Rifaximin therapy and hepatic encephalopathy: Pros and cons

Management of hepatic encephalopathy following transjugular intrahepatic portosystemic shunts: Current strategies and future directions

Transjugular intrahepatic portosystemic shunts (TIPSs) are generally used for the management of complications of portal hypertension in patients with decompensated cirrhosis. However, hepatic encephalopathy (HE), which impairs neuropsychiatric function and motor control, remains the primary adverse effect of TIPS, limiting its utility. Prompt prevention and treatment of post-TIPS HE are critical, as they are strongly associated with readmission rates and poor quality of life. This review focuses on the main pathophysiological mechanisms underlying post-TIPS HE, explores advanced biomarkers and predictive tools, and discusses current management strategies and future directions to prevent or reverse HE following TIPS. These strategies include preoperative patient assessment, individualized shunt diameter optimization, spontaneous portosystemic shunt embolization during the TIPS procedure, postoperative preventive and therapeutic measures such as nutrition management, medical therapy, fecal microbiota transplantation, and stent reduction.

Flaxseed Oil (Linum usitatissimum) Prevents Cognitive and Motor Damage in Rats with Hyperammonemia

Hyperammonemia is characterized by the excessive accumulation of ammonia in the body as a result of the loss of liver detoxification, leading to the development of hepatic encephalopathy (HE). These metabolic alterations carry cognitive and motor deficits and cause neuronal damage, with no effective treatment at present. In this study, we aimed to evaluate the effect of two subacute oral administrations of flaxseed oil (0.26 and 0.52 mL/kg) on short- and long-term memory, visuospatial memory, locomotor activity, motor coordination, and the neuronal morphology of the prefrontal cortex (PFC) via tests on Wistar rats with hyperammonemia. The goal was to identify its role in the regulation of cerebral edema, without liver damage causing cerebral failure. In contrast with an ammonium-rich diet, flaxseed oil and normal foods did not cause cognitive impairment or motor alterations, as evidenced in the short-term and visuospatial memory tests. Furthermore, the flaxseed oil treatment maintained a regular neuronal morphology of the prefrontal cortex, which represents a neuroprotective effect. We conclude that the oral administration of flaxseed oil prevents cognitive and motor impairments as well as neuronal alterations in rats with hyperammonemia, which supports the potential use of this oil to ameliorate the changes that occur in hepatic encephalopathy.

The emerging role of the gut mycobiome in liver diseases

In recent years, it has become clear that gut microbiota plays a major role in the human body, both in health and disease. Because of that, the gut microbiome and its impact on human well-being are getting wider and wider attention. Studies focused on the liver are not an exception. However, the majority of the analyses are concentrated on the bacterial part of the gut microbiota, while the fungi living in the human intestines are often omitted or underappreciated. This review is focused on the gut mycobiome as an important factor that should be taken into consideration regarding liver homeostasis and its perturbations. We have collected the findings in this field and we discuss their importance. We aim to emphasize the fungal compositional changes related to liver diseases and, by that, provide novel insights into the directions of liver research and gut microbiota as a therapeutic target for liver diseases.

Novel Agents in the Management of Hepatic Encephalopathy: A Review

Hepatic encephalopathy is an often devastating complication of chronic liver disease, associated with high mortality and increased burden on patients and healthcare systems. Current agents (such as nonabsorbable disaccharides and oral antibiotics) are often only partially effective and associated with unpleasant side effects. With our improved understanding of the pathophysiology of hepatic encephalopathy, multiple treatment modalities have emerged with promising results when used alone or as an adjunct to standard medications. The mechanisms of these agents vary greatly, and include the manipulation of gut microbial composition, reduction of oxidative stress, inhibition of inflammatory mediators, protection of endothelial integrity, modulation of neurotransmitter release and function, and other novel methods to reduce blood ammonia and neurotoxins. Despite their promising results, the studies assessing these treatment modalities are often limited by study design, sample size, outcome assessment heterogeneity, and paucity of data regarding their safety profiles. In this article, we discuss these novel agents in depth and provide the best evidence supporting their use, along with a critical look at their limitations and future directions.

