Serum endotoxin, inflammatory mediators, and magnetic resonance spectroscopy before and after treatment in patients with minimal hepatic encephalopathy

Prophylaxis of hepatic encephalopathy: current and future drug targets

Hepatic encephalopathy is described by a broad spectrum of neurological and psychiatric aberrations resulting due to advanced liver dysfunction. It is a neurological disorder due to hepatic insufficiency and/or portosystemic shunts. Its clinical presentation includes neuropsychiatric dysfunction ranging from subclinical changes to comatose state. It is a sign of poor prognosis in cirrhotics with a high 1-year mortality. Each episode of hepatic encephalopathy leads to high hospitalization rate, poor prognosis and raised burden of healthcare. Primary prophylaxis is prevention of initial occurrence and secondary prophylaxis is prevention of reappearance of hepatic encephalopathy in subjects who had prior history. Early detection and management of triggers is very important in the treatment of hepatic encephalopathy. The initial choice of treatment is still lactulose, as it is effective in minimal, overt, and recurrent hepatic encephalopathy. Rifaximin is equally effective as lactulose in managing hepatic encephalopathy and is better tolerated. Branch chain amino acids are beneficial in subjects who are protein intolerant. L-ornithine L-aspartate and probiotics are also useful in the management of hepatic encephalopathy. Rifaximin along with lactulose is effective in managing overt and recurrent hepatic encephalopathy. Large portosystemic shunts embolization and liver transplant is efficacious in certain group of patients. Nutritional therapy and fecal microbiota transplantation are newer therapies for hepatic encephalopathy but the evidences are limited, more research is required to prove their efficacy. Involvement of hospital pharmacists, telemedicine, and providing education are also beneficial in managing hepatic encephalopathy.

[WITHDRAWN] Serum biomarkers of liver fibrosis identify changes in striatal metabolite levels

The full text of this preprint has been withdrawn by the authors due to author disagreement with the posting of the preprint. Therefore, the authors do not wish this work to be cited as a reference. Questions should be directed to the corresponding author.

Efficacy and Safety of Variable Treatment Options in the Prevention of Hepatic Encephalopathy: A Systematic Review and Network Meta-Analysis

There are no guidelines for the most effective medication to reduce hepatic encephalopathy (HE) or the associated mortality. The purpose of this study is to determine the most effective possible treatment among the single treatment options or the combined treatment options for decreasing the morbidity and mortality of HE. We evaluated the outcomes by various parameters such as the quality of life, reduction in ammonia, all causes of mortality, adverse events, reversal of minimal HE, and development of overt HE. We systematically searched PubMed, Cochrane, Web of Science, and Scopus till the 19th of January 2023 for studies that assess various treatment options for HE. Data were extracted from eligible studies and pooled in a frequentist network meta-analysis as standardized mean difference (SMD) and their 95% confidence interval (CI) using the MetaInsight web-based tool. The Cochrane Tool was used to assess the randomized controlled trials' quality (RCT), while the NIH tool was used to assess the quality of the included cohort studies. Utilizing the R software, the network meta-analysis was conducted. In addition to a significant variation in cases of (Lactulose and Rifaximin) compared with Rifaximin (RR= 0.39, 95% CI [0.17; 0.89]), the results demonstrated a significantly lower incidence of overt HE in (Lactulose and Rifaximin) compared with placebo (RR=0.19, 95% CI [0.09; 0.40]). Most arms demonstrated a statistically significant reduction in the incidence of overt HE compared to albumin and placebo. The results also demonstrated a significant reduction in ammonia between L-ornithine-L-aspartate (LOLA) and probiotics (MD= -19.17, 95% CI [-38.01; -0.32]), as well as a significant difference in the incidence of LOLA compared to placebo (MD= -22.62, 95% CI [-39.16; -6.07]). This network meta-analysis has significant data for managing subclinical HE in people without a history of overt HE. Our analysis showed that (Lactulose and Rifaximin), followed by (Rifaximin and L-carnitine), followed by (Lactulose and Rifaximin with zinc) were the best combinations regarding overt HE. LOLA reduced ammonia best, followed by Nitazoxanide and finally Lactulose. (Lactulose and Nitazoxanide) have the least adverse effects, followed by (Rifaximin and L-carnitine), then Probiotics. Yet, all mortality outcomes and quality of life changes yielded no useful findings. Future studies like RCTs must be done to compare our therapies directly.

Identifying Minimal Hepatic Encephalopathy: A New Perspective from Magnetic Resonance Imaging

Type C hepatic encephalopathy (HE) is a condition characterized by brain dysfunction caused by liver insufficiency and/or portal-systemic blood shunting, which manifests as a broad spectrum of neurological or psychiatric abnormalities, ranging from minimal HE (MHE), detectable only by neuropsychological or neurophysiological assessment, to coma. Though MHE is the subclinical phase of HE, it is highly prevalent in cirrhotic patients and strongly associated with poor quality of life, high risk of overt HE, and mortality. It is, therefore, critical to identify MHE at the earliest and timely intervene, thereby minimizing the subsequent complications and costs. However, proper and sensitive diagnosis of MHE is hampered by its unnoticeable symptoms and the absence of standard diagnostic criteria. A variety of neuropsychological or neurophysiological tests have been performed to diagnose MHE. However, these tests are nonspecific and susceptible to multiple factors (eg, aging, education), thereby limiting their application in clinical practice. Thus, developing an objective, effective, and noninvasive method is imperative to help detect MHE. Magnetic resonance imaging (MRI), a noninvasive technique which can produce many objective biomarkers by different imaging sequences (eg, Magnetic resonance spectroscopy, DWI, rs-MRI, and arterial spin labeling), has recently shown the ability to screen MHE from NHE (non-HE) patients accurately. As advanced MRI techniques continue to emerge, more minor changes in the brain could be captured, providing new means for early diagnosis and quantitative assessment of MHE. In addition, the advancement of artificial intelligence in medical imaging also presents the potential to mine more effective diagnostic biomarkers and further improves the predictive efficiency of MHE. Taken together, advanced MRI techniques may provide a new perspective for us to identify MHE in the future. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Do gut microbiome-targeted therapies improve liver function in cirrhotic patients? A systematic review and meta-analysis

BACKGROUND AND AIM

Microbiome-targeted therapies (MTTs) are considered as promising interventions for cirrhosis, but the impact of gut microbiome modulation on liver function and disease severity has not been fully assessed. We comprehensively evaluated the efficacy of MTTs in patients with liver cirrhosis.

METHODS

Data from randomized controlled trials were collected through MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrial.gov from inception to February 20, 2023. Clinical outcomes were pooled and expressed in terms of risk ratios or mean differences (MD). Additional subgroup and sensitivity analyses were performed to validate the robustness of findings. A trial sequential analysis was applied to calculate the required information size and evaluate the credibility of the meta-analysis results.

RESULTS

Twenty-one studies with a total of 1699 cirrhotic patients were included for meta-analysis. MTTs were associated with a significant reduction in aspartate aminotransferase (MD, -3.62; 95% CI, -6.59 to -0.65), the risk of hepatic encephalopathy (risk ratio = 0.56, 95% CI: 0.46 to 0.68), model for end-stage liver disease score (MD, -0.90; 95% CI, -1.17 to -0.11), ammonia (MD, -11.86; 95% CI, -16.39 to -7.33), and endotoxin (MD, -0.14; 95% CI, -0.23 to -0.04). The trial sequential analysis yielded reliable results of these outcomes. No effects were observed on the changes of other hepatic function indicators.

CONCLUSION

MTTs appeared to be associated with a slowed deterioration in liver cirrhosis, which could provide reference for clinicians in treatment of cirrhotic patients based on their conditions.

