Minimal hepatic encephalopathy. ACTA ACUST UNITED AC. 2007;4:677-685. [PMID: 18043677 DOI: 10.1038/ncpgasthep0999]

Anti-inflammatory strategies for hepatic encephalopathy: preclinical studies

Hepatic encephalopathy (HE) is a potentially reversible neuropsychiatric syndrome. Often, HE causes cognitive and motor dysfunctions due to an acute or chronic insufficiency of the liver or a shunting between the hepatic portal vein and systemic vasculature. Liver damage induces peripheral changes, such as in the metabolism and peripheral inflammatory responses that trigger exacerbated neuroinflammation. In experimental models, anti-inflammatory strategies have demonstrated neuroprotective effects, leading to a reduction in HE-related cognitive and motor impairments. In this scenario, a growing body of evidence has shown that peripheral and central nervous system inflammation are promising preclinical targets. In this review, we performed an overview of FDA-approved drugs and natural compounds which are used in the treatment of other neurological and nonneurological diseases that have played a neuroprotective role in experimental HE, at least in part, through anti-inflammatory mechanisms. Despite the exciting results from animal models, the available data should be critically interpreted, highlighting the importance of translating the findings for clinical essays.

Altered Spontaneous Brain Activity in Cirrhotic Patients with Minimal Hepatic Encephalopathy: A Meta-Analysis of Resting-State Functional Imaging

(1) Background: Minimal hepatic encephalopathy (MHE) is an important complication of decompensated cirrhosis. Previous studies have demonstrated spontaneous brain activity alterations in cirrhotic patients with MHE. However, the reported results are inconsistent, which has limited our understanding of the potential neural mechanisms. Thus, we conducted a quantitative meta-analysis of resting-state functional imaging studies to identify the regional activity alterations consistently involved in MHE. (2) Methods: We searched six databases to include resting-state functional imaging studies and compared spontaneous brain activity patterns between MHE patients and healthy controls (HCs), and between cirrhotic patients without minimal hepatic encephalopathy (NMHE) and HCs. Then, a separate whole-brain voxel-wise meta-analysis between MHE or NMHE patients and HCs was conducted using seed-based d mapping with permutation of subject images. We further conducted the conjunction analysis to assess the distinct regional activity alterations between MHE and NMHE patients as compared to HCs. (3) Results: Thirteen studies with twenty datasets were included in this meta-analysis. Compared with HCs, MHE patients showed decreased spontaneous brain activity in the left superior frontal gyrus, left median cingulate/paracingulate gyri, and right precuneus. Compared with NMHE patients, MHE patients indicated decreased spontaneous brain activity in the left superior frontal gyrus, left median cingulate/paracingulate gyri, and right precuneus. (4) Conclusions: MHE is associated with spontaneous brain activity alterations involving the left superior frontal gyrus and median cingulate/paracingulate gyri, which may implicate primarily in spatial working memory and emotional disorders. These findings may contribute to a better understanding of the potential neural mechanisms, and guide further research.

The Role of Gut Microbiota in Mice With Bile Duct Ligation-Evoked Cholestatic Liver Disease-Related Cognitive Dysfunction

The pathogenesis of Hepatic Encephalopathy (HE) is complex and multifactorial. The development of metagenomics sequencing technology led to show the significant role of gut microbiota in the pathogenesis of cognitive dysfunction, which paved the way for further research in this field. However, it is unknown whether gut microbiota plays a role in bile duct ligation (BDL)-evoked cholestatic liver disease-related cognitive dysfunction. The aim of this investigation is to assess BDL mice induced cognitive dysfunction and meanwhile to delineate the alteration of gut microbiota in cognitive dysfunction mice, which may underline the role of gut microbiota in BDL mice induced cognitive dysfunction. Our study was carried out in male C57BL/6 J mice with bile duct ligation. The liver functions were assessed via different biochemical markers [alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBIL), and total bile acid (TBA)] and a histopathological examination of the liver tissue. We used the novel object recognition test (NORT) to assess cognitive dysfunction. And BDL mice were divided into BDL with cognitive dysfunction (BDL-CD) or BDL without cognitive dysfunction (BDL-NCD groups) by the result of hierarchical cluster analysis of NORT. Then, 16S ribosomal RNA (rRNA) gene sequencing was used to compare the gut bacterial composition between BDL-CD and BDL-NCD groups. According to our results, we concluded that bile duct ligation can significantly change the gut microbiota composition, and Bacteroides fragilis, Bacteroides ovatus V975, and Bacteroides thetaiotaomicron play a vital role in BDL-evoked cholestatic liver disease-related cognitive dysfunction.

The Pathobiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Case for Neuroglial Failure

Although myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has a specific and distinctive profile of clinical features, the disease remains an enigma because causal explanation of the pathobiological matrix is lacking. Several potential disease mechanisms have been identified, including immune abnormalities, inflammatory activation, mitochondrial alterations, endothelial and muscular disturbances, cardiovascular anomalies, and dysfunction of the peripheral and central nervous systems. Yet, it remains unclear whether and how these pathways may be related and orchestrated. Here we explore the hypothesis that a common denominator of the pathobiological processes in ME/CFS may be central nervous system dysfunction due to impaired or pathologically reactive neuroglia (astrocytes, microglia and oligodendrocytes). We will test this hypothesis by reviewing, in reference to the current literature, the two most salient and widely accepted features of ME/CFS, and by investigating how these might be linked to dysfunctional neuroglia. From this review we conclude that the multifaceted pathobiology of ME/CFS may be attributable in a unifying manner to neuroglial dysfunction. Because the two key features - post exertional malaise and decreased cerebral blood flow - are also recognized in a subset of patients with post-acute sequelae COVID, we suggest that our findings may also be pertinent to this entity.

Cognitive impairment in recipients of liver transplantation and relation to hepatic encephalopathy

Background

Liver transplantation (LT) helped to save the life of end stage liver disease (ESLD) patients; however, there is a debate on the persistence of cognitive impairment. The study aimed to evaluate cognitive functions in patients with ESLD before and after liver transplantation and to assess its relation to hepatic encephalopathy (HE). Thirty recipients 47.6 ± 11 years undergone living donor liver transplantation at the transplantation center of both Ain Shams Center for Organ Transplant and Egypt air organ transplant unit were prospectively assessed by Trail Making Test, Wechsler Memory Scale–Revised, Benton Visual Retention—for the evaluation of cognitive functions before and 3 months after transplantation.

Results

The mean age of the patients was 47.6 ± 11 years, 17 males and 13 females. Eight out of 30 (26.7%) had past history of hepatic encephalopathy. The study reported significant improvement in the post-operative 3 months scores of Trail Making Test part (A), the digit span forward test, digit span backward test and the correct score difference of the Benton Visual Retention, as p value was (0.02), (0.01) (0.02), and (0.01) respectively, compared to the pre-operative scores. However, there was no difference in the scores of part (B), verbal association I, II, information subtest of WMS. Cognitive performance showed no significant difference between patients with or without history of HE.

Conclusions

Patients with ESLD have significant cognitive impairment that showed improvement after LT; HE did not correlate with cognitive function. Hence, transplantation has a favorable outcome on the cognitive impairment.

Hepatic encephalopathy and depression in chronic liver disease: is the common link systemic inflammation?

