Albumin dialysis in cirrhosis with superimposed acute liver injury: a prospective, controlled study

Survival Benefits With Artificial Liver Support System for Acute-on-Chronic Liver Failure: A Time Series-Based Meta-Analysis

The artificial liver support system (ALSS) offers the potential to improve the prognosis of patients with acute-on-chronic liver failure (ACLF). However, the literature has been inconsistent on its survival benefits. We aimed to conduct a time series-based meta-analysis of randomized clinical trials (RCTs) and observational studies which examined differences in mortality in ACLF patients treated with ALSS or not.MEDLINE, EMBASE, OVID, and COCHRANE library database were systemically searched up to December 2014. Quality of included studies was evaluated using the Jadad score. The outcome measure was mortality at different follow-up endpoints. Odds ratios (ORs) and survival curve data were pooled for analysis.Ten studies, 7 RCTs, and 3 controlled cohorts were enrolled, involving a total of 1682 ACLF patients, among whom 842 were treated with ALSS. ALSS was found to reduce the risk of short-term (1-month and 3-month) mortality for patients with ACLF by nearly 30%. Randomized trials and observational studies provided good internal and external validity respectively. The combined Kaplan-Meier curves showed a consistent pattern of findings. Meta-analysis also suggested that ALSS might reduce medium-term (6-month and 1-year) mortality risk by 30% and long-term (3-year) mortality risk by 50% in ACLF patients.ALSS therapy could reduce short-term mortality in patients with ACLF. Meanwhile, its impacts on medium- and long-term survival seem to be promising but remained inconclusive. Clinical utility of this system for survival benefit may be implied.

Continuous molecular adsorbent recirculating system treatment in 69 patients listed for liver transplantation

OBJECTIVE

The molecular adsorbent recirculating system (MARS) is used to purify blood from albumin-bound toxins in patients with liver failure. However, the application of MARS has not demonstrated improved survival in randomized clinical trials and the clinical utility has not been finally established. In our department, the use of MARS is now restricted to the most critically ill patients with acute or acute on chronic liver failure.

MATERIAL AND METHODS

Since 2005, we have treated 69 patients (30 males/39 females with median age of 49 years ranging from 1 months to 70 years) listed for liver transplantation (LT) with MARS. Median model of end-stage liver disease score in patients older than 12 years of age (n = 56) was 33 (interquartile range 26-39). The flow rate was 35-40 mL/kg/h and treatment kits were changed every 8-12 h. The patients were treated for a median of 27 h (range 1-144 h).

RESULTS

Fifty-six patients (81%) were transplanted. Nine died before they could be transplanted, and four patients recovered without transplantation. Forty-six (82%) of the transplanted patients were alive 30 days after transplantation. Ammonium decreased modestly from a median of 148 to 124 µM (p = 0.03) during MARS treatment. We detected worsening of coagulopathy with significant decreases in platelet count and fibrinogen concentrations, and increase in International Normalized Ratio. Phosphate and magnesium decreased significantly during MARS treatment.

CONCLUSION

Continuous MARS therapy may bridge liver failure patients to LT under close observation and treatment of coagulopathy and electrolyte disturbances.

Albumin Dialysis for Liver Failure: A Systematic Review

Albumin dialysis is the best-studied extracorporeal nonbiologic liver support system as a bridge or destination therapy for patients with liver failure awaiting liver transplantation or recovery of liver function. We performed a systematic review to examine the efficacy and safety of 3 albumin dialysis systems (molecular adsorbent recirculating system [MARS], fractionated plasma separation, adsorption and hemodialysis [Prometheus system], and single-pass albumin dialysis) in randomized trials for supportive treatment of liver failure. PubMed, Ovid, EMBASE, Cochrane's Library, and ClinicalTrials.gov were searched. Two authors independently screened citations and extracted data on patient characteristics, quality of reports, efficacy, and safety end points. Ten trials (7 of MARS and 3 of Prometheus) were identified (620 patients). By meta-analysis, albumin dialysis achieved a net decrease in serum total bilirubin level relative to standard medical therapy of 8.0 mg/dL (95% confidence interval [CI], -10.6 to -5.4) but not in serum ammonia or bile acids. Albumin dialysis achieved an improvement in hepatic encephalopathy relative to standard medical therapy with a risk ratio of 1.55 (95% CI, 1.16-2.08) but had no effect survival with a risk ratio of 0.95 (95% CI, 0.84-1.07). Because of inconsistency in the reporting of adverse events, the safety analysis was limited but did not demonstrate major safety concerns. Use of albumin dialysis as supportive treatment for liver failure is successful at removing albumin-bound molecules, such as bilirubin and at improving hepatic encephalopathy. Additional experience is required to guide its optimal use and address safety concerns.

Pattern and profile of chronic liver disease in acute on chronic liver failure

The etiology of the chronic liver disease (CLD) in patients with acute on chronic liver failure (ACLF) may vary from region to region. The major cause of underlying CLD is viral (hepatitis B and C) in the East, while it is alcohol related in the West and in some parts of the Indian subcontinent. Autoimmune liver disease and Wilson's disease are the major underlying etiologies in the pediatric age group. The patients with CLD without cirrhosis should be included when defining ACLF. Non-alcoholic fatty liver disease related chronic liver insult in patients with known risk factors for progressive disease should be taken as a chronic liver disease in the setting of ACLF, whereas fatty liver with normal aminotransferases in low risk patients should not. The patients with CLD and previous decompensation should be excluded. Diagnosis of chronic liver disease in the setting of ACLF is made by history, physical examination and previously available or recent laboratory, endoscopic or radiological investigations. A liver biopsy through the transjugular route may help in cases where the presence of underlying CLD or its cause is not clear. The need of liver biopsy in ACLF should, however, be individualized. Standardization of liver biopsy assessment is essential for a uniform approach to the diagnosis and treatment of CLD and acute insult. Tools to measure liver stiffness may aid in identifying patients with advanced fibrosis. Studies are needed to validate the performance of these tests in the setting of ACLF.

Cytokine level modifications: molecular adsorbent recirculating system versus standard medical therapy

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a systemic inflammatory reaction, which is characterized by a predominantly proinflammatory cytokine profile, causing the transition from stable cirrhosis to ACLF. The aim of the present study was to evaluate the changes in several cytokines associated with inflammatory liver disease and liver regeneration among 15 ACLF patients treated with the Molecular Adsorbent Recirculating System (MARS) compared with 15 patients treated with standard medical therapy (SMT). The subjects showed various disease etiologies but similar values for Model End-stage Liver Disease scores.

METHODS

In the MARS group, 15 (10 male and 5 female) patients were treated with MARS (Gambro). The number of MARS applications was nine; the length of applications was 8 hours. In the SMT group; 15 (10 male and 5 female) patients were treated with SMT. The patients were monitored for 30 days from inclusion with a survival follow-up at 3 months. Statistical results were calculated with SPSS14.0 (SPSS Inc, Chicago, Ill). A P < .07 was considered significant.

RESULTS

In the MARS group, we observed significant changes in the levels of Interleukin (IL)-6, IL-1, IL-10, and tumor necrosis factor (TNF)-alpha in association with improved hepatocyte growth factor. Patient survival at 3 months was 60%. The SMT group showed only a significant change in TNF-alpha (P = .03). Patient survival at 3 months was 30%.