Sarcopenia in cirrhosis: Prospects for therapy targeted to gut microbiota

Decreased muscle mass and function, also known as sarcopenia, is common in patients with cirrhosis and is associated with a poor prognosis. Although the pathogenesis of this disorder has not been fully elucidated, a disordered gut-muscle axis probably plays an important role. Decreased barrier function of the gut and liver, gut dysbiosis, and small intestinal bacterial overgrowth (SIBO) can lead to increased blood levels of ammonia, lipopolysaccharides, pro-inflammatory mediators, and myostatin. These factors have complex negative effects on muscle mass and function. Drug interventions that target the gut microbiota (long-term use of rifaximin, lactulose, lactitol, or probiotics) positively affect most links of the compromised gut-muscle axis in patients with cirrhosis by decreasing the levels of hyperammonemia, bacterial translocation, and systemic inflammation and correcting gut dysbiosis and SIBO. However, although these drugs are promising, they have not yet been investigated in randomized controlled trials specifically for the treatment and prevention of sarcopenia in patients with cirrhosis. No data exist on the effects of fecal transplantation on most links of gut-muscle axis in cirrhosis; however, the results of animal experimental studies are promising.

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.

Gut Microbiota and Neuroinflammation in Acute Liver Failure and Chronic Liver Disease

Acute liver failure and chronic liver disease are associated with a wide spectrum of neurological changes, of which the best known is hepatic encephalopathy (HE). Historically, hyperammonemia, causing astrocyte swelling and cerebral oedema, was considered the main etiological factor in the pathogenesis of cerebral dysfunction in patients with acute and/or chronic liver disease. However, recent studies demonstrated a key role of neuroinflammation in the development of neurological complications in this setting. Neuroinflammation is characterized by activation of microglial cells and brain secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, which alter neurotransmission, leading to cognitive and motor dysfunction. Changes in the gut microbiota resulting from liver disease play a crucial role in the pathogenesis of neuroinflammation. Dysbiosis and altered intestinal permeability, resulting in bacterial translocation and endotoxemia, are responsible for systemic inflammation, which can spread to brain tissue and trigger neuroinflammation. In addition, metabolites derived from the gut microbiota can act on the central nervous system and facilitate the development of neurological complications, exacerbating clinical manifestations. Thus, strategies aimed at modulating the gut microbiota may be effective therapeutic weapons. In this review, we summarize the current knowledge on the role of the gut-liver-brain axis in the pathogenesis of neurological dysfunction associated with liver disease, with a particular focus on neuroinflammation. In addition, we highlight emerging therapeutic approaches targeting the gut microbiota and inflammation in this clinical setting.

Hepatic Encephalopathy

Hepatic encephalopathy (HE) is brain dysfunction secondary to liver insufficiency or portosystemic shunting. HE is a major burden on patients and caregivers, impairs quality of life and is associated with higher mortality. Overt HE is a clinical diagnosis while Covert HE, needs specialized diagnostic strategies. Mainstay of treatment of HE is nonabsorbable disaccharides such as lactulose as well as rifaximin; however, investigational therapies are discussed in this review. Better tools are needed to prognosticate which patients will go on to develop HE but microbiome and metabolomic-driven strategies are promising. Here we review methods to prevent the HE development and admissions.

Role of gut microbiota in the pathogenesis and therapeutics of minimal hepatic encephalopathy via the gut-liver-brain axis

Minimal hepatic encephalopathy (MHE) is a frequent neurological and psychiatric complication of liver cirrhosis. The precise pathogenesis of MHE is complicated and has yet to be fully elucidated. Studies in cirrhotic patients and experimental animals with MHE have indicated that gut microbiota dysbiosis induces systemic inflammation, hyperammonemia, and endotoxemia, subsequently leading to neuroinflammation in the brain via the gut-liver-brain axis. Related mechanisms initiated by gut microbiota dysbiosis have significant roles in MHE pathogenesis. The currently available therapeutic strategies for MHE in clinical practice, including lactulose, rifaximin, probiotics, synbiotics, and fecal microbiota transplantation, exert their effects mainly by modulating gut microbiota dysbiosis. Microbiome therapies for MHE have shown promised efficacy and safety; however, several controversies and challenges regarding their clinical use deserve to be intensively discussed. We have summarized the latest research findings concerning the roles of gut microbiota dysbiosis in the pathogenesis of MHE via the gut-liver-brain axis as well as the potential mechanisms by which microbiome therapies regulate gut microbiota dysbiosis in MHE patients.

The shaping of gut immunity in cirrhosis

Cirrhosis is the common end-stage of chronic liver diseases of different etiology. The altered bile acids metabolism in the cirrhotic liver and the increase in the blood-brain barrier permeability, along with the progressive dysbiosis of intestinal microbiota, contribute to gut immunity changes, from compromised antimicrobial host defense to pro-inflammatory adaptive responses. In turn, these changes elicit a disruption in the epithelial and gut vascular barriers, promoting the increased access of potential pathogenic microbial antigens to portal circulation, further aggravating liver disease. After summarizing the key aspects of gut immunity during homeostasis, this review is intended to update the contribution of liver and brain metabolites in shaping the intestinal immune status and, in turn, to understand how the loss of homeostasis in the gut-associated lymphoid tissue, as present in cirrhosis, cooperates in the advanced chronic liver disease progression. Finally, several therapeutic approaches targeting the intestinal homeostasis in cirrhosis are discussed.

Evaluation of IL-6 for Stepwise Diagnosis of Minimal Hepatic Encephalopathy in Patients With Liver Cirrhosis

Diagnosis of minimal hepatic encephalopathy (MHE) requires psychometric testing, which is time-consuming and often neglected in clinical practice. Elevated Interleukin-6 (IL-6) serum levels have been linked to MHE. The aim of this study was to investigate the usefulness of IL-6 as a biomarker in a stepwise diagnostic algorithm to detect MHE in patients with liver cirrhosis. A total of 197 prospectively recruited patients without clinical signs of hepatic encephalopathy (HE) served as the development cohort. Another independent cohort consisting of 52 patients served for validation purposes. Psychometric Hepatic Encephalopathy Score (PHES) was applied for the diagnosis of MHE. Fifty (25.4%) patients of the development cohort presented with MHE. Median IL-6 levels were more than twice as high in patients with MHE than in patients without HE (16 vs. 7 pg/mL; P < 0.001). On multivariable logistic regression analysis, higher IL-6 levels (odds ratio 1.036; 95% confidence interval [CI] 1.009-1.064; P = 0.008) remained independently associated with the presence of MHE. IL-6 levels ≥ 8pg/mL discriminated best between patients with and without MHE in receiver operating characteristic (ROC) analysis (area under the ROC 0.751). With a cutoff value of ≥7 pg/mL, further elaborate testing with PHES could be avoided in 38% of all patients with a sensitivity of 90% (95% CI 77%-96%) and a negative predictive value (NPV) of 93% (95% CI 84%-98%). This diagnostic accuracy was confirmed in the validation cohort (sensitivity 94%; NPV 93%). Conclusion: Using IL-6 serum levels as a biomarker in a stepwise diagnostic algorithm to detect MHE could substantially reduce the number of patients requiring testing with PHES and in turn the workload. IL-6 may have especially helped in patients who are unable to perform other screening tests.

