Treatment of resistant pruritus from cholestasis with albumin dialysis: combined analysis of patients from three centers

Efficacy and safety of odevixibat in patients with Alagille syndrome (ASSERT): a phase 3, double-blind, randomised, placebo-controlled trial

BACKGROUND

In patients with Alagille syndrome, cholestasis-associated clinical features can include high serum bile acids and severe pruritus that can necessitate liver transplantation. We aimed to evaluate the efficacy and safety of the ileal bile acid transporter inhibitor odevixibat versus placebo in patients with Alagille syndrome.

METHODS

The ASSERT study was a phase 3, double-blind, randomised, placebo-controlled trial that enrolled patients at 21 medical centres or hospitals in ten countries (Belgium, France, Germany, Italy, Malaysia, the Netherlands, Poland, Türkiye, the UK, and the USA). Eligible patients had a genetically confirmed diagnosis of Alagille syndrome, a history of significant pruritus, and elevated serum bile acids. Patients were randomly assigned (2:1) to receive oral odevixibat 120 μg/kg per day or placebo for 24 weeks (in a block size of six and stratified by age: <10 years and ≥10 years to <18 years) via a web-based system. Patients, clinicians, study staff, and people analysing the data were masked to treatment allocation. The primary efficacy endpoint was change in caregiver-reported scratching score (on the PRUCISION instrument; range 0-4) from baseline to weeks 21-24. The prespecified key secondary efficacy endpoint was change in serum bile acid concentration from baseline to the average of weeks 20 and 24. Outcomes were analysed in patients who received at least one dose of study drug (the full analysis set for efficacy outcomes and the safety analysis set for safety outcomes). This trial is registered on ClinicalTrials.gov (NCT04674761) and EudraCT (2020-004011-28), and is completed.

FINDINGS

Between Feb 26, 2021, and Sept 9, 2022, 52 patients were randomly assigned to receive odevixibat (n=35) or placebo (n=17), all of whom were included in the analysis sets. The median age was 5·5 years (IQR 3·2 to 8·9). 27 (52%) of 52 patients were male and 25 (48%) were female. The mean scratching score was elevated at baseline in both groups (2·8 [SD 0·5] for odevixibat vs 3·0 [0·6] for placebo). Mean scratching scores at weeks 21-24 were 1·1 (0·9) for odevixibat and 2·2 (1·0) for placebo, representing a least-squares (LS) mean change of -1·7 (95% CI -2·0 to -1·3) for odevixibat and -0·8 (-1·3 to -0·3) for placebo, which was significantly greater for odevixibat than for placebo (difference in LS mean change from baseline -0·9 [95% CI -1·4 to -0·3]; p=0·0024). Odevixibat also resulted in significantly greater reductions in mean serum bile acids from baseline versus placebo (237 μmol/L [SD 115] with odevixibat vs 246 μmol/L [121] with placebo) to the average of weeks 20 and 24 (149 μmol/L [102] vs 271 μmol/L [167]; LS mean change -90 μmol/L [95% CI -133 to -48] with odevixibat vs 22 μmol/L [-35 to 80] with placebo; difference in LS mean change -113 μmol/L [95% CI -179 to -47]; p=0·0012). The most common treatment-emergent adverse events were diarrhoea (ten [29%] of 35 patients in the odevixibat group vs one [6%] of 17 in the placebo group) and pyrexia (eight [23%] vs four [24%]). Seven patients had serious treatment-emergent adverse events during the treatment period: five (14%) in the odevixibat group and two (12%) in the placebo group. No patients discontinued treatment and there were no deaths.

INTERPRETATION

Odevixibat could be an efficacious non-surgical intervention to improve pruritus, reduce serum bile acids, and enhance the standard of care in patients with Alagille syndrome. Longer-term safety and efficacy data of odevixibat in this population are awaited from the ongoing, open-label ASSERT-EXT study.

FUNDING

Albireo Pharma, an Ipsen company.

Systematic review: efficacy of therapies for cholestatic pruritus

Background

Pruritus is a symptom of several cholestatic liver diseases (CLDs) that can impair health-related quality of life (HRQoL). Despite evidence-based guideline therapy, managing cholestatic pruritus (CP) remains challenging, thus making the need for newer, more effective therapeutic agents more evident.

Objective

Our study evaluated the efficacy of existing CP therapies.

Design

Systematic review.

Data sources

From inception until March 2023, we conducted a comprehensive search of MEDLINE, Cochrane, EMBASE, Scopus, ClinicalTrial.gov, and other sources, including pharmaceutical webpages and conference proceedings published in English that reported on CP interventions.

Methods

Two reviewers independently conducted screening and full-text review of articles with extraction conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The methodological quality of studies included in our qualitative synthesis was assessed by using the Cochrane ROBINS-I and ROBINS-II tools for interventional studies and the National Heart, Lung, and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. The primary outcome assessed in our systematic review was the severity of CP after therapy.

Results

Of 3293 screened articles, 92 studies were eligible for inclusion in the qualitative synthesis. Some patients' HRQoL improved with evidence-based standard therapy. Others, particularly those with severe and refractory CP, often required conversion to or addition of experimental noninvasive (e.g., ondansetron) or extracorporeal liver support to alleviate CP. In addition, studies investigating a newer class drug, the ileal bile acid transporter inhibitor (IBATi), demonstrate its effectiveness in reducing serum bile acid and alleviating CP with sustained improvement noted in patients with the inherited childhood cholestatic disorders - progressive familial intrahepatic cholestasis and Alagille syndrome.

Conclusion

Our findings consolidate data on the efficacy of guideline-based approaches and newer therapies for CP. While the initial findings are promising, additional clinical trials will be needed to determine the full extent of IBATi's efficacy and potential use in treating other common CLDs. These results provide a foundation for future research and highlight the need for continued investigation into the management and treatment of CLDs.

Elevated bile acids are associated with left ventricular structural changes in biliary atresia

BACKGROUND

In children with biliary atresia (BA), pathologic structural changes within the heart, which define cirrhotic cardiomyopathy, are associated with adverse perioperative outcomes. Despite their clinical relevance, little is known about the pathogenesis and triggers of pathologic remodeling. Bile acid excess causes cardiomyopathy in experimental cirrhosis, but its role in BA is poorly understood.

METHODS

Echocardiographic parameters of left ventricular (LV) geometry [LV mass (LVM), LVM indexed to height, left atrial volume indexed to BSA (LAVI), and LV internal diameter (LVID)] were correlated with circulating serum bile acid concentrations in 40 children (52% female) with BA listed for transplantation. A receiver-operating characteristic curve was generated to determine optimal threshold values of bile acids to detect pathologic changes in LV geometry using Youden index. Paraffin-embedded human heart tissue was separately analyzed by immunohistochemistry for the presence of bile acid-sensing Takeda G-protein-coupled membrane receptor type 5.

