Double-blind, double-dummy comparison between treatment with rifaximin and lactulose in patients with medium to severe degree hepatic encephalopathy

Rifaximin for prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Hepatic encephalopathy describes the spectrum of neuropsychiatric changes that may complicate the course of cirrhosis and detrimentally affect outcomes. Ammonia plays a key role in its development. Rifaximin is a non-absorbable antibiotic that inhibits urease-producing bacteria and reduces absorption of dietary and bacterial ammonia.

OBJECTIVES

To evaluate the beneficial and harmful effects of rifaximin versus placebo, no intervention, or non-absorbable disaccharides for: (i) the prevention of hepatic encephalopathy, and (ii) the treatment of minimal and overt hepatic encephalopathy, in people with cirrhosis, both when used alone and when combined with a non-absorbable disaccharide.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Clinical Trials Register, CENTRAL, MEDLINE, Embase, three other databases, the reference lists of identified papers, and relevant conference proceedings. We wrote to authors and pharmaceutical companies for information on other published, unpublished, or ongoing trials. Searches were performed to January 2023.

SELECTION CRITERIA

We included randomised clinical trials assessing prevention or treatment of hepatic encephalopathy with rifaximin alone, or with a non-absorbable disaccharide, versus placebo/no intervention, or a non-absorbable disaccharide alone.

DATA COLLECTION AND ANALYSIS

Six authors independently searched for studies, extracted data, and validated findings. We assessed the design, bias risk, and participant/intervention characteristics of the included studies. We assessed mortality, serious adverse events, health-related quality of life, hepatic encephalopathy, non-serious adverse events, blood ammonia, Number Connection Test-A, and length of hospital stay.

MAIN RESULTS

We included 41 trials involving 4545 people with, or at risk for, developing hepatic encephalopathy. We excluded 89 trials and identified 13 ongoing studies. Some trials involved participants with more than one type of hepatic encephalopathy or more than one treatment comparison. Hepatic encephalopathy was classed as acute (13 trials), chronic (7 trials), or minimal (8 trials), or else participants were considered at risk for its development (13 trials). The control groups received placebo (12 trials), no/standard treatment (1 trial), or a non-absorbable disaccharide (14 trials). Eighteen trials assessed rifaximin plus a non-absorbable disaccharide versus a non-absorbable disaccharide alone. We classified 11 trials as at high risk of overall bias for mortality and 28 for non-mortality outcomes, mainly due to lack of blinding, incomplete outcome data, and selective reporting. Compared to placebo/no intervention, rifaximin likely has no overall effect on mortality (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.50 to 1.38; P = 48, I2 = 0%; 13 trials, 1007 participants; moderate-certainty evidence), and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.99, 95% CI 0.49 to 1.97; P = 0.97, I2 = 0%; 10 trials, 786 participants; low-certainty evidence). However, there is likely a reduction in the overall risk of mortality when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.69, 95% CI 0.55 to 0.86; number needed to treat for an additional beneficial outcome (NNTB) = 22; P = 0.001, I2 = 0%; 14 trials, 1946 participants; moderate-certainty evidence). There is likely no effect on the overall risk of serious adverse events when comparing rifaximin to placebo/no intervention (RR 1.05, 95% CI 0.83 to 1.32; P = 68, I2 = 0%; 9 trials, 801 participants; moderate-certainty evidence) and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.97, 95% CI 0.66 to 1.40; P = 85, I2 = 0%; 8 trials, 681 participants; low-certainty evidence). However, there was very low-certainty evidence that use of rifaximin plus a non-absorbable disaccharide may be associated with a lower risk of serious adverse events than use of a non-absorbable disaccharide alone (RR 0.66, 95% CI 0.45 to 0.98; P = 0.04, I2 = 60%; 7 trials, 1076 participants). Rifaximin likely results in an overall effect on health-related quality of life when compared to placebo/no intervention (mean difference (MD) -1.43, 95% CI -2.87 to 0.02; P = 0.05, I2 = 81%; 4 trials, 214 participants; moderate-certainty evidence), and may benefit health-related quality of life in people with minimal hepatic encephalopathy (MD -2.07, 95% CI -2.79 to -1.35; P < 0.001, I2 = 0%; 3 trials, 176 participants). The overall effect on health-related quality of life when comparing rifaximin to non-absorbable disaccharides is very uncertain (MD -0.33, 95% CI -1.65 to 0.98; P = 0.62, I2 = 0%; 2 trials, 249 participants; very low-certainty evidence). None of the combined rifaximin/non-absorbable disaccharide trials reported on this outcome. There is likely an overall beneficial effect on hepatic encephalopathy when comparing rifaximin to placebo/no intervention (RR 0.56, 95% CI 0.42 to 0.77; NNTB = 5; P < 0.001, I2 = 68%; 13 trials, 1009 participants; moderate-certainty evidence). This effect may be more marked in people with minimal hepatic encephalopathy (RR 0.40, 95% CI 0.31 to 0.52; NNTB = 3; P < 0.001, I2 = 10%; 6 trials, 364 participants) and in prevention trials (RR 0.71, 95% CI 0.56 to 0.91; NNTB = 10; P = 0.007, I2 = 36%; 4 trials, 474 participants). There may be little overall effect on hepatic encephalopathy when comparing rifaximin to non-absorbable disaccharides (RR 0.85, 95% CI 0.69 to 1.05; P = 0.13, I2 = 0%; 13 trials, 921 participants; low-certainty evidence). However, there may be an overall beneficial effect on hepatic encephalopathy when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.58, 95% CI 0.48 to 0.71; NNTB = 5; P < 0.001, I2 = 62%; 17 trials, 2332 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Compared to placebo/no intervention, rifaximin likely improves health-related quality of life in people with minimal hepatic encephalopathy, and may improve hepatic encephalopathy, particularly in populations with minimal hepatic encephalopathy and when it is used for prevention. Rifaximin likely has no overall effect on mortality, serious adverse events, health-related quality of life, or hepatic encephalopathy compared to non-absorbable disaccharides. However, when used in combination with a non-absorbable disaccharide, it likely reduces overall mortality risk, the risk of serious adverse events, improves hepatic encephalopathy, reduces the length of hospital stay, and prevents the occurrence/recurrence of hepatic encephalopathy. The certainty of evidence for these outcomes is very low to moderate; further high-quality trials are needed.

Rifaximin Improves Liver Functional Reserve by Regulating Systemic Inflammation

Rifaximin, a non-absorbable antibiotic, has been demonstrated to be effective against hepatic encephalopathy (HE); however, its efficacy on liver functional reserve remains unknown. Here, we evaluated the efficacy of rifaximin on the liver functional reserve and serological inflammation-based markers in patients with cirrhosis. A retrospective study was conducted on patients who received rifaximin for more than three months at our hospital between November 2016 and October 2021. The recurrence and grade of HE, serological ammonia levels, Child–Pugh score (CPS), and serological inflammation-based markers such as the neutrophil–lymphocyte ratio (NLR), lymphocyte–monocyte ratio (LMR), platelet–lymphocyte ratio (PLR), C-reactive protein (CRP), and CRP to albumin ratio (CAR) were evaluated. The correlations between serological inflammation-based markers and liver functional reserve were evaluated. HE grades, serum ammonia levels, and inflammation-based markers significantly improved at three months compared with those at baseline. Patients with improved albumin levels showed significantly higher CRP improvement rates at both 3 and 12 months. Patients with an improvement in CAR at 3 months demonstrated a significant improvement in CPS at 12 months. Rifaximin improved the liver functional reserve in patients with cirrhosis. Improvements in inflammation-based markers, particularly CRP and albumin, may be involved in this process.

