Clinical and Neurologic Manifestation of Minimal Hepatic Encephalopathy and Overt Hepatic Encephalopathy

Transcriptome Profile in the Mouse Brain of Hepatic Encephalopathy and Alzheimer's Disease

Hepatic encephalopathy (HE) is a chronic metabolic disease accompanied by neuropathological and neuropsychiatric features, including memory deficits, psychomotor dysfunction, depression, and anxiety. Alzheimer's disease (AD), the most common neurodegenerative disease, is characterized by tau hyperphosphorylation, excessive amyloid beta (Aβ) accumulation, the formation of fibrillary tangles, hippocampus atrophy, and neuroinflammation. Recent studies have suggested a positive correlation between HE and AD. Some studies reported that an impaired cholesterol pathway, abnormal bile acid secretion, excessive ammonia level, impaired Aβ clearance, astrocytic dysfunction, and abnormal γ-aminobutyric acid GABAergic neuronal signaling in HE may also be involved in AD pathology. However, the mechanisms and related genes involved in AD-like pathology in the HE brain are unclear. Thus, we compared the cortical transcriptome profile between an HE mouse model, bile duct ligation (BDL), and an AD mouse model, the 5×FAD. Our study showed that the expression of many genes implicated in HE is associated with neuronal dysfunction in AD mice. We found changes in various protein-coding RNAs, implicated in synapses, neurogenesis, neuron projection, neuron differentiation, and neurite outgrowth, and non-coding RNAs possibly associated with neuropathology. Our data provide an important resource for further studies to elucidate AD-like pathophysiology in HE patients.

Clinical efficiency of inhibitory control test for the diagnosis of minimal hepatic encephalopathy: A systematic review with meta-analysis

AIM

Minimal hepatic encephalopathy (MHE) is a common neuropsychiatric complication of liver cirrhosis and portosystemic shunt. The inhibitory control test (ICT) is a novel computerized psychometric test for MHE diagnosis, but its efficiency has yet to be confirmed. This study aimed to systematically review the existing evidence concerning the ICT application and then evaluate the efficiency of ICT for MHE diagnosis in clinical practice.

METHODS

A comprehensive search of published works was carried out to identify reports concerning the ICT for MHE diagnosis between January 2000 and December 2020. The pooled sensitivity, specificity, and diagnostic odds ratio of ICT for MHE diagnosis were calculated using a random or fixed effect model. The summary receiver operator characteristic (sROC) curve was constructed, and the area under the sROC curve was calculated. Metaregression and subgroup analyses were used to identify the source of heterogeneity. Publication bias was evaluated using the Deeks funnel plot asymmetry test.

RESULTS

Twelve studies were included in this systematic review, and nine studies enrolling 1022 patients were included in the final meta-analysis. The ICT had a pooled sensitivity, specificity, and DOR of 83%, 64%, and 9, respectively. The area under the sROC curve was 0.79. The metaregression analysis indicated that different locations of studies (relative diagnostic odds ratio, 12.65; p = 0.02) were identified as the source of heterogeneity. No significant publication bias was observed.

CONCLUSIONS

The ICT has a high sensitivity and moderate specificity for MHE diagnosis, and it can be used as a primary diagnostic method for MHE.

Therapeutic dilemma: alcohol withdrawal syndrome and concurrent hepatic encephalopathy. A case report

Alcohol use disorder is one of the main causes of morbidity and mortality in the world. Alcoholic liver disease is a common complication of this disorder, and hepatic encephalopathy is a serious complication of alcoholic cirrhosis. Precipitating factors may be related to infection, gastrointestinal bleeding, dehydration or the effects of psychotropic drugs (e.g. benzodiazepines and non-benzodiazepine hypnotics). We present a case of the hospital management of a patient with a severe alcohol use disorder, cirrhosis and hepatic encephalopathy who developed alcohol withdrawal symptoms while in hospital, and discuss the complexity of the antagonistic management of a GABAergic delirium characteristic of hepatic encephalopathy in the context of a glutamatergic-noradrenergic delirium due to alcohol withdrawal.