RESULTS

In the cohort, 52% (21/40) of children had abnormal LV geometry; the optimal bile acid concentration to detect this abnormality with 70% sensitivity and 64% specificity was 152 µmol/L (C-statistics=0.68). Children with bile acid concentrations >152 µmol/L had ∼8-fold increased odds of detecting abnormalities in LVM, LVM index, left atrial volume index, and LV internal diameter. Serum bile acids positively correlated with LVM, LVM index, and LV internal diameter. Separately, Takeda G-protein-coupled membrane receptor type 5 protein was detected in myocardial vasculature and cardiomyocytes on immunohistochemistry.

CONCLUSION

This association highlights the unique role of bile acids as one of the targetable potential triggers for myocardial structural changes in BA.

Artificial liver support in patients with liver failure: a modified DELPHI consensus of international experts

The present narrative review on albumin dialysis provides evidence-based and expert opinion guidelines for clinicians caring for adult patients with different types of liver failure. The review was prepared by an expert panel of 13 members with liver and ntensive care expertise in extracorporeal liver support therapies for the management of patients with liver failure. The coordinating committee developed the questions according to their importance in the management of patients with liver failure. For each indication, experts conducted a comprehensive review of the literature aiming to identify the best available evidence and assessed the quality of evidence based on the literature and their experience. Summary statements and expert's recommendations covered all indications of albumin dialysis therapy in patients with liver failure, timing and intensity of treatment, efficacy, technical issues related to the device and safety. The panel supports the data from the literature that albumin dialysis showed a beneficial effect on hepatic encephalopathy, refractory pruritus, renal function, reduction of cholestasis and jaundice. However, the trials lacked to show a clear beneficial effect on overall survival. A short-term survival benefit at 15 and 21 days respectively in acute and acute-on-chronic liver failure has been reported in recent studies. The technique should be limited to patients with a transplant project, to centers experienced in the management of advanced liver disease. The use of extracorporeal albumin dialysis could be beneficial in selected patients with advanced liver diseases listed for transplant or with a transplant project. Waiting future large randomized controlled trials, this panel experts' statements may help careful patient selection and better treatment modalities.

Adverse events, short- and long-term outcomes of extra corporeal liver therapy in the intensive care unit: 16 years experience with MARS® in a single center

Background

Molecular Adsorbent Recirculating System (MARS®) is a non-biological artificial liver device. The benefit risk ratio between uncertain clinical effects and potential adverse events remains difficult to assess. We sought to describe adverse events related to MARS® therapy as well as biological and clinical effects.

Methods

All intensive care unit (ICU) admissions to whom MARS® therapy was prescribed from March 2005 to August 2021 were consecutively and prospectively included. The main endpoint was the incidence of adverse events related to MARS® therapy. Secondary endpoints were the biological and clinical effects of MARS® therapy.

Results

We reported 180 admissions treated with MARS® therapy. Among the 180 admissions, 56 (31.1%) were for acute-on-chronic liver failure, 32 (17.8%) for acute liver failure, 28 (15.5%) for post-surgery liver failure, 52 (28.9%) for pruritus and 12 (6.7%) for drug intoxication. At least one adverse event occurred in 95 (52.8%) admissions. Thrombocytopenia was the most frequent adverse event which was recorded in 55 admissions (30.6%). Overall, platelets count was 131 (± 95) × 10⁹/L before and 106 (± 72) × 10⁹/L after MARS® therapy (p < .001). After MARS® therapy, total bilirubin was significantly decreased in all groups (p < 0.05). Hepatic encephalopathy significantly improved in both the acute-on-chronic and in the acute liver failure group (p = 0.01). In the pruritus group, pruritus intensity score was significantly decreased after MARS® therapy (p < 0.01).

Conclusion

In this large cohort of patients treated with MARS® therapy we report frequent adverse events. Thrombocytopenia was the most frequent adverse event. In all applications significant clinical and biological improvements were shown with MARS® therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04165-z.

Efficacy of Treatments for Cholestatic Pruritus: A Systemic Review and Meta-analysis

Cholestatic itch is a disabling symptom that may be secondary to liver or biliary diseases. Management of cholestatic pruritus is complex. A systematic review and meta-analysis on the efficacy of treatments for cholestatic pruritus were performed. PubMed and Cochrane Library were searched using the algorithm “(hepatitis OR cholestatic OR liver) AND (pruritus OR itch) AND (management OR treatment OR treatments)” for 1975–2019. Of the 2,264 articles identified, 93 were included in a systematic review and 15 in a meta-analysis (studies evaluating pruritus with a visual analogue scale). Some treatments act by reducing levels of pruritogens in the enterohepatic cycle, others modify the metabolism or secretion of these pruritogens, or act on pruritus pathways. A further possible treatment is albumin dialysis. However, due to many heterogeneities in the reviewed studies it is difficult to identify and recommend an optimum treatment. Only 15 studies were included in the meta-analysis, due to the small number of randomized studies using a visual analogue scale.

Safety considerations for the management of cholestatic itch

Introduction: Pruritus is adisabling symptom common to cholestatic liver disorders. Its pathophysiology has not been completely elucidated and although multiple mediators have been identified, only lysophosphatidic acid (LPA) and its synthetizing enzyme autotaxin (ATX) appear to consistently correlate with symptom intensity. This review aims to summarize the most relevant safety and efficacy data regarding both standard and new medications utilized to treat pruritus in cholestatic liver disease.Areas covered: International societies like the AASLD and EASL recommend astepwise approach for the management of cholestatic itch. However, therapeutic response is variable. Cholestyramine is considered first-line, followed by rifampicin, naltrexone and sertraline. When used appropriately, these medications have afavorable adverse events profile with most side effects related to drug class and not to the underlying etiology of liver disease.Expert opinion: Although conventional therapies seem to be effective in aproportion of patients, asizable number of cases remain refractory and require the utilization of experimental treatments. Multiple potential targets, especially in the ATX-LPA axis have yet to be pharmacologically explored, with ongoing translational and clinical research. Novel drugs are currently being developed for the management of cholestatic itching with promising results and afavorable safety profile.

Cholestasis-Associated Pruritus and Its Pruritogens

Pruritus is a debilitating symptom of various cholestatic disorders, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and inherited progressive familial intrahepatic cholestasis (PFIC). The molecular mechanisms leading to cholestasis-associated pruritus are still unresolved and the involved pruritogens are indecisive. As a consequence of pruritus, patients suffer from sleep deprivation, loss of daytime concentration, auto-mutilation and sometimes even suicidal ideations. Current guideline-approved therapy of cholestasis-associated pruritus includes stepwise administration of several medications, which may alleviate complaints in some, but not all affected patients. Therefore, also experimental therapeutic approaches are required to improve patients' quality of life. This article reviews the current state of research on pruritogens and their receptors, and shortly discusses the most recent experimental therapies.