CONCLUSION

The MARS liver support device corrected pathophysiologies of ALF and may be used to enhance spontaneous recovery or as a bridge to transplantation.

Artificial liver support system improves short- and long-term outcomes of patients with HBV-associated acute-on-chronic liver failure: a single-center experience

For patients with acute-on-chronic liver failure (ACLF), artificial liver support system (ALSS) may help prolong lifespan and function as a bridge to liver transplantation (LT), but data on its long-term benefit are lacking. We conducted this prospective, controlled study to determine the efficacy of ALSS and the predictors of mortality in patients with hepatitis B virus (HBV)-associated ACLF.From January 2003 to December 2007, a total of 234 patients with HBV-associated ACLF not eligible for LT were enrolled in our study. They were allocated to receive either plasma exchange centered ALSS plus standard medical therapy (SMT) (ALSS group, n=104) or SMT alone (control group, n=130). All the patients were followed-up for at least 5 years, or until death.At 90 days, the survival rate of ALSS group was higher than that of the control group (62/104 [60%] vs 61/130 [47%], respectively; P<0.05). Median survival was 879 days in the ALSS group (43% survival at 5 years) and 649 days in the control group (31% survival at 5 years, log-rank P<0.05). ALSS was found to be associated with favorable outcome of these patients by both univariate and multivariate analysis. Multivariate Cox regression analysis also revealed that lower serum sodium levels, higher grades of encephalopathy, presence of cirrhosis, hepatorenal syndrome, and higher model for end-stage liver disease scores were independent predictors for both 90-day and 5-year mortality due to ACLF.Our findings suggest that ALSS is safe and may improve the short- and long-term prognosis of patients with HBV-associated ACLF.

Management of chronic hepatitis B in severe liver disease

In the past few decades, chronic hepatitis B (CHB) has evolved from a disease that was untreatable and progressive, to one that can be easily controlled with antiviral therapy. However, patients with severe liver disease still remain difficult to treat despite the availability of highly potent nucleos(t)ide analogs. These include those with underlying cirrhosis, severe flares of CHB, hepatocellular carcinoma (HCC), and for those undergoing liver transplantation. For those with established cirrhosis, antiviral therapy should be considered for all, as unpredictable flares can still occur, which can be fatal for those with advanced chronic liver disease. However, even with effective viral suppression, the development of HCC can still occur. For patients with severe flares of CHB, although the use of antiviral can improve long term outcomes, a significant proportion may still die without liver transplantation. The short term prognosis of these patients is dependent on both the severity of flare and underlying pre-existing liver disease. In patients with decompensated cirrhosis, liver failure secondary to severe flares, or those with HCC, liver transplantation may be curative. After liver transplantation, long term antiviral therapy is required to prevent graft loss from recurrent hepatitis B infection. The use of hepatitis B immune globulin (HBIG) in combination with an oral antiviral agent has been the mainstay of post-transplant antiviral regimen for over a decade. With newer and more potent antiviral agents such as tenofovir and entecavir, use of these agents along with HBIG have demonstrated to be effective in preventing significant recurrence in the long term.

Intensive care unit management of patients with liver failure

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) usually mandate management within an intensive care unit (ICU). Even though the conditions bear some similarities, precipitating causes, and systemic complications management practices differ. Although early identification of ALF and ACLF, improvements in ICU management, and the widespread availability of liver transplantation have improved mortality, optimal management practices have not been defined. This article summarizes current ICU management practices and identifies areas of management that require further study.

Molecular adsorbent recirculating system and bioartificial devices for liver failure

Acute liver failure and acute-on-chronic liver failure remain clinical problems with unacceptable morbidity and mortality. The development of extracorporeal liver support systems that replace the detoxification, synthetic, and regulatory functions of the native liver represent a long-sought potential solution, but all the devices currently available are still far from ideal. In general, artificial (cell-free) and bioartificial liver support devices have shown their ability to decrease some circulating toxins, to ameliorate hepatic encephalopathy and other intermediate variables, and to be relatively safe. Their effects on the survival of patients with ALF or ACLF, however, have not been conclusively shown.

No sustained impact of intermittent extracorporeal liver support on thrombocyte time course in a randomized controlled albumin dialysis trial

Reduction of platelets is a common finding in patients with liver disease and can be aggravated by extracorporeal therapies, e.g. artificial liver support. The impact of extracorporeal albumin dialysis on the time count and time course of platelets in liver failure patients was evaluated in a randomized controlled clinical trial. Mean thrombocyte reduction during a single extracorporeal liver support therapy was -15.1% [95%CI: -17.7; -12.5]. No differences were found between treatments of patients with a more reduced platelet count (<100 GPT/L: -15.6% [-19.5; -11.7%]; n = 43) compared to patients with normal or slightly decreased thrombocytes (-14.6% [-18.3%; -11.0%]; n = 43; P = 0.719). The variation of platelet count within 24 h after onset of extracorporeal therapy treatment was less, albeit significant (-3.5% [-6.3%; -0.7%], P < 0.016). Absolute thrombocyte variability was comparable between both groups (with extracorporeal therapy -5.6 GPT/L [-9.7; -1.4], without extracorporeal therapy -1.3 GPT/L [-7.3; 4.7]; P = 0.243), whereas relative decrease of thrombocytes within a 24-h period of extracorporeal therapy was greater than the changes in patients without extracorporeal therapy (-3.5% [-6.3%; -0.7%] vs. 2.0% [-2.0%; 5.9%]; P = 0.026]. Within a period of two weeks after enrollment, no significant differences of platelet count were observed either between the two groups or in the time course (P(group) = 0.337, P(time) = 0.277). Reduction of platelets during intermittent extracorporeal liver support was less pronounced within a 24-h period as before and after a single treatment and was comparable to variations in the control group without extracorporeal therapy.

Liver dialysis in acute-on-chronic liver failure: current and future perspectives

Patients with acute-on-chronic liver failure (ACLF) are known to have a very high mortality rate as the majority of these patients succumb to multiorgan failure. Liver transplant remains the only option for these patients; however, there are problems with its availability, cost and also the complications and side effects associated with immunosuppression. Unlike advanced decompensated liver disease, there is a potential for hepatic regeneration and recovery in patients with ACLF. A liver support system, cell or non-cell based, logically is likely to provide temporary functional support until the donor liver becomes available or the failing liver survives the onslaught of the acute insult and spontaneously regenerates. Understanding the pathogenesis of liver failure and regeneration is essential to define the needs for a support system. Removal of hepatotoxic metabolites and inhibitors of hepatic regeneration by liver dialysis, a non-cell-based hepatic support, could help to provide a suitable microenvironment and support the failing liver. The current systems, i.e., MARS and Prometheus, have failed to show survival benefits in patients with ACLF based on which newer devices with improved functionality are currently under development. However, larger randomized trials are needed to prove whether these devices can enable restoration of the complex dysregulated immune system and impact organ failure and mortality in these patients.