Comprehensive Overview of Sleep Disorders in Patients with Chronic Liver Disease

The impact of sleep disorders (SDs) on patients with chronic liver diseases (CLD) is tremendous. SDs are frequently encountered among these patients and interfere with their quality of life. This review aims to present the data available so far about the prevalence, phenotypes, and proposed pathophysiological mechanisms of SDs in CLD. Moreover, we proposed to search the literature regarding the most reliable methods to assess SDs and the possible therapeutic options in patients with CLD. The main results of this review show that when it comes to prevalence, the percentages reported vary widely between studies performed among populations from the USA or Europe and those coming from Asian countries. Furthermore, it has been proven that SDs may also be present in the absence of neurocognitive disorders attributable to hepatic encephalopathy (HE), which contradicts traditional suppositions where SDs were considered part of the clinical scenario of HE. Currently, there are no specific recommendations or protocols to assess SDs in CLD patients and data about the therapeutic management are limited. Taking into consideration their impact, a protocol for diagnosing and managing SDs should be developed and included in the daily practice of hepatologists.

Novel computerized psychometric tests as primary screening tools for the diagnosis of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is a critical neurocognitive complication of decompensated liver cirrhosis and portosystemic shunting, which results in a wide range of cognitive deficits including impairments in working attention, psychomotor speed, and executive function. Current guidelines have recommended paper-and-pencil psychometric tests for the diagnosis of MHE. Most high-risk cirrhotic patients are required to be examined; however, paper-and-pencil psychometric tests are neither convenient nor rapid to perform in the clinic. Recently, novel computerized psychometric tests, including the inhibitory control test, EncephalApp Stroop App, and critical flicker frequency, have been proven to be rapid, effective, and convenient methods for screening MHE in clinical practice and for identifying high-risk cirrhotic patients for further validation using rigid neuropsychometric examinations. However, diagnostic accuracy of these tests is influenced by educational background, age, and cultural differences. This review summarizes clinical evidence of the application of novel computerized psychometric tests for screening MHE.

Animal Naming Test - a simple and accurate test for diagnosis of minimal hepatic encephalopathy and prediction of overt hepatic encephalopathy

Aim of the study

Minimal hepatic encephalopathy (MHE) is the mildest form in the spectrum of hepatic encepha-lopathy (HE). We compared the usefulness of the Psychometric Hepatic Encephalopathy Score (PHES) and Animal Naming Test (ANT) for the diagnosis of MHE and the prediction of the development of overt episodes of HE.

Material and methods

103 consecutive patients with liver cirrhosis without overt HE were subjected to PHES and ANT evaluation. The receiver-operating characteristic curve was used to determine the optimum cut-off of the ANT value for the diagnosis of MHE.

Results

Thirty-seven (35.9%) patients had MHE as assessed by altered PHES. ANT (< 14) was positive in 36 (34.95%) patients with MHE with a sensitivity of 89.19% and specificity of 95.7%, positive predictive value (PPV) of 91.67%, negative predictive value (NPV) of 94.03% and diagnostic accuracy of 93.20%. The area under the curve for diagnosis of MHE was 0.978 (95% CI: 0.954-1.0). MHE patients had significantly lower ANT as compared to non-MHE patients and controls (10.81 ±0.324 vs. 15.27 ±0.147 vs. 15.78 ±0.192, respectively, p = 0.01). ANT correlated with PHES (r = 0.752, p = 0.001) and also with Child-Pugh (r = –0.408, p = 0.001) and MELD (r = –0.318, p = 0.001) scores. During follow-up, 14 patients in the MHE group and 4 in the non-MHE group developed overt episodes of HE (p = 0.001).

Conclusions

ANT is simple and accurate for the diagnosis of MHE and prediction of overt episodes of HE in patients with cirrhosis and correlates well with the Child-Pugh and MELD scores.

Clinical Manifestations of Hepatic Encephalopathy

Hepatic encephalopathy (HE) occurs in patients with acute-on-chronic liver disease. It has a wide progression of symptoms, with its initial presentation being subtle. The symptoms of HE mainly affect mental status, the musculoskeletal system, and mood/behavior. Its severity ranges from minor disturbances in sleep-wake cycle to the patient being comatose. HE is categorized based on 4 main features: the underlying disease, the severity of manifestations, the time course, and whether precipitating factors are present. The severity of the manifestations is classically identified using the West Haven Criteria. There are several other clinical tests, but they require further validation.

EncephalApp Stroop App predicts poor sleep quality in patients with minimal hepatic encephalopathy due to hepatitis B-induced liver cirrhosis

BACKGROUND/AIM

A novel computerised Stroop test- EncephalApp Stroop App (EncephalApp) has good diagnostic validity for minimal hepatic encephalopathy (MHE) in cirrhotic patients. The Stroop test is correlated with sleep disturbances which are common, and severely affects health-related quality of life in cirrhotic patients with MHE. We evaluated the relationship between sleep quality and EncephalApp results in patients with MHE due to hepatitis B-induced liver cirrhosis.