Similarities, Differences, and Potential Synergies in the Mechanism of Action of Albumin Dialysis Using the MARS Albumin Dialysis Device and the CytoSorb Hemoperfusion Device in the Treatment of Liver Failure

INTRODUCTION

Liver failure is characterized by compromised hepatic detoxification, protein synthesis, and metabolic derangements leading to an accumulation of a broad spectrum of water-soluble and lipophilic toxins as well as immune system mediators. Exploring complex detoxification mechanisms to therapeutically target those components, this article will focus on similarities, differences, and potential synergies in the mechanism of albumin dialysis and hemoperfusion.

METHODS

An in vitro two-compartment model for the comparison of liver support techniques was used to compare MARS albumin dialysis modified with novel charcoal adsorbents to CytoSorb hemoperfusion with added hemodialysis for effects on marker molecule removal.

RESULTS

MARS and CytoSorb performed similar in the removal of water-soluble toxins. Ammonia removal was increased using CytoSorb. CytoSorb lead to a statistically significant reduction of albumin-bound toxins, total bilirubin and subfractions. Bile acid removal was comparable. MARS demonstrated no removal of cytokines interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α), whereas CytoSorb allowed for near complete removal. Notably, CytoSorb displayed 50% of lipophilic substance and cytokine removal during the first hour of treatment.

CONCLUSION

Compared to MARS, CytoSorb hemoperfusion leads to an initially fast removal of cytokines, TNF-α and IL-6, as well as reduction of albumin-bound toxins such as indirect bilirubin and bile acids in our model. The initial removal is also associated with removal of albumin.

MARS: Should I Use It?

Severe liver failure, including acute liver failure and acute-on-chronic liver failure, is associated with high mortality, and many patients die despite aggressive medical therapy. While liver transplantation is a viable treatment option for liver failure patients, a large proportion of these patients die given the shortage in the liver donation and the severity of illness, leading to death while waiting for a liver transplant. Extracorporeal liver support devices, including molecular adsorbent recirculating system (MARS), have been developed as bridge to transplantation (bridge for patients who are decompensating while waiting for liver transplantation) and bridge to recovery (for whom recovery is deemed reasonable). In addition to its uses in acute liver failure and acute-on-chronic liver failure, the MARS system has also been applied in various clinical settings, such as drug overdosing and poisoning and intractable cholestatic pruritus refractory to pharmacological treatment. This review aims to discuss the controversies, potential benefits, practicalities, and disadvantages of using MARS in clinical practice.

Nasobiliary drainage prior to surgical biliary diversion in progressive familial intrahepatic cholestasis type II

Progressive familial intrahepatic cholestasis (PFIC) can cause intense pruritus that is refractory to medical therapy. Surgical biliary diversion techniques, including partial internal biliary diversion (PIBD), have been developed over the years to relieve pruritus without requiring liver transplantation. No clinical or genetic features can currently predict postoperative pruritus response. We present three PFIC type 2 (PIFC 2) patients who underwent transient endoscopic nasobiliary drainage (NBD) prior to PIBD surgery. Two patients repeatedly responded to NBD and presented with complete pruritus resolution after subsequent PIBD. NBD failed technically in the third patient, and PIBD was partially successful. Mild post-endoscopic biological pancreatitis occurred in 2/6 NBD procedures and resolved spontaneously. The only adverse effect observed within 7 years post-PIBD was very mild transient osmotic diarrhea.Conclusion: Our limited data suggest that NBD is a safe and effective way to predict pruritus response before performing permanent biliary diversion surgery in PFIC patients. What is Known: • Surgical biliary diversion techniques have been developed to relieve intractable pruritus in progressive familial intrahepatic cholestasis (PFIC). • No clinical or genetic features can currently predict pruritus response to surgery. What is New: • Our data suggest that nasobiliary drainage could be a safe and effective tool to predict pruritus response to biliary diversion and avoid unnecessary surgery in PFIC patients.

Review article: pathophysiology and management of primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC), an immune-mediated disease characterised by destruction of intrahepatic bile ducts, results in progressive damage to the biliary tree, cholestasis and ultimately advanced liver disease. In the last decade, advances in practice have improved clinical care, driven novel therapeutic options and improved risk stratification tools.

AIMS

To provide an overview of the disease characteristics of PBC and review a patient-centred management approach for the clinical team caring for those with PBC.

METHODS

We reviewed the current literature and guidelines on PBC with a focus on management and therapies.

RESULTS

A confident diagnosis of PBC is usually made based on serum liver tests and immune serology. Management of PBC should focus on three main 'process' pillars: (a) treat and risk-stratify through use of biochemical and prognostic criteria; (b) manage concurrent symptoms and other associated diseases; and (c) stage disease, monitor progression and prevent complications. With ongoing complexities in management, including a newly licensed therapy (obeticholic acid) and alternative non-licensed treatments and ongoing clinical trials, discussion with PBC expert centres is encouraged.

CONCLUSIONS

PBC is a dynamic disease wherein current treatment goals have become appropriately ambitious. Goals of care should prioritise prevention of end-stage liver disease and amelioration of patient symptom burden for all.

Outcome of patients treated with molecular adsorbent recirculating system albumin dialysis: A national multicenter study

Background and Aim

The molecular adsorbent recirculating system (MARS) is the most widely used device to treat liver failure. Nevertheless, data from widespread real‐life use are lacking.

Methods

This was a retrospective multicenter study conducted in all French adult care centers that used MARS between 2004 and 2009. The primary objective was to evaluate patient survival according to the liver disease and listing status. Factors associated with mortality were the secondary objectives.

Results

A total of 383 patients underwent 393 MARS treatments. The main indications were acute liver failure (ALF, 32.6%), and severe cholestasis (total bilirubin >340 μmol/L) (37.2%), hepatic encephalopathy (23.7%), and/or acute kidney injury–hepatorenal syndrome (22.9%) most often among patients with chronic liver disease. At the time of treatment, 34.4% of the patients were listed. Overall, the hospital survival rate was 49% (95% CI: 44–54%) and ranged from 25% to 81% depending on the diagnosis of the liver disease. In listed patients versus those not listed, the 1‐year survival rate was markedly better in the setting of nonbiliary cirrhosis (59% vs 15%), early graft nonfunction (80% vs 0%), and late graft dysfunction (72% vs 0%) (all P < 0.001). Among nonbiliary cirrhotic patients, hospital mortality was associated with the severity of liver disease (HE and severe cholestasis) and not being listed for transplant. In ALF, paracetamol etiology and ≥3 MARS sessions were associated with better transplant‐free survival.