Liver support strategies: cutting-edge technologies

The treatment of end-stage liver disease and acute liver failure remains a clinically relevant issue. Although orthotopic liver transplantation is a well-established procedure, whole-organ transplantation is invasive and increasingly limited by the unavailability of suitable donor organs. Artificial and bioartificial liver support systems have been developed to provide an alternative to whole organ transplantation, but despite three decades of scientific efforts, the results are still not convincing with respect to clinical outcome. In this Review, conceptual limitations of clinically available liver support therapy systems are discussed. Furthermore, alternative concepts, such as hepatocyte transplantation, and cutting-edge developments in the field of liver support strategies, including the repopulation of decellularized organs and the biofabrication of entirely new organs by printing techniques or induced organogenesis are analysed with respect to clinical relevance. Whereas hepatocyte transplantation shows promising clinical results, at least for the temporary treatment of inborn metabolic diseases, so far data regarding implantation of engineered hepatic tissue have only emerged from preclinical experiments. However, the evolving techniques presented here raise hope for bioengineered liver support therapies in the future.

Development of high-efficiency molecular adsorbent recirculating system: preliminary report

Molecular Adsorbent Recirculating System (MARS) is a liver support system widely employed in the treatment of liver failure. The method is normally well tolerated. To develop a liver support system combining high efficiency and tolerability, we modified the MARS albumin circuit with the insertion of double adsorption units in parallel. Four patients have been treated with this modified method (high-efficiency MARS, HE MARS): two had very high serum bilirubin and two had very high total bile acids. After a single MARS session bilirubin was reduced more with HE MARS than standard MARS (from 27.6 to 52.3% in patient A and from 27.9 to 49.1% in patient B), and bile acid reduction increased from 40 to 59.8% in patient C and from 39.9 to 60% in patient D. The results of this preliminary investigation in only a very small number of patients do support the possibility of developing a liver support system that combines good tolerability and high efficacy.

[Hepatorenal syndrome]

Hepatorenal syndrome is a severe complication of end-stage liver disease. The pathophysiological hallmark is severe renal vasoconstriction, resulting from peripheral and splanchnic vasodilation as well as activation of renal vasoconstrictor molecules, which induce the effective arterial volume reduction and the functional renal failure. The diagnosis of hepatorenal syndrome is currently based on the exclusion of other causes of renal failure (especially prerenal). Spontaneous bacterial peritonitis is one of the triggering factors and should be sought in all patients with severe liver disease and acute renal failure. Quickly treating patients with parental antibiotics and albumin infusion significantly decreases the risk. The combined use of intravenous albumin, splanchnic and peripheral vasoconstrictor and/or renal replacement therapy sometimes enables a delay until liver transplantation (or combined liver-kidney in selected patients). Transplantation is in fact the only way to improve the long-term prognosis.

Extracorporeal liver support

PURPOSE OF REVIEW

The mortality in patients suffering from liver failure decreased in line with medical progress over the past decades. However, it still remains unacceptably high and liver transplantation still provides the only definite treatment for many patients. The goal of extracorporeal liver support systems is to improve the clinical condition of patients waiting for liver transplantation and/or enhance the regeneration of native injured liver. Nonbiological liver support systems with pure detoxification and biological liver support systems with assumed synthesis and metabolism in addition to detoxification are currently under clinical investigation. Since patient survival is the most significant outcome parameter, we focus in this review on prospective randomized trials with survival rate as primary outcome parameter.

RECENT FINDINGS

Although a short-term outcome benefit in patients with acute-on-chronic liver failure was shown in some of these trials, long-term outcome has not been improved significantly with either of the support systems. In spite of more favourable but yet limited data in patients with acute liver failure, it is too early to draw definite conclusions.

SUMMARY

The future development of liver support systems may provide different combinations of new adsorbents, integrated regional citrate anticoagulation and eventual substitution of irreversibly damaged albumin.

Early predictor of mortality due to irreversible posthepatectomy liver failure in patients with hepatocellular carcinoma

BACKGROUND

Although mortality after liver resection has declined, posthepatectomy liver failure (PHLF) remains a major cause of operative mortality. To date there is not consensus on a definition for PHLF. However, there have been many efforts to define PHLF causing operative mortality. In the present study we sought to identify early predictors of death from irreversible PHLF.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 359 patients with hepatocellular carcinoma who underwent liver resection between March 2000 and December 2010. Various biochemical parameters from postoperative days (POD) 1, 3, 5, and 7 were analyzed and compared with the "50-50" criterion.

RESULTS

Operative mortality was 4.7 %. Prothrombin time (PT) <65 % and bilirubin ≥ 38 μmol/L on POD 5 showed the only significant difference as compared with "50-50" criterion. The new combination of bilirubin level and the international normalized ratio showed higher sensitivity, area under the curve, as well as similar accuracy (sensitivity 78.6 vs. 28.6 %; p = 0.002; area under the curve 0.8402 vs. 0.6396; p = 0.00176; accuracy 88.6 vs. 93.4 %; p = 0.090). Multivariate analysis revealed the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 to be the only independent predictive factor of mortality (odds ratio, 82.29; 95 % confidence interval 8.69-779.64; p < 0.001).

CONCLUSIONS

In patients with chronic liver disease who will undergo liver resection the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 may be a more sensitive predictor than the "50-50" criterion of mortality from PHLF. Although it needs to validated by prospective study, this measure may be applied to select patients receiving artificial liver supports or liver transplantation.

Acute liver failure

Untreated acute liver failure (ALF) has a poor outcome and so rapid diagnosis and management is vital if the patient is to survive. ALF has such profound and widespread physiological consequences that whenever possible, patients with ALF should be managed in an intensive care unit. Management is to support the physiology and treat the underlying cause. Advice should be sought from a centre capable of performing liver transplantation. Should recovery seem unlikely, liver transplantation is a viable treatment option in some cases.

The role of molecular adsorbent recirculating system dialysis for extracorporeal liver support in children

The majority of children with acute, acute-on-chronic, and progressive chronic liver failure require liver transplantation. Since organ availability is limited, extracorporeal liver support systems are increasingly applied to bridge the time until transplantation. At present, four different devices are available: the molecular adsorbent recirculating system (MARS), Prometheus dialysis, plasma exchange combined with hemodialysis (PE/HD), and single-pass albumin dialysis (SPAD). Randomized trials in adults have demonstrated efficient toxin removal, improved portal hypertension, hemodynamic stability, and improved hepatic encephalopathy compared with standard medical therapy. None of the liver support systems has yet been evaluated systematically in children. Knowledge of the specific indications and technical features of the different devices is essential if applied in children. MARS combines albumin dialysis with conventional hemodialysis and allows for efficient removal of water and protein-bound toxins without exogenous protein delivery and the associated infectious and allergic risks. It has successfully been applied in children with otherwise intractable cholestatic pruritus and with liver failure. The benefits, however, need to be balanced against the costs and the risk of volume and nitrogen overload if repeated plasma infusion is required. In cases of active bleeding, plasma exchange in combination with hemodialysis should be preferred.

