Hepatic Encephalopathy and Liver Transplantation: The Past, Present, and Future Toward Equitable Access

The Health Care Burden of Hepatic Encephalopathy

Hepatic encephalopathy-a common and debilitating complication of cirrhosis-results in major health care burden on both patients and caregivers through direct and indirect costs. In addition to risk of falls, inability to work and drive, patients with hepatic encephalopathy often require hospital admission (and often readmission), and many require subacute care following hospitalization. The costs and psychological impact of liver transplantation often ensue. As the prevalence of chronic liver disease increases throughout the United States, the health care burden of hepatic encephalopathy will continue to grow.

Clinical Impact and Risk Factors of Seizure After Liver Transplantation: A Nested Case-Control Study

Seizures are a frequent neurological consequence following liver transplantation (LT), however, research on their clinical impact and risk factors is lacking. Using a nested case-control design, patients diagnosed with seizures (seizure group) within 1-year post-transplantation were matched to controls who had not experienced seizures until the corresponding time points at a 1:5 ratio to perform survival and risk factor analyses. Seizures developed in 61 of 1,243 patients (4.9%) at median of 11 days after LT. Five-year graft survival was significantly lower in the seizure group than in the controls (50.6% vs. 78.2%, respectively, p < 0.001) and seizure was a significant risk factor for graft loss after adjusting for variables (HR 2.04, 95% CI 1.24-3.33). In multivariable logistic regression, body mass index <23 kg/m2, donor age ≥45 years, intraoperative continuous renal replacement therapy and delta sodium level ≥4 mmol/L emerged as independent risk factors for post-LT seizure. Delta sodium level ≥4 mmol/L was associated with seizures, regardless of the severity of preoperative hyponatremia. Identifying and controlling those risk factors are required to prevent post-LT seizures which could result in worse graft outcome.

Dynamic evolution of brain structural patterns in liver transplantation recipients: a longitudinal study based on 3D convolutional neuronal network model

OBJECTIVES

To evaluate the dynamic evolution process of overall brain health in liver transplantation (LT) recipients, we employed a deep learning-based neuroanatomic biomarker to measure longitudinal changes of brain structural patterns before and 1, 3, and 6 months after surgery.

METHODS

Because of the ability to capture patterns across all voxels from a brain scan, the brain age prediction method was adopted. We constructed a 3D-CNN model through T1-weighted MRI of 3609 healthy individuals from 8 public datasets and further applied it to a local dataset of 60 LT recipients and 134 controls. The predicted age difference (PAD) was calculated to estimate brain changes before and after LT, and the network occlusion sensitivity analysis was used to determine the importance of each network in age prediction.

RESULTS

The PAD of patients with cirrhosis increased markedly at baseline (+ 5.74 years) and continued to increase within one month after LT (+ 9.18 years). After that, the brain age began to decrease gradually, but it was still higher than the chronological age. The PAD values of the OHE subgroup were higher than those of the no-OHE, and the discrepancy was more obvious at 1-month post-LT. High-level cognition-related networks were more important in predicting the brain age of patients with cirrhosis at baseline, while the importance of primary sensory networks increased temporarily within 6-month post-LT.

CONCLUSIONS

The brain structural patterns of LT recipients showed inverted U-shaped dynamic change in the early stage after transplantation, and the change in primary sensory networks may be the main contributor.

KEY POINTS

• The recipients' brain structural pattern showed an inverted U-shaped dynamic change after LT. • The patients' brain aging aggravated within 1 month after surgery, and the subset of patients with a history of OHE was particularly affected. • The change of primary sensory networks is the main contributor to the change in brain structural patterns.

A double-blind randomized placebo-controlled trial of albumin in outpatients with hepatic encephalopathy: HEAL study

BACKGROUND & AIMS

Even after recovery from overt hepatic encephalopathy (HE), minimal HE (MHE), which impairs quality of life (QoL), can persist. A double-blind, placebo-controlled randomized clinical trial was performed to determine the impact of albumin vs. saline on MHE and QoL in individuals with prior HE already on standard of care.

METHODS

Outpatients with cirrhosis and prior HE, MHE and hypoalbuminemia already on treatment for HE were included. Patients on regular IV albumin infusions were excluded. Participants were randomized 1:1 to receive either weekly infusions of 25% IV albumin 1.5 g/kg or saline over 5 weeks. MHE was defined using either psychometric hepatic encephalopathy score (PHES), Stroop or critical clicker frequency. MHE, QoL (based on sickness impact profile [SIP] total, physical, psychosocial domain) and serum markers (inflammation, endothelial dysfunction, and ischemia-modified albumin) were compared between baseline, the final infusion visit (end-of-drug [EOD]) and 1-week post final infusion (end-of-study [EOS]).

RESULTS

Forty-eight (24/group) participants were randomized and balanced (including by HE medication use) at baseline. Adverse events were similar, with MELD and ammonia remaining stable between/within groups. Albumin levels increased and ischemia-modified albumin decreased only in the albumin group at EOD and EOS vs. baseline. PHES and Stroop MHE reversal and improvement were greater in the albumin group at EOD and persisted at EOS. SIP total and psychosocial, but not physical, domain improved only in the albumin group at EOD and EOS vs. baseline. A significant reduction in IL-1β and endothelial dysfunction markers was also observed in the albumin group.

CONCLUSION

In a double-blind, placebo-controlled trial of outpatients with cirrhosis, prior HE and current MHE, albumin infusions were associated with improved cognitive function and psychosocial QoL, likely due to amelioration of endothelial dysfunction.