A narrative review of the role of gastrointestinal dysbiosis in the pathogenesis of polycystic ovary syndrome

Diet-induced gastrointestinal dysbiosis has been hypothesized to play a significant role in stimulating an increase in gastrointestinal permeability and activating systemic inflammation in women with polycystic ovary syndrome (PCOS). We reviewed the current proof-of-concept studies on the proposed mechanism of dysbiosis in the pathogenesis of PCOS. A literature search was performed to identify articles on changes in the intestinal microbiome (dysbiosis) and increased intestinal mucosal permeability involving lipopolysaccharide (LPS), LPS-binding protein (LPS-BP), and zonulin. We also searched for systematic reviews and meta-analyses that synthesized the results of studies on the therapeutic effects of prebiotics, probiotics, or synbiotics in women with PCOS. Our search was confined to human studies between 2012 and 2021 using the PubMed, Scopus, and Cochrane databases. Thirty-one studies met the inclusion criteria (14 microbiota, 1 LPS, 1 LPS-BP, 1 LPS and LPS-BP, 5 zonulin, 9 systematic reviews). Our analysis revealed that most studies reported reduced alpha diversity and dysbiosis in women with PCOS. Preliminary studies suggest that LPS, LPS-BP, and zonulin may be involved in the pathophysiology of increased intestinal permeability. Treatment of PCOS with prebiotics, probiotics, and synbiotics appears to have a range of beneficial effects on metabolic and biochemical profiles. This review highlights the need for continued research into the pathophysiological mechanisms of dysbiosis and the clinical efficacy of prebiotics, probiotics, and synbiotics in women with PCOS.

Current approach to treatment of minimal hepatic encephalopathy in patients with liver cirrhosis

Minimal hepatic encephalopathy (MHE) corresponds to the earliest stage of hepatic encephalopathy (HE). MHE does not present clinically detectable neurological-psychiatric abnormalities but is characterized by imperceptible neurocognitive alterations detected during routine clinical examination via neuropsychological or psychometrical tests. MHE may affect daily activities and reduce job performance and quality of life. MHE can increase the risk of accidents and may develop into overt encephalopathy, worsening the prognosis of patients with liver cirrhosis. Despite a lack of consensus on the therapeutic indication, interest in finding novel strategies for prevention or reversion has led to numerous clinical trials; their results are the main objective of this review. Many studies address the treatment of MHE, which is mainly based on the strategies and previous management of overt HE. Current alternatives for the management of MHE include measures to maintain nutritional status while avoiding sarcopenia, and manipulation of intestinal microbiota with non-absorbable disaccharides such as lactulose, antibiotics such as rifaximin, and administration of different probiotics. This review analyzes the results of clinical studies that evaluated the effects of different treatments for MHE.

The Psychometric Hepatic Encephalopathy Syndrome score does not correlate with blood ammonia, endotoxins or markers of inflammation in patients with cirrhosis

Background

The pathogenesis of hepatic encephalopathy (HE) remains unclear but impaired clearance of gut-derived neurotoxins and increased systemic inflammation are thought to play key roles. The diagnosis is based on detection of neurophysiological and neuropsychometric abnormalities. The Psychometric Hepatic Encephalopathy Score (PHES) have been found to correlate with markers of systematic inflammation including interleukin 6, C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α). This study explores the associations between the PHES score and systemic inflammation, endotoxins and disease severity using baseline data from a trial involving patients with cirrhosis and minimal or no HE (NCT01769040).

Methods

Arterial blood was obtained during hepatic vein catheterization, from 54 patients [median age 55 (range, 33-70) years; 83% men] with decompensated but stable cirrhosis. None had clinical evidence of HE but 34 (55.6%) had an abnormal PHES score indicating the presence of minimal HE. Relationships were sought between the PHES score and markers of systemic inflammation, high sensitivity-CRP, cytokines (SDF-1α, TGF-b1, IP-10, IL-6, 10 and 18, and TNF-α; lipopolysaccharide (LPS), the lipopolysaccharide binding protein (LBP) and soluble CD14 (sCD14); and the blood ammonia.

Results

No significant relationships were found between the PHES score and any of the variables tested with the single exception of the correlation with serum IL-6 (r=-0.29, 95% confidence interval, -0.53 to -0.02, P=0.031). No independent predictors of the PHES score were identified in regression analyses.

Conclusions

No predictive associations were identified between the PHES scores and circulating blood ammonia, endotoxins, or markers of systemic inflammation in this patient population.

Interplay of cardiovascular mediators, oxidative stress and inflammation in liver disease and its complications

The liver is a crucial metabolic organ that has a key role in maintaining immune and endocrine homeostasis. Accumulating evidence suggests that chronic liver disease might promote the development of various cardiac disorders (such as arrhythmias and cardiomyopathy) and circulatory complications (including systemic, splanchnic and pulmonary complications), which can eventually culminate in clinical conditions ranging from portal and pulmonary hypertension to pulmonary, cardiac and renal failure, ascites and encephalopathy. Liver diseases can affect cardiovascular function during the early stages of disease progression. The development of cardiovascular diseases in patients with chronic liver failure is associated with increased morbidity and mortality, and cardiovascular complications can in turn affect liver function and liver disease progression. Furthermore, numerous infectious, inflammatory, metabolic and genetic diseases, as well as alcohol abuse can also influence both hepatic and cardiovascular outcomes. In this Review, we highlight how chronic liver diseases and associated cardiovascular effects can influence different organ pathologies. Furthermore, we explore the potential roles of inflammation, oxidative stress, vasoactive mediator imbalance, dysregulated endocannabinoid and autonomic nervous systems and endothelial dysfunction in mediating the complex interplay between the liver and the systemic vasculature that results in the development of the extrahepatic complications of chronic liver disease. The roles of ageing, sex, the gut microbiome and organ transplantation in this complex interplay are also discussed.

Comparative Efficacy of Treatment Options for Minimal Hepatic Encephalopathy: A Systematic Review and Network Meta-Analysis

BACKGROUND & AIMS

We aimed to synthesize evidence for most effective treatments for minimal hepatic encephalopathy (HE) and prevention of overt HE in patients with cirrhosis.

METHODS

We performed a systematic search of the PubMed, EMBASE, OvidSP, and Cochrane Central Register of Controlled Trials databases through July 26, 2018, for randomized controlled trials evaluating treatments for minimal HE in patients with cirrhosis, with primary outcomes of reversal of minimal HE or prevention of overt HE. We conducted a meta-analysis and then used network meta-analysis and surface under cumulated ranking (SUCRA) to pool the direct and indirect estimates and rank the different treatments. We appraised study quality using the Grading of Recommendations Assessment, Development and Evaluation system.

RESULTS

Our meta-analysis and network meta-analysis included 25 trials, comprising 1563 participants. Agents found to be effective in reversing minimal HE compared with placebo or no treatment included rifaximin (odds ratio [OR], 7.53; 95% predictive interval [PrI], 4.45-12.73; SUCRA, 89.2%; moderate quality), lactulose (OR, 5.39; 95% PrI, 3.60-8.0; SUCRA, 67.2%; moderate quality), the combination of probiotics and lactulose (OR, 4.66; 95% PrI, 1.90-11.39; SUCRA, 52.4%; low quality), L-ornithine L-aspartate (OR, 4.45; 95% PrI, 2.67-7.42; SUCRA, 47.2%; low moderate quality), and probiotics (OR, 3.89; 95% PrI, 2.52-6.02; SUCRA, 34.1%; low quality). Agents found to be effective in preventing episodes of overt HE compared with placebo or no treatment included L-ornithine L-aspartate (OR, 0.19; 95% PrI, 0.04-0.91; SUCRA, 75.1%; high moderate quality), lactulose (OR, 0.22; 95% PrI, 0.09-0.52; SUCRA, 73.9%; moderate quality), and probiotics (OR, 0.27; 95% PrI, 0.11-0.62; SUCRA, 59.6%; low quality).

CONCLUSIONS

In a meta-analysis of data from 25 trials, we found rifaximin and lactulose to be most effective for reversal of minimal HE in patients with cirrhosis. L-ornithine L-aspartate and lactulose are most effective in the prevention of overt HE. Lactulose was the only agent that was effective in reversing minimal HE, preventing overt HE, reducing ammonia, and improving quality of life, with tolerable adverse effects. International prospective register of systematic reviews ID: 107003.