Efficacy and Safety of Rifaximin Versus Placebo or Other Active Drugs in Critical ill Patients With Hepatic Encephalopathy

Objective: Rifaximin has been approved for use as a first-line therapy for secondary prophylaxis of hepatic encephalopathy (HE). This article is to update existing evidence on efficacy and safety of rifaximin treatment and prevention for HE.

Methods: We systematically searched multiple databases until January 31 2021. The studies compared rifaximin vs. placebo or other active drugs (i.e., nonabsorbable disaccharides, other antibiotics, L-ornithine-L-aspartate (LOLA), and probiotics) for patients with overt HE (OHE), minimal HE (MHE), and recurrent HE.

Results: Twenty-eight randomized controlled trials with a total of 2979 patients were included. Compared with the controls, rifaximin significantly reduced HE grade (OHE: RR = 1.11, 95% CI = 1.02–1.21), improved the cognitive impairments (MHE: RR = 1.82, 95% CI = 1.12–2.93) and prevented the risk of HE recurrent episodes (RR = 1.33, 95% CI = 1.18–1.49). No statistical difference was observed in mortality between rifaximin and their controls (RR = 0.82, 95% CI = 0.54–1.24). The incidence of total adverse events in rifaximin-treated groups was significantly lower than that in the controls during the treatment period (RR = 0.73, 95% CI = 0.54–0.98). In addition, rifaximin treatment was better than other active drugs in improving psychometric indicators (mental state, flapping tremor and portosystemic encephalopathy (PSE) index) and reducing the risk of rehospitalization in HE patients.

Conclusion: Rifaximin therapy is effective and well-tolerated in different types of HE, which might be recommended as an alternative to conventional oral drugs in clinical settings.

Hepatic encephalopathy: Novel insights into classification, pathophysiology and therapy

Hepatic encephalopathy (HE) is a frequent and serious complication of both chronic liver disease and acute liver failure. HE manifests as a wide spectrum of neuropsychiatric abnormalities, from subclinical changes (mild cognitive impairment) to marked disorientation, confusion and coma. The clinical and economic burden of HE is considerable, and it contributes greatly to impaired quality of life, morbidity and mortality. This review will critically discuss the latest classification of HE, as well as the pathogenesis and pathophysiological pathways underlying the neurological decline in patients with end-stage liver disease. In addition, management strategies, diagnostic approaches, currently available therapeutic options and novel treatment strategies are discussed.

Non-Lactulose Medication Therapies for the Management of Hepatic Encephalopathy: A Literature Review

OBJECTIVE

The most appropriate medication regimen to mitigate the consequences hepatic encephalopathy remains inconclusive. This review seeks to serve as a reference for clinicians to help guide therapy decisions with regard to hepatic encephalopathy.

METHODS

A comprehensive literature review between August 2018 and April 2019 was accomplished with the assistance of a medical librarian. Sources of literature review include PubMed, MEDLINE, SCOPUS, ProQuest Central, CINAHL, and ProQuest Dissertations. The authors selected randomized clinical and double-blind cross-over trials evaluating probiotics, zinc, polyethylene glycol, rifaximin, and flumazenil. Sixteen clinical trials are discussed in this review. Pertinent safety, efficacy, and statistical and clinical outcomes are summarized by the authors.

CONCLUSIONS

The most appropriate regimen to mitigate the consequences of hepatic encephalopathy remains elusive; however, the agents discussed within this review offer alternative options for patients unresponsive to or intolerant of traditional lactulose therapy. This review seeks to serve as a repository for relevant clinical trials, and as a reference for clinicians to help guide therapy decisions.

Pathophysiology of hepatic encephalopathy and future treatment options

Understanding of the pathophysiology of hepatic encephalopathy has conditioned new treatment options. Ammonia detoxification in hepatic encephalopathy is regulated by two enzymes: glutaminase or glutamine synthetase. The first produces ammonia and the second detoxifies the ammonia, which is why treatments are aimed at glutaminase inhibition or glutamine synthetase activation. At present, we know that both enzymes are found not only in the liver, but also in the muscle, intestine, kidney, and brain. Therefore, current treatments can be directed at each enzyme at different sites. Awareness of those potential treatment sites makes different options of approach possible in the patient with hepatic encephalopathy, and each approach should be personalized.

New concepts on intestinal microbiota and the role of the non-absorbable antibiotics with special reference to rifaximin in digestive diseases

Digestive diseases are a broad range of chronic disorders that substantially and negatively impact the patients' quality of life. Here, we review our current understanding on the pathophysiology of hepatic encephalopathy, irritable bowel syndrome, and diverticular disease, with a special focus on the gut microbiota composition associated with these disorders. Furthermore, we review the current clinical practice for their therapeutic treatments, including probiotics, diet change, non-adsorbable disaccharides, and antibiotics. We highlight that broad-spectrum non-adsorbable antibiotics, such as rifaximin, are quite effective and safe for the treatment of all essayed digestive diseases.

Review article: potential mechanisms of action of rifaximin in the management of hepatic encephalopathy and other complications of cirrhosis

BACKGROUND

Progressive gut milieu (microbiota) changes occur in patients with cirrhosis and are associated with complications [e.g. hepatic encephalopathy (HE)].

AIM

To examine the role of rifaximin in the management of HE and other complications of cirrhosis, including potential mechanisms of action and the need for future studies.

METHODS

A literature search was conducted using the keywords 'rifaximin', 'hepatic encephalopathy', 'ascites', 'variceal bleeding', 'peritonitis', 'portal hypertension', 'portopulmonary hypertension' and 'hepatorenal syndrome'.

RESULTS

The nonsystemic agent rifaximin reduces the risk of HE recurrence and HE-related hospitalisations in cirrhosis. In patients with cirrhosis, rifaximin modulates the bacterial composition of the gut microbiota without a consistent effect on overall faecal microbiota composition. However, rifaximin can impact the function or activities of the gut microbiota. For example, rifaximin significantly increased serum levels of long-chain fatty acids and carbohydrate metabolism intermediates in patients with minimal HE. Rifaximin also favourably affects serum proinflammatory cytokine and faecal secondary bile acid levels.

CONCLUSIONS

The gut microenvironment and associated microbiota play an important role in the pathogenesis of HE and other cirrhosis-related complications. Rifaximin's clinical activity may be attributed to effects on metabolic function of the gut microbiota, rather than a change in the relative bacterial abundance.

[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.

