Intensive care management of acute-on-chronic liver failure.

Acute-on-chronic liver failure (ACLF) is a clinical syndrome defined by an acute deterioration of the liver function associated with extrahepatic organ failures requiring intensive care support and associated with a high short-term mortality. ACLF has emerged as a major cause of mortality in patients with cirrhosis and chronic liver disease. ACLF has a unique pathophysiology in which systemic inflammation plays a key role; this provides the basis of novel therapies, several of which are now in clinical trials. Intensive care unit (ICU) therapy parallels that applied in the general ICU population in some organ failures but has peculiar differential characteristics in others. Critical care management strategies and the option of liver transplantation (LT) should be balanced with futility considerations in those with a poor prognosis. Nowadays, LT is the only life-saving treatment that can radically improve the long-term prognosis of patients with ACLF. This narrative review will provide insights on the current understanding of ACLF with emphasis on intensive care management.

AXL Expression on Homeostatic Resident Liver Macrophages Is Reduced in Cirrhosis Following GAS6 Production by Hepatic Stellate Cells.

BACKGROUND & AIMS: AXL and MERTK expression on circulating monocytes modulated immune responses in patients with cirrhosis (CD14+HLA-DR+AXL+) and acute-on-chronic liver failure (CD14+MERTK+). AXL expression involved enhanced efferocytosis, sustained phagocytosis, but reduced tumor necrosis factor-α/interleukin-6 production and T-cell activation, suggesting a homeostatic function. Axl was expressed on murine airway in tissues contacting the external environment, but not interstitial lung- and tissue-resident synovial lining macrophages. Here, we assessed AXL expression on tissue macrophages in patients with cirrhosis. METHODS: Using multiplexed immunofluorescence we compared AXL expression in liver biopsies in cirrhosis (n = 22), chronic liver disease (n = 8), non-cirrhotic portal hypertension (n = 4), and healthy controls (n = 4). Phenotype and function of isolated primary human liver macrophages were characterized by flow cytometry (cirrhosis, n = 11; control, n = 14) ex vivo. Also, AXL expression was assessed on peritoneal (n = 29) and gut macrophages (n = 16) from cirrhotic patients. Regulation of AXL expression was analyzed in vitro and ex vivo using primary hepatic stellate cells (HSCs), LX-2 cells, and GAS6 in co-culture experiments. RESULTS: AXL was expressed on resident (CD68+) but not tissue-infiltrating (MAC387+) liver macrophages, hepatocytes, HSCs, or sinusoidal endothelial cells. Prevalence of hepatic CD68+AXL+ cells significantly decreased with cirrhosis progression: (healthy, 90.2%; Child-Pugh A, 76.1%; Child-Pugh B, 64.5%; and Child-Pugh C, 18.7%; all P < .05) and negatively correlated with Model for End-Stage Liver Disease and C-reactive protein (all P < .05). AXL-expressing hepatic macrophages were CD68highHLA-DRhighCD16highCD206high. AXL expression also decreased on gut and peritoneal macrophages from cirrhotic patients but increased in regional lymph nodes. GAS6, enriched in the cirrhotic liver, appeared to be secreted by HSCs and down-regulate AXL in vitro. CONCLUSIONS: Decreased AXL expression on resident liver macrophages in advanced cirrhosis, potentially in response to activated HSC-secreted GAS6, suggests a role for AXL in the regulation of hepatic immune homeostasis.

Sympathetic nervous activation, mitochondrial dysfunction and outcome in acutely decompensated cirrhosis: the metabolomic prognostic models (CLIF-C MET).