Conclusion

Our study suggests that MARS should be mainly used as a bridge to liver transplantation. Survival was correlated with being listed for most etiologies and with the intensity of treatment in ALF.

Clinical effectiveness of MARS treatment - multidirectional analysis of positive clinical response to treatment

Aim of the study

Liver failure is a life-threatening condition which often requires intensive care treatment. It is essential to quickly determine whether there are indications for extracorporeal liver support systems for the patient. The aims of the study were: to assess effectiveness of molecular adsorbent recirculating system (MARS) therapy based on selected clinical criteria, to analyze the moment of clinical response and to create a patient’s profile, who will benefit clinically from the treatment.

Material and methods

The analysis encompassed medical histories of 65 patients treated with MARS. Effectiveness of treatment was evaluated based on selected clinical parameters. Statistical analysis was performed based on medical data gathered.

Results

There were 158 cycles of MARS performed, with effectiveness documented in 57 cycles (36.6%). The first MARS session was effective in 43.1% of patients. They also more often responded to the second cycle (63.6% vs. 15.4%). A significant part of the analysis was devoted to create a profile of the patient in whom positive response can be expected. A low MELD score and low baseline white blood cells (WBC) level are statistically significant factors in multivariate analysis of selected features of positive clinical response to treatment.

Conclusions

MARS therapy is an effective form of treatment in a properly selected group of patients with liver failure. The first MARS session is the most effective one. It is also a good prognostic factor for further clinical response to treatment. Multifactorial analysis of positive clinical response to treatment enables to create a patient’s profile based on the lower baseline MELD score and WBC.

Cholestatic pruritus: Emerging mechanisms and therapeutics

Patients suffering from cholestasis often report experiencing a debilitating, unrelenting itch. In contrast to conditions, such as urticaria, in which histamine primarily drives itch (pruritus), cholestatic pruritus is multifactorial and more difficult to treat. Existing therapies are not always effective and have undesirable adverse effect profiles. Here, we conducted a systematic literature review to evaluate conventional treatment strategy, current pathophysiologic understanding, and the role of new therapies in the context of cholestatic pruritus. We discuss novel findings implicating bile acids, lysophosphatidic acid, and bilirubin as potential important mediators of cholestatic itch. New therapies that aim to remove or modulate pruritogens have been supported in observational cohort studies and randomized controlled trials. Although these new therapies show promise, further research is needed to confirm the pathophysiology of cholestatic pruritus so that targeted therapy can be developed.

Lysophosphatidic acid activates satellite glia cells and Schwann cells

Pruritus is a common and disabling symptom in patients with hepatobiliary disorders, particularly in those with cholestatic features. Serum levels of lysophosphatidic acid (LPA) and its forming enzyme autotaxin were increased in patients suffering from hepatic pruritus, correlated with itch severity and response to treatment. Here we show that in a culture of dorsal root ganglia LPA 18:1 surprisingly activated a large fraction of satellite glia cells, and responses to LPA 18:1 correlated inversely with responses to neuronal expressed transient receptor potential channels. LPA 18:1 caused only a marginal activation of heterologously expressed TRPV1, and responses in dorsal root ganglion cultures from TRPV1-deficient mice were similar to controls. LPA 18:1 desensitized subsequent responsiveness to chloroquine and TGR5 agonist INT-777. The LPA 18:1-induced increase in cytoplasmatic calcium stems from the endoplasmatic reticulum. LPA receptor expression in dorsal root ganglia and Schwann cells, LPAR1 immunohistochemistry, and pharmacological results indicate a signaling pathway through LPA receptor 1. Peripheral rat Schwann cells, which are of glial lineage as the satellite glia cells, were also responsive to LPA 18:1. Summarizing, LPA 18:1 primarily activates rather glial cells than neurons, which may subsequently modulate neuronal responsiveness and sensory sensations such as itch and pain.

Primary biliary cholangitis

Primary cholangitis (cirrhosis) is a chronic cholestatic disease with an unquestionable female predominance. It is characterised by inflammation of the small and medium size bile ducts, and can eventually progress to cirrhosis. Most patients remain asymptomatic and are diagnosed by the casual finding of an anicteric biochemical cholestasis with increased alkaline phosphatase. The pathogenesis is unknown and of presumed autoimmune origin in genetic susceptible subjects. M2-type antimitochondrial antibodies, and specific antinuclear antibodies (gp210 and Sp100) are typical and specific of the disease. The positivity of these antibodies and a biochemical cholestasis are sufficient for diagnosis, without the need for liver biopsy. Ursodeoxycholic acid is the specific treatment with an excellent response in more than 60% of patients. When this optimal response is not observed, it can be combined with new agents, but those that have shown to be effective are those that improve cholestasis such as fibrates and obeticholic acid.

Understanding and Treating Pruritus in Primary Biliary Cholangitis

Pruritus is a common symptom with primary biliary cholangitis. Research has focused on refining understanding of the neurohumoral pathways involved in transduction of pruritus from peripheral cutaneous receptors to the central nervous system, and identifying modulating drugs. Current treatments have variable efficacy and safety. Because of the deleterious effects on quality of life or debilitation, many patients necessitate individualized therapeutic approaches; clinicians may need to consider invasive treatment options. This article highlights various therapeutic interventions, from general measures to invasive strategies, and novel agents under investigation, providing clinicians with the management tricks of the trade.

Symptoms of PBC - Pathophysiology and management

Primary biliary cholangitis is a chronic cholestatic liver disease characterised by progressive bile duct damage and, ultimately, biliary cirrhosis. Though up to fifty percent of the patients can be asymptomatic at presentation, symptoms when present are frequently debilitating with significant impact on quality of life and functional status. Characteristic symptoms include pruritus, fatigue and an increasingly recognised mild cognitive impairment. With the exception of pruritus, the "classic" cholestatic symptom, therapeutic options to treat PBC related symptoms are currently limited leaving patients with often significant residual problems. Symptoms can frequently contribute to depression and social isolation further compounding the quality of life impairment. There is need to better understand the current therapeutic options available in order to optimise their use, and to explore newer avenues to understand the pathophysiology of the symptom-generating processed in PBC in order to develop new therapies.