Nitazoxanide versus rifaximin in preventing the recurrence of hepatic encephalopathy: A randomized double-blind controlled trial

BACKGROUND/PURPOSE

Hepatic encephalopathy (HE) is a neuropsychiatric complication of liver cirrhosis. HE is associated with poor survival and detrimental effects on quality of life (QOL). The drawbacks of the long-term use of rifaximin in HE necessitates searching for alternative therapies. In this context, our study aimed at evaluating the safety and efficacy of nitazoxanide (NTZ) as compared to rifaximin (RFX) in preventing the recurrence of HE and assessing its impact on QOL.

PATIENTS AND METHODS

This prospective, randomized, double-blind controlled study included 60 patients who were randomly assigned to receive either rifaximin 550 mg twice daily (group 1; n = 30) or nitazoxanide 500 mg twice daily (group 2; n = 30) for 24 weeks. During the study period, the patients' neurological symptoms, mental status, and performance were monitored. The serum levels of HE triggers (ammonia, TNF-α, and octopamine) were assessed. The patients' health-related quality of life was also evaluated.

RESULTS

Six months after treatment, patients on NTZ therapy showed a statistically significant improvement in CHESS score and mental status. NTZ provided 136 days of remission vs 67 days of remission for patients on RFX (P1  = .0001) and significant reduction in Child score (P1  = .018). Additionally, NTZ showed a statistically significant decrease in serum ammonia, TNF-α, and octopamine levels as compared to rifaximin. Regarding QOL, NTZ group showed an improvement in total Chronic Liver Disease Questionnaire (CLDQ) score. Both groups experienced minor controllable side effects.

CONCLUSION

Nitazoxanide may represent a suitable and safe alternative therapy to rifaximin in preventing the recurrence of hepatic encephalopathy.

Role of circadian rhythm and autonomic nervous system in liver function: a hypothetical basis for improving the management of hepatic encephalopathy

Hepatic encephalopathy (HE) is a common, incapacitating complication of cirrhosis that affects many patients with cirrhosis. Although several therapies have proven effective in the treatment and prevention of this condition, several patients continue to suffer from covert disease or episodes of relapse. The circadian rhythm has been demonstrated to be pivotal for many body functions, including those of the liver. Here, we explore the impact of circadian rhythm-dependent signaling on the liver and discuss the evidence of its impact on liver pathology and metabolism. We describe the various pathways through which circadian influences are mediated. Finally, we introduce a novel method for improving patient response to drugs aimed at treating HE by utilizing the circadian rhythm. A digital system that introduces a customization-based technique for improving the response to therapies is presented as a hypothetical approach for improving the effectiveness of current medications used for the treatment of recurrent and persistent hepatic encephalopathy.

Study design for a three-arm equivalence clinical trial with binomially distributed outcomes

Equivalence in a clinical trial may be assessed through a three-arm trial (test drug, reference drug, and placebo). A three-arm equivalence trial consists of three hypothesis tests in practice, with two hypothesis tests demonstrating the superiority of the test and reference drugs against placebo, and the other one demonstrating the equivalence of the test and reference drugs. When designing a three-arm equivalence clinical trial, the practitioner should minimize the chances that a test drug will be found to be equivalent to the reference drug but non-superior to the placebo. One way to minimize these chances at the design stage, for a three-arm equivalence trial with a binary primary outcome, is to test the equivalence through hypotheses based upon the ratio of the differences of the proportions. In this article, we derived the test statistics and the power functions based on maximum likelihood estimate (MLE) and restricted MLE for the proposed hypotheses. The required sample size for achieving the desired power at the given significance level can be obtained by solving the power function. We illustrated the proposed design through an example and investigated the required sample sizes for various conditions.

Gastrointestinal Disorders and the Nervous System

PURPOSE OF REVIEW

This article describes the neurologic sequelae of various nutritional micronutrient deficiencies, celiac disease, inflammatory bowel disease, and liver disease. Where relevant, appropriate treatments for these conditions are also discussed. The developing field of the microbiome and nervous system interaction is also outlined.

RECENT FINDINGS

Pathology in the gastrointestinal system can affect the nervous system when it causes micronutrient deficiency, when immune responses created by the gastrointestinal system affect the nervous system, when toxins caused by gastrointestinal organ failure harm the nervous system, and when treatments aimed at a gastrointestinal medical condition cause damage to the nervous system as a side effect.

SUMMARY

This article addresses familiar concepts and new developments in the treatment and understanding of diseases that affect the gut and nervous system simultaneously.