PATIENTS AND METHODS

We enrolled 180 adult patients with hepatitis B-induced cirrhosis. All patients were tested using the psychometric hepatic encephalopathy score (PHES) and EncephalApp. We analysed the diagnostic validity of EncephalApp for MHE using PHES as the gold standard for reference. The sleep quality of included patients was evaluated using the Pittsburgh Sleep Quality Index (PSQI). The predictive factors for poor sleep quality were analysed using backwards conditional stepwise logistic regression analysis.

RESULTS

Ninety-eight patients (54.4%) were diagnosed with MHE by PHES. Receiver operating characteristic (ROC) curve analysis showed that the threshold value of EncephalApp for MHE diagnosis was 225.60 s. EncephalApp showed 85.2% sensitivity and 77.3% specificity for diagnosing MHE; the area under the ROC curve was 0.864. PSQI scores of cirrhotic patients with MHE were significantly lower than those without MHE (P < 0.05). Child Turcotte Pugh grades (Odds ratio [OR] = 2.11 [1.55-2.85], P < 0.01) and the total Off-time plus On-time of EncephalApp (OR = 4.14 [1.95-6.29], P < 0.01) were independent predictors of poor sleep quality in MHE patients.

CONCLUSIONS

The total Off-time plus On-time of EncephalApp predicts poor sleep quality in patients with MHE due to hepatitis B-induced cirrhosis.

Bile duct ligation of C57BL/6 mice as a model of hepatic encephalopathy

Background

Bile duct ligation (BDL) has been used for experimental research on hepatic encephalopathy (HE) caused by chronic liver disease. However, little research has been done on a BDL model in C57BL/6 mouse. Therefore, we evaluated the suitability of a BDL model in C57BL/6 mouse for the study of HE and determined which behavioral tests are appropriate for the identification of HE in this model.

Methods

Twelve to fourteen-week-old male C57BL/6 mice were randomly assigned to either sham group or BDL group. Histological changes in liver were confirmed by hematoxylin/eosin and Masson’s trichrome staining. Liver function alterations were detected by alanine aminotransferase (ALT) and ammonia levels. To identify behavioral changes, open field, elevated plus maze, novel object recognition, and passive avoidance tests were performed.

Results

Inflammatory liver injury and fibrosis were observed 14 days after BDL. ALT and ammonia levels were significantly higher in BDL group than in sham group. There were no differences in general locomotor activity or anxiety between the groups. No difference was observed between these two groups in the novel object recognition test, but BDL group showed significant learning/memory impairment in the passive avoidance test compared to sham group.

Conclusions

Fourteen days of BDL in 12–14-week-old male C57BL/6 mice is a clinically relevant model for HE, as these mice have liver fibrosis with impaired liver function, hyperammonemia, and learning/memory impairment. Passive avoidance can be used as the major behavioral test in this model of HE.

Advances in psychometric tests for screening minimal hepatic encephalopathy: From paper-and-pencil to computer-aided assessment

Minimal hepatic encephalopathy (MHE) is a major neuropsychiatric complication of liver cirrhosis and portosystemic shunting. Although MHE produces a spectrum of cognitive impairments in the domains of short-term attention, working memory, and executive function, it generally does not present with obvious clinical manifestation on conventional assessments. Paper-and-pencil psychometric tests, such as the psychometric hepatic encephalopathy score and the repeatable battery for the assessment of neuropsychological status, are recommended to diagnose MHE. However, these tests are neither rapid nor convenient to use in practice. To facilitate repeated testing in clinic and follow-up, computer-aided psychometric tests, such as the scan test, Cognitive Drug Research assessment battery, inhibitory control test, EncephalApp Stroop App, and critical flicker frequency, have been used to screen for MHE among patients with liver cirrhosis. The aim of this review was to describe the progression from the utility of paper-and-pencil to computer-aided psychometric tests for MHE screening in clinical practice.