BACKGROUND AND AIMS: Current prognostic scores of patients with acutely decompensated cirrhosis (AD), particularly those with acute-on-chronic liver failure (ACLF), underestimate the risk of mortality. This is probably because systemic inflammation (SI), the major driver of AD/ACLF, is not reflected in the scores. SI induces metabolic changes, which impair delivery of the necessary energy for the immune reaction. This investigation aimed to identify metabolites associated with short-term (28-day) death and to design metabolomic prognostic models. METHODS: Two prospective multicentre large cohorts from Europe for investigating ACLF and development of ACLF, CANONIC (discovery, n=831) and PREDICT (validation, n=851), were explored by untargeted serum metabolomics to identify and validate metabolites which could allow improved prognostic modelling. RESULTS: Three prognostic metabolites strongly associated with death were selected to build the models. 4-Hydroxy-3-methoxyphenylglycol sulfate is a norepinephrine derivative, which may be derived from the brainstem response to SI. Additionally, galacturonic acid and hexanoylcarnitine are associated with mitochondrial dysfunction. Model 1 included only these three prognostic metabolites and age. Model 2 was built around 4-hydroxy-3-methoxyphenylglycol sulfate, hexanoylcarnitine, bilirubin, international normalised ratio (INR) and age. In the discovery cohort, both models were more accurate in predicting death within 7, 14 and 28 days after admission compared with MELDNa score (C-index: 0.9267, 0.9002 and 0.8424, and 0.9369, 0.9206 and 0.8529, with model 1 and model 2, respectively). Similar results were found in the validation cohort (C-index: 0.940, 0.834 and 0.791, and 0.947, 0.857 and 0.810, with model 1 and model 2, respectively). Also, in ACLF, model 1 and model 2 outperformed MELDNa 7, 14 and 28 days after admission for prediction of mortality. CONCLUSIONS: Models including metabolites (CLIF-C MET) reflecting SI, mitochondrial dysfunction and sympathetic system activation are better predictors of short-term mortality than scores based only on organ dysfunction (eg, MELDNa), especially in patients with ACLF.

Lysophosphatidylcholines modulate immunoregulatory checkpoints in peripheral monocytes and are associated with mortality in people with acute liver failure.

BACKGROUND & AIMS: Acute liver failure (ALF) is a life-threatening disease characterised by high-grade inflammation and immunoparesis, which is associated with a high incidence of death from sepsis. Herein, we aimed to describe the metabolic dysregulation in ALF and determine whether systemic immune responses are modulated via the lysophosphatidylcholine (LPC)-autotaxin (ATX)-lysophosphatidylcholinic acid (LPA) pathway. METHODS: Ninety-six individuals with ALF, 104 with cirrhosis, 31 with sepsis and 71 healthy controls (HCs) were recruited. Pathways of interest were identified by multivariate statistical analysis of proton nuclear magnetic resonance spectroscopy and untargeted ultraperformance liquid chromatography-mass spectrometry-based lipidomics. A targeted metabolomics panel was used for validation. Peripheral blood mononuclear cells were cultured with LPA 16:0, 18:0, 18:1, and their immune checkpoint surface expression was assessed by flow cytometry. Transcript-level expression of the LPA receptor (LPAR) in monocytes was investigated and the effect of LPAR antagonism was also examined in vitro. RESULTS: LPC 16:0 was highly discriminant between ALF and HC. There was an increase in ATX and LPA in individuals with ALF compared to HCs and those with sepsis. LPCs 16:0, 18:0 and 18:1 were reduced in individuals with ALF and were associated with a poor prognosis. Treatment of monocytes with LPA 16:0 increased their PD-L1 expression and reduced CD155, CD163, MerTK levels, without affecting immune checkpoints on T and NK/CD56+T cells. LPAR1 and 3 antagonism in culture reversed the effect of LPA on monocyte expression of MerTK and CD163. MerTK and CD163, but not LPAR genes, were differentially expressed and upregulated in monocytes from individuals with ALF compared to controls. CONCLUSION: Reduced LPC levels are biomarkers of poor prognosis in individuals with ALF. The LPC-ATX-LPA axis appears to modulate innate immune response in ALF via LPAR1 and LPAR3. Further investigations are required to identify novel therapeutic agents targeting these receptors. IMPACT AND IMPLICATIONS: We identified a metabolic signature of acute liver failure (ALF) and investigated the immunometabolic role of the lysophosphatidylcholine-autotaxin-lysophosphatidylcholinic acid pathway, with the aim of finding a mechanistic explanation for monocyte behaviour and identifying possible therapeutic targets (to modulate the systemic immune response in ALF). At present, no selective immune-based therapies exist. We were able to modulate the phenotype of monocytes in vitro and aim to extend these findings to murine models of ALF as a next step. Future therapies may be based on metabolic modulation; thus, the role of specific lipids in this pathway require elucidation and the relative merits of autotaxin inhibition, lysophosphatidylcholinic acid receptor blockade or lipid-based therapies need to be determined. Our findings begin to bridge this knowledge gap and the methods used herein could be useful in identifying therapeutic targets as part of an experimental medicine approach.