Intestinal permeability and bacterial translocation in patients with liver disease, focusing on alcoholic aetiology: methods of assessment and therapeutic intervention

Increased bacterial translocation (BT) across the gut barrier due to greater intestinal permeability (IP) is seen across a range of conditions, including alcohol-related liver disease (ArLD). The phenomenon of BT may contribute to both the pathogenesis and the development of complications in ArLD. There are a number of methods available to assess IP and in this review we look at their various advantages and limitations. The knowledge around BT and IP in ArLD is also reviewed, as well as the therapeutic strategies currently in use and in development.

Efficacy of rifaximin in the different clinical scenarios of hepatic encephalopathy

Hepatic encephalopathy is a frequent complication in patients with cirrhosis of the liver and is associated with a high mortality rate. Costs attributed to the management of patients with cirrhosis are especially high due to complications, such as hepatic encephalopathy, given that they increase the number of days of hospital stay. Different drugs are currently used to treat hepatic encephalopathy, and the main ones are lactulose, L-ornithine L-aspartate (LOLA), and certain antibiotics, especially rifaximin-α (RFX). Even though many of them have been shown to be effective to greater or lesser degrees, it is important to understand the differences between them, so that every patient receives individualized treatment and the best option is chosen, in accordance with the different clinical scenarios. Thus, the aim of the present study was to analyze the evidence on the advantages and disadvantages of the individual or combined use of the 3 main treatments for hepatic encephalopathy, specifically taking into consideration their different degrees of efficacy, their impact on quality of life, prophylaxis, and cost reduction.

Topical antimicrobial therapy: Current status and challenges

Topically applied antibacterial agents are widely used. Opinions regarding the clinical efficacy of topical antibiotics are conflicting, and for most indications, alternative oral therapies are available. Topical application has many potential advantages over systemic therapy that includes high and sustained concentrations of drug directly at the infected site, low quantity of antibiotic needed, better compliance, fewer systemic side effects and potentially less chance of antimicrobial resistance. Despite these advantages, an important concern has been the difficulty in monitoring antibiotic dosage and duration of therapy. Most topical preparations are applied on sites with pre-existing normal bacterial flora, and the detrimental effect of antibiotic on the 'good' bacteria is difficult to control. Unnecessary exposure of the resident microflora to high drug levels may select drug-resistant phenotypes. The number of antibiotics available and the quality and composition of the formulations recommended for topical drug delivery are improving. Their role in the prevention and treatment of locally invasive infections is established for many clinical conditions. However, there is still a lacuna in the availability of pharmacokinetic (PK) knowledge of these topical preparations and translation of the same to clinical practice. In addition, reporting the clinical outcome following the use of these agents and its analysis considering the recently proposed epidemiological cut-off value-based cut-offs are also areas which merit further research. In this review, we highlight the clinical utility and the PK aspects of topical antimicrobials in various infections. We also discuss the limitations of the current antimicrobial susceptibility testing (AST) protocols and new methods for AMST for topical agents.

Current and future pharmacological therapies for managing cirrhosis and its complications

Due to the restrictions of liver transplantation, complication-guided pharmacological therapy has become the mainstay of long-term management of cirrhosis. This article aims to provide a complete overview of pharmacotherapy options that may be commenced in the outpatient setting which are available for managing cirrhosis and its complications, together with discussion of current controversies and potential future directions. PubMed/Medline/Cochrane Library were electronically searched up to December 2018 to identify studies evaluating safety, efficacy and therapeutic mechanisms of pharmacological agents in cirrhotic adults and animal models of cirrhosis. Non-selective beta-blockers effectively reduce variceal re-bleeding risk in cirrhotic patients with moderate/large varices, but appear ineffective for primary prevention of variceal development and may compromise renal function and haemodynamic stability in advanced decompensation. Recent observational studies suggest protective, haemodynamically-independent effects of beta-blockers relating to reduced bacterial translocation. The gut-selective antibiotic rifaximin is effective for secondary prophylaxis of hepatic encephalopathy; recent small trials also indicate its potential superiority to norfloxacin for secondary prevention of spontaneous bacterial peritonitis. Diuretics remain the mainstay of uncomplicated ascites treatment, and early trials suggest alpha-adrenergic receptor agonists may improve diuretic response in refractory ascites. Vaptans have not demonstrated clinical effectiveness in treating refractory ascites and may cause detrimental complications. Despite initial hepatotoxicity concerns, safety of statin administration has been demonstrated in compensated cirrhosis. Furthermore, statins are suggested to have protective effects upon fibrosis progression, decompensation and mortality. Evidence as to whether proton pump inhibitors cause gut-liver-brain axis dysfunction is conflicting. Emerging evidence indicates that anticoagulation therapy reduces incidence and increases recanalisation rates of non-malignant portal vein thrombosis, and may impede hepatic fibrogenesis and decompensation. Pharmacotherapy for cirrhosis should be implemented in accordance with up-to-date guidelines and in conjunction with aetiology management, nutritional optimisation and patient education.