Oroxylin A accelerates liver regeneration in CCl₄-induced acute liver injury mice

Introduction

Based on the previous research that oroxylin A can suppress inflammation, we investigated the hepatoprotective role of oroxylin A against CCl₄-induced liver damage in mice and then studied the possible alteration of the activities of cytokine signaling participating in liver regeneration. Wild type (WT) mice were orally administrated with oroxylin A (60 mg/kg) for 4 days after CCl₄ injection, the anti-inflammatory effects of oroxylin A were assessed directly by hepatic histology and indirectly by measuring serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and Albumin. Proliferating cell nuclear antigen (PCNA) staining was performed to evaluate the role of oroxylin A in promoting hepatocyte proliferation. Serum IL-1β, TNF-α, IL-6 and IL-1Ra levels were measured by enzyme-linked immunosorbent assay (ELISA) and liver HGF, EGF, TNF-α, IL-6, IL-1Ra and IL-1β gene expression was determined by quantitative real-time PCR. The data indicated that the IL-6 and TNF-α mRNA of oroxylin A administered group significantly increased higher than the control within 12 hours after CCl₄ treatment. Meanwhile, oroxylin A significantly enhanced the expression of IL-1Ra at the early phase, which indicated that oroxylin A could facilitate the initiating events in liver regeneration by increasing IL-1Ra which acts as an Acute-Phase Protein (APP). In addition, a lethal CCl₄-induced acute liver failure model offers a survival benefit in oroxylin A treated WT mice. However, oroxylin A could not significantly improve the percent survival of IL-1RI^−/− mice with a lethal CCl₄-induced acute liver failure.

Conclusions

Our study confirmed that oroxylin A could strongly promote liver structural remodeling and functional recovery through IL-1Ra/IL-1RI signaling pathway. All these results support the possibility of oroxylin A being a therapeutic candidate for acute liver injury.

Liver transplantation in acute-on-chronic liver failure patients with high model for end-stage liver disease (MELD) scores: a single center experience of 100 consecutive cases

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a severe clinical condition for which liver transplantation (LT) is the only curative option. However, there are little published data on risk factors and outcomes of LT for ACLF.

METHODS

The objective of this study was to analyze preoperative, intraoperative, postoperative, and overall survival data on 100 consecutive cases with ACLF in order to try to determine for which patients LT are futile.

RESULTS

One hundred consecutive patients with pathology-confirmed ACLF who underwent LT from June 2004 to September 2012 were enrolled. The preoperative data showed that all patients were in a serious condition with a median high model for end-stage liver disease (MELD) score of 32, total bilirubin of 440.20 umol/L, international normalized ratio (INR) of 3.012, and at least one organ dysfunction as assessed by a Sequential Organ Failure Assessment (SOFA) score of ≥9. The patients had either deceased or a living donor LT with an overall mortality of 20%. The 1-, 3-, and 5-year cumulative survival rates were 76.8%, 75.6%, and 74.1%, respectively, and graft 1-, 3-, and 5-y accumulative survival rates were 73.3%, 72.1%, and 70.6%, respectively. However, the area under receiver operating characteristic of SOFA score, MELD score, as well as Child-Pugh score were 0.552, 0.547, and 0.547, respectively.

CONCLUSIONS

Both deceased and living donor LT are effective therapeutic options for patients with ACLF and the short- and long-term survival rates are encouraging. It is important to conduct more prospective and multi-center studies to define preoperatively which patients would benefit from LT.

Artificial and bioartificial liver support systems for acute and acute-on-chronic hepatic failure: A meta-analysis and meta-regression

Artificial and bioartificial liver support systems (LSSs) appear to be safe and effective in the treatment of acute and acute-on-chronic hepatic failure (AHF and AOCHF); however, individually published studies and previous meta-analyses have revealed inconclusive results. The aim of the present meta-analysis was to derive a more precise estimation of the benefits and disadvantages of artificial and bioartificial LSSs for patients with AHF and AOCHF. A literature search was conducted in the PubMed, Embase, Web of Science and Chinese Biomedical (CBM) databases for publications prior to March 1, 2013. Crude relative risks (RRs) or standardized mean differences (SMDs) with 95% confidence intervals (95% CI) were calculated using either the fixed effects or random effects models. Nineteen randomized controlled trials (RCTs) were included, which comprised a total of 566 patients with AHF and 371 patients with AOCHF. The meta-analysis showed that artificial LSS therapy significantly reduced mortality in patients with AOCHF; however, it had no apparent effect on total mortality in patients with AHF. The results also indicated that the use of bioartificial LSSs was correlated with decreased mortality in patients with AHF. A significant reduction in the bridging to liver transplantation was observed in patients with AOCHF following artificial LSS therapy; however, similar results were not observed in patients with AHF. Patients with AHF and those with AOCHF showed significant reductions in total bilirubin levels following artificial LSS therapy. There were no significantly increased risks of hepatic encephalopathy or bleeding in either the patients with AHF or AOCHF following artificial or bioartificial LSS therapies. Univariate and multivariate meta-regression analyses confirmed that none of the factors explained the heterogeneity. The present meta-analysis indicated that artificial LSSs reduce mortality in patients with AOCHF, while the use of bioartificial LSSs was correlated with reduced mortality in patients with AHF.

Liver support systems: will they ever reach prime time?

Liver support systems aim to provide temporary support of liver function while maintaining extra-hepatic function in patients with liver failure. Important advances have been achieved in the design of artificial and bio-artificial devices, but the current systems are far from meeting the ideal. Artificial devices provide detoxification through different dialysis procedures, whereas bio-artificial devices add synthetic functions by incorporating a cellular component into the system. Overall, liver support systems have consistently shown beneficial effects on the pathophysiology of liver failure, especially in acute-on-chronic liver failure. However, these beneficial effects have not been translated into an improvement of survival. Our review discusses the current evidence, paying special attention to the clinical aspects of (bio)-artificial liver support devices.

Extracorporeal detoxification for hepatic failure using molecular adsorbent recirculating system: depurative efficiency and clinical results in a long-term follow-up

Acute liver failure and acute-on-chronic liver failure still show a poor prognosis. The molecular adsorbent recirculating system (MARS) has been extensively used as the most promising detoxifying therapy for patients with these conditions. Sixty-four patients with life-threatening liver failure were selected, and 269 MARS treatments were carried out as a bridge for orthotopic liver transplantation (OLT) or for liver function recovery. All patients were grouped according to the aim of MARS therapy. Group A consisted of 47 patients treated for liver function recovery (median age 59 years, range 23-82). Group B consisted of 11 patients on the waiting list who underwent OLT (median age 47 years, range 32-62). Group C consisted of 6 patients on the waiting list who did not undergo OLT (median age 45.5 years, range 36-54, P = 0.001). MARS depurative efficiency in terms of liver toxins, cytokines, and growth factors was assessed together with the clinical outcome of the patients during a 1-year follow-up. Total bilirubin reduction rate per session (RRs) for each MARS session was 23% (range 17-29); direct bilirubin RRs was 28% (21-35), and indirect bilirubin RRs was 8% (3-21). Ammonia RRs was 34% (12-86). Conjugated cholic acid RRs was 58% (48-61); chenodeoxycholic acid RRs was 34% (18-48). No differences were found between groups. Hepatocyte growth factor (HGF) values on starting MARS were 4.1 ng/mL (1.9-7.9) versus 7.9 ng/mL (3.2-14.1) at MARS end (P < 0.01). Cox regression analysis to determine the risk factors predicting patient outcomes showed that age, male gender, and Sequential Organ Failure Assessment score (but not Model for End-stage Liver Disease score) were factors predicting death, whereas the number of MARS sessions and the ΔHGF proved protective factors. Kaplan-Meier survival analysis was also used; after 12 months, 21.3% of patients in Group A survived, while 90.9% were alive in Group B and 16.7% in Group C (log rank = 0.002). In conclusion, MARS was clinically well tolerated by all patients and significantly reduced hepatic toxins. Better survival rates were linked to an OLT program, but patients' clinical characteristics on starting MARS therapy were the main factors predicting survival. The role of HGF should be evaluated in larger clinical trials.