Targeting Albumin Binding Function as a Therapy Goal in Liver Failure: Development of a Novel Adsorbent for Albumin Dialysis

Liver failure results in impaired hepatic detoxification combined with diminished albumin synthesis and is associated with secondary organ failure. The accumulation of liver toxins has shown to saturate albumin binding sites. This was previously demonstrated by an in vitro test for albumin binding capacity (ABiC) that has shown to inversely correlate with the established MELD (Model for End-Stage Liver Disease) score. In this study, we introduced a new adsorbent material for albumin dialysis treatments that improves albumin binding capacity. The new charcoal adsorbent was developed by an evolutionary test schedule. Batch testing of charcoals was performed as steady-state experiments. The charcoal reflecting the highest increase in albumin binding capacity was then introduced to kinetic models: Perfusion tests were designed to evaluate adsorption capacity and kinetics for liver failure marker toxins. A dynamic recirculation model for liver failure was used for upscaling and comparison against conventional MARS adsorbents as the gold standard in an albumin dialysis setting. Batch tests revealed that powdered activated Hepalbin charcoal displayed the highest ABiC score. Hepalbin charcoal also demonstrated higher adsorptive capacity and kinetics for liver failure marker toxins as determined by perfusion tests. These findings translated to tests of upscaled adsorbents in a dynamic model for liver failure: upscaled Hepalbin adsorbent removes bile acids, direct bilirubin and indirect bilirubin significantly better than MARS adsorbents and significantly increases ABiC. The novel adsorbent Hepalbin offers a significant improvement over both MARS adsorbents concerning liver failure marker toxin removal and ABiC improvement.

Novel strategies and therapeutic options for the management of primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease. It has a varied course of progression ranging from being completely asymptomatic to aggressive disease leading to cirrhosis and resulting in liver transplantation. In addition, symptoms can be debilitating and can have a major impact on quality of life. For decades, there was only one anti-cholestatic agent available to target this disease and that was only effective in around half of patients, with little or no effect on symptoms. With increasing understanding of the pathogenic mechanisms of PBC and potential targets for drug treatment, pharmaceutical companies have shown a greater interest in this rare disease. A large number of novel therapeutic molecules have been developed and are currently being evaluated. In this review article all the novel molecules in use and in trials targeting cholestasis and symptoms in PBC are discussed.

Assessment of the Visual Analogue Score in the Evaluation of the Pruritus of Cholestasis

Background and Aims: A visual analogue score (VAS), based on application of a visual analogue scale, has been widely used to assess pruritus in clinical studies of patients with cholestatic liver disease. A VAS is a numerical score of the severity of the perception of pruritus, and, hence, is inherently subjective. The objective of this study was to assess the reliability of a VAS as an index of pruritus in cholestatic patients. Methods: In 8 patients with chronic pruritus due to primary biliary cholangitis, values for a VAS of pruritus were compared with corresponding measurements of scratching activity, which were generated by a monitoring system specifically designed to quantitate this activity. The relationship between individual values for the VAS and corresponding values for scratching activity during a specific interval immediately preceding the recording of the VAS was examined by determining the Spearman's rank correlation coefficient. Results: The mean Spearman's rank correlation coefficient between individual values for the VAS and corresponding mean values for scratching activity was 0.072; the range of these coefficients was -0.04 to 0.26. A VAS of pruritus is an unreliable index of scratching activity, and, hence, of the pathophysiological process responsible for the pruritus of cholestasis. Conclusions: It is concluded that the use of a VAS as a primary quantitative endpoint in trials of the efficacy of potential therapies for the pruritus of cholestasis may be inappropriate.

Removal of bile acids by extracorporeal therapies: an in vitro study

INTRODUCTION

Bile acids (BAs) accumulating in the circulation in patients with liver failure are considered to be responsible for pruritus, which strongly impairs quality of life of the affected patients. The aim of this study was the in vitro characterization of different BAs regarding their removability with high-flux dialysis as well as with different adsorbents, and the evaluation of their binding to plasma proteins.

METHODS

Dialysis experiments were conducted in pediatric circuits with human plasma. For the adsorption studies, batch tests using 10% adsorbent in spiked human plasma were carried out. The binding of BAs to plasma compounds was determined by centrifugation of spiked plasma through spin columns. Sieving coefficients were determined using an albumin filter and a high-flux dialyzer.

RESULTS

With high-flux dialysis, only hydrophilic BAs such as glycocholic and taurocholic acid could be removed efficiently, while all tested BAs were removed by adsorption.

CONCLUSIONS

In conclusion, the hydrophilicity of BAs plays a major role in their removability using extracorporeal approaches. Adsorption-based systems offer particular advantages for the removal of hydrophobic BAs.

EASL Clinical Practice Guidelines: The diagnosis and management of patients with primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic inflammatory autoimmune cholestatic liver disease, which when untreated will culminate in end-stage biliary cirrhosis. Diagnosis is usually based on the presence of serum liver tests indicative of a cholestatic hepatitis in association with circulating antimitochondrial antibodies. Patient presentation and course can be diverse and risk stratification is important to ensure all patients receive a personalised approach to their care. The goals of treatment and management are the prevention of end-stage liver disease, and the amelioration of associated symptoms. Pharmacologic approaches in practice, to reduce the impact of the progressive nature of disease, currently include licensed therapies (ursodeoxycholic acid and obeticholic acid) and off-label therapies (fibric acid derivatives, budesonide). These clinical practice guidelines summarise the evidence for the importance of a structured, life-long and individualised, approach to the care of patients with PBC, providing a framework to help clinicians diagnose and effectively manage patients.

Management of Pruritus in Primary Biliary Cholangitis: A Narrative Review

Primary biliary cholangitis is an autoimmune condition characterized by destruction of intrahepatic bile ducts. It causes debilitating symptoms that dramatically affect the patient's quality of life. Pruritus affects 60% to 70% of individuals with primary biliary cholangitis and leads to sleep disturbances, fatigue, depression, and suicidal ideation. A complete search was performed with studies from PubMed, EMBASE, Web of Science, Cochrane database, Countway Library, and CINAHL with specific search terms. This narrative review was prepared after a comprehensive literature review. Treating patients with cholestatic pruritus is challenging and may have a profound impact on quality of life. The standard of therapy for primary biliary cholangitis, ursodeoxycholic acid, does not have a beneficial effect in cholestatic pruritus. Patients often do not respond to conventional therapies such as cholestyramine, rifampicin, opioid antagonists, and sertraline. These therapies lack long-term efficacy and have side effects. Patients who have not responded to these initial treatments can be considered for experimental therapies or clinical trials. This review outlines the current and emerging treatment modalities for patients with primary biliary cholangitis who have pruritus.

Extracorporeal Liver Support Systems in Paediatric Liver Failure

Extracorporeal liver support systems (ELSS), encompassing artificial and bioartificial devices, have been used for decades, with the aim of supporting patients with acute liver failure and acute-on chronic liver failure, as a bridge to recovery (acute liver failure only) or liver transplantation, in an era of organ donation shortage. Although biochemical efficacy has been consistently demonstrated by these devices, translation into clinical and survival benefits has been unclear, due to study limitations and lack of reliable prognostic scoring in liver failure. Consequently, extracorporeal devices are not widely accepted as routine therapy in adult liver failure. Recent large multicentre trials using artificial liver systems have not revealed beneficial outcomes associated with albumin dialysis but plasma exchange practices have shown some potential. In paediatric liver failure, data on extracorporeal systems is scarce, comprising few reports on albumin dialysis (namely, Molecular Adsorbent Recirculating System; MARS) and plasma exchange. When extrapolating data from adult studies differences in disease presentation, aetiology, prognosis and the suitability, and safety of such devices in children must be considered. The aim of this review is to critically appraise current practices of extracorporeal liver support systems to help determine efficacy in paediatric liver failure.