Minimal hepatic encephalopathy: current clinical and pathogenetic aspects

The review considers modern ideas about the clinic and pathogenesis of minimal hepatic encephalopathy (MHE). It is discussed the present of cognitive impairment in this category of patients. The data of functional MRI are analyzed, and these results allow taking a fresh look at the origin of clinical disorders in this condition. The importance of cerebral connections disruption is emphasized. It is focused on the fact that in the functioning of the central nervous system the spontaneous activity of the brain has a significant importance. Separately is analyzed "the resting state". It is concluded that MHE, despite its minimal manifestations, is a clinically significant condition requiring attention of a specialists. With that, it is often not diagnosed on time in clinical practice, which could lead to more severe damage of the cerebral functions. As evidenced by the data obtained at the present time, quite extensive changes in the neuronal activity are underlid of the cognitive deficit.

Increasing Burden of Hepatic Encephalopathy Among Hospitalized Adults: An Analysis of the 2010-2014 National Inpatient Sample

BACKGROUND

Hepatic encephalopathy (HE) is associated with substantial morbidity and mortality, contributing significant burden on healthcare systems.

AIM

We aim to evaluate trends in clinical and economic burden of HE among hospitalized adults in the USA.

METHODS

Using the 2010-2014 National Inpatient Sample, we identified adults hospitalized with HE using ICD-9-CM codes. Annual trends in hospitalizations with HE, in-hospital mortality, and hospital charges were stratified by the presence of acute liver failure (ALF) or cirrhosis. Adjusted multivariable regression models were evaluated for predictors of in-hospital mortality and hospitalization charges.

RESULTS

Among 142,860 hospitalizations with HE (mean age 59.3 years, 57.8% male), 67.7% had cirrhosis and 3.9% ALF. From 2010 to 2014, total number of hospitalizations with HE increased by 24.4% (25,059 in 2010 to 31,182 in 2014, p < 0.001). Similar increases were seen when stratified by ALF (29.7% increase) and cirrhosis (29.7% increase). Overall in-hospital mortality decreased from 13.4% (2010) to 12.3% (2014) (p = 0.001), with similar decreases observed in ALF and cirrhosis. Total inpatient charges increased by 46.0% ($8.15 billion, 2010 to $11.9 billion, 2014). On multivariable analyses, ALF was associated with significantly higher odds of in-hospital mortality (OR 5.37; 95% CI 4.97-5.80; p < 0.001) as well as higher mean inpatient charges (122.6% higher; 95% CI + 115.0-130.3%; p < 0.001) compared to cirrhosis. The presence of ascites, hepatocellular carcinoma, and hepatorenal syndrome was associated with increased mortality.

CONCLUSIONS

The clinical and economic burden of hospitalizations with HE in the USA continues to rise. In 2014, estimated national economic burden of hospitalizations with HE reached $11.9 billion.

Hepatic encephalopathy: Lessons from preclinical studies

Hepatic encephalopathy (HE) is a major complication that is closely related to the progression of end-stage liver disease. Metabolic changes in advanced liver failure can promote cognition impairment, attention deficits and motor dysfunction that may result in coma and death. HE can be subdivided according to the type of hepatic injury, namely, type A, which results from acute liver failure, type B, which is associated with a portosystemic shunting without intrinsic liver disease, and type C, which is due to chronic liver disease. Several studies have investigated the pathogenesis of the disease, and most of the mechanisms have been explored using animal models. This article aimed to review the use of preclinical models to investigate HE. The most used animal species are rats and mice. Experimental models of type A HE include surgical procedures and the administration of hepatotoxic medications, whereas models of types B and C HE are generally surgically induced lesions in liver tissue, which evolve to hepatic cirrhosis. Preclinical models have allowed the comprehension of the pathways related to HE.

Acetyl-L-carnitine for patients with hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy is a common and devastating neuropsychiatric complication of acute liver failure or chronic liver disease. Ammonia content in the blood seems to play a role in the development of hepatic encephalopathy. Treatment for hepatic encephalopathy is complex. Acetyl-L-carnitine is a substance that may reduce ammonia toxicity. This review assessed the benefits and harms of acetyl-L-carnitine for patients with hepatic encephalopathy.

OBJECTIVES

To assess the benefits and harms of acetyl-L-carnitine for patients with hepatic encephalopathy.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, and Science Citation Index Expanded for randomised clinical trials. We sought additional randomised clinical trials from the World Health Organization Clinical Trials Search Portal and ClinicalTrials.gov. We performed all electronic searches until 10 September 2018. We looked through the reference lists of retrieved publications and review articles, and we searched the FDA and EMA websites.