Extracorporeal albumin dialysis with the molecular adsorbent recirculating system in acute-on-chronic liver failure: the RELIEF trial

Acute-on-chronic liver failure (ACLF) is a frequent cause of death in cirrhosis. Albumin dialysis with the molecular adsorbent recirculating system (MARS) decreases retained substances and improves hemodynamics and hepatic encephalopathy (HE). However, its survival impact is unknown. In all, 189 patients with ACLF were randomized either to MARS (n=95) or to standard therapy (SMT) (n=94). Ten patients (five per group) were excluded due to protocol violations. In addition, 23 patients (MARS: 19; SMT: 4) were excluded from per-protocol (PP) analysis (PP population n=156). Up to 10 6-8-hour MARS sessions were scheduled. The main endpoint was 28-day ITT and PP survival. There were no significant differences at inclusion, although the proportion of patients with Model for Endstage Liver Disease (MELD) score over 20 points and with spontaneous bacterial peritonitis (SBP) as a precipitating event was almost significantly greater in the MARS group. The 28-day survival was similar in the two groups in the ITT and PP populations (60.7% versus 58.9%; 60% versus 59.2% respectively). After adjusting for confounders, a significant beneficial effect of MARS on survival was not observed (odds ratio [OR]: 0.87, 95% confidence interval [CI] 0.44-1.72). MELD score and HE at admission and the increase in serum bilirubin at day 4 were independent predictors of death. At day 4, a greater decrease in serum creatinine (P=0.02) and bilirubin (P=0.001) and a more frequent improvement in HE (from grade II-IV to grade 0-I; 62.5% versus 38.2%; P=0.07) was observed in the MARS group. Severe adverse events were similar.

CONCLUSION

At scheduled doses, a beneficial effect on survival of MARS therapy in patients with ACLF could not be demonstrated. However, MARS has an acceptable safety profile, has significant dialysis effect, and nonsignificantly improves severe HE.

Severe hepatic necrosis of unknown causes following ABO-incompatible liver transplantation

Emergency ABO-incompatible (ABO-I) liver transplantations (LTx) have been performed increasingly to treat severe liver failure. Herein, we report a case of severe hepatic necrosis after ABO-I LTx. A 53-year-old man with blood group O was diagnosed as having severe hepatitis B and acute-on-chronic liver failure, and underwent an emergency liver transplantation implanting a blood-group-B liver from a cardiac-death donor. A routine anti-rejection, anti-infection and anti-virus therapy was given after operation. On post-operative day (POD) 16, the recipient had fever and erythra. Laboratory and radiographic examinations suggested a severe hepatic necrosis of unknown causes. The patient was managed with a 10-d methylprednisolone pulse therapy. He was discharged on POD 35 with stable condition, and no recurrent disease was found during the follow-up.

A preliminary study for constructing a bioartificial liver device with induced pluripotent stem cell-derived hepatocytes

BACKGROUND

Bioartificial liver systems, designed to support patients with liver failure, are composed of bioreactors and functional hepatocytes. Immunological rejection of the embedded hepatocytes by the host immune system is a serious concern that crucially degrades the performance of the device. Induced pluripotent stem (iPS) cells are considered a desirable source for bioartificial liver systems, because patient-derived iPS cells are free from immunological rejection. The purpose of this paper was to test the feasibility of a bioartificial liver system with iPS cell-derived hepatocyte-like cells.

METHODS

Mouse iPS cells were differentiated into hepatocyte-like cells by a multi-step differentiation protocol via embryoid bodies and definitive endoderm. Differentiation of iPS cells was evaluated by morphology, PCR assay, and functional assays. iPS cell-derived hepatocyte-like cells were cultured in a bioreactor module with a pore size of 0.2 μm for 7 days. The amount of albumin secreted into the circulating medium was analyzed by ELISA. Additionally, after a 7-day culture in a bioreactor module, cells were observed by a scanning electron microscope.

RESULTS

At the final stage of the differentiation program, iPS cells changed their morphology to a polygonal shape with two nucleoli and enriched cytoplasmic granules. Transmission electron microscope analysis revealed their polygonal shape, glycogen deposition in the cytoplasm, microvilli on their surfaces, and a duct-like arrangement. PCR analysis showed increased expression of albumin mRNA over the course of the differentiation program. Albumin and urea production was also observed. iPS-Heps culture in bioreactor modules showed the accumulation of albumin in the medium for up to 7 days. Scanning electron microscopy revealed the attachment of cell clusters to the hollow fibers of the module. These results indicated that iPS cells were differentiated into hepatocyte-like cells after culture for 7 days in a bioreactor module with a pore size of 0.2 μm.

CONCLUSION

We consider the combination of a bioreactor module with a 0.2-μm pore membrane and embedded hepatocytes differentiated from iPS cells to be a promising option for bioartificial liver systems. This paper provides the basic concept and preliminary data for an iPS cell-oriented bioartificial liver system.PACS code: 87. Biological and medical physics, 87.85.-d Biomedical engineering, 87.85.Lf Tissue engineering, 87.85.Tu Modeling biomedical systems.

The kidney in pediatric liver transplantation: an updated perspective

CKD continues to detract from the success of improved survival in pediatric liver transplantation, and its presence is likely under recognized. Here we review the literature regarding the prevalence, etiology, and management of renal dysfunction in pediatric liver transplant recipients. Long-term studies suggest the prevalence of CKD to be 25-38% by 5-10 yr post-transplant. While important, sole use of serum creatinine overestimates renal function in this population. Screening for and treatment of persistent proteinuria and hypertension as well as minimization of nephrotoxic insults are the mainstays to delay or prevent CKD progression. Office-based blood pressure measures are less sensitive than ABPM, which is specifically recommended by the American Heart Association for its ability to diagnose masked hypertension in pediatric liver transplant recipients. Long-term risk of CKD is predominantly secondary to CNI toxicity. CNI minimization protocols have shown promise in slowing progression of CKD while maintaining graft function, but large-scale randomized control trials with long-term follow-up are needed.

Long-term therapy of a patient with summerskill-walshe-tygstrup syndrome by applying prometheus® liver dialysis: a case report

Summerskill-Walshe-Tygstrup syndrome is a rare benign chronic liver disease characterized by recurring cholestasis with jaundice and severe pruritus. Due to insufficient conservative treatment, liver dialysis by Prometheus^® was applied to a 45-year-old female patient with resistant pruritus. Initially, other possible liver diseases were excluded and the patient was treated symptomatically since the diagnosis of Summerskill-Walshe-Tygstrup was stated in 1998. As conservative and endoscopic methods progressively failed to relieve the patient's suffering, Prometheus^® liver dialysis was performed regularly since 2006 at 3-month intervals and successfully led to a decrease in the patient's symptoms. Cholestatic liver enzymes and also serum bile acids could be lowered significantly from an average of 22.5 ± 2.7 to 7.3 ± 1.7 µmol/l. Consequently, Prometheus^® liver dialysis may be a beneficial option for patients with benign recurrent intrahepatic cholestasis suffering from therapy-resistant symptoms and may be used as well as other extracorporeal liver support devices which have already been reported to improve cholestatic pruritus.