Recent advances in the management of pruritus in chronic liver diseases

Pruritus is a symptom found in patients with chronic liver diseases, especially cholestatic liver diseases such as primary biliary cholangitis. This symptom impairs patient quality of life by disturbing sleep and may lead to consideration of liver transplantation. Mechanisms implicated in pruritus have been associated with the peripheral and central nervous systems, leading to the development of various therapeutic options. Little evidence for the efficacy of most of these treatments is currently available, indicating a need for further investigations.

Molecular adsorbent recirculating system (MARS) in acute liver injury and graft dysfunction: Results from a case-control study

Background

The primary therapeutic goals in the treatment of liver injury are to support liver regeneration or bridge the gap to liver transplantation (LT). Molecular adsorbent recirculating system (MARS) therapy has shown beneficial effects for specific symptoms of liver failure; however, general survival advantages have not yet been demonstrated.

Aim

We studied the effects of MARS therapy compared to standard medical treatment (SMT) in two patient cohorts: in patients with an acute liver injury and in those with graft dysfunction (GD).

Methods

We report on our experience over a 6.5-year period with 73 patients treated with SMT or with SMT and MARS (MARS group). In total, 53 patients suffered from acute liver injury in their native liver without a preexisting liver disease (SMT: n = 31, MARS: n = 22), and 20 patients showed a severe GD after LT (SMT: n = 10, MARS: n = 10).

Results

The entire cohort was predominantly characterized by hemodynamically and respiratorily stable patients with a low hepatic encephalopathy (HE) grade and a model of end-stage liver disease (MELD) score of 20.57 (MARS) or 22.51 (SMT, p = 0.555). Within the MARS group, the median number of extracorporeal therapy sessions was four (range = 3–5 sessions). Independent of the underlying etiology, MARS improved the patients’ bilirubin values in the short term compared to SMT alone. In patients with acute liver injury, this response was sustained even after the end of MARS therapy. By contrast, the majority of patients with GD and an initial response to MARS therapy experienced worsened hyperbilirubinemia. No differences in 28-day mortality were observed with respect to acute liver injury (MARS 5.3% (95% CI: 0–15.3); SMT 3.3% (95% CI: 0–9.8), p = 0.754) or GD (MARS 20.0% (95% CI: 0–44.7), SMT 11.1% (95% CI: 0–31.7), p = 0.478).

Conclusions

Although it did not improve 28-day mortality, MARS therapy improved the short-term response in patients with acute liver injury as well as in those with GD. In cases of acute hepatic injury, the use of MARS therapy resulted in the sustained stabilization of liver function and improved liver regeneration. A short-term response to MARS may predict the future course of the disease.

A systematic approach to the management of cholestatic pruritus in primary biliary cirrhosis

Pruritus (itch) is an important symptom of primary biliary cirrhosis (PBC), an archetypal cholestatic liver disease. Cholestatic pruritus can be a debilitating symptom causing significant deterioration in patients' quality of life. Effective management of pruritus in PBC involves awareness among clinicians to adequately assess its severity, and treatment with specific drug therapies in line with current practice guidelines. In PBC, antipruritic drugs are not universally effective and/or have significant side effects, and despite best efforts with various combinations of drugs, some patients remain significantly symptomatic, eventually opting for invasive or experimental treatments. Therefore, there is a clear unmet need for better alternative treatments for patients with refractory or intractable cholestatic pruritus. Recent advances in the understanding of pathogenesis of cholestatic pruritus and bile acid physiology have raised hopes for novel therapies, some of which are currently under trial. In this review, we aim to provide a practical guide to the management of this important and complex problem, discussing current knowledge and recent advances in the pathogenesis, summarise the evidence base for available therapeutic approaches and update potential novel future therapies for the management of pruritus in PBC.

Autotaxin, Pruritus and Primary Biliary Cholangitis (PBC)

Autotaxin (ATX) is a 125-kD type II ectonucleotide pyrophosphatase/phosphodiesterase (ENPP2 or NPP2) originally discovered as an unknown "autocrine motility factor" in human melanoma cells. In addition to its pyrophosphatase/phosphodiesterase activities ATX has lysophospholipase D (lysoPLD) activity, catalyzing the conversion of lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA). ATX is the only ENPP family member with lysoPLD activity and it produces most of the LPA in circulation. In support of this, ATX heterozygous mice have 50% of normal LPA plasma levels. The ATX-LPA signaling axis plays an important role in both normal physiology and disease pathogenesis and recently has been linked to pruritus in chronic cholestatic liver diseases, including primary biliary cholangitis (PBC). Several lines of evidence have suggested that a circulating puritogen is responsible, but the identification of the molecule has yet to be definitively identified. In contrast, plasma ATX activity is strongly associated with pruritus in PBC, suggesting a targetable molecule for treatment. We review herein the biochemistry of ATX and the rationale for its role in pruritus.

Extracorporeal support for patients with acute and acute on chronic liver failure

The number of patients developing liver failure; acute on chronic liver failure and acute liver failure continues to increase, along with the demand for donor livers for transplantation. As such there is a clinical need to develop effective extracorporeal devices to support patients with acute liver failure or acute-on-chronic liver failure to allow time for hepatocyte regeneration, and so avoiding the need for liver transplantation, or to bridge the patient to liver transplantation, and also potentially to provide symptomatic relief for patients with cirrhosis not suitable for transplantation. Currently devices can be divided into those designed to remove toxins, including plasma exchange, high permeability dialyzers and adsorption columns or membranes, coupled with replacement of plasma proteins; albumin dialysis systems; and bioartificial devices which may provide some of the biological functions of the liver. In the future we expect combinations of these devices in clinical practice, due to the developments in bioartificial scaffolds.

Hepatic Failure

The progression of liver disease can cause several physiologic derangements that may precipitate hepatic failure and require admission to an intensive care unit. The underlying pathology may be acute, acute-on chronic, or chronic in nature. Liver failure may manifest with a variety of clinical signs and symptoms that need prompt attention. The compromised synthetic and metabolic activity of the failing liver affects all organ systems, from neurologic to integumentary. Supportive care and specific therapies should be instituted in order to improve outcome and minimize time of recovery.