Minimal Hepatic Encephalopathy in Indians: Psychometric Hepatic Encephalopathy Score and Inhibitory Control Test for Diagnosis and Rifaximin or Lactulose for Its Reversal

Background and Aims: Psychometric hepatic encephalopathy score (PHES) is used widely for diagnosis of minimal hepatic encephalopathy (MHE). This prospective study aimed to determine the utility of the inhibitory control test (ICT) for the diagnosis of MHE. Additionally, the efficacy of rifaximin and lactulose for reversal of MHE was evaluated. Methods: A total of 180 eligible cirrhotic patients underwent testing for MHE. When PHES was ≤ -5 and ICT lures were ≥ 14, MHE was diagnosed. The 108 patients with MHE were randomized to three groups for treatment with either lactulose, rifaximin, or placebo. Treatment outcomes were measured at the end of 3 months. Results: The 108 patients with MHE diagnosed by PHES and/or ICT accounted for 60%. The diagnosis of MHE was made by both ICT and PHES positivity in 56 patients, by abnormal ICT and normal PHES in 37 patients, and by abnormal PHES and normal ICT in 15 patients. For diagnosis of MHE, ICT had sensitivity of 78.87%, specificity of 66.06% with 60.22% positive predictive value and 82.76% negative predictive value. An area under the curve value of 0.724 (95% CI: 0.653-0.788) was obtained for diagnosis of MHE. Reversal of MHE was seen in 71.42%, 70.27% and 11.11% of patients in the rifaximin, lactulose and placebo arms (p < 0.001). Rifaximin showed better tolerability compared to lactulose. Conclusions: For the diagnosis of MHE, ICT is a simple tool but has lower sensitivity and better specificity than PHES. Rifaximin is as efficacious as lactulose in the treatment of MHE and better tolerated.

cGMP signaling pathway in hepatic encephalopathy neuroinflammation and cognition

Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that results from liver failure and is characterized by a wide range of symptoms such as alteration in the sleep-waking cycle, neuromuscular coordination, mood, and cognition. The deregulation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) signaling pathway is thought to play an important role in the etiology and progression of neurodegenerative diseases, and several studies pointed that the cGMP signaling is impaired in patients with HE and experimental models of chronic hyperammonemia. This review aimed to briefly present the current knowledge of the cGMP signaling pathways in neuroinflammation, neurogenesis, and memory in hepatic encephalopathy and its potential therapeutic role.

Neuroimaging in alcohol use disorder: From mouse to man

This article provides an overview of recent advances in understanding the effects of alcohol use disorders (AUD) on the brain from the perspective of magnetic resonance imaging (MRI) research in preclinical models and clinical studies. As a noninvasive investigational tool permitting assessment of morphological, metabolic, and hemodynamic changes over time, MRI offers insight into the dynamic course of alcoholism beginning with initial exposure through periods of binge drinking and escalation, sobriety, and relapse and has been useful in differential diagnosis of neurological diseases associated with AUD. Structural MRI has revealed acute and chronic effects of alcohol on both white and gray matter volumes. MR Spectroscopy, able to quantify brain metabolites in vivo, has shed light on biochemical alterations associated with alcoholism. Diffusion tensor imaging permits microstructural characterization of white matter fiber tracts. Functional MRI has allowed for elucidation of hemodynamic responses at rest and during task engagement. Positron emission tomography, a non-MRI imaging tool, has led to a deeper understanding of alcohol-induced receptor and neurotransmitter changes during various stages of drinking and abstinence. Together, such in vivo imaging tools have expanded our understanding of the dynamic course of alcoholism including evidence for regional specificity of the effects of AUD, hints at mechanisms underlying the shift from casual to compulsive use of alcohol, and profound recovery with sustained abstinence.

Pathogenesis of Hepatic Encephalopathy in Chronic Liver Disease

Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that occurs during chronic liver disease (CLD). While ammonia and other precipitating factors in liver disease including inflammation, bile acids, oxidative stress, and lactate play a role in the pathogenesis of HE, the exact mechanism that leads to HE is not fully understood. Notably, accumulating evidence points toward a synergic effect rather than independent actions among precipitating factors that contributes to the development and severity of HE in CLD. Hence, this review is aimed to briefly discuss the single and synergic interplay of pathological factors in the progression and severity of HE.

Systemic inflammation without gliosis mediates cognitive deficits through impaired BDNF expression in bile duct ligation model of hepatic encephalopathy

Chronic liver disease per se induces neuroinflammation that contributes to cognitive deficits in hepatic encephalopathy (HE). However, the processes by which pro-inflammatory molecules result in cognitive impairment still remains unclear. In the present study, a significant increase in the activity of liver function enzymes viz. alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) was observed along with increase in plasma ammonia levels after four weeks of bile duct ligation (BDL) in rats suggesting hepatocellular damage. A significant increase was observed in mRNA expression of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) in brain regions and liver of BDL rats. Concomitantly, IL-6, TNF-α and MCP-1 protein levels were also increased in brain regions, liver and serum of BDL rats suggesting the involvement of blood-brain-axis in inflammatory response. However, a significant decrease was observed in glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule-1 (Iba-1) expression at transcriptional and translation level in brain of BDL rats. Immunohistochemical and flowcytometric analysis revealed reduced number of GFAP-immunopositive astrocytes and Iba1-immunopositive microglia in the brain regions of BDL rats. Further, a significant decline was observed in cognitive functions in BDL rats assessed using Morris water maze and novel object recognition tests. Expression of pro and mature form of brain derived neurotrophic factor (BDNF) and its upstream transcription element showed significant reduction in brain of BDL rats. Taken together, the results of the present study suggest that systemic inflammation and reduced expression of BDNF and its upstream transcription factor plays a key role in cognitive decline in HE.

Gut : liver : brain axis: the microbial challenge in the hepatic encephalopathy

Hepatic encephalopathy (HE) is a debilitating neuropsychiatric condition often associated with acute liver failure or cirrhosis. Advanced liver diseases are characterized by a leaky gut and systemic inflammation. There is strong evidence that the pathogenesis of HE is linked to a dysbiotic gut microbiota and to harmful microbial by-products, such as ammonia, indoles, oxindoles and endotoxins. Increased concentrations of these toxic metabolites together with the inability of the diseased liver to clear such products is thought to play an important patho-ethiological role. Current first line clinical treatments target microbiota dysbiosis by decreasing the counts of pathogenic bacteria, blood endotoxemia and ammonia levels. This review will focus on the role of the gut microbiota and its metabolism in HE and advanced cirrhosis. It will critically assess data from different clinical trials measuring the efficacy of the prebiotic lactulose, the probiotic VSL#3 and the antibiotic rifaximin in treating HE and advanced cirrhosis, through gut microbiota modulation. Additionally data from Randomised Controlled Trials using pre-, pro- and synbiotic will be also considered by reporting meta-analysis studies. The large amount of existing data showed that HE is a clear example of how an altered gut microbiota homeostasis can influence and impact on physiological functions outside the intestine, with implication for host health at the systems level. Nevertheless, a strong effort should be made to increase the information on gut microbiota ecology and its metabolic function in liver diseases and HE.