Hepatic encephalopathy and depression share a number of clinical features, such as cognitive impairment and psychomotor retardation, and are highly prevalent in patients with chronic liver disease. Both conditions signify a poor prognosis, carry an increased mortality and are major determinants of reduced health related quality of life. The pathophysiology of hepatic encephalopathy is complex. Whilst cerebral accumulation of ammonia is well-recognised as being central to the development of hepatic encephalopathy, systemic inflammation, which acts in synergy with hyperammonaemia, is emerging as a key driver in its development. The pro-inflammatory state is also widely documented in depression, and peripheral to brain communication occurs resulting in central inflammation, behavioural changes and depressive symptoms. Gut dysbiosis, with a similar reduction in beneficial bacteria, increase in pathogens and decreased bacterial diversity, has been observed in both hepatic encephalopathy and depression, and it may be that the resultant increased bacterial translocation causes their shared inflammatory pathophysiology. Whilst the literature on a positive association between hepatic encephalopathy and depression in cirrhosis remains to be substantiated, there is evolving evidence that treatment with psychobiotics may be of dual benefit, improving cognition and mood in cirrhosis.

Hyperammonemia in Inherited Metabolic Diseases

Ammonia is a neurotoxic compound which is detoxified through liver enzymes from urea cycle. Several inherited or acquired conditions can elevate ammonia concentrations in blood, causing severe damage to the central nervous system due to the toxic effects exerted by ammonia on the astrocytes. Therefore, hyperammonemic patients present potentially life-threatening neuropsychiatric symptoms, whose severity is related with the hyperammonemia magnitude and duration, as well as the brain maturation stage. Inherited metabolic diseases caused by enzymatic defects that compromise directly or indirectly the urea cycle activity are the main cause of hyperammonemia in the neonatal period. These diseases are mainly represented by the congenital defects of urea cycle, classical organic acidurias, and the defects of mitochondrial fatty acids oxidation, with hyperammonemia being more severe and frequent in the first two groups mentioned. An effective and rapid treatment of hyperammonemia is crucial to prevent irreversible neurological damage and it depends on the understanding of the pathophysiology of the diseases, as well as of the available therapeutic approaches. In this review, the mechanisms underlying the hyperammonemia and neurological dysfunction in urea cycle disorders, organic acidurias, and fatty acids oxidation defects, as well as the therapeutic strategies for the ammonia control will be discussed.

Drug-induced-acute liver failure: A critical appraisal of the thioacetamide model for the study of hepatic encephalopathy

Hepatic encephalopathy (HE) following acute and chronic liver failure is defined as a complex of neuropsychiatric abnormalities, such as discrete personal changes, sleep disorder, forgetfulness, confusion, and decreasing the level of consciousness to coma. The use and design of suitable animal models that represent clinical features and pathological changes of HE are valuable to map the molecular mechanisms that result in HE. Among different types of animal models, thioacetamide (TAA) has been used extensively for the induction of acute liver injury and HE. This agent is not directly hepatotoxic but its metabolites induce liver injury through the induction of oxidative stress and produce systemic inflammation similar to that seen in acute HE patients. In this short review article, we shortly review the most important pathological findings in animal models of acute HE following the administration of TAA.

Cognition-tracking-based strategies for diagnosis and treatment of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE), which shows mild cognitive impairment, is a subtle complication of cirrhosis that has been shown to affect daily functioning and quality of life. However, until 2014, relevant guidelines do not give much attention to the diagnosis and treatment of MHE, resulting in patients being ignored and denied the benefits of treatment. In this review, we summarize recent cognition-based research about (1) alteration of nerve cells, including astrocytes, microglial cells and neurons, in mild cognitive impairment in MHE; (2) comparison of methods in detecting cognitive impairment in MHE; and (3) comparison of methods for therapy of cognitive impairment in MHE. We hope to provide information about diagnosis and treatment of cognitive impairment in patients with 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.

Prognosis of Hepatic Encephalopathy

The presence of hepatic encephalopathy is often associated with worse clinical outcomes and increased mortality. Even subclinical hepatic encephalopathy has clinical impacts on daily life and has been linked to increased falls, motor vehicle accidents, and hospitalizations. The presence and degree of hepatic encephalopathy can also affect survival outcomes in cirrhosis, acute liver failure, and liver transplant recipients. Patients may have improved clinical outcomes after treatment of hepatic encephalopathy, but the long-term impact of treatment on prognosis is unclear.

Rifaximin Alleviates Endotoxemia with Decreased Serum Levels of Soluble CD163 and Mannose Receptor and Partial Modification of Gut Microbiota in Cirrhotic Patients

Rifaximin is a poorly absorbable antibiotic against hepatic encephalopathy (HE). This observational study aimed to elucidate the effect of rifaximin on intestinal permeability and gut microbiota in patients with decompensated cirrhosis. Thirty patients with decompensated cirrhosis were assessed by ammonia level, neuropsychological testing, endotoxin activity (EA), and serum proinflammatory cytokines at baseline and after four weeks of rifaximin treatment (1200 mg/day). Intestinal permeability was indicated by serum soluble CD163 (sCD163), mannose receptor (sMR), and zonulin levels. To evaluate the gut microbiome, 16S ribosomal RNA gene sequencing was applied. Rifaximin ameliorated hyperammonemia and cognitive dysfunction, although it did not change the serum proinflammatory cytokine levels. It decreased EA levels as well as serum levels of sCD163 and sMR, but not zonulin, and both decreases in sCD163 and sMR showed positive correlations with EA decrease (ΔsCD163: Correlation coefficient (R) = 0.680, p = 0.023; ΔsMR: R = 0.613, p = 0.014, vs. ΔEA). Gut microbial analysis revealed that the richness and complexity of species were unchanged while the abundance of the Streptococcus genus was reduced after treatment with rifaximin. Collectively, rifaximin alleviated HE and endotoxemia with improved intestinal hyperpermeability in patients with decompensated cirrhosis, and this effect is partially involved in a gut microbial change.

Decreased Mean Kurtosis in the Putamen is a Diagnostic Feature of Minimal Hepatic Encephalopathy in Patients with Cirrhosis

Objective To prevent the development of overt hepatic encephalopathy, the early intervention for minimal hepatic encephalopathy (MHE) based on an accurate diagnosis is essential. This study investigated whether or not magnetic resonance diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI) could detect brain microstructure abnormalities in MHE. The aim was to confirm whether or not brain microstructure abnormalities detected by magnetic resonance (MR) imaging could be used for the diagnosis of MHE. Methods Thirty-two subjects were prospectively examined with a 3-T MR scanner. Tract-based spatial statistics and region of interest analyses of diffusion imaging were performed to compare the mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) values between patients with and without minimal hepatic encephalopathy. The diagnostic performance for the detection of MHE was assessed with a receiver operating characteristic analysis. Results Ten subjects were diagnosed with MHE by neuropsychological testing. After the exclusion of unsuitable subjects, we analyzed 9 subjects with MHE and 14 without MHE. The patients with MHE had a reduced MK in the widespread white matter. We also found significant decreases in the MK in the caudate nucleus, putamen, globus pallidus, and/or thalamus in the subjects with MHE. The MK in the putamen showed the best diagnostic performance for differentiating the subjects with MHE from those without MHE (cut-off value, 0.74; sensitivity, 0.89; specificity, 0.86). Conclusion DKI detects changes in the cerebral white matter and basal ganglia regions of patients with MHE more sensitively than DTI. The MK values in the putamen can be a useful marker for diagnosing MHE from cirrhotic patients without MHE.

Altered Topological Properties of Gray Matter Structural Covariance Networks in Minimal Hepatic Encephalopathy

Background and Aims: Liver cirrhosis commonly induces brain structural impairments that are associated with neurological complications (e.g., minimal hepatic encephalopathy (MHE)), but the topological characteristics of the brain structural network are still less well understood in cirrhotic patients with MHE. This study aimed to conduct the first investigation on the topological alterations of brain structural covariance networks in MHE.