Plasma exchange in the intensive care unit: a narrative review.

In this narrative review, we discuss the relevant issues of therapeutic plasma exchange (TPE) in critically ill patients. For many conditions, the optimal indication, device type, frequency, duration, type of replacement fluid and criteria for stopping TPE are uncertain. TPE is a potentially lifesaving but also invasive procedure with risk of adverse events and complications and requires close monitoring by experienced teams. In the intensive care unit (ICU), the indications for TPE can be divided into (1) absolute, well-established, and evidence-based, for which TPE is recognized as first-line therapy, (2) relative, for which TPE is a recognized second-line treatment (alone or combined) and (3) rescue therapy, where TPE is used with a limited or theoretical evidence base. New indications are emerging and ongoing knowledge gaps, notably regarding the use of TPE during critical illness, support the establishment of a TPE registry dedicated to intensive care medicine.

Rifaximin-α reduces gut-derived inflammation and mucin degradation in cirrhosis and encephalopathy: RIFSYS randomised controlled trial.

BACKGROUND & AIMS: Rifaximin-α is efficacious for the prevention of recurrent hepatic encephalopathy (HE), but its mechanism of action remains unclear. We postulated that rifaximin-α reduces gut microbiota-derived endotoxemia and systemic inflammation, a known driver of HE. METHODS: In a placebo-controlled, double-blind, mechanistic study, 38 patients with cirrhosis and HE were randomised 1:1 to receive either rifaximin-α (550 mg BID) or placebo for 90 days. PRIMARY OUTCOME: 50% reduction in neutrophil oxidative burst (OB) at 30 days. SECONDARY OUTCOMES: changes in psychometric hepatic encephalopathy score (PHES) and neurocognitive functioning, shotgun metagenomic sequencing of saliva and faeces, plasma and faecal metabolic profiling, whole blood bacterial DNA quantification, neutrophil toll-like receptor (TLR)-2/4/9 expression and plasma/faecal cytokine analysis. RESULTS: Patients were well-matched: median MELD (11 rifaximin-α vs. 10 placebo). Rifaximin-α did not lead to a 50% reduction in spontaneous neutrophil OB at 30 days compared to baseline (p = 0.48). However, HE grade normalised (p = 0.014) and PHES improved (p = 0.009) after 30 days on rifaximin-α. Rifaximin-α reduced circulating neutrophil TLR-4 expression on day 30 (p = 0.021) and plasma tumour necrosis factor-α (TNF-α) (p <0.001). Rifaximin-α suppressed oralisation of the gut, reducing levels of mucin-degrading sialidase-rich species, Streptococcus spp, Veillonella atypica and parvula, Akkermansia and Hungatella. Rifaximin-α promoted a TNF-α- and interleukin-17E-enriched intestinal microenvironment, augmenting antibacterial responses to invading pathobionts and promoting gut barrier repair. Those on rifaximin-α were less likely to develop infection (odds ratio 0.21; 95% CI 0.05-0.96). CONCLUSION: Rifaximin-α led to resolution of overt and covert HE, reduced the likelihood of infection, reduced oralisation of the gut and attenuated systemic inflammation. Rifaximin-α plays a role in gut barrier repair, which could be the mechanism by which it ameliorates bacterial translocation and systemic endotoxemia in cirrhosis. CLINICAL TRIAL NUMBER: ClinicalTrials.gov NCT02019784. LAY SUMMARY: In this clinical trial, we examined the underlying mechanism of action of an antibiotic called rifaximin-α which has been shown to be an effective treatment for a complication of chronic liver disease which effects the brain (termed encephalopathy). We show that rifaximin-α suppresses gut bacteria that translocate from the mouth to the intestine and cause the intestinal wall to become leaky by breaking down the protective mucus barrier. This suppression resolves encephalopathy and reduces inflammation in the blood, preventing the development of infection.