Gut Microbiome-based Therapeutics in Liver Cirrhosis: Basic Consideration for the Next Step

Infections account for significant morbidity and mortality in liver cirrhosis and most are related to the gut microbiome. Fecal dysbiosis, characterized by an overgrowth of potentially pathogenic bacteria and a decrease in autochthonous non-pathogenic bacteria, becomes prominent with the progression of liver cirrhosis. In cirrhotic patients, disruption of the intestinal barrier causes intestinal hyperpermeability (i.e. leaky gut), which is closely related to gut dysmotility, dysbiosis and small intestinal bacterial overgrowth and may induce pathological bacterial translocation. Although the involved microbial taxa are somewhat different between the cirrhotic patients from the East and the West, the common manifestation of a shortage of bacteria that contribute to the production of short-chain fatty acids and secondary bile acids may facilitate intestinal inflammation, leaky gut and gut dysbiosis. Translocated endotoxin and bacterial DNA are capable of provoking potent inflammation and affecting the metabolic and hemodynamic systems, which may ultimately enhance the progression of liver cirrhosis and its various complications, such as hepatic encephalopathy (HE), variceal bleeding, infection and renal disturbances. Among studies on the microbiome-based therapeutics, findings of probiotic effects on HE have been contradictory in spite of several supportive results. However, the effects of synbiotics and prebiotics are substantially documented. The background of their effectiveness should be evaluated again in relation to the cirrhosis-related changes in gut microbiome and their metabolic effects. Strict indications for the antibiotic rifaximin remain unestablished, although its effect is promising, improving HE and other complications with little influence on microbial populations. The final goal of microbiome-based therapeutics is to adjust the gut-liver axis to the maximal benefit of cirrhotic patients, with the aid of evolving metagenomic and metabolomic analyses.

Effect of different treatments and alcohol addiction on gut microbiota in minimal hepatic encephalopathy patients

Minimal hepatic encephalopathy (MHE) is caused by dysbiosis of gut microbiota, particularly the ammonia-producing bacteria. Given the efficacy of certain treatments on MHE and the connection between alcoholism and MHE, a thorough understanding of how these strategies affect the gut microbiota in patients (alcoholic or non-alcoholic) will facilitate the assessment of their efficacy in the reshaping of gut microbiota. In the present study, a metagenomics approach was adopted to reveal alterations in gut microbiota of 14 MHE patients following treatment with rifaximin alone or rifaximin plus probiotics. Patients were grouped into the alcoholic and non-alcoholic groups to examine differences in terms of their response to treatment. Treatment reduced the overall microbiota diversity and decreased the abundance of certain ammonia-producing bacteria, such as Clostridium, with the treatment of rifaximin plus probiotics presenting a more apparent effect. Non-alcoholic MHE patients responded better to the treatment, as they presented greater reduction in microbiota diversity and a more consistent decline in certain ammonia-producing bacteria genera (such as Clostridium and Streptococcus) belonging to the Firmicutes phylum. In conclusion, treatment with rifaximin alone and rifaximin plus probiotics exhibited a different effect in different MHE patients, decreasing the overall gut microbiota diversity to various extents and reshaping microbiota in different ways. Furthermore, non-alcoholic MHE patients responded better to treatment in microbiota alterations.

Randomized controlled trial comparing lactulose plus albumin versus lactulose alone for treatment of hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy (HE) is associated with poor prognosis and treatment of HE is primarily directed at the reduction of the blood ammonia levels. The study evaluated the efficacy and safety of albumin plus lactulose versus lactulose alone for treatment of overt HE.

METHODS

In prospective randomized controlled trial, 120 patients with overt HE were randomized in two groups: group A lactulose plus albumin (n = 60) and group B lactulose alone (n = 60). Primary end point was complete reversal of HE, and secondary end points were mortality and hospital stay.

RESULTS

A total of 120 patients (mean age 40.4 ± 9.3 years) were included in this study. Thirty-six (30%) patients were in Child-Turcotte-Pugh (CTP) class B, and 84 (70%) were in CTP Class C. Mean CTP score was 9.8 ± 2.1, and model for end-stage liver disease score was 26.1 ± 5.3. Twenty seven (22.5%) had grade 2, 57 (47.5%) had grade 3, and 36 (30%) had grade 4 HE at the time of admission. Forty-five (75%) patients in group A compared with 32 (53.3%) patients in group B had complete reversal of HE (P = 0.03). Mortality was significantly lower in lactulose plus albumin group (11[18.3%]) versus lactulose alone (19 [31.6%], [P < 0.05]). There was significant decrease in levels of arterial ammonia, interleukin-6, interleukin-18, tumor necrosis factor-alpha, and endotoxins after treatment in both groups; however, the delta decrease was significantly higher in group A compared with group B. Hospital stay was shorter in group A.

CONCLUSIONS

Combination of lactulose plus albumin is more effective than lactulose alone in treatment of overt HE.

Minimal hepatic encephalopathy in children with chronic liver disease: Prevalence, pathogenesis and magnetic resonance-based diagnosis

BACKGROUND & AIMS

Data on minimal hepatic encephalopathy (MHE) in children is scarce. We aimed to study MHE in children with chronic liver disease (CLD) and to validate non-invasive objective tests which can assist in its diagnosis.

METHODS

We evaluated 67 children with CLD (38 boys; age 13 [7-18] years) and 37 healthy children to determine the prevalence of MHE. We also assessed the correlation of MHE with changes in brain metabolites by magnetic resonance spectroscopy (¹HMRS), diffusion tensor imaging (DTI) derived metrics, blood ammonia and inflammatory cytokines (interleukin-6 [IL6], tumor necrosis factor alpha [TNF-α]). In addition, the accuracy of MR-based investigations for diagnosis of MHE in comparison to neuropsychological tests was analysed.

RESULTS

Thirty-four (50.7%) children with CLD had MHE on neuropsychological tests. MHE patients had higher BA (30.5 [6-74] vs. 14 [6-66]μmol/L; p=0.02), IL-6 (8.3 [4.7-28.7] vs. 7.6 [4.7-20.7]pg/ml; p=0.4) and TNF-α (17.8 [7.8-65.5] vs. 12.8 [7.5-35]pg/ml; p=0.06) than No-MHE. ¹HMRS showed higher glutamine (2.6 [2.1-3.3] vs. 2.4 [2.0-3.1]; p=0.02), and lower choline (0.20 [0.14-0.25] vs. 0.22 [0.17-0.28]; p=0.1) and myo-inositol (0.25 [0.14-0.41] vs. 0.29 [0.21-0.66]; p=0.2) in MHE patients than those without MHE. Mean diffusivity (MD) on DTI was significantly higher in 6/11 brain areas in patients with MHE vs. no MHE. Brain glutamine had a significant positive correlation with blood ammonia, IL-6, TNF-α and MD of various brain regions. Neuropsychological tests showed a negative correlation with blood ammonia, IL6, TNF-α, glutamine and MD. Frontal white matter MD had a sensitivity and specificity of 73.5% and 100% for diagnosing MHE.

CONCLUSIONS

In children with CLD, 50% have MHE. There is a significant positive correlation between markers of hyperammonemia, inflammation and brain edema and these correlate negatively with neuropsychological tests. MD on DTI is a reliable tool for diagnosing MHE.

LAY SUMMARY

Fifty percent of children with chronic liver disease develop minimal hepatic encephalopathy (MHE) and perform poorly on neuropsychological testing. These children have raised blood ammonia, inflammatory cytokines and mild cerebral edema on diffusion tensor imaging as compared to children without MHE. The higher the ammonia, inflammatory cytokines and cerebral edema levels the poorer the performance on neuropsychological assessment. The estimation of mean diffusivity on diffusion tensor imaging is an objective and reliable method for diagnosing MHE.

Gut Microbiota and Complications of Liver Disease

Chronic liver disease, cirrhosis, and its complications are epidemic worldwide. Most complications are mediated through a dysfunctional gut-liver axis. New techniques have made culture-independent analysis of the gut microbiome widespread. With insight into an unfavorable microbiome (dysbiosis) and how it affects liver disease, investigators have discovered new targets to potentially improve outcomes. Dysbiosis is associated with endotoxemia and propagates liver injury due to nonalcoholic steatohepatitis and alcohol. The composition and functionality of the microbiome changes with the development of cirrhosis, decompensation, and with treatments for these conditions. Gut microbiota can be used to predict clinically relevant outcomes in cirrhosis.