Methods: This study included 22 healthy controls (HCs) and 22 cirrhotic patients with MHE. We calculated the gray matter volume of 90 brain regions using an automated anatomical labeling (AAL) template, followed by construction of gray matter structural covariance networks by thresholding interregional structural correlation matrices as well as graph theoretical analysis.

Results: MHE patients showed abnormal small-world properties of the brain structural covariance network, i.e., decreased clustering coefficient and characteristic path length and lower small-worldness parameters, which indicated a tendency toward more random architecture. In addition, MHE patients lost hubs in the prefrontal and parietal regions, although they had new hubs in the temporal and occipital regions. Compared to HC, MHE patients had decreased regional degree/betweenness involving several regions, primarily the prefrontal and parietal lobes, motor region, insula and thalamus. In addition, the MHE group also showed increased degree/betweenness in the occipital lobe and hippocampus.

Conclusion: These results suggest that MHE leads to altered coordination patterns of gray matter morphology and provide structural evidence supporting the idea that MHE is a neurological complication related to disrupted neural networks.

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.

Predictive models of minimal hepatic encephalopathy for cirrhotic patients based on large-scale brain intrinsic connectivity networks

We aimed to find the most representative connectivity patterns for minimal hepatic encephalopathy (MHE) using large-scale intrinsic connectivity networks (ICNs) and machine learning methods. Resting-state fMRI was administered to 33 cirrhotic patients with MHE and 43 cirrhotic patients without MHE (NMHE). The connectivity maps of 20 ICNs for each participant were obtained by dual regression. A Bayesian machine learning technique, called Graphical Model-based Multivariate Analysis, was applied to determine ICN regions that characterized group differences. The most representative ICNs were evaluated by the performance of three machine learning methods (support vector machines (SVMs), multilayer perceptrons (MLP), and C4.5). The clinical significance of these potential biomarkers was further tested. The temporal lobe network (TLN), and subcortical network (SCN), and sensorimotor network (SMN) were selected as representative ICNs. The distinct functional integration patterns of the representative ICNs were significantly correlated with behavior criteria and Child-Pugh scores. Our findings suggest the representative ICNs based on GAMMA can distinguish MHE from NMHE and provide supplementary information to current MHE diagnostic criteria.

Natural history of covert hepatic encephalopathy: An observational study of 366 cirrhotic patients

AIM

To explore the natural history of covert hepatic encephalopathy (CHE) in absence of medication intervention.

METHODS

Consecutive outpatient cirrhotic patients in a Chinese tertiary care hospital were enrolled and evaluated for CHE diagnosis. They were followed up for a mean of 11.2 ± 1.3 mo. Time to the first cirrhosis-related complications requiring hospitalization, including overt HE (OHE), resolution of CHE and death/transplantation, were compared between CHE and no-CHE patients. Predictors for complication(s) and death/transplantation were also analyzed.

RESULTS

A total of 366 patients (age: 47.2 ± 8.6 years, male: 73.0%) were enrolled. CHE was identified in 131 patients (35.8%). CHE patients had higher rates of death and incidence of complications requiring hospitalization, including OHE, compared to unimpaired patients. Moreover, 17.6% of CHE patients developed OHE, 42.0% suffered persistent CHE, and 19.8% of CHE spontaneously resolved. In CHE patients, serum albumin < 30 g/L (HR = 5.22, P = 0.03) was the sole predictor for developing OHE, and blood creatinine > 133 μmol/L (HR = 4.75, P = 0.036) predicted mortality. Child-Pugh B/C (HR = 0.084, P < 0.001) and OHE history (HR = 0.15, P = 0.014) were predictors of spontaneous resolution of CHE.

CONCLUSION

CHE exacerbates, persists or resolves without medication intervention in clinically stable cirrhosis. Triage of patients based on these predictors will allow for more cost-effect management of CHE.

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.

Probiotics for people with hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy is a disorder of brain function as a result of liver failure or portosystemic shunt or both. Both hepatic encephalopathy (clinically overt) and minimal hepatic encephalopathy (not clinically overt) significantly impair patient's quality of life and daily functioning, and represent a significant burden on healthcare resources. Probiotics are live micro-organisms, which when administered in adequate amounts, may confer a health benefit on the host.

OBJECTIVES

To determine the beneficial and harmful effects of probiotics in any dosage, compared with placebo or no intervention, or with any other treatment for people with any grade of acute or chronic hepatic encephalopathy. This review did not consider the primary prophylaxis of hepatic encephalopathy.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, conference proceedings, reference lists of included trials, and the World Health Organization International Clinical Trials Registry Platform until June 2016.

SELECTION CRITERIA

We included randomised clinical trials that compared probiotics in any dosage with placebo or no intervention, or with any other treatment in people with hepatic encephalopathy.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration. We conducted random-effects model meta-analysis due to obvious heterogeneity of participants and interventions. We defined a P value of 0.05 or less as significant. We expressed dichotomous outcomes as risk ratio (RR) and continuous outcomes as mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 21 trials with 1420 participants, of these, 14 were new trials. Fourteen trials compared a probiotic with placebo or no treatment, and seven trials compared a probiotic with lactulose. The trials used a variety of probiotics; the most commonly used group of probiotic was VSL#3, a proprietary name for a group of eight probiotics. Duration of administration ranged from 10 days to 180 days. Eight trials declared their funding source, of which six were independently funded and two were industry funded. The remaining 13 trials did not disclose their funding source. We classified 19 of the 21 trials at high risk of bias.We found no effect on all-cause mortality when probiotics were compared with placebo or no treatment (7 trials; 404 participants; RR 0.58, 95% CI 0.23 to 1.44; low-quality evidence). No-recovery (as measured by incomplete resolution of symptoms) was lower for participants treated with probiotic (10 trials; 574 participants; RR 0.67, 95% CI 0.56 to 0.79; moderate-quality evidence). Adverse events were lower for participants treated with probiotic than with no intervention when considering the development of overt hepatic encephalopathy (10 trials; 585 participants; RR 0.29, 95% CI 0.16 to 0.51; low-quality evidence), but effects on hospitalisation and change of/or withdrawal from treatment were uncertain (hospitalisation: 3 trials, 163 participants; RR 0.67, 95% CI 0.11 to 4.00; very low-quality evidence; change of/or withdrawal from treatment: 9 trials, 551 participants; RR 0.70, 95% CI 0.46 to 1.07; very low-quality evidence). Probiotics may slightly improve quality of life compared with no intervention (3 trials; 115 participants; results not meta-analysed; low-quality evidence). Plasma ammonia concentration was lower for participants treated with probiotic (10 trials; 705 participants; MD -8.29 μmol/L, 95% CI -13.17 to -3.41; low-quality evidence). There were no reports of septicaemia attributable to probiotic in any trial.When probiotics were compared with lactulose, the effects on all-cause mortality were uncertain (2 trials; 200 participants; RR 5.00, 95% CI 0.25 to 102.00; very low-quality evidence); lack of recovery (7 trials; 430 participants; RR 1.01, 95% CI 0.85 to 1.21; very low-quality evidence); adverse events considering the development of overt hepatic encephalopathy (6 trials; 420 participants; RR 1.17, 95% CI 0.63 to 2.17; very low-quality evidence); hospitalisation (1 trial; 80 participants; RR 0.33, 95% CI 0.04 to 3.07; very low-quality evidence); intolerance leading to discontinuation (3 trials; 220 participants; RR 0.35, 95% CI 0.08 to 1.43; very low-quality evidence); change of/or withdrawal from treatment (7 trials; 490 participants; RR 1.27, 95% CI 0.88 to 1.82; very low-quality evidence); quality of life (results not meta-analysed; 1 trial; 69 participants); and plasma ammonia concentration overall (6 trials; 325 participants; MD -2.93 μmol/L, 95% CI -9.36 to 3.50; very low-quality evidence). There were no reports of septicaemia attributable to probiotic in any trial.

