Increased Expression of Cytotoxic T-Lymphocyte-Associated Protein 4 by T Cells, Induced by B7 in Sera, Reduces Adaptive Immunity in Patients With Acute Liver Failure.

BACKGROUND & AIMS: Patients with acute liver failure (ALF) have defects in innate immune responses to microbes (immune paresis) and are susceptible to sepsis. Cytotoxic T-lymphocyte-associated protein 4 (CTLA4), which interacts with the membrane receptor B7 (also called CD80 and CD86), is a negative regulator of T-cell activation. We collected T cells from patients with ALF and investigated whether inhibitory signals down-regulate adaptive immune responses in patients with ALF. METHODS: We collected peripheral blood mononuclear cells from patients with ALF and controls from September 2013 through September 2015 (45 patients with ALF, 20 patients with acute-on-chronic liver failure, 15 patients with cirrhosis with no evidence of acute decompensation, 20 patients with septic shock but no cirrhosis or liver disease, and 20 healthy individuals). Circulating CD4+ T cells were isolated and analyzed by flow cytometry. CD4+ T cells were incubated with antigen, or agonist to CD3 and dendritic cells, with or without antibody against CTLA4; T-cell proliferation and protein expression were quantified. We measured levels of soluble B7 molecules in supernatants of isolated primary hepatocytes, hepatic sinusoidal endothelial cells, and biliary epithelial cells from healthy or diseased liver tissues. We also measured levels of soluble B7 serum samples from patients and controls, and mice with acetaminophen-induced liver injury using enzyme-linked immunosorbent assays. RESULTS: Peripheral blood samples from patients with ALF had a higher proportion of CD4+ CTLA4+ T cells than controls; patients with infections had the highest proportions. CD4+ T cells from patients with ALF had a reduced proliferative response to antigen or CD3 stimulation compared to cells from controls; incubation of CD4+ T cells from patients with ALF with an antibody against CTLA4 increased their proliferative response to antigen and to CD3 stimulation, to the same levels as cells from controls. CD4+ T cells from controls up-regulated expression of CTLA4 after 24-48 hours culture with sera from patients with ALF; these sera were found to have increased concentrations of soluble B7 compared to sera from controls. Necrotic human primary hepatocytes exposed to acetaminophen, but not hepatic sinusoidal endothelial cells and biliary epithelial cells from patients with ALF, secreted high levels of soluble B7. Sera from mice with acetaminophen-induced liver injury contained high levels of soluble B7 compared to sera from mice without liver injury. Plasma exchange reduced circulating levels of soluble B7 in patients with ALF and expression of CTLA4 on T cells. CONCLUSIONS: Peripheral CD4+ T cells from patients with ALF have increased expression of CTLA4 compared to individuals without ALF; these cells have a reduced response to antigen and CD3 stimulation. We found sera of patients with ALF and from mice with liver injury to have high concentrations of soluble B7, which up-regulates CTLA4 expression by T cells and reduces their response to antigen. Plasma exchange reduces levels of B7 in sera from patients with ALF and might be used to restore antimicrobial responses to patients.

Clinical and prognostic associations of liver volume determined by computed tomography in acute liver failure.

BACKGROUND: Liver volume (LV) can be non-invasively determined from the analysis of computed tomography (CT) images, and in patients with acute liver injury (ALI) or failure (ALF), it can reflect the balance of structural collapse with hepatic regeneration. We examined its relation to cause of liver injury, measures of liver function and histopathological findings, and utility in prediction of complications and mortality. METHODS: Two hundred and seventy-three patients with ALF/ALI admitted to a specialist intensive care unit were studied. One hundred and ninety-nine patients (73%) had non-acetaminophen (NA) aetiologies and 74 (27%) had acetaminophen-induced disease. LV and proportion of predicted LV (PLV%) were determined from admission CT imaging. RESULTS: LV and PLV% showed marked variation when aetiologic groups were compared (P < .0001), including loss in cases with indeterminate cause (LV 939 cm3 [IQR 680-1259], PLV% 56% [42-84]) and increase in Budd-Chiari syndrome (1891 cm3 [1601-2094], 121% [111-131]). Progression to high-grade encephalopathy was more common with smaller LV and PLV. A < 1000 cm3 threshold identified NA patients who later developed it with 93% (95%CI 83-98) specificity and odds ratio 10.6 (3.3-34.5) at median 5 days prior to onset, and risk of death in those with NA-drug-induced (DILI) or indeterminate disease with 91% (71-99) specificity and 63% (50-75) sensitivity. CONCLUSION: In patients with ALF/ALI, LV shows marked variation by the cause of disease, and in prognostic importance. In indeterminate and DILI cases, loss of volume to <1000 cm3 may indicate irreversible liver injury and regenerative failure and serve as an early clinical predictor for the development of high-grade encephalopathy and death.

