predicting 1- year mortality. In conclusion, serum S100B level was not useful for differentiating the severity of HE. However, we found that serum S100B levels can be affected by age, serum bilirubin, and creatinine in cirrhotic patients and are associated with MELD scores. Additionally, serum S100B levels showed the possibility of predicting 1-year mortality in cirrhotic patients. These findings suggest that serum S100B levels may reflect liver dysfunction and prognosis in liver disease.

The Immune Pathogenesis of Acute-On-Chronic Liver Failure and the Danger Hypothesis

Acute-on-chronic liver failure (ACLF) is a group of clinical syndromes related to severe acute liver function impairment and multiple-organ failure caused by various acute triggering factors on the basis of chronic liver disease. Due to its severe condition, rapid progression, and high mortality, it has received increasing attention. Recent studies have shown that the pathogenesis of ACLF mainly includes direct injury and immune injury. In immune injury, cytotoxic T lymphocytes (CTLs), dendritic cells (DCs), and CD4⁺ T cells accumulate in the liver tissue, secrete a variety of proinflammatory cytokines and chemokines, and recruit more immune cells to the liver, resulting in immune damage to the liver tissue, massive hepatocyte necrosis, and liver failure, but the key molecules and signaling pathways remain unclear. The “danger hypothesis” holds that in addition to the need for antigens, damage-associated molecular patterns (DAMPs) also play a very important role in the occurrence of the immune response, and this hypothesis is related to the pathogenesis of ACLF. Here, the research status and development trend of ACLF, as well as the mechanism of action and research progress on various DAMPs in ACLF, are summarized to identify biomarkers that can predict the occurrence and development of diseases or the prognosis of patients at an early stage.

S100 Beta Protein as a Marker of Hepatic Encephalopathy: A Breakthrough in Diagnostics or a False Trail? Review of the Literature

Hepatic encephalopathy is a dysfunction of the central nervous system caused by chronic and acute liver disease. The dysfunction presents a wide spectrum of symptoms—from the undetectable in a standard clinical examination to hepatic coma—and could be caused by both chronic and acute liver diseases. For many years research has been conducted to find a marker that would allow for the accurate, quick, and possibly inexpensive detection of hepatic encephalopathy. Due to the pathogenesis of hepatic encephalopathy, researchers’ attention is focused on markers of damage to the central nervous system. One of the markers of astrocyte damage, known from research in neurology and neurosurgery, is the protein S100B. Published research results so far are inconclusive, but they allow us to look with optimism at the role of S100B as a marker of minimal hepatic encephalopathy (MHE).

North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper on the Diagnosis and Management of Pediatric Acute Liver Failure

ABSTRACT

Pediatric acute liver failure (PALF) is a rare, rapidly progressive clinical syndrome with significant morbidity and mortality. The phenotype of PALF manifests as abrupt onset liver dysfunction, which can be brought via disparate etiology. Management is reliant upon intensive clinical care and support, often provided by the collaborative efforts of hepatologists, critical care specialists, and liver transplant surgeons. The construction of an age-based diagnostic approach, the identification of a potential underlying cause, and the prompt implementation of appropriate therapy can be lifesaving; however, the dynamic and rapidly progressive nature of PALF also demands that diagnostic inquiries be paired with monitoring strategies for the recognition and treatment of common complications of PALF. Although liver transplantation can provide a potential life-saving therapeutic option, the ability to confidently determine the certainness that liver transplant is needed for an individual child has been hampered by a lack of adequately tested clinical decision support tools and accurate predictive models. Given the accelerated progress in understanding PALF, we will provide clinical guidance to pediatric gastroenterologists and other pediatric providers caring for children with PALF by presenting the most recent advances in diagnosis, management, pathophysiology, and associated outcomes.

Role of Brain Biomarkers S-100-Beta and Neuron-Specific Enolase for Detection and Follow-Up of Hepatic Encephalopathy in Cirrhosis before, during and after Treatment with L-Ornithine-L-Aspartate

INTRODUCTION

Hepatic encephalopathy (HE), in the context of liver cirrhosis, seems to result from low-grade cerebral edema of the astrocytes. Serum brain biomarkers S-100-beta und neuron-specific enolase (NSE) are often elevated in brain injury. We hypothesized that neuromarkers S-100-beta and NSE can be used in the diagnosis of HE, compared with standardized diagnostic tools.

MATERIAL AND METHODS

A prospective non-randomized intervention study was performed using L-ornithine-L-aspartate (LOLA) for HE treatment. Primary endpoint was the evaluation of neuromarkers S-100-beta and NSE for detection and diagnosis of follow-up of HE. As secondary endpoints, the efficacy of LOLA on the course of HE and the diagnostic role of Portosystemic-Encephalopathy-Syndrome score (PHES) and critical flicker frequency (CFF) were analyzed. For diagnosis of covert (CHE) and overt (OHE) HE, West-Haven criteria (WHC), PHES and CFF were assessed at study entry. LOLA was applied (20 g i.v.) for 6 days. At the end of the study, HE evaluation was repeated. S-100-beta, NSE and ammonia were assessed in each patient before, during and after therapy with LOLA.

RESULTS

30 patients were included. At study entry, CHE was diagnosed in 50% and OHE in 50% of all subjects. A total of 25 participants completed the study. After LOLA therapy, deterioration of HE occurred in <11%, while most patients showed improvement (e.g. improved CFF in 79%). No significant correlation with HE severity (as diagnosed by WHC, PHES and CFF) could be demonstrated for any biochemical parameter. In addition, there were no significant changes in brain biomarkers during the treatment period.

DISCUSSION

While CFF as well as PHES showed good correlation with treatment response, S-100-beta and NSE did not significantly correlate with HE severity compared to proven diagnostic methods, and do not seem reliable biochemical markers for the follow-up under therapy.