COVID-19 hospital activity and in-hospital mortality during the first and second waves of the pandemic in England: an observational study.

INTRODUCTION: We aimed to examine the profile of, and outcomes for, all people hospitalised with COVID-19 across the first and second waves of the pandemic in England. METHODS: This was an exploratory retrospective analysis of observational data from the Hospital Episode Statistics data set for England. All patients aged ≥18 years in England with a diagnosis of COVID-19 who had a hospital stay that was completed between 1 March 2020 and 31 March 2021 were included. In-hospital mortality was the primary outcome of interest. The second wave was identified as starting on 1 September 2020. Multilevel logistic regression modelling was used to investigate the relationship between mortality and demographic, comorbidity and temporal covariates. RESULTS: Over the 13 months, 374 244 unique patients had a diagnosis of COVID-19 during a hospital stay, of whom 93 701 (25%) died in hospital. Adjusted mortality rates fell from 40%-50% in March 2020 to 11% in August 2020 before rising to 21% in January 2021 and declining steadily to March 2021. Improvements in mortality rates were less apparent in older and comorbid patients. Although mortality rates fell for all ethnic groups from the first to the second wave, declines were less pronounced for Bangladeshi, Indian, Pakistani, other Asian and black African ethnic groups. CONCLUSIONS: There was a substantial decline in adjusted mortality rates during the early part of the first wave which was largely maintained during the second wave. The underlying reasons for consistently higher mortality risk in some ethnic groups merits further study.

Liver Transplantation Society of India Guidelines for the Management of Acute Liver Injury Secondary to Yellow Phosphorus-Containing Rodenticide Poisoning Using the Modified Delphi Technique of Consensus Development.

BACKGROUND: Acute liver failure caused by the ingestion of yellow phosphorus-containing rodenticide has been increasing in incidence over the last decade and is a common indication for emergency liver transplantation in Southern and Western India and other countries. Clear guidelines for its management are necessary, given its unpredictable course, potential for rapid deterioration and variation in clinical practice. METHODS: A modified Delphi approach was used for developing consensus guidelines under the aegis of the Liver Transplantation Society of India. A detailed review of the published literature was performed. Recommendations for three areas of clinical practice, assessment and initial management, intensive care unit (ICU) management and liver transplantation, were developed. RESULTS: The expert panel consisted of 16 clinicians, 3 nonclinical specialists and 5 senior advisory members from 11 centres. Thirty-one recommendations with regard to criteria for hospital admission and discharge, role of medical therapies, ICU management, evidence for extracorporeal therapies such as renal replacement therapy and therapeutic plasma exchange, early predictors of need for liver transplantation and perioperative care were developed based on published evidence and combined clinical experience. CONCLUSION: Development of these guidelines should help standardise care for patients with yellow phosphorus poisoning and identify areas for collaborative research.

Variability in COVID-19 in-hospital mortality rates between national health service trusts and regions in England: A national observational study for the Getting It Right First Time Programme.