CLINICAL TRIALS REGISTRATION

www.

CLINICALTRIALS

gov NCT03585257.

IMPACT AND IMPLICATIONS

Even after recovery from overt hepatic encephalopathy (HE), minimal HE (MHE), which impairs quality of life, can persist. We found that intravenous albumin infusions were associated with improved cognitive function and psychosocial quality of life, likely owing to amelioration of endothelial dysfunction, compared to placebo in outpatients with prior HE and current MHE. In patients who continue to demonstrate cognitive dysfunction and impaired quality of life despite standard of care therapy for HE, albumin infusions could be considered if these results are validated.

Green Tea Catechin EGCG Ameliorates Thioacetamide-Induced Hepatic Encephalopathy in Rats via Modulation of the Microbiota-Gut-Liver Axis

SCOPE

Existing research suggests that (-)-epigallocatechin-3-gallate (EGCG), which is a natural tea catechin active substance, can protect against liver injury. However, its mechanism for hepatic encephalopathy (HE) treatment is still unclear. In this study, the role of EGCG in the amelioration of HE rats and the effect on the microbiota-gut-liver axis are mainly analyzed.

METHODS AND RESULTS

Thioacetamide (TAA) is employed to induce the HE model in rats. The results of open field test show that EGCG restores locomotor activity and exploratory behavior. Histological and biochemical results demonstrate that EGCG ameliorates brain and liver damage, decreases the expression of pro-inflammatory cytokines, and increases the activity of antioxidant enzymes. Meanwhile, EGCG modulates the Nrf2 pathway and TLR4/NF-κB pathway to mitigate TAA-induced oxidative stress and inflammatory responses. Immunohistochemistry reveals protection of the intestinal barrier by EGCG upregulating the expression of occludin and zonula occludens-1. Furthermore, serum levels of ammonia and LPS are reduced. 16S rRNA analysis shows that EGCG treatment increases the abundance of beneficial bacteria (e.g., Bifidobacterium, Lactobacillus, and Limosilactobacillus).

CONCLUSION

The above results reveal that EGCG has anti-oxidative stress and anti-inflammatory effects, and ameliorates the condition through the microbiota-gut-liver axis, with potential for the treatment of HE.

Spotlight on liver macrophages for halting liver disease progression and injury

INTRODUCTION

Over the past two decades, understanding of hepatic macrophage biology has provided astounding details of their role in the progression and regression of liver diseases. The hepatic macrophages constitute resident macrophages, Kupffer cells, and circulating bone marrow monocyte-derived macrophages, which play a diverse role in liver injury and repair. Imbalance in the macrophage population leads to pathological consequences and is responsible for the initiation and progression of acute and chronic liver injuries. Further, distinct populations of hepatic macrophages and their high heterogeneity make their complex role enigmatic. The unique features of distinct phenotypes of macrophages have provided novel biomarkers for defining the stages of liver diseases. The distinct mechanisms of hepatic macrophages polarization and recruitment have been at the fore front of research. In addition, the secretome of hepatic macrophages and their immune regulation has provided clinically relevant therapeutic targets.

AREAS COVERED

Herein we have highlighted the current understanding in the area of hepatic macrophages, and their role in the progression of liver injury.

EXPERT OPINION

It is essential to ascertain the physiological and pathological role of evolutionarily conserved distinct macrophage phenotypes in different liver diseases before viable approaches may see a clinical translation.

EASL Clinical Practice Guidelines on the management of hepatic encephalopathy

The EASL Clinical Practice Guidelines (CPGs) on the management of hepatic encephalopathy (HE) present evidence-based answers to a set of relevant questions (where possible, formulated in PICO [patient/population, intervention, comparison and outcomes] format) on the definition, diagnosis, differential diagnosis and treatment of HE. The document does not cover the pathophysiology of HE and does not cover all available treatment options. The methods through which it was developed and any information relevant to its interpretation are also provided.

Impact of Optimizing the Emergency Care Process on the Emergency Effect and Prognosis of Patients with Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a serious complication caused by liver disease and is one of the leading causes of death in patients. Studies have shown that proper emergency care for patients after the occurrence of HE can improve their prognosis and quality of life. Therefore, this study focuses on the effect of optimizing the emergency care process on the effectiveness and prognosis of emergency care for patients with hepatic encephalopathy. In this study, we set 32 patients with HE admitted to receive routine emergency care between May 2020 and March 2021 as the control group and 34 patients with HE admitted to receive optimized emergency care processes between April 2021 and February 2022 as the observation group. The satisfaction of patients' families with this care was assessed using a self-administered nursing satisfaction questionnaire to record the outcome of emergency care, quality of care, and prognosis of patients in the two groups of palliative care. The data collected were analyzed using SPSS17.0 software, and the results showed that the time spent on diagnosis, resuscitation, DTP, and DTT was much lower in the observation group than in the control group, and the scores related to the quality of care, such as ambulance technique, humanistic care, resuscitation efficiency, and resuscitation effect, were all higher than those of the control group, and the satisfaction of the family members in the observation group was also significantly higher than that of the control group (P < 0.05). The success rate of first aid in the observation group was 100.00%, which was higher than 93.72% in the control group, but the difference between the two groups was not significant (P > 0.05). It can be seen that the application of an optimized emergency nursing process in HE patients is effective, which can effectively improve the success rate of HE resuscitation, shorten the resuscitation time and condition diagnosis, improve the resuscitation effect, improve the quality of nursing care, and improve the prognosis of patients to a certain extent.