In this chapter we will discuss the definition, clinical manifestations, workup, and management of acute and chronic liver failure and the general principles of treatment of these patients. Management of liver failure secondary to certain common etiologies will also be presented. Finally, liver transplantation and alternative therapies will also be discussed.

The safety and efficacy of nasobiliary drainage in the treatment of refractory cholestatic pruritus: a multicentre European study

BACKGROUND

Pruritus is a common symptom associated with cholestatic liver diseases. To date only small single centre case series have suggested efficacy of nasobiliary drainage in relieving cholestatic pruritus.

AIM

To perform a multicentre study to evaluate the safety and efficacy of nasobiliary drainage in cholestatic pruritus.

METHODS

This was a retrospective study of all patients treated with nasobiliary drainage for refractory cholestatic pruritus between 2006 and 2015 at five European centres. Pruritus was quantified using a visual analogue scale (VAS) and liver enzymes, serum bilirubin and total serum bile salts (TBS) were measured before (pre-NBD) and after nasobiliary drainage (post-NBD). We analysed the duration of treatment response and associated complications.

RESULTS

In total, 27 patients (59% females) underwent 29 nasobiliary drainage procedures. The median duration of NBD was 7 days. NBD decreased pruritus in 89.6% of cases (VAS from 10.0 to 0.3, P < 0.0001). The median percentage decline in pruritus VAS was 94% and 33% of patients were free of pruritus within 24 h of starting drainage. The duration of treatment response was independent of duration of drainage (P = 0.12) and bile output. Significant improvements were seen in the median levels of serum alkaline phosphatase (P = 0.001) and serum bilirubin (P = 0.03) but not in serum TBS (P = 0.07). Mild post-endoscopic retrograde cholangiopancreatography pancreatitis (31%) was the most frequent complication.

CONCLUSIONS

Nasobiliary drainage is effective in relieving cholestatic pruritus in most patients and has favourable effect on biomarkers of cholestasis. Nasobiliary drainage may be associated with high risk of adverse events, especially pancreatitis. Prospective studies are needed to confirm our findings.

Safety and efficacy of long-term nasobiliary drainage to treat intractable pruritus in cholestatic liver disease

INTRODUCTION

Cholestasis related pruritus, secondary to intrahepatic and/or extrahepatic biliary obstruction is a common manifestation in chronic liver disease. Pruritus is difficult to treat, and results are often suboptimal. A stepwise medical approach is usually employed, followed by a trial molecular adsorbents recirculation system in medication resistant cases. Pruritus resulting in reduced quality of life is a variant syndrome eligible for liver transplantation in the setting of preserved synthetic function.

AIM

This case series describes the use of long-term (LT) nasobiliary drainage (NBD) in three patients with intractable pruritus. This case series tests the hypothesis that LT-NBD could be successfully used to alleviate cholestasis related pruritus, and prevent or delay the need for liver transplantation.

METHOD

LT-NBD was carried out in three female patients (mean age 43 years) with intractable pruritus secondary to primary biliary cirrhosis (PBC) (n=2), and benign recurrent intrahepatic cholestasis (n=1). NBD was carried out through the endoscopic placement of a 6 French Cook Medical nasobiliary catheter into the common bile duct.

RESULTS

Symptomatic relief of pruritus was described by all three cases within 24 h of NBD placement. LT-NBD was stopped in the patient with benign recurrent intrahepatic cholestasis after 8 weeks due to complete resolution of pruritus. In one patient with PBC, LT-NBD was undertaken over 12 months, with complete resolution of pruritus. In the second patient with PBC, LT-NBD was carried out over 14 months, with complete resolution of pruritus.

DISCUSSION

This case series supports the efficacy of LT-NBD in the treatment of intractable pruritus. We propose that NBD offers an accessible modality for the treatment of intractable pruritus in liver disease, potentially avoiding the need for liver transplantation.

Primary biliary cirrhosis: Pathophysiology, clinical presentation and therapy

Primary biliary cirrhosis (PBC) is an autoimmune, slowly progressive, cholestatic, liver disease characterized by a triad of chronic cholestasis, circulating anti-mitochondrial antibodies (AMA), and characteristic liver biopsy findings of nonsuppurative destructive cholangitis and interlobular bile duct destruction. About 10% of PBC patients, however, lack AMA. A variant, called PBC-autoimmune hepatitis (AIH) overlap, is characterized by the above findings of PBC together with findings of elevated serum alanine aminotransferase, elevated serum immunoglobulin G, and circulating anti-smooth muscle antibodies, with liver biopsy demonstrating periportal or periseptal, lymphocytic, piecemeal necrosis. PBC is hypothesized to be related to environmental exposure in genetically vulnerable individuals. It typically occurs in middle-aged females. Prominent clinical features include fatigue, pruritis, jaundice, xanthomas, osteoporosis, and dyslipidemia. The Mayo Risk score is the most widely used and best prognostic system. Ursodeoxycholic acid is the primary therapy. It works partly by reducing the concentration and injury from relatively toxic bile acids. PBC-AIH overlap syndrome is treated with ursodeoxycholic acid and corticosteroids, especially budesonide. Obeticholic acid and fibrate are promising new, but incompletely tested, therapies. Liver transplantation is the definitive therapy for advanced disease, with about 70% 10-year survival after transplantation. Management of pruritis includes local skin care, dermatologist referral, avoiding potential pruritogens, cholestyramine, and possibly opioid antagonists, sertraline, or rifaximin. Management of osteoporosis includes life-style modifications, administration of calcium and vitamin D, and alendronate. Statins are relatively safe to treat the osteopenia associated with PBC. Associated Sjogren’s syndrome is treated by artificial tears, cyclosporine ophthalmic emulsion to stimulate tear production; and saliva substitutes, cholinergic agents, and scrupulous oral and dental care. Complications of cirrhosis from advanced PBC include esophageal varices, ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, and hepatoma formation.

Management of pruritus in chronic liver disease

Background. There continues to be uncertainty on the ideal treatment of pruritus in chronic liver disease. The aim of this study was to gather the latest information on the evidence-based management of pruritus in chronic liver disease. Methodology. A literature search for pruritus in chronic liver disease was conducted using Pubmed and Embase database systems using the MeSH terms “pruritus,” “chronic liver disease,” “cholestatic liver disease,” and “treatment.” Results. The current understanding of the pathophysiology of pruritus is described in addition to detailing research into contemporary treatment options of the condition. These medical treatments range from bile salts, rifampicin, and opioid receptor antagonists to antihistamines. Conclusion. The burden of pruritus in liver disease patients persists and, although it is a common symptom, it can be difficult to manage. In recent years there has been greater study into the etiology and treatment of the condition. Nonetheless, pruritus remains poorly understood and many patients continue to suffer, reiterating the need for further research to improve our understanding of the etiology and treatment for the condition.