Covert and Overt Hepatic Encephalopathy: Diagnosis and Management

Hepatic encephalopathy (HE) is part of a spectrum of neurocognitive changes in cirrhosis. HE is divided into 2 broad categories based on severity: covert hepatic encephalopathy (CHE) and overt hepatic encephalopathy (OHE). CHE has a significant impact on a patient's quality of life, driving performance, and recently has been associated with increased hospitalizations and death. Likewise, OHE is associated with increased rates of hospitalizations and mortality, and poor quality of life. Given its significant burden on patients, care takers, and the health care system, early diagnosis and management are imperative. In addition, focus also should be directed on patient and family member education on the disease progression and adherence to medications. Treatment strategies include the use of nonabsorbable disaccharides, antibiotics (ie, rifaximin), and, potentially, probiotics. Other therapies currently under further investigation include L-ornithine-L-aspartate, ornithine phenylacetate, glycerol phenylbutyrate, molecular adsorbent recirculating system, and albumin infusion.

Clinical and pathophysiological consequences of alterations in the microbiome in cirrhosis

Cirrhosis is a major cause of mortality worldwide. Exponential rises in prevalence have been observed secondary to increases in obesity and alcohol consumption. Multiple lines of evidence implicate gut-derived bacteria and bacterial ligands as a central driver of pathogenesis. Recent developments in culture-independent techniques have facilitated a more accurate description of microbiome composition in cirrhosis and led to the description of measures of dysbiosis shown to be associated with disease. More importantly, metagenomic studies are adding to an understanding of the functional contribution of the microbiota and may prove to be a more clinically relevant biomarker than phylogenetic studies. Much like other dysbiotic states such as inflammatory bowel disease, the microbiota in cirrhosis is characterized by a low microbial and genetic diversity. Therapeutic strategies to diminish this process are currently limited to selective intestinal decontamination with antibiotics. This review summarizes the available data and develops a framework for the use of current and future treatment strategies to diminish the consequences of dysbiosis in cirrhosis. Interventional strategies to bind bacterial products in the gut lumen and blood, and modulate the magnitude of host sensing mechanisms remain an unmet clinical need. A greater understanding of the host-microbiota interaction in cirrhosis is of key importance to inform future interventional strategies to diminish the currently escalating burden of the disease.

Efficacy and tolerability of rifaximin in combination with lactulose in end-stage liver disease patients with MELD greater than 20: a single center experience

BACKGROUND

Rifaximin is a non-absorbable antibiotic which is approved for the treatment of hepatic encephalopathy (HE) in the United States. Our goal was to retrospectively assess this in patients with very advanced liver disease with our center data.

METHODS

Between 2003 and 2010, we examined a total of 286 consecutive patients from our center who were on a combination of rifaximin and lactulose, who had been evaluated or listed as eligible for a liver transplant. Patients who received less than 3 months of rifaximin and lactulose were excluded. Patients who had incomplete data; specifically, a lack of MELD score upon hospital admission were excluded from this analysis. The retrospective chart review was approved by the institutional review board.

RESULTS

We observed a total of 723 hospitalizations among the patients. Of the 723 hospitalizations, 218 were due to portosystemic encephalopathy (PSE), whereas 505 were due to other causes. We observed that patients with a MELD < 20 had an average of 2.5 hospitalizations per 6 month period, and that those with a MELD > 20 had an average of 1.6 hospitalizations per 6 month period for HE. At the same time, patients who had a MELD score < 20 had 3.29 hospitalizations for HE unrelated causes and those whose MELD was >20 had 3.73 hospitalizations for causes not related to HE. In this cohort 65% of all hospitalizations from HE were in patients whose MELD was < 20, and 35% of all hospitalizations were for patients with a MELD > 20.

CONCLUSION

In our experience, HE related hospitalizations were lower in patients whose MELD > 20 who were on a combination of rifaximin and lactulose compared to patients with MELD < 20. In contrast, patients whose MELD > 20 had greater hospitalizations for non HE events which may be an expected result owing to the overall increased severity of their liver disease. The limitation of this study is its retrospective nature and single center experience. In conclusion, administration of rifaximin appears to significantly reduce hospitalizations from HE in patients with MELD > 20 and therefore is advocated in maintenance of remission of HE in patients with very advanced liver disease.

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.

Systematic review with network meta-analysis: the comparative effectiveness and safety of interventions in patients with overt hepatic encephalopathy

BACKGROUND

Interventional treatment for overt hepatic encephalopathy (OHE), includes non-absorbable disaccharides, neomycin, rifaximin, L-ornithine-L-aspartate and branched chain amino acids (BCAA). However, the optimum regimen remains inconclusive.

AIM

To compare interventions in terms of patients' adverse events and major clinical outcomes.

METHODS

Literature search of PubMed, Embase, Scopus, and Cochrane Library studies published up to July 31 2014. RCTs of above interventions in OHE patients were included. Network meta-analysis combined direct and indirect evidence to estimate odds ratios (ORs) and mean difference (MD) between treatments and the probabilities of ranking for treatment based on clinical outcomes.

RESULTS

Twenty eligible RCTs were included. When compared with observation, only L-ornithine-L-aspartate (OR 3.71, P < 0.001) and BCAA (OR 3.37, P < 0.001) improved clinical efficacy significantly. However, when L-ornithine-L-aspartate was compared with BCAA, non-absorbable disaccharides and neomycin, there was a trend suggesting that L-ornithine-L-aspartate may be the most effective intervention with respect to clinical improvement (OR 1.10), rifaximin (OR 1.31), non-absorbable disaccharides (OR 2.75), neomycin (OR 2.22). In addition, L-ornithine-L-aspartate (MD -20.18, 95% CI -40.12 to -0.27) provided a significant reduction in blood ammonia concentration compared with observation. Neomycin appeared to be associated with more adverse events in comparison with non-absorbable disaccharides (OR 10.15), rifaximin (OR 17.31), L-ornithine-L-aspartate (OR 3.16) or BCAA (OR 7.69).

CONCLUSIONS

L-ornithine-L-aspartate treatment may show a trend in superiority for clinical efficacy among standard interventions for OHE. Rifaximin shows the greatest reduction in blood ammonia concentration, and treatment with neomycin demonstrates a higher probability in causing adverse effects among the five compared interventions.

Gut-liver axis in liver cirrhosis: How to manage leaky gut and endotoxemia

A “leaky gut” may be the cutting edge for the passage of toxins, antigens or bacteria into the body, and may play a pathogenic role in advanced liver cirrhosis and its complications. Plasma endotoxin levels have been admitted as a surrogate marker of bacterial translocation and close relations of endotoxemia to hyperdynamic circulation, portal hypertension, renal, cardiac, pulmonary and coagulation disturbances have been reported. Bacterial overgrowth, increased intestinal permeability, failure to inactivate endotoxin, activated innate immunity are all likely to play a role in the pathological states of bacterial translocation. Therapeutic approach by management of the gut-liver axis by antibiotics, probiotics, synbiotics, prebiotics and their combinations may improve the clinical course of cirrhotic patients. Special concern should be paid on anti-endotoxin treatment. Adequate management of the gut-liver axis may be effective for prevention of liver cirrhosis itself by inhibiting the progression of fibrosis.