Minimal hepatic encephalopathy in cirrhosis- how long to treat?

INTRODUCTION

Minimal hepatic encephalopathy (MHE) can reverse after short-term treatment. However, relapse rate of MHE after stopping treatment has not been studied so far. We aimed to evaluate long-term (9 months) efficacy of a short-term (3 months) treatment of MHE with lactulose/rifaximin, for maintenance of remission from MHE.

MATERIAL AND METHODS

In this prospective study, consecutive patients with cirrhosis and MHE were treated with lactulose/rifaximin for 3 months. After treatment, they were followed up for 6 months. Psychometric testing for diagnosis of MHE was performed at baseline, 3 months and 9 months.

RESULTS

Of the 527 patients screened, 351 were found eligible and tested for MHE. Out of these, 112 (31.9%) patients had MHE (mean age 55.3 years; 75% males). They were randomized to receive Rifaximin (n = 57; 1,200 mg/day) or Lactulose (n = 55; 30-120 mL/day) for three months. At 3 months, 73.7% (42/57) patients in Rifaximin group experienced MHE reversal compared to 69.1% (38/55) in Lactulose group (p = 0.677). Six months after stopping treatment, 47.6% (20/42) in rifaximin group and 42.1% (16/38) patients in lactulose group experienced MHE relapse (p = 0.274). The overt hepatic encephalopathy development rate (7.1% vs. 7.9%) and mortality rate (0.23% vs. 0%) were similar in both groups. The Child-Turcotte-Pugh score and model for end stage liver disease (MELD) scores of patients who had MHE relapse were higher compared to those who didn't. On multivariate regression analysis, MELD score was an independent predictor of MHE relapse.

CONCLUSION

Of the patients who became MHE negative after short-term (3 months) treatment with rifaximin/lactulose, almost 50% had a relapse of MHE at 6 months follow-up.

Factors contributing to the development of overt encephalopathy in liver cirrhosis patients

The aim of this study was to clarify the relationships among psychometric testing results, blood ammonia (NH3) levels, electrolyte abnormalities, and degree of inflammation, and their associations with the development of overt hepatic encephalopathy (HE) in liver cirrhosis (LC) patients. The relationships between covert HE and blood NH3, sodium (Na), and C-reactive protein (CRP) were examined in 40 LC patients. The effects of elevated NH3, hyponatremia, and elevated CRP on the development of overt HE were also investigated. The covert HE group had significantly lower serum Na levels and significantly higher serum CRP levels. During the median observation period of 11 months, 10 patients developed overt HE, and the results of multivariate analysis showed that covert HE and elevated blood NH3 were factors contributing to the development of overt HE. Electrolyte abnormalities and mild inflammation are involved in the pathogenesis of HE. Abnormal psychometric testing results and hyperammonemia are linked to subsequent development of overt HE.

Nonabsorbable disaccharides for hepatic encephalopathy: A systematic review and meta-analysis

Nonabsorbable disaccharides (NADs) have been used to treat hepatic encephalopathy (HE) since 1966. However, a Cochrane Review, published in 2004, found insufficient evidence to recommend their use in this context. This updated systematic review evaluates the effects of the NADs, lactulose and lactitol, for the treatment and prevention of HE in patients with cirrhosis. Thirty-eight randomized controlled trials, involving 1,828 patients, were identified through electronic and manual searches; 31 randomized controlled trials looked at the treatment of HE, while seven looked at its primary/secondary prevention. Random-effects meta-analyses showed that, compared to placebo/no intervention, NADs had a beneficial effect on HE (relative risk [RR] = 0.63, 95% confidence interval [CI] 0.53-0.74, number needed to treat [NNT] = 4) and serious liver-related adverse events such as liver failure, variceal bleeding, serious infections, spontaneous bacterial peritonitis, and hepatorenal syndrome (RR = 0.42, 95% CI 0.26-0.69, NNT = 50). Treatment was also associated with a reduction in mortality in patients with overt HE (RR = 0.36, 95% CI 0.14-0.94, NNT = 20), although not in patients with minimal HE. Meta-analyses of the prevention randomized controlled trials showed that NADs prevented the development of HE (RR = 0.47, 95% CI 0.33-0.68, NNT = 6), the risk of developing serious liver-related adverse events (RR = 0.48, 95% CI 0.33-0.70, NNT = 6), and reduced mortality (RR = 0.63, 95% CI 0.40-0.98, NNT = 20). Use of NADs was associated with nonserious gastrointestinal adverse events. There were no differences in the efficacy or safety of lactulose and lactitol.

CONCLUSIONS

NADs have beneficial effects in the treatment and prevention of HE; their use, in this context, confers additional benefits including a reduction in serious liver-related morbidities and all-cause mortality. (Hepatology 2016;64:908-922).

Combined Intraperitoneal and Intrathecal Etanercept Reduce Increased Brain Tumor Necrosis Factor-Alpha and Asymmetric Dimethylarginine Levels and Rescues Spatial Deficits in Young Rats after Bile Duct Ligation

BACKGROUND

Rats subjected to bile duct ligation (BDL) exhibit increased systemic oxidative stress and brain dysfunction characteristic of hepatic encephalopathy (HE), including fatigue, neurotransmitter alterations, cognitive and motor impairment, and brain inflammation. The levels of tumor necrosis factor-alpha (TNF-α) and asymmetric dimethylarginine (ADMA) are both increased in plasma and brain in encephalopathy induced by chronic liver failure. This study first determined the temporal profiles of TNF-α and ADMA in the plasma, brain cortex, and hippocampus in young BDL rats. Next, we examined whether etanercept was beneficial in preventing brain damage.

METHODS

Young rats underwent sham ligation or BDL at day 17 ± 1 for 4 weeks. Treatment group rats were administered etanercept (10 mg/kg) intraperitoneally (IP) three times per week with or without etanercept (100 μg) intrathecally (IT) three times in total.

RESULTS

We found increased plasma TNF-α, soluble tumor necrosis factor receptor 1 (sTNFR1), soluble tumor necrosis factor receptor 2 (sTNFR2), and ADMA levels, increased cortical TNF-α mRNA and protein and ADMA, and hippocampal TNF-α mRNA and protein, and spatial defects in young BDL rats. The increase in cortex TNF-α mRNA and ADMA were reduced by IP etanercept or combined IP and IT etanercept. Dually IP/IT etanercept administration reduced the increased cortical and hippocampal TNF-α mRNA and protein level as well as spatial deficits.

CONCLUSIONS

We conclude that combined intraperitoneal and intrathecal etanercept reduce increased brain TNF-α and ADMA levels and rescues spatial deficits in young rats after BDL.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Potential targeted therapies for the inflammatory pathogenesis of hepatic encephalopathy

Hepatic encephalopathy (HE) is a severe neuropsychiatric complication of acute and chronic liver dysfunction, and is characterized by a spectrum that ranges from mild neuropsychological disturbances to coma. Although ammonia plays a critical role in the pathogenesis of HE, the plasma concentrations of ammonia and manifest symptoms of HE are not always consistent in patients with HE. Recently, a substantial body of evidence has indicated that inflammation acts in concert with ammonia in the pathogenesis of HE. Meanwhile, emerging novel and potential therapeutic strategies, including N-acetylcysteine, hypothermia, minocycline, non-steroidal anti-inflammatory drugs, tumour necrosis factor-alpha antagonists and p38 inhibitors, have been reported to ameliorate systemic inflammation and neuroinflammation, improve or reverse neuropsychiatric manifestations, and prevent the onset and progression of HE in patients and/or animal models of acute or chronic liver failure. These results point to the possible therapeutic utility of decreasing inflammation in the treatment of HE, and translation of these experimental results to the clinic may provide novel and promising therapeutic approaches for patients with HE secondary to acute or chronic liver failure. This review will provide an overview of these potential targeted therapies in the prophylaxis and treatment of HE.