AUTHORS' CONCLUSIONS

The majority of included trials suffered from a high risk of systematic error ('bias') and a high risk of random error ('play of chance'). Accordingly, we consider the evidence to be of low quality. Compared with placebo or no intervention, probiotics probably improve recovery and may lead to improvements in the development of overt hepatic encephalopathy, quality of life, and plasma ammonia concentrations, but probiotics may lead to little or no difference in mortality. Whether probiotics are better than lactulose for hepatic encephalopathy is uncertain because the quality of the available evidence is very low. High-quality randomised clinical trials with standardised outcome collection and data reporting are needed to further clarify the true efficacy of probiotics.

Impact of depressive symptoms and hepatic encephalopathy on health-related quality of life in cirrhotic hepatitis C patients

Depression, common in chronic medical conditions, and hepatic encephalopathy (HE), a reversible neuropsychiatric syndrome due to liver dysfunction, are associated with impaired health-related quality of life (HRQOL) in cirrhosis and hepatitis C (HCV). This study investigated the impact of depression and HE on HRQOL in cirrhotic patients with HCV. A convenience sample of 43 ambulatory patients, with varying degrees of cirrhosis secondary to HCV, was prospectively enrolled in this study. Participants were assessed for any current depressive, fatigue, and daytime sleepiness symptoms and underwent a psychometric evaluation to determine the presence of HE symptoms. Participants reported current HRQOL on general health and liver disease-specific questionnaires. Diagnosis and current health status were confirmed via medical records. The associations between disease severity, depressive symptoms, HE, fatigue, and daytime sleepiness were measured. Predictors of HRQOL in this sample were determined. Depressive symptoms (70 %) and HE (77 %) were highly prevalent in this sample, with 58 % actively experiencing both conditions at the time of study participation. A significant positive association was found between depressive symptoms and HE severity (P = .05). Depressive symptoms were significantly associated with fatigue (P < .001), daytime sleepiness (P < .001), general HRQOL (P < .001), and disease-specific HRQOL (P < .001). HE was significantly associated with fatigue (P = .02), general HRQOL (P < .001), and disease-specific HRQOL (P < .001). Depressive symptoms and HE were significant predictors of reduced HRQOL (P < .001), with depressive symptoms alone accounting for 58.8 % of the variance. Depressive symptoms and HE accounted for 68.0 % of the variance. Findings suggest a possible pathophysiological link between depression and HE in cirrhosis, and potentially a wider-reaching benefit of treating minimal and overt HE than previously appreciated.

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.

Diagnosing and treating hepatic encephalopathy

Hepatic encephalopathy is a complex condition. This article considers the efficacy of the methods used in its diagnosis and management and discusses the impact of minimal hepatic encephalopathy on patients and the ethics of its treatment.

Minimal hepatic encephalopathy and critical flicker frequency are associated with survival of patients with cirrhosis

BACKGROUND & AIMS

Minimal hepatic encephalopathy (MHE) is associated with falls, traffic accidents, and overt HE. However, the association with survival is controversial. We assessed the effects of MHE on the long-term survival of patients with cirrhosis.

METHODS

We performed a prospective study of 117 consecutive patients with cirrhosis seen at a tertiary hospital in Seville, Spain (estimation cohort), followed by a validation study of 114 consecutive patients with cirrhosis seen at 4 hospitals in Spain from January 2004 through December 2007. Patients were examined every 6 months at outpatient clinics through December 2013 (follow-up periods of 5 ± 2.8 y and 4.4 ± 3.9 y for each group, respectively). Cirrhosis was identified by liver biopsy, ultrasound, endoscopic analysis, and biochemical parameters. Liver dysfunction was determined based on model for end-stage liver disease (MELD) and Child-Pugh scores. All patients were administered the critical flicker frequency (CFF) test and psychometric hepatic encephalopathy scores were used to detect MHE. Survival curves were compared using the log-rank test and multivariable analysis was performed using Cox proportional hazards models.

RESULTS

The distributions of Child-Pugh scores were as follows: 66% class A, 31% class B, and 3% class C in the estimation cohort, and 50% class A, 32% class B, and 18% class C in the validation cohort. In the estimation cohort, 24 of 35 patients (68.6%) with a CFF score less than 39 Hz survived for 5 years, whereas 50 of 61 patients (82%) with a CFF score of 39 Hz or higher survived during the follow-up period (log-rank score, 5.07; P = .024). Psychometric hepatic encephalopathy scores did not correlate with survival. In multivariable analysis, older age (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.02-1.12; P = .009), CFF score less than 39 Hz (HR, 4.36; 95% CI, 1.67-11.37; P = .003), and MELD score (HR, 1.40; 95% CI, 1.21-1.63; P = .0001) were associated independently with survival during the follow-up period. In the validation cohort, CFF score less than 39 Hz and MELD score also were associated with patient survival during the follow-up period. MHE had no effect on the survival of patients with MELD scores less than 10 (among patients with CFF scores ≥39 Hz, 94.5% survived for 5 years vs 91.9% of patients with CFF scores <39 Hz; log-rank score, 0.64; P = .423). Fewer patients with MELD scores of 10-15 and MHE survived for 5 years (44.4%; 12 of 27) than those with MELD scores greater than 15 without MHE (61.5%; 8 of 13) (P < .05). Only 2 of 12 patients (16.7%) with MELD scores of 15 or higher and MHE survived for 5 years (log-rank score, 90.56; P = .0001).

CONCLUSIONS

MHE is associated with a reduced 5-year survival rate of patients with cirrhosis. Evaluation of MHE could help predict survival times and outcomes of patients with specific MELD scores. The CFF could help physicians determine prognoses of patients with cirrhosis.

Recent advances in the treatment of hyperammonemia

Ammonia is a neurotoxic agent that is primarily generated in the intestine and detoxified in the liver. Toxic increases in systemic ammonia levels predominantly result from an inherited or acquired impairment in hepatic detoxification and lead to potentially life-threatening neuropsychiatric symptoms. Inborn deficiencies in ammonia detoxification mainly affect the urea cycle, an endogenous metabolic removal system in the liver. Hepatic encephalopathy, on the other hand, is a hyperammonemia-related complication secondary to acquired liver function impairment. A range of therapeutic options is available to target either ammonia generation and absorption or ammonia removal. Therapies for hepatic encephalopathy decrease intestinal ammonia production and uptake. Treatments for urea cycle disorders eliminate ammoniagenic amino acids through metabolic transformation, preventing ammonia generation. Therapeutic approaches removing ammonia activate the urea cycle or the second essential endogenous ammonia detoxification system, glutamine synthesis. Recent advances in treating hyperammonemia include using synergistic combination treatments, broadening the indication of orphan drugs, and developing novel approaches to regenerate functional liver tissue. This manuscript reviews the various pharmacological treatments of hyperammonemia and focuses on biopharmaceutical and drug delivery issues.

Covert Hepatic Encephalopathy: Who Should Be Tested and Treated?

Covert hepatic encephalopathy is a common problem in cirrhosis, affecting up to 80% of patients. It is defined as test-dependent brain dysfunction with clinical consequences in the setting of cirrhosis in patients who are not disoriented. Because it is not apparent clinically, and diagnostic testing has not been standardized, the issue has often been ignored in clinical practice. Yet, the clinical consequences are notable, including impaired quality of life, diminished work productivity, and poor driving skills.

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.