Managing complications in cirrhotic patients

Liver cirrhosis is a serious and potentially life-threatening condition. This life-threatening condition usually arises from complications of cirrhosis. While variceal bleeding is the most acute and probably best studied, several other complications of liver cirrhosis are more insidious in their onset but nevertheless more important for the long-term management and outcome of these patients. This review summarizes the topics discussed during the UEG-EASL Hepatology postgraduate course of the United European Gastroenterology Week 2013 and discusses emergency surgical conditions in cirrhotic patients, the management of hepatic encephalopathy, ascites and hepatorenal syndrome, coagulation disorders, and liver cancer.

Systematic review with meta-analysis: the effects of rifaximin in hepatic encephalopathy

BACKGROUND

Rifaximin is recommended for prevention of hepatic encephalopathy (HE). The effects of rifaximin on overt and minimal HE are debated.

AIM

To perform a systematic review and meta-analysis of randomised controlled trials (RCTs) on rifaximin for HE.

METHODS

We performed electronic and manual searches, gathered information from the U.S. Food and Drug Administration Home Page, and obtained unpublished information on trial design and outcome measures from authors and pharmaceutical companies. Meta-analyses were performed and results presented as risk ratios (RR) with 95% confidence intervals (CI) and the number needed to treat. Subgroup, sensitivity, regression and sequential analyses were performed to evaluate the risk of bias and sources of heterogeneity.

RESULTS

We included 19 RCTs with 1370 patients. Outcomes were recalculated based on unpublished information of 11 trials. Overall, rifaximin had a beneficial effect on secondary prevention of HE (RR: 1.32; 95% CI 1.06-1.65), but not in a sensitivity analysis on rifaximin after TIPSS (RR: 1.27; 95% CI 1.00-1.53). Rifaximin increased the proportion of patients who recovered from HE (RR: 0.59; 95% CI: 0.46-0.76) and reduced mortality (RR: 0.68, 95% CI 0.48-0.97). The results were robust to adjustments for bias control. No small study effects were identified. The sequential analyses only confirmed the results of the analysis on HE recovery.

CONCLUSIONS

Rifaximin has a beneficial effect on hepatic encephalopathy and may reduce mortality. The combined evidence suggests that rifaximin may be considered in the evidence-based management of hepatic encephalopathy.

Hepatic Encephalopathy: From the Pathogenesis to the New Treatments

Hepatic encephalopathy is a frequent and serious complication of liver cirrhosis; the pathophysiology of this complication is not fully understood although great efforts have been made during the last years. There are few prospective studies on the epidemiology of this complication; however, it is known that it confers with high short-term mortality. Hepatic encephalopathy has been classified into different groups depending on the degree of hepatic dysfunction, the presence of portal-systemic shunts, and the number of episodes. Due to the large clinical spectra of overt EH and the complexity of cirrhotic patients, it is very difficult to perform quality clinical trials for assessing the efficacy of the treatments proposed. The physiopathology, clinical manifestation, and the treatment of HE is a challenge because of the multiple factors that converge and coexist in an episode of overt HE.

Clinical effects of rifaximin in patientswith hepatic encephalopathy intolerant or nonresponsive to previous lactulose treatment: An open-label, pilot study

BACKGROUND

Hepatic encephalopathy (HE) is a metabolic-neurophysiologicsyndrome that occurs in patients with advanced hepatic disease. One of the main pathogenic mechanisms is represented by circulating toxins produced by the intestinal metabolism of nitrogenous compounds. The therapeutic approach to HE is mainly based on drugs that eliminate ammonia-producing bacteria.

OBJECTIVES

The aim of this study was to evaluate the effects of the nonabsorbable antibiotic rifaximin in patients with HE who were intolerant or nonresponsive to treatment with an oral, nonabsorbable disaccharide (lactulose).

METHODS

This uncontrolled, open-label, pilot study was conducted at the University of Bologna, Bologna, Italy. Patients aged ≥ 18 years with histologically proven liver cirrhosis and HE were studied. All patients were intolerant or nonresponsive to previous treatment with lactulose. Rifaximin tablets were administered to patients at a dosage of 400 mg TID for 10 days. The portal systemic encephalopathy (PSE) index was evaluated at enrollment and at the end of the treatment period. Tolerability was assessed using hematology, biochemistry, and urinalysis and by recording adverse effects (AEs).

RESULTS

Twenty-six patients (18 men, 8 women; mean [SD] age, 55.8 [8.0] years) were enrolled (intolerants, n = 17; nonresponders, n = 9). All patients completed the study. Significant improvement was shown in most of the 5 components of the PSE index after rifaximin administration in both intolerants and nonresponders. At the end of the 10-day treatment period, the PSE index was significantly reduced in both intolerants and nonresponders. Rifaximin was well tolerated; no clinically relevant AEs were observed during the treatment period.

CONCLUSIONS

This pilot study of patients with liver cirrhosis and HE who were intolerant or nonresponsive to previous treatment with an oral, nonabsorbable disaccharide suggests that treatment with rifaximin may be considered as an adjuvant or an alternative treatment in reducing HE.

Management of hepatic encephalopathy in the hospital

Hepatic encephalopathy (HE) develops in up to 50% of patients with cirrhosis and is a feature of decompensated cirrhosis. With the goal of reviewing the evidence for treatment and prevention of overt hepatic encephalopathy, pubmed was searched using search terms hepatic encephalopathy AND treatment, limited to human studies from January 1, 2003, through December 1, 2013, and supplemented by key references. The inpatient incidence of HE is approximately 23,000 annually, and management of these patients is common for internists and subspecialists. Treatment of the hospitalized patient with HE has changed in recent years. Treatment entails 2 phases: induction and maintenance of remission. Most cases of significant HE are precipitated by infection, gastrointestinal bleeding, medications, or other culprits. All patients should be evaluated for secondary triggers of HE, and treatment should be initiated with a nonabsorbable disaccharide (ie, lactulose) in most patients. Rifaximin (off label) can be added in patients not responding to lactulose. Neomycin is a less preferred alternative to rifaximin owing to its adverse effect profile. Other therapies, including zinc, L-ornithine-L-aspartate, and branched-chain amino acids, can be considered for patients not responding to disaccharides and nonabsorbable antibiotics. Large portosystemic shunts may be embolized in patients with medically refractory recurrent or severe HE with otherwise well-compensated cirrhosis. Molecular Adsorbent Recirculating System is now available for patients with severe HE who do not respond to medical therapy. It is critically important that patients hospitalized with significant HE continue maintenance therapy at the time of dismissal to prevent further episodes. Patients with a first-time episode of HE can be administered lactulose, and careful instructions should be provided to patients and caregivers about dose titration to achieve 3 bowel movements daily. Patients with recurrent HE episodes despite lactulose use benefit from the addition of rifaximin, which decreases the frequency of recurrent HE episodes and related hospitalizations. Last, patients and their families should be counseled about the risk of motor vehicle accidents, which require mandatory reporting to the Department of Motor Vehicles in some states.