Inflammation: A novel target of current therapies for hepatic encephalopathy in liver cirrhosis

Hepatic encephalopathy (HE) is a severe neuropsychiatric syndrome that most commonly occurs in decompensated liver cirrhosis and incorporates a spectrum of manifestations that ranges from mild cognitive impairment to coma. Although the etiology of HE is not completely understood, it is believed that multiple underlying mechanisms are involved in the pathogenesis of HE, and one of the main factors is thought to be ammonia; however, the ammonia hypothesis in the pathogenesis of HE is incomplete. Recently, it has been increasingly demonstrated that inflammation, including systemic inflammation, neuroinflammation and endotoxemia, acts in concert with ammonia in the pathogenesis of HE in cirrhotic patients. Meanwhile, a good number of studies have found that current therapies for HE, such as lactulose, rifaximin, probiotics and the molecular adsorbent recirculating system, could inhibit different types of inflammation, thereby improving the neuropsychiatric manifestations and preventing the progression of HE in cirrhotic patients. The anti-inflammatory effects of these current therapies provide a novel therapeutic approach for cirrhotic patients with HE. The purpose of this review is to describe the inflammatory mechanisms behind the etiology of HE in cirrhosis and discuss the current therapies that target the inflammatory pathogenesis of HE.

Reversal of Low-Grade Cerebral Edema After Lactulose/Rifaximin Therapy in Patients with Cirrhosis and Minimal Hepatic Encephalopathy

OBJECTIVES:

Decreased magnetization transfer ratio (MTR) in the brain characterizes cerebral edema (CE) in patients with liver cirrhosis, but the role of treatment on its reversibility has not been studied in patients who have minimal hepatic encephalopathy (MHE). This study was carried to evaluate the reversibility of CE with lactulose and rifaximin treatment in patients with MHE and role of ammonia, pro-inflammatory interleukins (IL-1, IL-6) and tumor necrosis factor (TNF)-α in its pathogenesis.

METHODS:

Twenty-three patients with cirrhosis (14 with MHE, 9 without MHE (NMHE)) and 6 healthy controls underwent ammonia, IL-1, IL-6, TNF-α estimation, and MTR in frontal white matter (FWM), parietal white matter (PWM), internal capsule (IC), and basal ganglia (BG).

RESULTS:

Ammonia was significantly higher in the cirrhosis group compared with controls and in MHE compared with the NMHE group. Ammonia correlated positively with IL-1 and IL-6. MTRs in FWM, PWM, IC, and BG were significantly lower in the MHE group compared with controls and in PWM, IC, and BG compared with the NMHE group. MHE patients showed significant MTR increase in FWM, PWM, and IC with treatment. IL-6 and ammonia had significant negative and significant positive psychometric hepatic encephalopathy score (PHES) correlation with MTR in various regions.

CONCLUSIONS:

This study, for the first time, demonstrated the reversibility of low-grade CE with treatment in patients with MHE. Negative correlation between ammonia, IL-6 levels, and MTR and positive correlation between PHES and MTR in MHE patients suggests the role of inflammation and ammonia in the genesis of low-grade CE.

Viability assessment of magnetic resonance spectroscopy for the detection of minimal hepatic encephalopathy severity

OBJECTIVE

To evaluate regional cerebral metabolic changes in minimal hepatic encephalopathy (MHE) patients using magnetic resonance spectroscopy (MRS) in 3T scanner.

MATERIALS AND METHODS

This study comprised 30 cirrhotic patients with MHE, 29 cirrhotic patients without MHE and 30 healthy volunteers. Single-voxel proton MRS data in the anterior cingulate cortex (ACC) and basal ganglia were acquired using a 3-T scanner. The concentrations of N-acetylaspartate (NAA), mI (myo-inositol), glutamate (Glu), glutamine (Gln) and creatine (Cr) were obtained by LC-model software. Statistical analysis was performed to evaluate the differences between the three groups.

RESULTS

There was a significant increase in Glu for the cirrhotic patients, particularly the MHE patients. There was an elevation of Gln in the cirrhotic patients, but not in all cirrhotic patients or controls. There was a significant decrease in mI for the cirrhotic patients, but no significant difference between the two cirrhosis groups. There was no significant difference in NAA between the three groups.

CONCLUSIONS

MRS using a 3-T MR scanner could detect cerebral metabolic changes in cirrhotic patients with MHE. Glu levels were elevated in cirrhotic patients with MHE; Glu levels could be used as a sensitive indicator to evaluate the severity of MHE in patients with cirrhosis.

Significance of magnetic resonance spectroscopy in diagnosis of minimal hepatic encephalopathy

AIM: To assess the value of 3T magnetic resonance spectroscopy (MRS) in the diagnosis of minimal hepatic encephalopathy (MHE).

METHODS: MRS was performed using point-resolved echo spin spectroscopy (PRESS) sequences in patients with liver cirrhosis with MHE (n = 30) and without MHE (n = 30), and age- and sex-matched healthy controls (n = 30). The choline (Cho), myo-inositol (mIns), glutamine (Glx), creatine (Cr) and N-acetylaspartate (NAA) at the left parietal lobe were determined at MRS. The metabolic ratios of Cho/Cr, mIns/Cr, Glx/Cr and NAA/Cr were calculated, and then compared among the three groups. The correlation of the cerebral metabolite ratios with venous ammonia values was also analyzed.

RESULTS: There were decreased mIns/Cr and Cho/Cr (P < 0.05) and elevated Glx/Cr (P < 0.01) in patients with MHE compared to the normal control group. There was no significant difference in NAA/Cr among the three groups. Compared with the no-MHE group, the patients with MHE showed significantly decreased mIns/Cr in the left parietal lobe (P < 0.05). No statistical correlation between metabolite ratios and venous ammonia values was found.

CONCLUSION: 3T MRS may be of value in the diagnosis of MHE and there is no statistical correlation between metabolite ratios and venous ammonia values.

Gut microbiota: its role in hepatic encephalopathy

Ammonia, a key factor in the pathogenesis of hepatic encephalopathy (HE), is predominantly derived from urea breakdown by urease producing large intestinal bacteria and from small intestine and kidneys, where the enzyme glutaminases releases ammonia from circulating glutamine. Non-culture techniques like pyrosequencing of bacterial 16S ribosomal ribonucleic acid are used to characterize fecal microbiota. Fecal microbiota in patients with cirrhosis have been shown to alter with increasing Child-Turcotte-Pugh (CTP) and Model for End stage Liver Disease (MELD) scores, and with development of covert or overt HE. Cirrhosis dysbiosis ratio (CDR), the ratio of autochthonous/good bacteria (e.g. Lachnospiraceae, Ruminococcaceae and Clostridiales) to non-autochthonous/pathogenic bacteria (e.g. Enterobacteriaceae and Streptococcaceae), is significantly higher in controls and patients with compensated cirrhosis than patients with decompensated cirrhosis. Although their stool microbiota do not differ, sigmoid colonic mucosal microbiota in liver cirrhosis patients with and without HE, are different. Linkage of pathogenic colonic mucosal bacteria with poor cognition and inflammation suggests that important processes at the mucosal interface, such as bacterial translocation and immune dysfunction, are involved in the pathogenesis of HE. Fecal microbiome composition does not change significantly when HE is treated with lactulose or when HE recurs after lactulose withdrawal. Despite improving cognition and endotoxemia as well as shifting positive correlation of pathogenic bacteria with metabolites, linked to ammonia, aromatic amino acids and oxidative stress, to a negative correlation, rifaximin changes gut microbiome composition only modestly. These observations suggest that the beneficial effects of lactulose and rifaximin could be associated with a change in microbial metabolic function as well as an improvement in dysbiosis.