Management of critically-ill cirrhotic patients

Cirrhotic patients are prone to develop life-threatening complications that require emergency care and ICU admission. They can present specific decompensations related to cirrhosis such as variceal bleeding and hepatorenal syndrome (HRS) or other critical events also observed in the general population such as severe sepsis or septic shock. Clinical management of all these entities requires a specific approach in cirrhosis. Cirrhotic patients have a hyperdynamic circulation with high cardiac output and low systemic vascular resistance in the absence of infection. Circulatory dysfunction increases the susceptibility of critically-ill cirrhotic patients to develop multiple organ failure and attenuates vascular reactivity to vasopressor drugs. HRS, a severe functional renal failure occurring in patients with advanced cirrhosis and ascites, is also secondary to this circulatory dysfunction that leads to an extreme renal vasoconstriction. Moreover, hypotensive cirrhotic patients require a carefully balanced replacement of volemia, since overtransfusion increases portal hypertension and the risk of variceal bleeding and undertransfusion causes tissue hypoperfusion which increases the risk of multiple organ failure. Cirrhotic patients are also at a high risk for development of other bleeding complications and are more susceptible to nosocomial infections. This extreme complexity of critically-ill cirrhotic patients requires a specific medical approach that should be known by general intensivists since it has a negative impact on patient prognosis. This review will focus on the diagnostic approach and treatment strategies currently recommended in the critical care management of patients with cirrhosis.

An Introduction to Extracorporeal Blood Purification in Critical Illness

Critical care nephrology is an emerging sub-specialty with rapid technological advancement and a growing body of dedicated literature in blood purification techniques. Their applications have been extended to improve morbidity and survival in multiple organ dysfunctions. Novel techniques have also allowed us to push the frontiers in transplant medicine, giving high-immunological risk patients a chance at a kidney transplant where this was previously precluded by hyperacute antibody-mediated rejection. We aim to review the myriad extracorporeal blood purification techniques now available for treating various critical illnesses in our clinical practice. Some of these techniques will still require further clinical research to determine the optimal timing and dose in order to achieve significant improvement in clinical outcomes.

Hepatorenal syndrome: the 8th International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group

Introduction

Renal dysfunction is a common complication in patients with end-stage cirrhosis. Since the original publication of the definition and diagnostic criteria for the hepatorenal syndrome (HRS), there have been major advances in our understanding of its pathogenesis. The prognosis of patients with cirrhosis who develop HRS remains poor, with a median survival without liver transplantation of less than six months. However, a number of pharmacological and other therapeutic strategies have now become available which offer the ability to prevent or treat renal dysfunction more effectively in this setting. Accordingly, we sought to review the available evidence, make recommendations and delineate key questions for future studies.

Methods

We undertook a systematic review of the literature using Medline, PubMed and Web of Science, data provided by the Scientific Registry of Transplant Recipients and the bibliographies of key reviews. We determined a list of key questions and convened a two-day consensus conference to develop summary statements via a series of alternating breakout and plenary sessions. In these sessions, we identified supporting evidence and generated recommendations and/or directions for future research.

Results

Of the 30 questions considered, we found inadequate evidence for the majority of questions and our recommendations were mainly based on expert opinion. There was insufficient evidence to grade three questions, but we were able to develop a consensus definition for acute kidney injury in patients with cirrhosis and provide consensus recommendations for future investigations to address key areas of uncertainty.

Conclusions

Despite a paucity of sufficiently powered prospectively randomized trials, we were able to establish an evidence-based appraisal of this field and develop a set of consensus recommendations to standardize care and direct further research for patients with cirrhosis and renal dysfunction.

Artificial liver support devices as treatment option for liver failure

Non-biological artificial liver support (ALS) devices aim to remove albumin-bound and water-soluble toxins arising as a result of liver failure. They do not directly improve the liver synthetic capacity. The currently most used devices combine haemodialysis with albumin dialysis (MARS) or plasma separation and filtration (Prometheus). These devices have been used as a treatment for different types of liver failure: acute liver failure, acute-on-chronic liver failure and primary non- or poor-function after liver transplantation. Overall these devices are found to be safe. The following beneficial effects have been documented: improvement of jaundice, amelioration of haemodynamic instability, reduction of portal hypertension, lowering of intracranial pressure and improvement of hepatic encephalopathy. However, recently multicentre controlled trials failed to show a beneficial effect on transplant-free survival. Therefore the use of these devices at present seems only justified as a bridge to liver transplantation.

Clinical profile and predictors of mortality in patients of acute-on-chronic liver failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is characterised by acute hepatic insult manifesting as jaundice and coagulopathy, complicated within 4 weeks by ascites and/or encephalopathy in patients with previously diagnosed or undiagnosed chronic liver disease. We studied the clinical, biochemical and etiological profiles of ACLF patients investigating variables which could predict mortality.

METHODS

Consecutive ACLF patients were enrolled and given standard intensive care management. They were monitored for predictors of 90-day mortality.

RESULTS

91 patients were included; besides jaundice (median bilirubin 23.1mg/dL) and coagulopathy, acute onset ascites with or without encephalopathy was the presenting symptom in 92%. In all patients a first diagnosis of chronic liver disease was made, mainly due to hepatitis B (37%) or alcohol (34%). Reactivation of chronic hepatitis B and alcoholic hepatitis were the common acute insults. The 90-day mortality was 63%. On multivariate analysis, hepatic encephalopathy, low serum sodium, and high INR were found to be independent baseline predictors of mortality. Amongst all severity scores studied, MELD, SOFA and APACHE-II scores had AUROCs of >0.8 which was significantly higher than that of Child-Turcotte-Pugh.

CONCLUSIONS

ACLF has very high mortality. Hepatic encephalopathy, low serum sodium and high INR predict poor outcome. Mortality can also be predicted by baseline MELD, SOFA or APACHE-II scores.

Use of the molecular adsorbent recirculating system (MARS™) for the management of acute poisoning with or without liver failure

INTRODUCTION

There is an increasing interest in recent developments in bioartificial and non-bioartificial devices, so called extracorporeal liver assist devices, which are now used widely not only to increase drug elimination, but also to enhance the removal of endogenous substances in acute liver failure. Most of the non-bioartificial techniques are based on the principle of albumin dialysis. The objective is to remove albumin-bound substances that could play a role in the pathophysiology of acute liver failure by dialysing blood against an albumin-containing solution across a high flux permeable membrane. The most widely used device is the Molecular Adsorbent Recirculating System (MARS™).