BACKGROUND: A key first step in optimising COVID-19 patient outcomes during future case-surges is to learn from the experience within individual hospitals during the early stages of the pandemic. The aim of this study was to investigate the extent of variation in COVID-19 outcomes between National Health Service (NHS) hospital trusts and regions in England using data from March-July 2020. METHODS: This was a retrospective observational study using the Hospital Episode Statistics administrative dataset. Patients aged ≥ 18 years who had a diagnosis of COVID-19 during a hospital stay in England that was completed between March 1st and July 31st, 2020 were included. In-hospital mortality was the primary outcome of interest. In secondary analysis, critical care admission, length of stay and mortality within 30 days of discharge were also investigated. Multilevel logistic regression was used to adjust for covariates. FINDINGS: There were 86,356 patients with a confirmed diagnosis of COVID-19 included in the study, of whom 22,944 (26.6%) died in hospital with COVID-19 as the primary cause of death. After adjusting for covariates, the extent of the variation in-hospital mortality rates between hospital trusts and regions was relatively modest. Trusts with the largest baseline number of beds and a greater proportion of patients admitted to critical care had the lowest in-hospital mortality rates. INTERPRETATION: There is little evidence of clustering of deaths within hospital trusts. There may be opportunities to learn from the experience of individual trusts to help prepare hospitals for future case-surges.

Changes in COVID-19 in-hospital mortality in hospitalised adults in England over the first seven months of the pandemic: An observational study using administrative data.

BACKGROUND: Previous research by our team identified factors associated with in-hospital mortality in patients with a diagnosis of COVID-19 in England between March and May 2020. The aim of the current paper was to investigate the changing role of demographics and co-morbidity, with a particular focus on ethnicity, as risk factors for in-hospital mortality over an extended period. METHODS: This was a retrospective observational study using the Hospital Episode Statistics administrative dataset. All patients aged ≥ 18 years in England with a diagnosis of COVID-19 who had a hospital stay that was completed (discharged alive or died) between 1st March and 30th September 2020 were included. In-hospital mortality was the primary outcome of interest. Multilevel logistic regression was used to model the relationship between in-hospital mortality with adjustment for the covariates: age, sex, deprivation, ethnicity, date of discharge and a number of comorbidities. FINDINGS: Compared to patients in March-May (n = 93,379), patients in June-September (n = 24,059) were younger, more likely to be female and of Asian ethnicity, but less likely to be of Black ethnicity. In-hospital mortality rates, adjusted for covariates, declined from 33-34% in March to 11-12% in September. Compared to the March-May period, Bangladeshi, Indian and Other Asian ethnicity patients had a lower relative odds of death (compared to White ethnicity patients) during June-September. For Pakistani patients, the decline in-hospital mortality rates was more modest across the same time periods with the relative odds of death increasing slightly (odds ratio (95% confidence interval)) 1.24 (1.10 to 1.40) and 1.35 (1.08 to 1.69) respectively. From March-May to June-September the relative odds of death in patients with a diagnosis of metastatic carcinoma increased (1.90 (1.73 to 2.08) vs 3.01 (2.55 to 3.54)) but decreased for male patients (1.44 (1.39 to 1.49) vs 1.27 (1.17 to 1.38)) and patients with obesity (1.42 (1.34 to 1.52) vs 0.97 (0.83 to 1.14)) and diabetes without complications (1.14 (1.10 to 1.19) vs 0.95 (0.87 to 1.05)). INTERPRETATION: In-hospital mortality rates for patients with a diagnosis of COVID-19 have fallen substantially and there is evidence that the relative importance of some covariates has changed since the start of the pandemic. These patterns should continue to be tracked as new variants of the virus emerge, vaccination programmes are rolled out and hospital pressures fluctuate.

Dysregulation of the Lysophosphatidylcholine/Autotaxin/Lysophosphatidic Acid Axis in Acute-on-Chronic Liver Failure Is Associated With Mortality and Systemic Inflammation by Lysophosphatidic Acid-Dependent Monocyte Activation.