Using saccades to diagnose covert hepatic encephalopathy

Covert Hepatic Encephalopathy (CHE), previously known as Minimal Hepatic Encephalopathy, is a subtle cognitive defect found in 30-70 % of cirrhosis patients. It has been linked to poor quality of life, impaired fitness to drive, and increased mortality: treatment is possible. Despite its clinical significance, diagnosis relies on psychometric tests that have proved unsuitable for use in a clinical setting. We investigated whether measurement of saccadic latency distributions might be a viable alternative. We collected data on 35 cirrhosis patients at Addenbrooke's Hospital, Cambridge, with no evidence of clinically overt encephalopathy, and 36 age-matched healthy controls. Performance on standard psychometric tests was evaluated to determine those patients with CHE as defined by the World Congress of Gastroenterology. We then compared visually-evoked saccades between those with CHE and those without, as well as reviewing blood test results and correlating saccadic latencies with biochemical parameters and prognostic scores. Cirrhosis patients have significantly longer median saccadic latencies than healthy controls. Those with CHE had significantly prolonged saccadic latencies when compared with those without CHE. Analysis of a cirrhosis patient's saccades can diagnose CHE with a sensitivity of 75 % and a specificity of 75 %. We concluded that analysis of a cirrhosis patient's saccadic latency distributions is a fast and objective measure that can be used as a diagnostic tool for CHE. This improved early diagnosis could direct avoidance of high-risk activities such as driving, and better inform treatment strategies.

Minimal hepatic encephalopathy impairs quality of life

Minimal hepatic encephalopathy (MHE) is the mildest form of the spectrum of neurocognitive impairment in cirrhosis. It is a frequent occurrence in patients of cirrhosis and is detectable only by specialized neurocognitive testing. MHE is a clinically significant disorder which impairs daily functioning, driving performance, work capability and learning ability. It also predisposes to the development of overt hepatic encephalopathy, increased falls and increased mortality. This results in impaired quality of life for the patient as well as significant social and economic burden for health providers and care givers. Early detection and treatment of MHE with ammonia lowering therapy can reverse MHE and improve quality of life.

Default mode network functional connectivity: a promising biomarker for diagnosing minimal hepatic encephalopathy: CONSORT-compliant article

To investigate the contribution of brain default mode network (DMN) in the early diagnosis of the minimal hepatic encephalopathy (MHE), the mildest form of HE from cirrhotic patients by using resting-state functional magnetic resonance imaging (rs-fMRI). This study was approved by the local ethical committee, and a written informed consent was obtained from each participant. A total of 103 cirrhotic patients (34 MHE, 69 non-HE) and 103 matched healthy controls underwent rs-fMRI scanning. The DMN correlation map was acquired by using unbiased seed-based functional connectivity analysis and compared among MHE patients, non-HE patients, and healthy controls with analysis of variance tests. Pearson correlation analysis was performed between the abnormal DMN connectivity and neuropsychological performances. Receiver operator characteristic (ROC) analysis was used to evaluate the contribution of DMN connectivity strength in the differential diagnosis between MHE and non-HE. Compared with the healthy controls, MHE and non-HE patients showed decreased DMN connectivity in medial prefrontal cortex (MPFC), left superior frontal gyrus (SFG), left temporal lobe, and bilateral middle temporal gyri (MTG). The MHE patients showed even more decreased connectivity in MPFC, left SFG, and right MTG when compared with non-HE patients. Pearson correlation analyses revealed that the decreased connectivity strength of some DMN regions correlated with patients' neuropsychological tests scores. Connectivity strength of the MPFC, right MTG, and left SFG could differentiate MHE from non-HE, of which the MPFC had the highest effectiveness (sensitivity = 81.5%, specificity = 70.4%). Cirrhotic patients had gradually reduced DMN functional connectivity from non-HE patients to MHE patients. DMN function, especially the MPFC, might be a useful imaging marker for differentiating MHE from cirrhotic patients.

Minimal hepatic encephalopathy in children with liver cirrhosis: diffusion-weighted MR imaging and proton MR spectroscopy of the brain

INTRODUCTION

The aim of this work was to detect minimal hepatic encephalopathy (minHE) in children with diffusion-weighted MR imaging (DWI) and proton magnetic resonance spectroscopy (1H-MRS) of the brain.

METHODS

Prospective study conducted upon 30 consecutive children (age range 6-16 years, 21 boys and 9 girls) with liver cirrhosis and 15 age- and sex-matched healthy control children. Patients with minHE (n = 17) and with no minHE (n = 13) groups and control group underwent DWI, 1H-MRS, and neuropsychological tests (NPTs). The glutamate or glutamine (Glx), myoinositol (mI), choline (Cho), and creatine (Cr) at the right ganglionic region were determined at 1H-MRS. The apparent diffusion coefficient (ADC) value and metabolic ratios of Glx/Cr, mI/Cr, and Cho/Cr were calculated.

RESULTS

There was elevated ADC value and Glx/Cr and decreased mI/CI and Ch/Cr in patients with minHE compared to no minHE and control group. There was significant difference between minHE, no minHE, and control group in the ADC value (P = 0.001 for all groups), GLx/Cr (P = 0.001 for all groups), mI/Cr (P = 0.004, 0.001, and 0.001, respectively), Ch/Cr (P = 0.001 for all groups), and full-scale IQ of NPT (P = 0.001, 0.001, and 0.143, respectively). The NPT of minHE had negative correlation with ADC value (r = -0.872, P = 0.001) and GLx/Cr (r = -0.812, P = 0.001) and positive correlation with mI/Cr (r = 0.732, P = 0.001).

CONCLUSION

DWI and 1H-MRS are imaging modalities that can detect minHE in children with liver cirrhosis and correlate well with parameters of NPT.

Treatment options for covert hepatic encephalopathy

OPINION STATEMENT

The main issue with treating covert hepatic encephalopathy (HE) is to establish whether it is cost effective to reverse the neuropsychiatric abnormalities that define this mild form of HE. Until fairly recently, covert HE was rarely diagnosed, but advances in computerized psychometric testing have greatly simplified its detection. The many consequences of covert HE are now being identified, and most have been shown to be reversible with standard HE treatment. Perhaps the most enticing possibility will be the potential that standard HE therapies will postpone the onset of overt HE. This will require further evaluation with large placebo-controlled randomized trials.

Increased brain lactate is central to the development of brain edema in rats with chronic liver disease

BACKGROUND & AIMS

The pathogenesis of brain edema in patients with chronic liver disease (CLD) and minimal hepatic encephalopathy (HE) remains undefined. This study evaluated the role of brain lactate, glutamine and organic osmolytes, including myo-inositol and taurine, in the development of brain edema in a rat model of cirrhosis.

METHODS

Six-week bile-duct ligated (BDL) rats were injected with (13)C-glucose and de novo synthesis of lactate, and glutamine in the brain was quantified using (13)C nuclear magnetic resonance spectroscopy (NMR). Total brain lactate, glutamine, and osmolytes were measured using (1)H NMR or high performance liquid chromatography. To further define the interplay between lactate, glutamine and brain edema, BDL rats were treated with AST-120 (engineered activated carbon microspheres) and dichloroacetate (DCA: lactate synthesis inhibitor).

RESULTS

Significant increases in de novo synthesis of lactate (1.6-fold, p<0.001) and glutamine (2.2-fold, p<0.01) were demonstrated in the brains of BDL rats vs. SHAM-operated controls. Moreover, a decrease in cerebral myo-inositol (p<0.001), with no change in taurine, was found in the presence of brain edema in BDL rats vs. controls. BDL rats treated with either AST-120 or DCA showed attenuation in brain edema and brain lactate. These two treatments did not lead to similar reductions in brain glutamine.