METHODS

The relevant English and French literature was identified through Medline using the terms, 'molecular adsorbent recirculating system', 'MARS', 'acute liver failure', 'acute poisoning', 'intoxication'. This search identified 139 papers of which 48 reported on a toxic cause for the use of MARS™. Of these 48 papers, 39 specified the substance (eighteen different substances were identified); two papers reported on the same group of patients. BIOARTIFICIAL AND NON-BIOARTIFICIAL SYSTEMS: Bioartificial systems based on porcine hepatocytes incorporated in the extracorporeal circuit are no longer in use due to the possibility of porcine retroviral transmission to humans. Historically, experience with such devices was limited to a few cases of paracetamol poisoning. In contrast, an abundant literature exists for the non-bioartificial systems based on albumin dialysis. The MARS™ has been used more widely than other techniques, such as the one using fractionated plasma separation and adsorption (Prometheus™). All the extracorporeal liver assist devices are able to some extent to remove biological substances (ammonia, urea, creatinine, bilirubin, bile acids, amino acids, cytokines, vasoactive agents) but the real impact on the patient's clinical course has still to be determined. Improvement in cardiovascular or neurological dysfunction has been shown both in acute liver failure and acute-on-chronic liver failure but no impact on mortality has been reported. ACUTE POISONING WITH LIVER FAILURE: Randomized controlled trials are very limited in number and patients poisoned by paracetamol or Amanita phalloides are usually included for outcome analysis in larger groups of acute liver failure patients. Initial results look promising but should be confirmed. Beyond its effect in liver failure, MARS™ could also enhance the elimination of the drug or toxin responsible for the failure, as is described with paracetamol. ACUTE POISONING WITHOUT LIVER FAILURE: Extracorporeal liver assist devices have also been used to promote elimination of drugs that are highly protein bound. Data in various case reports confirm a high elimination of phenytoin, theophylline and diltiazem. However, definite conclusions on the toxicokinetic or clinical efficacy cannot be drawn.

CONCLUSIONS

Despite the lack of large multicentre randomized trials on the use of MARS™ in patients with acute liver failure, the literature shows clinical and biological benefit from this technique. In drug or toxin-induced acute liver failure, such as paracetamol or mushroom poisoning, MARS™ has been used extensively, confirming in a non-randomized fashion, the positive effect observed in the larger population of acute liver failure patients. Furthermore, as MARS™ has been shown in experimental studies to remove protein-bound substances, it is potentially a promising treatment for patients with acute poisoning from drugs that have high protein-binding capacity and are metabolized by the liver, especially, if they develop liver failure concomitantly.

Acute liver failure: a life-threatening disease

BACKGROUND

An estimated 200 to 500 patients develop life-threatening acute liver failure (ALF) in Germany each year. Only sparse data are currently available on the epidemiology and causes of this condition and on potential treatments for it. This article summarizes our current knowledge of the causes, clinical course, and treatment of ALF.

METHOD

We selectively reviewed the pertinent current literature on ALF from Germany and abroad.

RESULTS

A shift is currently taking place in Germany with respect to the predominant causes of ALF: The leading cause was formerly acute viral hepatitis, but now more cases of ALF are induced by toxic substances, while there is also a growing incidence of cryptogenic subacute ALF. Precise epidemiological data are still lacking. Scoring -systems for the assessment of ALF should take account of hepatic function, the regenerative capacity of the liver, the extent of existing extrahepatic complications, and the risk that further ones will develop. The mortality from ALF has been reduced through improved specific treatment for certain etiological types of ALF, the introduction of liver transplantation, and progress in intensive care medicine. The optimal treatment of ALF patients requires close collaboration among specialists in all of the involved clinical disciplines, as well as between peripheral hospitals and transplantation centers.

CONCLUSION

Precise epidemiological data on ALF are still lacking in Germany, as are prospective, randomized trials of treatments for it. It is nonetheless clear that progress has been made in its diagnosis and treatment.

Acute liver failure: a life-threatening disease

BACKGROUND

An estimated 200 to 500 patients develop life-threatening acute liver failure (ALF) in Germany each year. Only sparse data are currently available on the epidemiology and causes of this condition and on potential treatments for it. This article summarizes our current knowledge of the causes, clinical course, and treatment of ALF.

METHOD

We selectively reviewed the pertinent current literature on ALF from Germany and abroad.

RESULTS

A shift is currently taking place in Germany with respect to the predominant causes of ALF: The leading cause was formerly acute viral hepatitis, but now more cases of ALF are induced by toxic substances, while there is also a growing incidence of cryptogenic subacute ALF. Precise epidemiological data are still lacking. Scoring -systems for the assessment of ALF should take account of hepatic function, the regenerative capacity of the liver, the extent of existing extrahepatic complications, and the risk that further ones will develop. The mortality from ALF has been reduced through improved specific treatment for certain etiological types of ALF, the introduction of liver transplantation, and progress in intensive care medicine. The optimal treatment of ALF patients requires close collaboration among specialists in all of the involved clinical disciplines, as well as between peripheral hospitals and transplantation centers.

CONCLUSION

Precise epidemiological data on ALF are still lacking in Germany, as are prospective, randomized trials of treatments for it. It is nonetheless clear that progress has been made in its diagnosis and treatment.

Artificial extracorporeal liver support therapy in patients with severe liver failure

Severe liver failure is common and carries a high mortality risk in patients with both acute and acute-on-chronic liver failure. The failing liver constitutes a medical emergency, and in many cases liver transplantation is the only definite treatment. Extracorporeal liver support can be employed as a strategy for bridging to transplantation or recovery. This article focuses on options for artificial (nonbiological) extracorporeal treatment: single-pass albumin dialysis, fractionated plasma separation and adsorption (Prometheus(®)) and the molecular adsorbent recirculatory system. Their different principles, potential advantages and indications are discussed. Despite proven biochemical efficacy, there are little data regarding clinical end points. Thus far, molecular adsorbent recirculatory system therapy in acute and acute-on-chronic liver failure showed no survival benefit compared with standard medical therapy. Prometheus therapy showed reduced mortality in subgroups of higher severity of disease compared with standard medical therapy. Nevertheless, the value of extracorporeal liver support remains to be corroborated by further clinical studies that include the optimal timing, mode, intensity and duration of this treatment.

Acute-on-chronic liver failure: current concepts on definition, pathogenesis, clinical manifestations and potential therapeutic interventions

In recent years, acute-on-chronic liver failure has been recognized as a specific clinical form of liver failure associated with cirrhosis. The syndrome refers to an acute deterioration of liver function and subsequently of other end organs over a period of weeks following a precipitating event in a patient with previously well- or reasonably well-compensated cirrhosis. These precipitating events include either an indirect (e.g., variceal hemorrhage, sepsis) or a direct (e.g., drug-induced) hepatotoxic factor. The short-term mortality for this condition is more than 50%. At present, considerable efforts are ongoing to better characterize the syndrome, to gain further insight into its pathophysiology and to optimize therapy. This article aims to highlight the current concepts of these various aspects.

Acute-on-chronic liver failure: extracorporeal liver assist devices

PURPOSE OF REVIEW

Acute-on-chronic liver failure (ACLF), a syndrome precipitated by acute liver injury in patients with advanced cirrhosis, is associated with multiorgan dysfunction and high rates of mortality. Liver support systems have been developed in an attempt to improve survival of patients with ACLF by providing a bridge until recovery of the native liver function.