SELECTION CRITERIA

We searched for randomised clinical trials in any setting, recruiting people with hepatic encephalopathy. Trials were eligible for inclusion if they compared acetyl-L-carnitine plus standard care (e.g. antibiotics, lactulose) versus placebo or no acetyl-L-carnitine plus standard care. We are well aware that by selecting randomised clinical trials, we placed greater focus on potential benefits than on potential harms.

DATA COLLECTION AND ANALYSIS

We selected randomised clinical trials, assessed risk of bias in eight domains, and extracted data in a duplicate and independent fashion. We estimated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes. We measured statistical heterogeneity using I² and D² statistics. We subjected our analyses to fixed-effect and random-effects model meta-analyses. We assessed bias risk domains to control systematic errors. We assessed overall quality of the data for each individual outcome by using the GRADE approach.

MAIN RESULTS

We identified five randomised clinical trials involving 398 participants. All trials included only participants with cirrhosis as the underlying cause of hepatic encephalopathy. Trials included participants with covert or overt hepatic encephalopathy. All trials were conducted in Italy by a single team and assessed acetyl-L-carnitine compared with placebo. Oral intervention was the most frequent route of administration. All trials were at high risk of bias and were underpowered. None of the trials were sponsored by the pharmaceutical industry.None of the identified trials reported information on all-cause mortality, serious adverse events, or days of hospitalisation. Only one trial assessed quality of life using the Short Form (SF)-36 scale (67 participants; very low-quality evidence). The effects of acetyl-L-carnitine compared with placebo on general health at 90 days are uncertain (MD -6.20 points, 95% confidence interval (CI) -9.51 to -2.89). Results for additional domains of the SF-36 are also uncertain. One trial assessed fatigue using the Wessely and Powell test (121 participants; very low-quality evidence). The effects are uncertain in people with moderate-grade hepatic encephalopathy (mental fatigue: MD 0.40 points, 95% CI -0.21 to 1.01; physical fatigue: MD -0.20 points, 95% CI -0.92 to 0.52) and mild-grade hepatic encephalopathy (mental fatigue: -0.80 points, 95% CI -1.48 to -0.12; physical fatigue: 0.20 points, 95% CI -0.72 to 1.12). Meta-analysis showed a reduction in blood ammonium levels favouring acetyl-L-carnitine versus placebo (MD -13.06 mg/dL, 95% CI -17.24 to -8.99; 387 participants; 5 trials; very low-quality evidence). It is unclear whether acetyl-L-carnitine versus placebo increases the risk of non-serious adverse events (8/126 (6.34%) vs 3/120 (2.50%); RR 2.51, 95% CI 0.68 to 9.22; 2 trials; very low-quality evidence). Overall, adverse events data were poorly reported and harms may have been underestimated.

AUTHORS' CONCLUSIONS

This Cochrane systematic review analysed a heterogeneous group of five trials at high risk of bias and with high risk of random errors conducted by only one research team. We assessed acetyl-L-carnitine versus placebo in participants with cirrhosis with covert or overt hepatic encephalopathy. Hence, we have no data on the drug for hepatic encephalopathy in acute liver failure. We found no information about all-cause mortality, serious adverse events, or days of hospitalisation. We found no clear differences in effect between acetyl-L-carnitine and placebo regarding quality of life, fatigue, and non-serious adverse events. Acetyl-L-carnitine reduces blood ammonium levels compared with placebo. We rated all evidence as of very low quality due to pitfalls in design and execution, inconsistency, small sample sizes, and very few events. The harms profile for acetyl-L-carnitine is presently unclear. Accordingly, we need further randomised clinical trials to assess acetyl-L-carnitine versus placebo conducted according to the SPIRIT statements and reported according to the CONSORT statements.

Recent advances in hepatic encephalopathy

Hepatic encephalopathy describes the array of neurological alterations that occur during acute liver failure or chronic liver injury. While key players in the pathogenesis of hepatic encephalopathy, such as increases in brain ammonia, alterations in neurosteroid levels, and neuroinflammation, have been identified, there is still a paucity in our knowledge of the precise pathogenic mechanism. This review gives a brief overview of our understanding of the pathogenesis of hepatic encephalopathy and then summarizes the significant recent advances made in clinical and basic research contributing to our understanding, diagnosis, and possible treatment of hepatic encephalopathy. A literature search using the PubMed database was conducted in May 2017 using "hepatic encephalopathy" as a keyword, and selected manuscripts were limited to those research articles published since May 2014. While the authors acknowledge that many significant advances have been made in the understanding of hepatic encephalopathy prior to May 2014, we have limited the scope of this review to the previous three years only.