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is characterized by systemic inflammation, monocyte dysfunction, and susceptibility to infection. Lysophosphatidylcholines (LPCs) are immune-active lipids whose metabolic regulation and effect on monocyte function in ACLF is open for study. APPROACHES & RESULTS: Three hundred forty-two subjects were recruited and characterized for blood lipid, cytokines, phospholipase (PLA), and autotaxin (ATX) concentration. Peripheral blood mononuclear cells and CD14+ monocytes were cultured with LPC, or its autotaxin (ATX)-derived product, lysophosphatidic acid (LPA), with or without lipopolysaccharide stimulation and assessed for surface marker phenotype, cytokines production, ATX and LPA-receptor expression, and phagocytosis. Hepatic ATX expression was determined by immunohistochemistry. Healthy volunteers and patients with sepsis or acute liver failure served as controls. ACLF serum was depleted in LPCs with up-regulated LPA levels. Patients who died had lower LPC levels than survivors (area under the receiver operating characteristic curve, 0.94; P < 0.001). Patients with high-grade ACLF had the lowest LPC concentrations and these rose over the first 3 days of admission. ATX concentrations were higher in patients with AD and ACLF and correlated with Model for End-Stage Liver Disease, Consortium on Chronic Liver Failure-Sequential Organ Failure Assessment, and LPC/LPA concentrations. Reduction in LPC correlated with higher monocyte Mer-tyrosine-kinase (MerTK) and CD163 expression. Plasma ATX concentrations rose dynamically during ACLF evolution, correlating with IL-6 and TNF-α, and were associated with increased hepatocyte ATX expression. ACLF patients had lower human leukocyte antigen-DR isotype and higher CD163/MerTK monocyte expression than controls; both CD163/MerTK expression levels were reduced in ACLF ex vivo following LPA, but not LPC, treatment. LPA induced up-regulation of proinflammatory cytokines by CD14+ cells without increasing phagocytic capacity. CONCLUSIONS: ATX up-regulation in ACLF promotes LPA production from LPC. LPA suppresses MerTK/CD163 expression and increases monocyte proinflammatory cytokine production. This metabolic pathway could be investigated to therapeutically reprogram monocytes in ACLF.

Patient factors and temporal trends associated with COVID-19 in-hospital mortality in England: an observational study using administrative data.

BACKGROUND: Analysis of the effect of COVID-19 on the complete hospital population in England has been lacking. Our aim was to provide a comprehensive account of all hospitalised patients with COVID-19 in England during the early phase of the pandemic and to identify the factors that influenced mortality as the pandemic evolved. METHODS: This was a retrospective exploratory analysis using the Hospital Episode Statistics administrative dataset. All patients aged 18 years or older in England who completed a hospital stay (were discharged alive or died) between March 1 and May 31, 2020, and had a diagnosis of COVID-19 on admission or during their stay were included. In-hospital death was the primary outcome of interest. Multilevel logistic regression was used to model the relationship between death and several covariates: age, sex, deprivation (Index of Multiple Deprivation), ethnicity, frailty (Hospital Frailty Risk Score), presence of comorbidities (Charlson Comorbidity Index items), and date of discharge (whether alive or deceased). FINDINGS: 91 541 adult patients with COVID-19 were discharged during the study period, among which 28 200 (30·8%) in-hospital deaths occurred. The final multilevel logistic regression model accounted for age, deprivation score, and date of discharge as continuous variables, and sex, ethnicity, and Charlson Comorbidity Index items as categorical variables. In this model, significant predictors of in-hospital death included older age (modelled using restricted cubic splines), male sex (1·457 [1·408-1·509]), greater deprivation (1·002 [1·001-1·003]), Asian (1·211 [1·128-1·299]) or mixed ethnicity (1·317 [1·080-1·605]; vs White ethnicity), and most of the assessed comorbidities, including moderate or severe liver disease (5·433 [4·618-6·392]). Later date of discharge was associated with a lower odds of death (0·977 [0·976-0·978]); adjusted in-hospital mortality improved significantly in a broadly linear fashion, from 52·2% in the first week of March to 16·8% in the last week of May. INTERPRETATION: Reductions in the adjusted probability of in-hospital mortality for COVID-19 patients over time might reflect the impact of changes in hospital strategy and clinical processes. The reasons for the observed improvements in mortality should be thoroughly investigated to inform the response to future outbreaks. The higher mortality rate reported for certain ethnic minority groups in community-based studies compared with our hospital-based analysis might partly reflect differential infection rates in those at greatest risk, propensity to become severely ill once infected, and health-seeking behaviours. FUNDING: None.