RECENT FINDINGS

Nonbiological devices such as molecular adsorbent recirculating system (MARS) and fractionated plasma separation and adsorption (Prometheus) are effective in improving severe hepatic encephalopathy and cholestasis, have good safety and tolerability profiles and are frequently employed in patients with ACLD; however, randomized controlled trials (RCTs) failed to show improvement in survival. Biologic devices that incorporate hepatic cells in bioreactors are also under development. Recent data from pilot studies suggested improvement in survival rates in some groups of patients with ACLF; however, their effect on patient survival in RCT is still unknown.

SUMMARY

Liver support systems are safe and well tolerated when used in management of patients with ACLF. Their use should continue in controlled clinical trials to explore their role in bridging patients to liver transplantation or recovery in well defined patient groups.

Proteomic analysis of polypeptides captured from blood during extracorporeal albumin dialysis in patients with cholestasis and resistant pruritus

Albumin dialysis using the molecular adsorbent recirculating system (MARS) is a new therapeutic approach for liver diseases. To gain insight into the mechanisms involved in albumin dialysis, we analyzed the peptides and proteins absorbed into the MARS strong anion exchange (SAX) cartridges as a result of the treatment of patients with cholestasis and resistant pruritus. Proteins extracted from the SAX MARS cartridges after patient treatment were digested with two enzymes. The resulting peptides were analyzed by multidimensional liquid chromatography coupled to tandem mass spectrometry. We identified over 1,500 peptide sequences corresponding to 144 proteins. In addition to the proteins that are present in control albumin-derived samples, this collection includes 60 proteins that were specific to samples obtained after patient treatment. Five of these proteins (neutrophil defensin 1 [HNP-1], secreted Ly-6/uPAR-related protein 1 [SLURP1], serum amyloid A, fibrinogen alpha chain and pancreatic prohormone) were confirmed to be removed by the dialysis procedure using targeted selected-reaction monitoring MS/MS. Furthermore, capture of HNP-1 and SLURP1 was also validated by Western blot. Interestingly, further analyses of SLURP1 in serum indicated that this protein was 3-fold higher in cholestatic patients than in controls. Proteins captured by MARS share certain structural and biological characteristics, and some of them have important biological functions. Therefore, their removal could be related either to therapeutic or possible adverse effects associated with albumin dialysis.

Critical care of the end-stage liver disease patient awaiting liver transplantation

Patients with end-stage liver disease awaiting liver transplantation frequently require intensive care admission and management due to either complications of liver failure or to intercurrent illness, particularly infection. Mortality in such patients is high and the development of an illness necessitating intensive care unit management can influence transplant candidacy. Specialized support frequently requires hemodynamic support, mechanical ventilation, and renal support. In this review, areas of management of particular importance to patients with end-stage liver disease in the intensive care unit are discussed. These areas are hepatic encephalopathy, infectious diseases, cardiovascular support, mechanical ventilation, renal support and combined transplantation, and decisions regarding delisting. Current knowledge specific to these patients, when available, is discussed, current practice is described, and areas of uncertainty in the evidence are discussed.

Comparison of Molecular Adsorbents Recirculating System (MARS) dialysis with combined plasma exchange and haemodialysis in children with acute liver failure

BACKGROUND

Molecular Adsorbents Recirculating System (MARS) is an extracorporeal liver support system eliminating albumin-bound and water-soluble substances. While it is increasingly applied in patients with acute liver failure (ALF), no comparison with standard dialysis methods has yet been performed.

METHODS

This is an analysis of ten children (0.1-18 years) with ALF, who underwent a total of 22 MARS sessions. Standard adult MARS sets were used in seven (23.5-72 kg) and MARS Mini in three children (2.8-13 kg). In eight children, MARS was alternated with combined plasma exchange (PE) and haemodialysis (HD) treatments. Mean treatment duration was 7.2 (6-10) h for MARS and 5.7 (4.5-6.6) h for PE/HD.

RESULTS

Standard MARS treatment only slightly decreased serum bilirubin (16.3 ± 6.5-13.8 ± 5.9 mg/dL) and ammonia (113 ± 62-99 ± 68 μmol/L) and international normalized ratio (INR) tended to increase (1.5 ± 0.3 and 2 ± 1.1). Mini-MARS did not reduce serum bilirubin (19.7 ± 3-20.5 ± 3.2 mg/dL), ammonia slightly decreased (70 ± 24-56 ± 9 μmol/L) and INR increased (2.5 ± 0.7-2.9 ± 1.1, all P = n.s.). In contrast, PE/HD reduced serum bilirubin (23 ± 8.4-14.7 ± 7 mg/dL), ammonia (120 ± 60-70 ± 40 μmol/L) and INR (2.4 ± 0.8-1.4 ± 0.1, all P < 0.05). Intraindividual comparison showed a slight increase in bilirubin by 2 ± 22% with MARS and a reduction by 37 ± 11% with PE/HD (P < 0.001 versus MARS) and a decrease in ammonia of 18 ± 27 and 39 ± 23% (P < 0.05). INR increased during MARS by 26 ± 41% and decreased with PE/HD by 37 ± 20% (P < 0.01). All treatment sessions were well tolerated. Five children died, including the three children treated with Mini-MARS.

CONCLUSION

Our experience suggests superior efficacy of combined PE/HD as compared to intermittent MARS therapy for treating ALF.

Regional citrate anticoagulation in patients with liver failure supported by a molecular adsorbent recirculating system

OBJECTIVE

Regional citrate anticoagulation has emerged as a promising method in critically ill patients at high risk of bleeding. However, in patients with liver failure, citrate accumulation may lead to acid-base and electrolyte imbalances, notably of calcium. The aim of this study was to evaluate the feasibility and safety of regional citrate anticoagulation during liver support using a molecular adsorbent recirculating system as well as its effects on electrolyte and acid-base balance in patients with liver failure.

DESIGN

Prospective observational study.

SETTING

University hospital.

PATIENTS

Twenty critically ill patients supported by molecular adsorbent recirculating system resulting from liver failure between January 2007 and May 2009.

MEASUREMENTS AND MAIN RESULTS

The median duration of molecular adsorbent recirculating system treatment was 20 hrs (interquartile range, 18-22 hrs). Two of 77 molecular adsorbent recirculating system treatments (2%) were prematurely discontinued as a result of filter clotting and bleeding, respectively. The median citrate infusion rate, necessary to maintain the postfilter ionized calcium between 0.2 and 0.4 mmol/L, was 3.1 mmol/L (interquartile range, 2.3-4 mmol/L) blood flow. The median calcium chloride substitution rate was 0.9 mmol/L (0.3-1.7 mmol/L) dialysate. Total serum calcium remained stable during molecular adsorbent recirculating system treatments. There was a statistically significant increase of the ratio of total calcium to systemic ionized calcium (2.04 ± 0.32 mmol/L to 2.17 ± 0.35; p = .01), which reflected citrate accumulation resulting from liver failure. Under close monitoring, no clinically relevant electrolytes or acid-base disorders were observed.

CONCLUSIONS

Our results suggest that regional citrate anticoagulation is a safe and feasible method to maintain adequate circuit lifespan without increasing the risk of hemorrhagic complications while maintaining a normal acid-base as well as electrolyte balance in patients with liver failure supported by molecular adsorbent recirculating system.