Management of covert hepatic encephalopathy

Hepatic encephalopathy is a reversible progressive neuropsychiatric disorder that encompasses a wide clinical spectrum. Covert hepatic encephalopathy is defined as patients with minimal hepatic encephalopathy and Grade I encephalopathy by West-Haven Criteria. Terminology such as "sub-clinical", "latent", and "minimal" appear to trivialize the disease and have been replaced by the term covert. The lack of clinical signs means that covert hepatic encephalopathy is rarely recognized or treated outside of clinical trials with options for therapy based on patients with episodic hepatic encephalopathy. This review discusses the current available options for therapy in covert hepatic encephalopathy and focuses on non-absorbable disacharides (lactulose or lactitol), antibiotics (rifaximin), probiotics/synbiotics and l-ornithine-l-aspartate.

Diagnosis of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (mHE) has significant impact upon a liver patient's daily living and health related quality of life. Therefore a majority of clinicians agree that mHE should be diagnosed and treated. The optimal means for diagnosing mHE, however, is controversial. This paper describes the currently most frequently used methods-EEG, critical flicker frequency, Continuous Reaction time Test, Inhibitory Control Test, computerized test batteries such as the Cognitive Drug Research test battery, the psychometric hepatic encephalopathy score (PHES) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)-and their pros and cons.

Enhancement of functional connectivity, working memory and inhibitory control on multi-modal brain MR imaging with Rifaximin in Cirrhosis: implications for the gut-liver-brain axis

Minimal hepatic encephalopathy (MHE) impairs daily functioning in cirrhosis, but its functional brain impact is not completely understood. To evaluate the effect of rifaximin, a gut-specific antibiotic, on the gut-liver-brain axis in MHE.

HYPOTHESIS

Rifaximin will reduce endotoxemia, enhance cognition, increase activation during working memory(N-back) and reduce activation needed for inhibitory control tasks.

METHODS

Cirrhotics with MHE underwent baseline endotoxin and cognitive testing, then underwent fMRI, diffusion tensor imaging and MR spectroscopy(MRS). On fMRI, two tasks; N-back (outcome: correct responses) and inhibitory control tests(outcomes: lure inhibition) were performed. All procedures were repeated after 8 weeks of rifaximin. RESULTS were compared before/after rifaximin.

RESULTS

20 MHE patients (59.7 years) were included; sixteen completed pre/post-rifaximin scanning with 92% medication compliance. Pre-rifaximin patients had cognitive impairment. At trial-end, there was a significantly higher correct 2-back responses, ICT lure inhibitions and reduced endotoxemia(p = 0.002). This was accompanied by significantly higher activation from baseline in subcortical structures (thalamus, caudate, insula and hippocampus) and left parietal operculum (LPO) during N-back, decrease in fronto-parietal activation required for inhibiting lures, including LPO during ICT compared to baseline values. Connectivity studies in N-back showed significant shifts in linkages after therapy in fronto-parietal regions with a reduction in fractional anisotropy (FA) but not mean diffusivity (MD), and no change in MRS metabolites at the end of the trial. A significant improvement in cognition including working memory and inhibitory control, and fractional anisotropy without effect on MD or MRS, through modulation of fronto-parietal and subcortical activation and connectivity was seen after open-label rifaximin therapy in MHE.

Progress in diagnosis of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is defined as HE without symptoms on clinical/neurological examination, but with deficits in some cognitive areas that can only be measured by neuropsychometric testing. MHE is associated with reduced quality of working, driving, memory, and cognitive function, and is a risk factor for the development of overt HE. Compared with non-MHE patients, MHE patients have a high mortality rate, so positive screening and intervention in patients with MHE are needed to improve the quality of life in patients with cirrhosis and reduce traffic accidents and the social burden of medical care. The current approach to the diagnosis of MHE includes mental scales (paper pencil test, computer test, or the combination of the two), electrophysiological examination, and imaging examination. Diagnosis of MHE is still a challenge now, and it is needed to establish a better clinical diagnosis standard to improve the diagnostic level.

Zingerone suppresses liver inflammation induced by antibiotic mediated endotoxemia through down regulating hepatic mRNA expression of inflammatory markers in Pseudomonas aeruginosa peritonitis mouse model

Antibiotic-induced endotoxin release is associated with high mortality rate even when appropriate antibiotics are used for the treatment of severe infections in intensive care units. Since liver is involved in systemic clearance and detoxification of endotoxin hence it becomes a primary target organ for endotoxin mediated inflammation. Currently available anti-inflammatory drugs give rise to serious side effects. Hence, there is an urgent need for safe and effective anti-inflammatory therapy. It is likely that anti-inflammatory phytochemicals and neutraceutical agents may have the potential to reduce the endotoxin mediated inflammation and complications associated with endotoxin release. Keeping this in mind, the present study was planned to evaluate the hepatoprotective potential of zingerone (active compound of zingiber officinale) against liver inflammation induced by antibiotic mediated endotoxemia. The selected antibiotics capable of releasing high content of endotoxin were employed for their in vivo efficacy in P.aeruginosa peritonitis model. Released endotoxin induced inflammation and zingerone as co-anti-inflammatory therapy significantly reduced inflammatory response. Improved liver histology and reduced inflammatory markers MDA, RNI, MPO, tissue damage markers (AST, ALT, ALP) and inflammatory cytokines (MIP-2, IL-6 and TNF-α) were indicative of therapeutic potential of zingerone. The mechanism of action of zingerone may be related to significant inhibition of the mRNA expression of inflammatory markers (TLR4, RelA, NF-kB2, TNF- α, iNOS, COX-2) indicating that zingerone interferes with cell signalling pathway and suppresses hyper expression of cell signaling molecules of inflammatory pathway. Zingerone therapy significantly protected liver from endotoxin induced inflammatory damage by down regulating biochemical as well as molecular markers of inflammation. In conclusion, this study provides evidence that zingerone is a potent anti-inflammatory phytomedicine against hepatic inflammation induced by antibiotic mediated endotoxemia. These results thus suggest that zingerone treatment can be used as a co-therapy with antibiotics to reduced endotoxin induced inflammation during treatment of severe P.aeruginosa infections.

Dietary management of hepatic encephalopathy revisited

PURPOSE OF REVIEW

The burden of hepatic encephalopathy on health services is increasing, and some degree of consensus in relation to drug therapy and prophylaxis has been reached. This review focuses on the role of nutritional interventions in the management of hepatic encephalopathy.

RECENT FINDINGS

A number of relatively new pieces of evidence are emerging in relation to nutrition and hepatic encephalopathy as follows: first, reduction of protein intake is not useful for hepatic encephalopathy, but protein selection should be considered; second, oral supplementation with branched chain amino acids has a role not only for its nutritional effect in cirrhosis per se, but also for its effect in reducing the risk of recurrence of hepatic encephalopathy; third, alterations in gut microbiota develop in parallel with decompensation of cirrhosis, and modulation of gut microbiota may be effective for treating and preventing hepatic encephalopathy; fourth, prebiotics and probiotics are potentially useful in this aim, thus further research or trials on prebiotics and probiotics are required; fifth, micronutrient deficiency, which is common in end-stage liver disease, has adverse effects on the brain and may either directly cause encephalopathy per se, or interact with the mechanisms leading to hepatic encephalopathy.

SUMMARY

Properly performed nutritional interventions are likely to be useful for patients with hepatic encephalopathy, but well conducted clinical trials are required.

VIDEO ABSTRACT

http://links.lww.com/COCN/A7.