COVID-19: What we've done well and what we could or should have done better-the 4 Ps.

The current coronavirus pandemic has impacted heavily on ICUs worldwide. Although many hospitals and healthcare systems had plans in place to manage multiple casualties as a result of major natural disasters or accidents, there was insufficient preparation for the sudden, massive influx of severely ill patients with COVID-19. As a result, systems and staff were placed under immense pressure as everyone tried to optimize patient management. As the pandemic continues, we must apply what we have learned about our response, both good and bad, to improve organization and thus patient care in the future.

PD-1 blockade improves Kupffer cell bacterial clearance in acute liver injury.

Patients with acute liver failure (ALF) have systemic innate immune suppression and increased susceptibility to infections. Programmed cell death 1 (PD-1) expression by macrophages has been associated with immune suppression during sepsis and cancer. We therefore examined the role of the programmed cell death 1/programmed death ligand 1 (PD-1/PD-L1) pathway in regulating Kupffer cell (KC) inflammatory and antimicrobial responses in acetaminophen-induced (APAP-induced) acute liver injury. Using intravital imaging and flow cytometry, we found impaired KC bacterial clearance and systemic bacterial dissemination in mice with liver injury. We detected increased PD-1 and PD-L1 expression in KCs and lymphocyte subsets, respectively, during injury resolution. Gene expression profiling of PD-1+ KCs revealed an immune-suppressive profile and reduced pathogen responses. Compared with WT mice, PD-1-deficient mice and anti-PD-1-treated mice with liver injury showed improved KC bacterial clearance, a reduced tissue bacterial load, and protection from sepsis. Blood samples from patients with ALF revealed enhanced PD-1 and PD-L1 expression by monocytes and lymphocytes, respectively, and that soluble PD-L1 plasma levels could predict outcomes and sepsis. PD-1 in vitro blockade restored monocyte functionality. Our study describes a role for the PD-1/PD-L1 axis in suppressing KC and monocyte antimicrobial responses after liver injury and identifies anti-PD-1 immunotherapy as a strategy to reduce infection susceptibility in ALF.

Leucocyte ratios are biomarkers of mortality in patients with acute decompensation of cirrhosis and acute-on-chronic liver failure.

BACKGROUND: In patients with cirrhosis, progression to acute decompensation (AD) and acute-on-chronic liver failure (ACLF) has been associated with poor prognosis. Differential leucocyte ratios might predict mortality in systemic inflammatory conditions. AIM: To evaluate differential leucocyte ratios as prognostic biomarkers in patients with cirrhosis. METHODS: Patients with AD and ACLF were recruited from four centres in three countries. Peripheral blood differential leucocytes were measured (three centres using flow cytometry) on hospital admission and at 48 hours. Ratios were correlated to model for end-stage liver disease (MELD), chronic liver failure-sequential organ failure (CLIF-SOFA), suspected/culture-positive bacterial infection and survival. RESULTS: Nine hundred twenty-six patients (562 (61%) male, median age 55 (25-94) years) were studied. Overall, 350 (37%) did not survive to hospital discharge. Neutrophil-lymphocyte ratio (NLR) and monocyte-lymphocyte ratio (MLR) were elevated in patients with AD and ACLF who died during their hospital stay. On multivariate analysis NLR retained statistical significance independently of CLIF-SOFA or MELD. NLR >30 was associated with an 80% 90-day mortality in patients with ACLF but not AD. On sensitivity analysis for subgroups (alcohol-related liver disease and suspected sepsis), NLR and MLR retained statistically robust accuracy for the prediction of mortality. Significant predictive accuracy was only observed in centres using flow cytometry. CONCLUSION: Leucocyte ratios are simple and robust biomarkers of outcome in ACLF, which are comparable to CLIF-SOFA score but dependent on leucocyte quantification method. NLR and MLR may be used as screening tools for mortality prediction in patients with acutely deteriorating cirrhosis.