Safety, efficacy, and patient acceptability of rifaximin for hepatic encephalopathy

Hepatic encephalopathy is a complex disease entity ranging from mild cognitive dysfunction to deep coma. Traditionally, treatment has focused on a reduction of ammonia through a reduced production, absorption, or clearance. Rifaximin is a nonabsorbable antibiotic, which reduces the production of ammonia by gut bacteria and, to some extent, other toxic derivatives from the gut. Clinical trials show that these effects improve episodes of hepatic encephalopathy. A large randomized trial found that rifaximin prevents recurrent episodes of hepatic encephalopathy. Most patients were treated concurrently with lactulose. Trials have varied greatly in design, outcomes, and duration of treatment regimes. Although a number of retrospective studies have indicated that long-term treatment with rifaximin is safe and possibly beneficial, high quality trials are needed to further clarify efficacy and safety of long-term treatment with rifaximin and evaluate effects of combination therapy with lactulose and branched-chain amino acids for patients with liver cirrhosis and hepatic encephalopathy.

Ammonia clearance with haemofiltration in adults with liver disease

BACKGROUND & AIMS

Ammonia is recognized as a toxin central to complications of liver failure. Hyperammonaemia has important clinical consequences, but optimal means to reduce circulating levels are uncertain. In patients with liver disease, continuous renal replacement therapy (CRRT) with haemofiltration (HF) is often required to treat concurrent kidney injury, but its effects upon ammonia levels are poorly characterized. To evaluate the effect of HF at different treatment intensities on ammonia clearance (AC) and arterial ammonia concentration.

METHODS

Prospective study of adult patients with liver failure and arterial ammonia >100 μmol/L requiring CRRT using veno-venous HF. Arterial ammonia concentration and AC measured at 1 and 24 h after initiation of low (35 ml/kg/h) or high (90 ml/kg/h) filtration volume.

RESULTS

Twenty-four patients (10 acute liver failure, 10 chronic liver disease and 4 following liver resection) were studied. Clearance of urea and ammonia solutes correlated closely (r = 0.819, P = 0.007). Ammonia clearance correlated closely with ultrafiltration rate (r = 0.86, P < 0.001). At 1 h, AC was 39 (34-54) ml/min (low volume) vs 85 (62-105) ml/min (high volume) CRRT, (P < 0.001) and at 24 h 44 (34-63) vs 105 (82-109) ml/min, (P = 0.01). Overall, a 22% reduction in median arterial ammonia concentration was observed over 24 h of HF from 156 (137-176) to 122 (85-133) μmol/L, (P ≤ 0.0001).

CONCLUSION

Clinically significant ammonia clearance can be achieved in adult patients with hyperammonaemia utilizing continuous VVHF. Ammonia clearance is closely correlated with ultrafiltration rate. HF was associated with a fall in arterial ammonia concentration.

Recent insights into the pathogenesis of hepatic encephalopathy and treatments

Hepatic encephalopathy (HE) encompasses a spectrum of neuropsychiatric disorders related to liver failure. The development of HE can have a profound impact on mortality as well as quality of life for patients and carers. Ammonia is central in the disease process contributing to alteration in neurotransmission, oxidative stress, and cerebral edema and astrocyte swelling in acute liver failure. Inflammation in the presence of ammonia coactively worsens HE. Inflammation can result from hyperammonemic responses, endotoxemia, innate immune dysfunction or concurrent infection. This review summarizes the current processes implicated in the pathogenesis of HE, as well as current and potential treatments. Treatments currently focus on reducing inflammation and/or blood ammonia levels and provide varying degrees of success. Optimization of current treatments and initial testing of novel therapies will provide the basis of improvement of care in the near future.

Microbiota-liver axis in hepatic disease

Accumulating evidence indicates that the gut microbiota, long appreciated to be a key determinant of intestinal inflammation, is also playing a key role in chronic inflammatory disease of the liver. Such studies have yielded a general central hypothesis whereby microbiota products activate the innate immune system to drive proinflammatory gene expression, thus promoting chronic inflammatory disease of the liver. This article reviews the background supporting this hypothesis, outlines how it can potentially explain classic and newly emerging epidemiological chronic inflammatory liver disease, and discusses potential therapeutic means to manipulate the microbiota so as to prevent and/or treat liver disease.

Update on management of patients with overt hepatic encephalopathy

Hepatic encephalopathy (HE) is a multifactorial neuropsychiatric disease that affects patients with cirrhosis. We review the clinical impact, pathogenesis, evaluation, management, and prevention of overt HE in patients with cirrhosis. Articles published between January 1960 and November 2012 were acquired through a MEDLINE search of different combinations of the terms hepatic encephalopathy, pathophysiology, treatment, prophylaxis, prevention, prognosis, and recurrence. The Healthcare Cost and Utilization Project database was used to obtain prevalence and cost information related to hospitalizations of patients with HE. The literature describes significant morbidity and mortality of HE in patients with cirrhosis. Overt HE develops in 30% to 45% of patients with cirrhosis and is associated with a substantial pharmacoeconomic burden, particularly HE-related hospitalizations. The development of HE in patients with cirrhosis portends a worsened prognosis and is incorporated into the Child-Pugh classification of the severity of liver disease. In the hospitalized patient, the development of HE is associated with precipitating events (eg, gastrointestinal bleeding, dehydration, infection), and in some patients, its course is characterized by frequent and severe relapses. In addition, hospitalized patients with overt HE have a 3.9-fold increased mortality risk. Patient management employs nonabsorbable disaccharides, the nonsystemic antibiotic rifaximin, or both, to treat acute HE episodes and prevent HE relapse. In open-label trials, use of the nonabsorbable disaccharide lactulose reduced the risk of overt HE recurrence in patients compared with no-lactulose control groups for ≤ a median of 14 months. In a randomized, placebo-controlled trial, rifaximin 550 mg twice daily was more effective in maintaining HE remission compared with placebo and was associated with a reduction in HE-related hospitalizations. Recent advances in treatment and preventative therapies may reduce the personal, societal, and economic impact of this disorder.

Toxic epidermal necrolysis associated with rifaximin

PURPOSE

The case of a patient who developed toxic epidermal necrolysis (TEN) after treatment with rifaximin for hepatic encephalopathy is reported.

SUMMARY

A 62-year-old Caucasian woman with a history of alcohol abuse arrived at the emergency room with complaints of abdominal pain and acute onset of jaundice, likely secondary to alcoholic hepatitis. Laboratory tests and multiple imaging studies conducted in the emergency department revealed signs of chronic liver disease and common bile duct dilation with ascites. At admission, she had low concentrations of serum sodium, serum chloride, serum creatinine, and serum albumin and elevated liver function test values. On hospital day 7, the patient developed an altered mental status, which was diagnosed as toxic metabolic encephalopathy, primarily hepatic in origin. The patient was given lactulose 20 g via nasogastric tube every 12 hours and rifaximin 400 mg orally every 8 hours. The patient received only two doses of the rifaximin before it was discontinued. On hospital day 27, oral rifaximin 550 mg twice daily was initiated. After 12 days of rifaximin therapy, the patient developed a diffuse, erythematous, maculopapular, and desquamating cutaneous reaction on her chest, arms, and legs. The suspected diagnosis was determined to be a severe cutaneous adverse drug reaction, possibly TEN. Use of the Naranjo et al. scale revealed that rifaximin was a possible cause of the reaction. Rifaximin was discontinued, and antihistamines and i.v. corticosteroids were initiated. The reaction completely resolved after one week.