CONCLUSIONS

Increased brain lactate, and not glutamine, is a primary player in the pathogenesis of brain edema in CLD. In addition, alterations in the osmoregulatory response may also be contributing factors. Our results suggest that inhibiting lactate synthesis is a new potential target for the treatment of HE.

Health related quality of life in patients with biliary atresia surviving with their native liver

OBJECTIVES

To quantify health related quality of life (HRQOL) of patients with biliary atresia with their native livers and compare them with healthy children and patients with biliary atresia post-liver transplant (LT) and to examine the relationship between HRQOL and medical variables.

STUDY DESIGN

A cross-sectional HRQOL study of patients with biliary atresia with their native livers (ages 2-25 years) was conducted and compared with healthy and post-LT biliary atresia samples using Pediatric Quality of Life Inventory 4.0 child self and parent proxy reports, a validated measure of physical/psychosocial functioning.

RESULTS

221 patients with biliary atresia with native livers (54% female, 67% white) were studied. Patient self and parent proxy reports showed significantly poorer HRQOL than healthy children across all domains (P < .001), particularly in emotional and psychosocial functioning. Child self and parent proxy HRQOL scores from patients with biliary atresia with their native livers and post-LT biliary atresia were similar across all domains (P = not significant). Child self and parent proxy reports showed moderate agreement across all scales, except social functioning (poor to fair agreement). On multivariate regression analysis, black race and elevated total bilirubin were associated with lower Total and Psychosocial HRQOL summary scores.

CONCLUSIONS

HRQOL in patients with biliary atresia with their native livers is significantly poorer than healthy children and similar to children with post-LT biliary atresia. These findings identify significant opportunities to optimize the overall health of patients with biliary atresia.

Low fat intake is associated with pathological manifestations and poor recovery in patients with hepatocellular carcinoma

BACKGROUND

This study aimed to clarify whether dietary deviation is associated with pathological manifestations in hepatocellular carcinoma (HCC) patients.

METHODS

Dietary intake was estimated in 35 HCC cases before and after hospitalization by referencing digital camera images of each meal. Pathological conditions were evaluated in nitrogen balance, non-protein respiratory quotient (npRQ), neuropsychiatric testing and recovery speed from HCC treatment.

RESULTS

On admission, nitrogen balance and npRQ were negative and less than 0.85, respectively. Five patients were judged to have suffered from minimal hepatic encephalopathy that tended to be associated with a lowered value of npRQ (p = 0.082). The energy from fat intake showed a tendency of positive correlation with npRQ (p = 0.11), and the patients with minimal hepatic encephalopathy took significantly fewer energy from fat (p = 0.024). The energy difference from fat between diets at home versus those in the hospital showed a significant positive correlation with npRQ change after admission (p = 0.014). The recovery speed from invasive treatments for HCC showed a significant negative correlation with npRQ alteration after admission (p = 0.0002, r = -0.73).

CONCLUSIONS

These results suggest the lower fat intake leads to deterioration of energy state in HCC patients, which associates with poor recovery from invasive treatments and various pathological manifestations.

Lipid profile is associated with the incidence of cognitive dysfunction in viral cirrhotic patients: A data-mining analysis

AIM

  Cognitive dysfunction (CD) is frequently observed in cirrhotic patients. However, the biochemical profiles associated with CD remain unclear. We investigated the biochemical profiles associated with the incidence of CD in cirrhotic patients by using multivariate analyses, including a decision-tree algorithm.

METHODS

  In this study, 27 viral cirrhotic patients were enrolled. All subjects underwent neuropsychiatric tests; two or more abnormal results were defined as CD. A logistic regression model was used for multivariate stepwise analysis. A decision-tree algorithm was constructed, and the categorical differences based on the decision-tree model were analyzed by χ(2) -tests.

RESULTS

  Multivariate stepwise analysis showed the levels of total bilirubin, triglycerides and free fatty acids (FFA) as independent bioparameters associated with the incidence of CD in cirrhotic patients. The decision-tree algorithm showed that among patients with FFA of 514 mEq/L or more, 77.8% had CD. Meanwhile, among patients with FFA of less than 514 mEq/L and triglycerides of 106 mg/dL or more, 20.0% had CD. The sensitivity, specificity and accuracy for the incidence of CD using the lipid profile (FFA >514 mEq/L or triglycerides <106 mg/dL) were 85.7% (12/14), 61.5% (8/13) and 74.1% (20/27), respectively.

CONCLUSION

  The levels of total bilirubin, FFA and triglycerides are independently associated with the incidence of CD in cirrhotic patients. In addition, a decision-tree algorithm revealed that FFA of more than 514 mEq/L or triglycerides of less than 106 mg/dL is a profile associated with the incidence of CD. Thus, this lipid profile could be a possible screening bioparameter for CD in cirrhotic patients.

Does magnetic resonance spectroscopy identify patients with minimal hepatic encephalopathy?

BACKGROUND AND PURPOSE

The results of a few studies suggest that magnetic resonance spectroscopy of the brain could allow detection of minimal hepatic encephalopathy. The goal of this study was to assess the ability of magnetic resonance spectroscopy to differentiate between cirrhotic patients with and without minimal hepatic encephalopathy.

MATERIAL AND METHODS

Localized magnetic resonance spectroscopy was performed in the basal ganglia, occipital gray matter and frontal white matter in 46 patients with liver cirrhosis without overt encephalopathy and in 45 controls. Neurological and neuropsychological examination was performed in each participant.

RESULTS

The patients with liver cirrhosis had a decreased ratio of myoinositol to creatine in occipital gray matter and frontal white matter (mean: 0.17 ± 0.05 vs. 0.20 ± 0.04, p = 0.01 and 0.15 ± 0.05 vs. 0.19 ± 0.04, p < 0.01, respectively) and a decreased ratio of choline to creatine in occipital gray matter (mean: 0.32 ± 0.07 vs. 0.36 ± 0.08, p = 0.03). Minimal hepatic encephalopathy was diagnosed in 7 patients. Metabolite ratios did not differ significantly between patients with and without minimal hepatic encephalopathy. Metabolite ratios did not differ significantly between patients with Child-Pugh A and those with Child-Pugh B.

CONCLUSIONS

Magnetic resonance spectroscopy does not allow accurate diagnosis of minimal hepatic encephalopathy. A similar profile of metabolites in the brain is observed in cirrhotic patients without cognitive impairment.

Covert hepatic encephalopathy: not as minimal as you might think

Hepatic encephalopathy (HE) is a serious neuropsychiatric and neurocognitive complication of acute and chronic liver disease. Symptoms are often overt (confusion, disorientation, ataxia, or coma) but can also be subtle (difficulty with cognitive abilities such as executive decision-making and psychomotor speed). There is consensus that HE is characterized as a spectrum of neuropsychiatric symptoms in the absence of brain disease, ranging from overt HE (OHE) to minimal HE (MHE). The West Haven Criteria are most often used to grade HE, with scores ranging from 0-4 (4 being coma). However, it is a challenge to diagnose patients with MHE or grade 1 HE; it might be practical to combine these entities and name them covert HE for clinical use. The severity of HE is associated with the stage of liver disease. Although the pathologic mechanisms of HE are not well understood, they are believed to involve increased levels of ammonia and inflammation, which lead to low-grade cerebral edema. A diagnosis of MHE requires dedicated psychometric tests and neurophysiological techniques rather than a simple clinical assessment. Although these tests can be difficult to perform in practice, they are cost effective and important; the disorder affects patients' quality of life, socioeconomic status, and driving ability and increases their risk for falls and the development of OHE. Patients with MHE are first managed by excluding other causes of neurocognitive dysfunction. Therapy with gut-specific agents might be effective. We review management strategies and important areas of research for MHE and covert HE.