Correction to: Expert statement on the ICU management of patients with thrombotic thrombocytopenic purpura.

The original version of this article unfortunately contained a mistake. The penultimate row of Table 4 shows INR > 1.5 which is incorrect. The correct figure is INR < 1.5. The authors apologize for the mistake. The correct table is given below.

Expression of AXL receptor tyrosine kinase relates to monocyte dysfunction and severity of cirrhosis.

Infectious complications in patients with cirrhosis frequently initiate episodes of decompensation and substantially contribute to the high mortality. Mechanisms of the underlying immuneparesis remain underexplored. TAM receptors (TYRO3/AXL/MERTK) are important inhibitors of innate immune responses. To understand the pathophysiology of immuneparesis in cirrhosis, we detailed TAM receptor expression in relation to monocyte function and disease severity prior to the onset of acute decompensation. TNF-α/IL-6 responses to lipopolysaccharide were attenuated in monocytes from patients with cirrhosis (n = 96) compared with controls (n = 27) and decreased in parallel with disease severity. Concurrently, an AXL-expressing (AXL+) monocyte population expanded. AXL+ cells (CD14+CD16highHLA-DRhigh) were characterised by attenuated TNF-α/IL-6 responses and T cell activation but enhanced efferocytosis and preserved phagocytosis of Escherichia coli Their expansion correlated with disease severity, complications, infection, and 1-yr mortality. AXL+ monocytes were generated in response to microbial products and efferocytosis in vitro. AXL kinase inhibition and down-regulation reversed attenuated monocyte inflammatory responses in cirrhosis ex vivo. AXL may thus serve as prognostic marker and deserves evaluation as immunotherapeutic target in cirrhosis.

CD8+T cells from patients with cirrhosis display a phenotype that may contribute to cirrhosis-associated immune dysfunction.

BACKGROUND: Cirrhosis-associated immune dysfunction (CAID) contributes to high sepsis risk in patients with chronic liver disease. Various innate and; to a lesser extent; adaptive immune dysfunctions have been described as contributors to CAID leading to immune-paresis and impaired anti-microbial response in cirrhosis. In this study, we examined the phenotype of CD8+T cells in chronic liver disease with the aim to evaluate changes that might contribute to impaired immune responses. METHODS: Sixty patients with cirrhosis were prospectively recruited for this study. CD8+T cells from peripheral blood, ascites and liver explants were characterized using flow cytometry and immunohistochemistry, respectively. The transcriptional signature of flow-sorted HLA-DR+CD8+T cells was performed using Nanostring™ technology. HLA-DR+CD8+T cells interactions with PBMCs and myeloid cells were tested in vitro. FINDINGS: Peripheral CD8+T cells from cirrhotic patients displayed an altered phenotype characterized by high HLA-DR and TIM-3 surface expression associated with concomitant infections and disease severity, respectively. Paired peritoneal CD8+T cells expressed more pronounced levels of HLA-DR and PD-1 compared to peripheral CD8+T cells. HLA-DR+CD8+T cells were enriched in cirrhotic livers compared to controls. TIM-3, CTLA-4 and PD-1 levels were highly expressed on HLA-DR+CD8+T cells and co-expression of HLA-DR and PD1 was higher in patients with poor disease outcomes. Genes involved in cytokines production and intracellular signalling pathways were strongly down-regulated in HLA-DR+CD8+T cells. In comparison to their HLA-DR- counterparts, HLA-DR+CD8+T cells promoted less proliferation of PBMCs and induced phenotypic and functional dysfunctions in monocytes and neutrophils in vitro. INTERPRETATION: In patients with cirrhosis, CD8+T cells display a phenotypic, functional and transcriptional profile which may contribute to CAID. FUND: This work was supported by Medical Research Council, the Rosetrees Charitable Trust, Robert Tournut 2016 grant (Sociéte Nationale Française de GastroEntérologie), Gilead® sciences, and NIHR Imperial Biomedical Research Centre.