CONCLUSION

A 62-year-old woman developed possible TEN after receiving rifaximin to treat hepatic encephalopathy.

A randomized, double-blind, controlled trial comparing rifaximin plus lactulose with lactulose alone in treatment of overt hepatic encephalopathy

OBJECTIVES

Hepatic encephalopathy (HE) is associated with poor prognosis in cirrhosis. Drugs used in the treatment of HE are primarily directed at the reduction of the blood ammonia levels. Rifaximin and lactulose have shown to be effective in HE. We evaluated the efficacy and safety of rifaximin plus lactulose vs. lactulose alone for treatment of overt HE.

METHODS

In this prospective double-blind randomized controlled trial, 120 patients with overt HE were randomized into two groups: (group A lactulose plus rifaximin 1,200 mg/day; n=63) and group B (lactulose (n=57) plus placebo). The primary end point was complete reversal of HE and the secondary end points were mortality and hospital stay.

RESULTS

A total of 120 patients (mean age 39.4±9.6 years; male/female ratio 89:31) were included in the study. 37 (30.8%) patients were in Child-Turcotte-Pugh (CTP) class B and 83 (69.2%) were in CTP class C. Mean CTP score was 9.7±2.8 and the MELD (model for end-stage liver disease) score was 24.6±4.2. At the time of admission, 22 patients (18.3%) had grade 2, 40 (33.3%) had grade 3, and 58 (48.3%) had grade 4 HE. Of the patients, 48 (76%) in group A compared with 29 (50.8%) in group B had complete reversal of HE (P<0.004). There was a significant decrease in mortality after treatment with lactulose plus rifaximin vs. lactulose and placebo (23.8% vs. 49.1%, P<0.05). There were significantly more deaths in group B because of sepsis (group A vs. group B: 7:17, P=0.01), whereas there were no differences because of gastrointestinal bleed (group A vs. group B: 4:4, P=nonsignificant (NS)) and hepatorenal syndrome (group A vs. group B: 4:7, P=NS). Patients in the lactulose plus rifaximin group had shorter hospital stay (5.8±3.4 vs. 8.2±4.6 days, P=0.001).

CONCLUSION

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

Antibiotics for the treatment of hepatic encephalopathy

The treatment of hepatic encephalopathy (HE) is complex and therapeutic regimens vary according to the acuity of presentation and the goals of therapy. Most treatments for HE rely on manipulating the intestinal milieu and therefore antibiotics that act on the gut form a key treatment strategy. Prominent antibiotics studied in HE are neomycin, metronidazole, vancomycin and rifaximin. For the management of the acute episode, all antibiotics have been tested. However the limited numbers studied, adverse effects (neomycin oto- and nephrotoxicity, metronidazole neurotoxicity) and potential for resistance emergence (vancomycin-resistant enterococcus) has limited the use of most antibiotics, apart from rifaximin which has the greatest evidence base. Rifaximin has also demonstrated, in conjunction with lactulose, to prevent overt HE recurrence in a multi-center, randomized trial. Despite its cost in the US, rifaximin may prove cost-saving by preventing hospitalizations for overt HE. In minimal/covert HE, rifaximin is the only systematically studied antibiotic. Rifaximin showed improvement in cognition, inflammation, quality-of-life and driving simulator performance but cost-analysis does not favor its use at the current time. Antibiotics, especially rifaximin, have a definite role in the management across the spectrum of HE.

l-ornithine-l-aspartate for hepatic encephalopathy in patients with cirrhosis: a meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Several randomized, controlled trials that evaluated the effectiveness of l-ornithine-l-aspartate (LOLA) in the treatment of hepatic encephalopathy (HE) have been published recently. The purpose of this study was to update the meta-analysis to reevaluate the safety and efficacy of LOLA on HE in patients with cirrhosis.

METHODS

The following databases were searched from inception to June 2012: Medline, Embase, and the Cochrane Central Register of Controlled Trials (Issue 6). Differences between groups were assessed by the pooled risk ratio (RR) or mean difference (MD). Possible sources of heterogeneity were assessed by sensitivity analyses.

RESULTS

Eight randomized controlled trials with 646 patients were included. When comparing placebo/no-intervention control, LOLA was significantly more effective in the improvement of HE in the total (RR: 1.49, 95% confidence interval [CI]: 1.10 to 2.01), overt HE (RR: 1.33, 95% CI: 1.04 to 1.69), and minimal HE patients (RR: 2.25, 95% CI: 1.33 to 3.82). Furthermore, the reduction of fasting ammonia significantly favored LOLA (post-treatment value, MD: -18.26, 95% CI: -26.96 to -9.56; change, MD: 8.59, 95% CI: 5.22 to 11.96). The tolerance ratio, incidence of adverse events, and mortality were not significantly different between LOLA and the placebo/no-intervention control. LOLA and lactulose demonstrated similar effectiveness in the improvement of HE (RR: 0.88, 95% CI: 0.57 to 1.35).

CONCLUSIONS

LOLA benefits both overt and minimal HE patients in the improvement of HE by reducing the serum ammonia concentration compared with the placebo/no-intervention control. Further, evaluations between LOLA and other effective treatments are needed.

Update on the management of cirrhosis - focus on cost-effective preventative strategies

Cirrhosis is a chronic liver disease stage that encompasses a variety of etiologies resulting in liver damage. This damage may induce secondary complications such as portal hypertension, esophageal variceal bleeding, spontaneous bacterial peritonitis, and hepatic encephalopathy. Screening for and management of these complications incurs substantial health care costs; thus, determining the most economical and beneficial treatment strategies is essential. This article reviews the economic impact of a variety of prophylactic and treatment regimens employed for cirrhosis-related complications. Prophylactic use of β-adrenergic blockers for portal hypertension and variceal bleeding appears to be cost-effective, but the most economical regimen for treatment of initial bleeding is unclear given that cost comparisons of pharmacologic and surgical regimens are lacking. In contrast, prophylaxis for spontaneous bacterial peritonitis cannot be recommended. Standard therapy for spontaneous bacterial peritonitis includes antibiotics, and the overall economic impact of these medications depends largely on their direct cost. However, the potential development of bacterial antibiotic resistance and resulting clinical failure should also be considered. Nonabsorbable disaccharides are standard therapies for hepatic encephalopathy; however, given their questionable efficacy, the nonsystemic antibiotic rifaximin may be a more cost-effective, long-term treatment for hepatic encephalopathy, despite its increased direct cost, because of its demonstrated efficacy and prevention of hospitalization. Further studies evaluating the cost burden of cirrhosis and cirrhosis-related complications, including screening costs, the cost of treatment and maintenance therapy, conveyance to liver transplantation, liver transplantation success, and health-related quality of life after transplantation, are essential for evaluation of the economic burden of hepatic encephalopathy and all cirrhosis-related complications.