Jaundice associated pruritis: A review of pathophysiology and treatment

To review the underlying pathophysiology and currently available treatments for pruritis associated with jaundice. English language literature was reviewed using MEDLINE, PubMed, EMBASE and clinicaltrials.gov for papers and trails addressing the pathophysiology and potential treatments for pruritis associated with jaundice. Recent advances in the understanding of the peripheral anatomy of itch transmission have defined a histamine stimulated pathway and a cowhage stimulated pathway with sensation conveyed centrally via the contralateral spinothalamic tract. Centrally, cowhage and histamine stimulated neurons terminate widely within the thalamus and sensorimotor cortex. The causative factors for itch in jaundice have not been clarified although endogenous opioids, serotonin, steroid and lysophosphatidic acid all play a role. Current guidelines for the treatment of itching in jaundice recommend initial management with biliary drainage where possible and medical management with ursodeoxycholic acid, followed by cholestyramine, rifampicin, naltrexone and sertraline. Other than biliary drainage no single treatment has proved universally effective. Pruritis associated with jaundice is a common but poorly understood condition for which biliary drainage is the most effective therapy. Pharmacological therapy has advanced but remains variably effective.

Unmet clinical need in autoimmune liver diseases

Despite recent advances in understanding and treatment, there remain significant areas of unmet clinical need in each of the autoimmune liver diseases (AILDs). The evolving research landscape and emerging large patient cohorts are creating unique opportunities to translate science into new therapies and care pathways, with the potential to significantly improve the lives of AILD patients. However, the areas of unmet need represent real challenges, which need to be addressed, if this vision is to be realised. This review describes the areas of unmet need in AILD in adults relating to diagnostic and prognostic assessment, primary therapy, symptom management, trial design and delivery, and structured care delivery, with the aim of focusing future research prioritisation.

Treatment of pruritus with Prometheus dialysis and absorption system in a patient with benign recurrent intrahepatic cholestasis

Benign recurrent intrahepatic cholestasis (BRIC) is an autosomal recessive liver disorder characterized by recurrent episodes of jaundice and itching. Episodes of cholestasis last variously from 1 week to several months, may start at any age and usually resolve spontaneously. No effective treatment has been found as yet. We report a case of genetically proven BRIC in a male patient who developed three episodes of pruritus and jaundice at the age of 14, 16 and 19 years. During the third episode, he did not respond to pharmacological medical therapy, and fractionated plasma separation and absorption (FPSA, Prometheus) was performed to manage intractable pruritus. The treatment immediately alleviated pruritus, lowered serum bilirubin concentration and induced sustained remission in the 5-year follow up. FPSA seems to be a safe and effective way of treatment for BRIC in patients with severe pruritus and prolonged jaundice.

Impact of molecular adsorbent recirculating system therapy on tacrolimus elimination: a case report

BACKGROUND

We report a unique case which quantifies the effect of molecular adsorbent recirculating system (MARS [Gambro, Sweden]) therapy on blood concentrations of tacrolimus in a patient treated for refractory pruritus associated with recurrent hepatitis C of the liver allograft. Tacrolimus is a low-molecular-weight, highly protein-bound drug with the potential to be removed during MARS therapy.

CASE REPORT

Results of therapeutic drug monitoring revealed extracorporeal tacrolimus elimination accounted for only 0.3% of total drug removal during the session.

CONCLUSIONS

Although no explanation can be offered as to why MARS contributed so little to overall tacrolimus elimination, the data clearly show minimal impact of MARS on tacrolimus blood level.

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.

Update on primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) remains one of the most challenging conditions of clinical hepatology. There has been a steady growth in research to overcome this fact and the present review aims at summarizing the most recently published literature. The main emphasis will be put on the link of recent pathogenetic insights to clinical characteristics and patient management. With regard to pathogenesis, there is no consensus yet as to whether immune mediated injury or factors related to bile acid physiology are the most important. It also remains to be clarified whether PSC is a mixed bag of various secondary etiologies yet to be defined, or a disease entity predominantly represented by sclerosing cholangitis in the context of inflammatory bowel disease. Most important, there is no available medical therapy with proven influence on clinical end points, and timing of liver transplantation and patient follow-up are challenging due to the unpredictable and high risk of cholangiocarcinoma.

Management of cholestatic pruritus in paediatric patients with alagille syndrome: the King's College Hospital experience

OBJECTIVES

The aims of the study were to perform a retrospective observational review of the present management and outcome of cholestatic pruritus in children with Alagille syndrome (AGS) at King's College Hospital and to use results to inform appropriate guidelines.

METHODS

A retrospective review of 62 patients diagnosed as having AGS from January 1995 to November 2010 treated at King's College Hospital was performed. The departmental database of the Paediatric Liver Centre was searched to identify all patients and the clinical records were then analysed.

RESULTS

Fifty-one (82.3%) patients experienced pruritus and 50 (80.6%) received antipruritic medication. Ursodeoxycholic acid was the most prescribed drug (n = 40). Other drugs prescribed were rifampicin (n = 39), cholestyramine (n = 18), naltrexone (n = 14), alimemazine (n = 13), nonsedating antihistamine agents (n = 7), ondansetron (n = 5), and phenobarbitone (n = 1). Albumin dialysis using the molecular adsorbent recirculation system was used in 1 patient. Sixteen patients (25.8%) were listed for liver transplantation, and 11 had undergone transplantation by November 2010. Patient survival was high at 95.2%. Pruritus resolved permanently in 39.2% (n = 20) of patients. Fifty-five percent (n = 11) of such patients had undergone liver transplantation. Pruritus was controlled by medication in 41.2% (n = 21). Itching remained a significant problem, affecting quality of life in 19.6% of patients (n = 10).

CONCLUSIONS

The management of cholestatic pruritus in AGS is difficult and often suboptimal. Pruritus may remain intractable even with combination medical treatment, and at this stage, surgery or liver transplantation is indicated. At our centre, pruritus was successfully treated in 80.4% of patients with medical and surgical management.

Advances in pathogenesis and treatment of pruritus

The pathogenesis of itch during cholestasis is largely unknown and treatment options are limited. Lysophosphatidate, female steroid hormones, and endogenous opioids are among the agents discussed as potential pruritogens in cholestasis. The itch-alleviating action of guideline-based therapeutic interventions with anion exchanger resins, rifampicin, opioid antagonists, and serotonin reuptake inhibitors are studied to unravel the molecular pathogenesis of itch. Still, a considerable part of the patients is in need of alternative experimental therapeutic approaches (eg, UV-B phototherapy, extracorporeal albumin dialysis, nasobiliary drainage), providing additional information about the enigmatic pathophysiology of cholestatic pruritus.

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.