Ammonia-lowering strategies for the treatment of hepatic encephalopathy

Hyperammonemia leads to neurotoxic levels of brain ammonia and is a major factor involved in the pathogenesis of hepatic encephalopathy (HE). Ammonia-lowering treatments primarily involve two strategies: inhibiting ammonia production and/or increasing ammonia removal. Targeting the gut has been the primary focus for many years, with the goal of inhibiting the generation of ammonia. However, in the context of liver failure, extrahepatic organs containing ammonia metabolic pathways have become new potential ammonia-lowering targets. Skeletal muscle has the capacity to remove ammonia by producing glutamine through the enzyme glutamine synthetase (amidation of glutamate) and, given its large mass, has the potential to be an important ammonia-removing organ. On the other hand, glutamine can be deaminated to glutamate by phosphate-activated glutaminase, thus releasing ammonia (ammonia rebound). Therefore, new treatment strategies are being focused on stimulating the removal of both ammonia and glutamine.

Advances in diagnosis and treatment of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE), also known as subclinical hepatic encephalopathy (SHE), is a common complex and potentially reversible neuropsychiatric syndrome secondary to chronic liver disease or cirrhosis. Although a clear pathogenesis is yet to be determined, elevated ammonia in serum and the central nervous system is the mainstay for pathogenesis and treatment of MHE. Patients with MHE, regardless of its cause, show a number of quantifiable neuropsychological defects, yet have a normal mental and neurological status on global clinical examination. Although ammonia is the main toxic substance involved in the pathogenesis of hepatic encephalopathy, other mechanisms, such as modifications of the blood-brain barrier, disruptions in neurotransmission and abnormalities in GABAergic and benzodiazepine pathways, may also play a role. Current treatments are based on reducing intestinal ammonia load by agents such as antibiotics, disaccharides and probiotics whose efficacy is yet to be clearly established. This paper summarizes the latest advances in the diagnosis and treatment of MHE.

Hepatic encephalopathy

Hepatic encephalopathy (HE) represents a continuum of transient and reversible neurologic and psychiatric dysfunction. It is a reversible state of impaired cognitive function or altered consciousness in patients with liver disease or portosystemic shunting. Over the last several years, high-quality studies have been conducted on various pharmacologic therapies for HE; as more data emerge, it is hoped that HE will become a more easily treated complication of decompensated liver disease. In the interim, it is important that physicians continue to screen for minimal HE and treat patients early in addition to continuing to provide current treatments of overt HE.

Focal cortical damage parallels cognitive impairment in minimal hepatic encephalopathy

Little attention has been paid to cortical integrity in patients with minimal hepatic encephalopathy (MHE), although cognitive functions affected in early stages of liver disease are mainly allocated in different neocortical structures. Here we used cortical surface-based analysis techniques to investigate if patterns of cortical thinning accompany the mildest form of HE. To aim this goal, cortical thickness obtained from high-resolution 3T magnetic resonance imaging (MRI) was measured in patients with no MHE (NMHE), MHE, and healthy controls. Further correlation analyses were performed to examine whether scores in the critical flicker frequency (CFF) test, and blood ammonia levels accounted for the loss of cortical integrity in different stages of liver disease. Finally, we assessed group differences in volume of different subcortical regions and their potential relationships with CFF scores/blood ammonia levels. Results showed a focal thinning of the superior temporal cortex and precuneus in MHE patients when compared with NMHE and controls. Relationships between blood ammonia levels and cortical thickness of the calcarine sulcus accounted for impaired visual judgment in patients with MHE when compared to NMHE. Regression analyses between cortical thickness and CFF predicted differences between controls and the two groups of HE patients, but failed to discriminate between patients with NMHE and MHE. Taking together, these findings provide the first report of cortical thinning in MHE patients, and they yield novel insights into the neurobiological basis of cognitive impairment associated with early stages of liver diseases.

Hepatic encephalopathy and health-related quality of life

The impact of overt hepatic encephalopathy on health-related quality of life is well defined, but it remains to be demonstrated how much the presence of minimal hepatic encephalopathy (MHE) might impair patients' perceived health status. MHE reduces cognitive abilities, with specific impairment in manual abilities, which can lead to a depressed mood that impairs perceived health status. Therefore, all subjects with cirrhosis should be systematically screened for MHE by validated tools. Early detection and treatment is mandatory to improve the quality of life of patients with advanced cirrhosis, their social isolation, and their daily lives.

Probiotics for patients with hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy is a disorder of brain function as a result of liver failure and/or portosystemic shunt. Both hepatic encephalopathy (clinically overt) and minimal hepatic encephalopathy (not clinically overt) significantly impair patient's quality of life and daily functioning and represent a significant burden on health care resources. Probiotics are live microorganisms, which when administered in adequate amounts may confer a health benefit on the host.

OBJECTIVES

To quantify the beneficial and harmful effects of any probiotic in any dosage, compared with placebo or no intervention, or with any other treatment for patients with any grade of acute or chronic hepatic encephalopathy as assessed from randomised trials.

SEARCH METHODS

We searched the The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, conference proceedings, reference lists of included trials and the WHO international clinical trials registry until April 2011 registry platform to identify new and ongoing trials.

SELECTION CRITERIA

We included randomised trials that compared probiotics in any dosage with placebo or no intervention, or with any other treatment in patients with hepatic encephalopathy.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed the risk of bias of the included trials and extracted data on relevant outcomes, with differences resolved by consensus. We conducted random-effects model meta-analysis due to obvious heterogeneity of patients and interventions. A P value of 0.05 or less was defined as significant. Dichotomous outcomes are expressed as risk ratio (RR) and continuous outcomes as mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included seven trials of which 550 participants were randomised. Four of the seven trials compared a probiotic with placebo or no treatment in 245 participants, another trial compared a probiotic with lactulose in 40 participants , and the remaining two trials compared a probiotic with both placebo and lactulose in 265 participants. Each trial used different types of probiotics. Duration of administration of the experimental intervention varied from 10 days to 180 days. Two trials were industry funded, and five were unclear about origin of funding. All trials had high risk of bias. When probiotics were compared with no treatment, there was no significant difference in all-cause mortality (2 trials, 105 participants; 1/57 (2%) versus 1/48 (2%): RR 0.72; 95% CI 0.08 to 6.60), lack of recovery (4 trials, 206 participants; 54/107 (50%) versus 68/99 (69%): RR 0.72; 95% CI 0.49 to 1.05), adverse events (3 trials, 145 participants; 2/77 (3%) versus 6/68 (9%): RR 0.34; 95% CI 0.08 to 1.42), quality of life (1 trial, 20 participants contributed to the physical quality of life measurement, 20 participants contributed to the mental quality of life: MD Physical 0.00; 95% CI -5.47 to 5.47; MD Mental 4.00; 95% CI -1.82 to 9.82), or change of/or withdrawal from treatment (3 trials, 175 participants; 11/92 (12%) versus 7/83 (8%): RR 1.28; 95% CI 0.52 to 3.19). No trial reported sepsis or duration of hospital stay as an outcome. Plasma ammonia concentration was significantly lower for participants treated with probiotic at one month (3 trials, 226 participants: MD -2.99 μmol/L; 95% CI -5.70 to -0.29) but not at two months (3 trials, 181 participants: MD -1.82 μmol/L; 95% CI -14.04 to 10.41). Plasma ammonia decreased the most in the participants treated with probiotic at three months (1 trial, 73 participants: MD -6.79 μmol/L; 95% CI -10.39 to -3.19). When probiotics were compared with lactulose no trial reported all-cause mortality, quality of life, duration of hospital stay, or septicaemia. There were no significant differences in lack of recovery (3 trials, 173 participants; 47/87 (54%) versus 44/86 (51%): RR 1.05; 95% CI 0.75 to 1.47), adverse events (2 trials, 111 participants; 3/56 (5%) versus 6/55 (11%): RR 0.57; 95% CI 0.06 to 5.74), change of/or withdrawal from treatment at one month (3 trials, 190 participants; 8/95 (8%) versus 7/95 (7%): RR 1.10; 95% CI 0.40 to 3.03), plasma ammonia concentration (2 trials, 93 participants: MD -6.61 μmol/L; 95% CI -30.05 to 16.84), or change in plasma ammonia concentration (1 trial, 77 participants: MD 1.16 μmol/L; 95% CI -1.96 to 4.28).