Rifaximin versus Nonabsorbable Disaccharides for the Treatment of Hepatic Encephalopathy: A Meta-Analysis

Background. Many studies have found that the antibiotic rifaximin is effective for the treatment of hepatic encephalopathy. However, there is no uniform view on the efficacy and safety of rifaximin. Methods. We performed a meta-analysis through electronic searches to evaluate the efficacy and safety of rifaximin in comparison with nonabsorbable disaccharides. Results. A total of 8 randomized controlled trials including 407 patients were included. The efficacy of rifaximin was equivalent to nonabsorbable disaccharides according to the statistical data (risk ratio (RR): 1.06, 95% CI: 0.94–1.19; P = 0.34). Analysis showed that patients treated with rifaximin had better results in serum ammonia levels (weighted mean difference (WMD): −10.63, 95% CI: −30.63–9.38; P = 0.30), mental status (WMD: −0.32, 95% CI: −0.67–0.03; P = 0.07), asterixis (WMD: −0.12, 95% CI: −0.31–0.08; P = 0.23), electroencephalogram response (WMD: −0.21, 95% CI: −0.34–−0.09; P = 0.0007), and grades of portosystemic encephalopathy (WMD: −2.30, 95% CI: −2.78–−1.82; P < 0.00001), but only the last ones had statistical significance. The safety of rifaximin was better than nonabsorbable disaccharides (RR: 0.19, 95% CI: 0.10–0.34; P < 0.00001). Conclusion. Rifaximin is at least as effective as nonabsorbable disaccharides, maybe better for the treatment of hepatic encephalopathy. And the safety of rifaximin is better.

Efficacy of L-carnitine in reducing hyperammonaemia and improving neuropsychological test performance in patients with hepatic cirrhosis : results of a randomised trial

OBJECTIVES

To determine the efficacy of L-carnitine in reducing hyperammonaemia and improving neuropsychological performance in patients with hepatic cirrhosis and subclinical hepatic encephalopathy (SHE).

DESIGN

Randomised, parallel group, controlled trial.

PATIENTS AND METHODS

The study enrolled 31 patients with hepatic cirrhosis resulting from hepatitis C and/or hepatitis B, alcohol abuse and other causes. Patients randomised to active treatment, received oral L-carnitine 6 g/day in two divided doses for 4 weeks. Diagnosis of SHE was based on psychometric tests (subtests of the Wechsler Adult Intelligence Scale-Revised and the Halstead-Reitan Neuropsychological Test Battery) carried out at beginning and end of study. Serum ammonia levels were measured before treatment and weekly thereafter.

RESULTS

A total of 27 patients completed the study. Sixteen patients received L-carnitine and 11 served as controls (no treatment). L-carnitine caused rapid and significant reductions in ammonia levels, sustained over the 4-week treatment period (mean reductions 60.1 and 1.4 (μmol/L in the treated and control groups, respectively). Normal ammonia levels were attained in 14 of 16 patients receiving L-carnitine. Based on psychometric test results, seven patients (43.7%) in the L-carnitine group and five (45.5%) in the control group had SHE at baseline. L-carnitine treatment for 4 weeks caused a net overall improvement in psychometric test results compared with controls. No clinically significant adverse events were reported and all patients receiving L-carnitine reported subjective improvements in their condition.

CONCLUSIONS

RESULTS of this preliminary study indicate that L-carnitine reduces hyperammonaemia and improves the clinical symptoms of SHE in patients with hepatic cirrhosis.

Rifaximin, but not growth factor 1, reduces brain edema in cirrhotic rats

AIM: To compare rifaximin and insulin-like growth factor (IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.

METHODS: Rats with CCl₄-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups: Cirrhosis; Cirrhosis + IGF-1; Cirrhosis + rifaximin; Controls; Controls + IGF-1; and Controls + rifaximin. An oral glutamine-challenge test was performed, and plasma and cerebral ammonia, glucose, bilirubin, transaminases, endotoxemia, brain water content and ileocecal cultures were measured and liver histology was assessed.

RESULTS: Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups, and improved some liver function parameters (bilirubin, alanine aminotransferase and aspartate aminotransferase). These effects were associated with a significant reduction in cerebral water content. Blood and cerebral ammonia levels, and area-under-the-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals. By contrast, IGF-1 administration failed to improve most alterations observed in cirrhosis.

CONCLUSION: By reducing gut bacterial overgrowth, only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema, alterations associated with hepatic encephalopathy.

Rifaximin vs conventional oral therapy for hepatic encephalopathy: A meta-analysis

AIM: To characterize the efficacy of rifaximin in the management of hepatic encephalopathy (HE) as several randomized controlled studies have shown contradictory results on its effectiveness in comparison to other oral agents.

METHODS: We performed a systematic review and random effects meta-analysis of all eligible trials identified through electronic and manual searches. Twelve randomized controlled trials met the inclusion criteria with a total of 565 patients.

RESULTS: The clinical effectiveness of rifaximin was equivalent to disaccharides or other oral antibiotics [odds ratio (OR) 0.96; 95% CI: 0.94-4.08] but with a better safety profile (OR 0.27; 95% CI: 0.12-0.59). At the completion of treatment protocols, patients receiving rifaximin showed lower serum ammonia levels [weighted mean difference (WMD) = -10.65; 95% CI: -23.4-2.1; P = 0.10], better mental status (WMD = -0.24; 95% CI: -0.57-0.08; P = 0.15) and less asterixis (WMD -0.1; 95% CI -0.26-0.07; P = 0.25) without reaching statistical significance. On the other hand, other psychometric outcomes such as electroencephalographic response and grades of portosystemic encephalopathy were superior in patients treated with rifaximin in comparison to the control group (WMD = 0.21, 95% CI: -0.33-0.09, P = 0.0004; and WMD = -2.33, 95% CI: -2.68-1.98, P = 0.00001, respectively). Subgroup and sensitivity analysis did not show any significant difference in the above findings.

CONCLUSION: Rifaximin appears to be at least as effective as other conventional oral agents for the treatment of HE with a better safety profile.

Treatment guidelines for hepatic encephalopathy

Practice guidelines for hepatic encephalopathy were developed and published in 2001 for overall management in adults. Hepatic encephalopathy is caused by nitrogenous substances from the gastrointestinal tract that adversely affect brain function. Hepatic encephalopathy is a diagnosis of exclusion. The West Haven criteria are recommended for staging the disease. Treatment goals are providing supportive care, identifying and removing precipitating factors, reducing nitrogenous load, and assessing long-term therapy needs. Data from some trials published before 2001 are not included in the guidelines. In addition, since the publication of the guidelines, new data have become available regarding treatment interventions and outcomes. Newer, nonabsorbed agents, such as rifaximin, alone or in conjunction with lactulose, may enhance compliance and adherence with therapy, and provide better treatment outcomes. New updated practice guidelines need to be developed for hepatic encephalopathy, along with treatment algorithms for patients with both minimal hepatic encephalopathy and overt hepatic encephalopathy.