Cognition Predicts Quality of Life Among Patients With End-Stage Liver Disease

BACKGROUND

Impaired cognitive functioning and poor quality of life (QoL) are both common among patients with end-stage liver disease; however, it is unclear how these are related.

OBJECTIVE

This study examines how specific cognitive domains predict QoL among liver transplant candidates by replicating Stewart and colleagues' (2010) 3-factor model of cognitive functioning, and determining how variability in these cognitive domains predicts mental health and physical QoL.

METHODS

The sample included 246 patients with end-stage liver disease who were candidates for liver transplant at a large, Midwestern health care center. Measures, including the Repeatable Battery for the Assessment of Neuropsychological Status, Trail Making Test, Shipley Institute of Living Scale, Short-Form Health Survey-36 Version 2, and Hospital Anxiety and Depression Scale, comprised latent variables representing global intellectual functioning, psychomotor speed, and learning and memory functioning.

RESULTS

Confirmatory factor analysis results indicate that the 3-factor solution model comprised of global intellectual functioning, psychomotor speed, and learning and memory functioning fit the data well. Addition of physical and mental health QoL latent factors resulted in a structural model also with good fit. Results related physical QoL to global intellectual functioning, and mental health QoL to global intellectual functioning and psychomotor functioning.

CONCLUSIONS

Findings elucidate a relationship between cognition and QoL and support the use of routine neuropsychological screening with end-stage liver disease patients, specifically examining the cognitive domains of global intellectual, psychomotor, and learning and memory functioning. Subsequently, screening results may inform implementation of targeted interventions to improve QoL.

Post-Transjugular Intrahepatic Portosystemic Shunt Follow-Up and Management in the VIATORR Era

The transjugular intrahepatic portosystemic shunt (TIPS) is a non-selective portosystemic shunt created using endovascular techniques. The first TIPS was performed in Germany in 1988. The VIATORR self-expandable PTFE covered stent-graft (WL Gore, Flagstaff AZ) was approved by the FDA for a TIPS application in December of 2004. This stent-graft offers excellent shunt patency rates and it is possible that it has a beneficial effect on patient survival. Patient surveillance and post-procedural management have changed after the introduction of this stent-graft. This article presents the current management strategies that are followed at our Institution for patients who have undergone a TIPS procedure with a VIATORR stent graft including imaging follow-up, management of encephalopathy, medical management and nutritional aspects.

Clinical effects of ornithine aspartate combined with rifaximin in treatment of acute hepatic encephalopathy

AIM: To evaluate the clinical effects of ornithine aspartate combined with rifaximin in the treatment of hepatic encephalopathy with liver cirrhosis.

METHODS: Eighty cirrhotic patients with hepatic encephalopathy treated at the Second Hospital of Zhengzhou and He'nan Provincial People's Hospital from February 2014 to February 2015 were randomly divided into an ornithine aspartate treatment group (group A), a rifaximin treatment group (group B) and an ornithine aspartate plus rifaximin treatment group (group C). One week later, efficacy and the changes of blood ammonia concentration and hepatic functions were compared.

RESULTS: After seven days of treatment, the concentrations of blood ammonia, ALT and TBIL in groups A and B were significantly higher compared with those in group C (blood ammonia: 68.14 µmol/L ± 11.13 µmol/L, 85.22 µmol/L ± 11.19 µmol/L vs 45.16 µmol/L ± 11.18 µmol/L, t = 3.014, 2.011, P < 0.05, < 0.01; ALT: 89.21 U/L ± 11.14 U/L, 78.16 U/L ± 13.02 U/L vs 56.26 U/L ± 14.04 U/L, t = 2.106, 2.057, P < 0.05 for both; TBIL: 40.06 µmol/L ± 8.05 µmol/L, 43.22 µmol/L ± 8.122 µmol/L vs 34.09 µmol/L ± 6.18 µmol/L, t = 1.085, 1.024, P < 0.05 and < 0.01). The total effective rate and the improvement rate for the treatment group (85.00% and 55.00%, respectively) were significantly higher than those of groups A and B (P < 0.05 for all).