AUTHORS' CONCLUSIONS

The trials we located suffered from a high risk of systematic errors ('bias') and high risk of random errors ('play of chance'). While probiotics appear to reduce plasma ammonia concentration when compared with placebo or no intervention, we are unable to conclude that probiotics are efficacious in altering clinically relevant outcomes. Demonstration of unequivocal efficacy is needed before probiotics can be endorsed as effective therapy for hepatic encephalopathy. Further randomised clinical trials are needed.

Multi-dimensional MR spectroscopy: towards a better understanding of hepatic encephalopathy

Hepatic encephalopathy (HE) is normally diagnosed by neuropsychological (NP) tests. The goals of this study were to quantify cerebral metabolites, separate glutamate (Glu) from glutamine (Gln) in patients with minimal hepatic encephalopathy (MHE) as well as healthy subjects using the prior-knowledge fitting (ProFit) algorithm on data acquired by two-dimensional (2D) localized correlated spectroscopy (L-COSY) on two different MR scanners, and to correlate the metabolite changes with neuropsychological (NP) tests. We studied 14 MHE patients and 18 healthy controls using a GE 1.5 T Signa MR scanner. Another group of 16 MHE patients and 18 healthy controls were studied using a Siemens 1.5 T Avanto MR scanner. The following parameters were used for L-COSY: TR/TE = 2 s/30 ms, 3 × 3 × 3 cm(3) voxel size, 96 Δt(1) increments with 8 averages per Δt(1). Using the ProFit algorithm, we were able to differentiate Gln from Glu on the GE 1.5 T data in the medial frontal white/gray matter. The ratios of myo-inositol (mI), Glu, total choline, scyllo-inositol (sI), phosphoethanolamine (PE), and total N-acetyl aspartate (NAA) showed statistically significant decline in HE patients compared to healthy controls, while the ratio of Gln was significantly increased. Similar trend was seen in the ProFit quantified Siemens 1.5 T data in the frontal and occipito-parietal white/gray regions. Among the NP domain scores, motor function, cognitive speed, executive function and the global scores showed significant differences. Excellent correlations between various NP domains and metabolite ratios were also observed. ProFit based cerebral metabolite quantitation enhances the understanding and basis of the current hypothesis of MHE.

Rifaximin for the treatment of hepatic encephalopathy

Hepatic encephalopathy (HE) is a complication of cirrhosis, the severity of which can range from subtle, neurocognitive dysfunction (minimal HE) to more apparent and severe cognitive and motor manifestations with increasing grades of the condition (overt HE). Current treatment options are targeted at reducing the levels of ammonia and other gut-derived toxins, the purported culprits behind the pathogenesis of HE. One of these therapeutic options, the nonsystemic antibiotic rifaximin, is efficacious for the treatment of minimal and overt HE. However, HE may be a cyclic condition in which patients with overt HE enter remission following treatment and then relapse. Thus, safe, effective and well-tolerated treatments are needed to maintain HE remission. Rifaximin maintained HE remission more effectively than placebo in a large, randomized controlled trial. Rifaximin is safe and well-tolerated for the treatment of minimal and overt HE and for the maintenance of HE remission.

Prevalence of abnormal psychometric tests and critical flicker frequency after clinical recovery of overt hepatic encephalopathy

BACKGROUND

Abnormal psychometric tests are common in cirrhotic patients without overt encephalopathy. It may seriously impair the patient's daily functioning and quality of life. Prevalence of abnormal psychometric tests after the clinical recovery of overt encephalopathy has not been studied.

MATERIALS AND METHODS

Consecutive 80 patients (age, 44.5+/-9.8 yr; M: F 66:14) with hepatic encephalopathy (HE) who recovered and met inclusion criteria were evaluated for abnormal psychometric tests ( > 2 SD) and critical flicker frequency (CFF < 38 Hz). All patients underwent number connection tests-A and B, figure connection tests -A and B (if illiterate), digit symbol test, object assembly test, CFF and arterial ammonia after one month of clinical recovery of HE.

RESULTS

Prevalence of abnormal psychometric tests (> 2SD) was seen in 58 (72.5%) patients. [33 (66%) of 50 patients on lactulose and 25 (83%) of 30 patients not on lactulose, P = 0.12]. Arterial ammonia was significantly higher in patients with abnormal psychometric tests compared to patients without it (86.3+/-22.2 vs 50.4+/-11.5 mmol/l, P = 0.01). CFF was < 38 Hz in 50 patients (62.5%). Patients with > or =2 abnormal psychometric tests had CFF significantly lower than with normal psychometric tests (35.6+/-2.3 vs 40.7+/-2.4 Hz, P = 0.001). CFF sensitivity and specificity in diagnosing > or =2 abnormal psychometric tests was 82 and 83% respectively. CFF was significantly correlated with psychometric tests [NCT-A (-0.672, P = 0.001) and B (-0.743, P = 0.001), digit symbol test (-0.533, P = 0.001), object assembly test (-0.659, P =0.001) and arterial ammonia level (-0.385, P = 0.02)].

CONCLUSION

About 73% of patients who recovered from HE had abnormal psychometric tests ( > 2SD). CFF is a simple reliable tool to find out the presence of abnormal tests.

Cognitive function does not worsen during long-term low-dose peginterferon therapy in patients with chronic hepatitis C

OBJECTIVES

Neuropsychiatric toxicity is a common dose-limiting side effect of interferon therapy. The primary aim of this study was to determine whether patients receiving long-term low-dose peginterferon therapy had a higher incidence of cognitive side effects compared with untreated patients enrolled in the Hepatitis C Antiviral Long-Term treatment against Cirrhosis (HALT-C) Trial.

METHODS

A total of 129 patients with chronic hepatitis C and advanced fibrosis completed a battery of 10 neuropsychological tests and the Beck Depression Inventory at pretreatment baseline and at months 12, 24, 36, and 48 while receiving long-term peginterferonalpha2a (90 microg/week) or no therapy during the randomized phase of the HALT-C Trial. Cognitive impairment was defined as a global deficit score (GDS) > or = 1.0.

RESULTS

The mean age was 51.2 years, 67% were male, and 42% had cirrhosis. After accounting for baseline GDS scores, the mean GDS scores did not significantly change over time (P=0.46) nor with treatment group (P=0.49). Cognitive function was also not influenced by medication adherence in the 66 patients receiving maintenance peginterferon (P=0.14) after controlling for baseline GDS scores and time. Beck Depression scores did not significantly increase over time (P=0.60), nor did they vary by treatment group (P=0.74). Although 32% of patients experienced objective worsening of their liver disease during follow-up, the frequency and severity of cognitive impairment did not differ in those with and without disease progression (P=0.71).

CONCLUSIONS

Measures of cognitive function were neither influenced by low-dose peginterferon treatment nor with objective evidence of liver disease progression in patients with advanced chronic hepatitis C prospectively followed up for 3.5 years.