A current review of the diagnostic and treatment strategies of hepatic encephalopathy

Hepatic encephalopathy (HE) is a serious and potentially fatal complication in patients with cirrhotic liver disease. It is a spectrum ranging from minimal hepatic encephalopathy (MHE) without recognizable clinical symptoms or signs, to overt HE with risk of cerebral edema and death. HE results in diminished quality of life and survival. The broad range of neuropsychiatric manifestations reflects the range of pathophysiological mechanisms and impairment in neurotransmission that are purported to cause HE including hyperammonemia, astrocyte swelling, intra-astrocytic glutamine, upregulation of 18-kDa translocator protein (TSPO) (formerly known as peripheral benzodiazepine receptor or PBTR), and manganese. There is a myriad of diagnostic tools including simple bedside clinical assessment, and more complex neuropsychological batteries and neurophysiological tests available today. Current treatment strategies are directed at reducing ammonia, with newer agents showing some early promise. This paper describes the pathophysiology of the disease and summarises current diagnostic and treatment therapies available.

Rifaximin in the treatment of hepatic encephalopathy

Hepatic encephalopathy is a challenging complication in patients with advanced liver disease. It can be defined as a neuropsychiatric syndrome caused by portosystemic venous shunting, ranging from minimal to overt hepatic encephalopathy or coma. Its pathophysiology is still unclear, although increased levels of ammonia play a key role. Diagnosis of hepatic encephalopathy is currently based on specific tests evaluating the neuropsychiatric state of patients and their quality of life; the severity of hepatic encephalopathy is measured by the West Haven criteria. Treatment of hepatic encephalopathy consists of pharmacological and corrective measures, as well as nutritional interventions. Rifaximin received approval for the treatment of hepatic encephalopathy in 2010 because of its few side effects and pharmacological benefits. The aim of this work is to review the use and efficacy of rifaximin both in acute and long-term management of hepatic encephalopathy. Treatment of overt hepatic encephalopathy involves management of the acute episode as well as maintenance of remission in those patients who have previously experienced an episode, in order to improve their quality of life. The positive effect of rifaximin in reducing health care costs is also discussed.

Critical care management of patients with end-stage liver disease

OBJECTIVES

To review the management of complications related to end-stage liver disease in the intensive care unit. The goal of this review is to address topics important to the practicing physician.

DATA SOURCES

We performed an organ system-based PubMed literature review focusing on the diagnosis and treatment of critical complications of end-stage liver disease. DATA SYNTHESIS AND FINDINGS: When available, preferential consideration was given to randomized controlled trials. In the absence of trials, observational and retrospective studies and consensus opinions were included. We present our recommendations for the neurologic, cardiovascular, pulmonary, gastrointestinal, renal, and infectious complications of end-stage liver disease.

CONCLUSIONS

Complications related to end-stage liver disease have significant morbidity and mortality. Management of these complications in the intensive care unit requires awareness and expertise among physicians from a wide variety of fields.

Rifaximin treatment for reduction of risk of overt hepatic encephalopathy recurrence

Hepatic encephalopathy (HE) is a common problem in patients with chronic liver disease and is characterized by diminished mentation and neuromuscular abnormalities. Symptoms range from subtle cognitive changes to coma and death. Gut-derived toxins such as ammonia are thought to play a central role in the pathogenesis of HE. Treatment strategies are directed at increased elimination or reduction of gut-derived ammonia in addition to correction of dynamic conditions that provoke bouts of HE. The standard of care for treatment of acute HE is lactulose, a nonabsorbable disaccharide that is thought to increase elimination and reduce absorption of ammonia. Although lactulose seems to work in the acute setting, the rate of recurrent HE on maintenance lactulose is high. Medications have been sought that reduce the rate of recurrent HE in patients at high risk for HE but none have been identified. Rifaximin is a poorly absorbed antibiotic that is thought to reduce ammonia production by eliminating ammonia-producing colonic bacteria. Many small studies have suggested that rifaximin is effective in treating acute HE and is extremely well tolerated. This led to a randomized, placebo-controlled, multicenter, multinational trial investigating the efficacy of rifaximin over a 6-month period in reducing the risk of recurrent HE in patients at baseline, but with a history of at least two bouts of acute HE in the previous 6 months prior to enrollment. Lactulose could be administered at the discretion of the investigator. A total of 299 patients were randomized to receive rifaximin or placebo; 91% of patients in each group received lactulose. Compared with placebo, patients at high risk for recurrent HE in the rifaximin group had highly statistically significant reductions in bouts of acute HE (58%) and reductions in hospitalizations related to HE (50%) over a 6-month period. The medication was well tolerated with a side-effect profile comparable to placebo. This led to the approval of rifaximin for reduction of risk of recurrent HE by the US Food and Drug Administration in March 2010. It is recommended that patients with a history of recurrent acute HE should be maintained on rifaximin with or without lactulose to reduce the risk of recurrent HE and related hospitalization.

Rifaximin for the treatment of hepatic encephalopathy

BACKGROUND

Previous studies suggest that rifaximin is efficacious in the treatment of hepatic encephalopathy.

OBJECTIVE

To evaluate the efficacy and safety of rifaximin in addition to lactulose in improving hospitalization outcomes in patients with hepatic encephalopathy.

METHODS

Hospital records of patients evaluated for liver transplantation at a single center between January 2006 and May 2008 were reviewed. Hospitalizations for hepatic encephalopathy and other conditions and the incidence of spontaneous bacterial peritonitis and adverse events were analyzed.

RESULTS

Charts of 65 patients who were treated with rifaximin and lactulose were analyzed. Patients received lactulose (20-120 g/d; lactulose phase) before treatment with rifaximin (400- 1200 mg/d; rifaximin phase). During the rifaximin phase, the risk, number, and duration of hospitalizations for hepatic encephalopathy were reduced compared with the lactulose phase. Treatment, age, and Model for End-Stage Liver Disease score were independent predictors of hospitalizations for hepatic encephalopathy (P < .05). The rifaximin phase had fewer hospitalizations than the lactulose phase (36 vs 47, respectively) and a smaller percentage of patients with repeated hospitalizations than the lactulose phase (5% vs 14%, respectively; P = .006) for conditions other than hepatic encephalopathy. A smaller percentage of patients had evidence of spontaneous bacterial peritonitis during the rifaximin phase than the lactulose phase (2% vs 12%, respectively; P = .02). Rifaximin was better tolerated than lactulose.

CONCLUSIONS

Addition of rifaximin to lactulose therapy significantly reduced the risk and duration of hospitalizations for hepatic encephalopathy.

Current and emerging strategies for treating hepatic encephalopathy

Hepatic encephalopathy (HE) is caused by liver impairment and has a multitude of symptoms in affected patients, including change in level of consciousness, intellectual function, and neuromuscular function. Pharmacologic therapy includes use of nonabsorbable disaccharides (lactulose and lactitol), and antibiotics such as neomycin, paromycin, metronidazole, and rifaximin. Probiotics, acarbose, and drugs such as L-carnitine and flumazenil, may also be helpful in treating HE.