CONCLUSION: Ornithine aspartate combined with rifaximin in treatment of acute hepatic encephalopathy can effectively ameliorate clinical symptoms and improve the curative effect.

Pathophysiology and management of hepatic encephalopathy 2014 update: Ammonia toxicity and hyponatremia

Hyperammonemia is a major factor involved in the pathogenesis of hepatic encephalopathy (HE). Ammonia elicits astrocyte swelling and causes brain edema. In addition, hyponatremia, a condition frequently observed in hepatic cirrhosis, also exacerbates brain edema, potentially becoming a factor that exacerbates HE. Therefore, as a treatment strategy for HE, alleviating ammonia toxicity is essential. In addition to restricting protein intake, synthetic disaccharides such as lactulose and lactitol, probiotics that improve gut flora, and rifaximin, an antibiotic with poor bioavailability, are also administrated. Additionally, branched-chain amino acids and carnitine have also been administrated. Moreover, we investigated the current trend in the concomitant use of drugs with different mechanisms of action. In Japan, the V2 receptor antagonist tolvaptan can be administrated to hepatic cirrhosis patients with fluid retention. This drug is also useful as a countermeasure for hyponatremia in hepatic cirrhosis, and elucidating its effects in HE patients may therefore become an agenda in the future. These observations indicate that ammonia toxicity, gut flora control and low sodium control are major focuses in HE improvement and long-term prognosis.

Effect of rifaximin on gut microbiota composition in advanced liver disease and its complications

Liver cirrhosis is a paradigm of intestinal dysbiosis. The qualitative and quantitative derangement of intestinal microbial community reported in cirrhotic patients seems to be strictly related with the impairment of liver function. A kind of gut microbial "fingerprint", characterized by the reduced ratio of "good" to "potentially pathogenic" bacteria has recently been outlined, and is associated with the increase in Model for End-Stage Liver Disease and Child Pugh scores. Moreover, in patients presenting with cirrhosis complications such as spontaneous bacterial peritonitis (SBP), hepatic encephalopathy (HE), and, portal hypertension intestinal microbiota modifications or the isolation of bacteria deriving from the gut are commonly reported. Rifaximin is a non-absorbable antibiotic used in the management of several gastrointestinal diseases. Beyond bactericidal/bacteriostatic, immune-modulating and anti-inflammatory activity, a little is known about its interaction with gut microbial environment. Rifaximin has been demonstrated to exert beneficial effects on cognitive function in patients with HE, and also to prevent the development of SBP, to reduce endotoxemia and to improve hemodynamics in cirrhotics. These results are linked to a shift in gut microbes functionality, triggering the production of favorable metabolites. The low incidence of drug-related adverse events due to the small amount of circulating drug makes rifaximin a relatively safe antibiotic for the modulation of gut microbiota in advanced liver disease.

[Role of rifaximin in the treatment of hepatic encephalopathy]

Hepatic encephalopathy (HE) is a frequent and serious complication of liver cirrhosis. In addition to correction of the precipitating factors, the most commonly used treatments are non-absorbable disaccharides and rifaximin. Many of the recommendations are based on current clinical practice and there are few randomized controlled trials. Currently, rifaximin should be initiated during an episode of EH if, after 24-48 hours of non-absorbable disaccharide therapy, there is no clinical improvement. In recurrent EH, it is advisable to add rifaximin in patients under non-absorbable disaccharide therapy who develop a new episode. Currently, standard treatment with rifaximin for minimal EH is not recommended. Rifaximin is effective in the acute treatment of overt encephalopathy and in preventing recurrence.

Rifaximin for prevention and treatment of hepatic encephalopathy

Hepatic encephalopathy (HE) is a serious neuropsychiatric syndrome of the central nervous system caused by liver failure or portosystemic shunt, seriously affecting patients' physical and mental well being. Although the pathogenesis of HE is still unclear at present, ammonia poisoning is believed to play a dominant role. Thus, reduction of ammonia is an important treatment for HE. This paper discusses the role of rifaximin in the prevention and treatment of HE.