Interlobar Artery Resistive Index predicts Acute-on-Chronic Liver Failure Syndrome in Cirrhotic Patients with Acute Decompensation.

INTRODUCTION: Patients with acutely decompensated (AD) cirrhosis are at risk for developing acute-on-chronic liver failure (ACLF) syndrome. This syndrome is associated with a high short-term mortality rate. The aim of our study was to identify reliable early predictors of developing ACLF in cirrhotic patients with AD. PATIENTS AND METHODS: We assessed 84 cirrhotic patients admitted for AD without ACLF on admission. We performed routine blood testing and detailed ultrasound Doppler studies of systemic arteries and mayor abdominal veins and arteries. We also calculated liver-specific and intensive care unit predictive scores. The area under the ROC curve (AUROC) was calculated for all variables that were significantly different between patients who developed ACLF and those who did not. Sensitivity, specificity, positive and negative predictive values, as well as diagnostic accuracy predicting the short-term development of ACLF were determined. RESULTS: of the 84 patients, 23 developed ACLF whereas 61 did not. In the univariate analysis, serum levels of creatinine and urea, prothrombin time ratio, MELD score, portal vein and femoral artery flow velocity as well as the renal and interlobar artery resistive indices (RI) were associated with the short-term development of ACLF. However, only interlobar artery RI had independent predictive value in the multivariate analysis. The AUROC value for RI of the interlobar arteries was 0.9971. CONCLUSION: On the first day of admission, ultrasound measurement of the RI of the interlobar arteries recognizes with high predictive accuracy those cirrhotic patients admitted with AD who will develop ACLF during hospital admission.

Increased Survival for Patients With Cirrhosis and Organ Failure in Liver Intensive Care and Validation of the Chronic Liver Failure-Sequential Organ Failure Scoring System.

BACKGROUND & AIMS: During the past decade, survival has increased among patients admitted to general intensive care units, but it is not clear if it has increased for patients admitted with cirrhosis and organ failure. The chronic liver failure-sequential organ failure assessment (CLIF-SOFA) recently was developed as an adaptation to the SOFA to predict outcomes of patients, but requires validation. We investigated changes in outcomes of patients with cirrhosis and organ failure since 2000, compared the abilities of SOFA and CLIF-SOFA to predict patient survival, and validated the CLIF-SOFA system. METHODS: In a retrospective study, we collected data from 971 patients (median age, 52 y; age range, 16-90 y; 62% male) with cirrhosis (54% alcohol associated, 12% viral, and 34% other causes). The patients were admitted under emergency conditions from January 1, 2000, to December 31, 2010, to a liver intensive therapy unit in the United Kingdom. Patient survival while in the hospital was compared with measures of illness severity, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, model for end-stage liver disease (MELD) scores, SOFA scores, and CLIF-SOFA scores. RESULTS: Patients had a median APACHE II score of 21 (range, 5-50) and a median MELD score of 23 (range, 6-40). The median APACHE II score at admission decreased from 23 to 22 over the study period (P < .001), whereas the median MELD score at admission decreased from 23 to 18 (P < .001). Overall survival until hospital discharge was 51%; this value increased from 40% in 2000 to 63% in 2010 (P < .001). The unadjusted odds ratio for change in mortality/year was 0.87 (95% confidence interval, 0.83-0.91; P < .001). The APACHE II score adjusted odds ratio for mortality was 0.89 (95% confidence interval, 0.84-0.93; P < .001). The etiology of cirrhosis was not associated with a significant difference in survival. CLIF-SOFA and SOFA scores at the time of admission predicted patient survival with area under the receiver operating curve (AUROC) values of 0.813 and 0.799, respectively; the scores at 48 hours after admission predicted survival with AUROC values of 0.853 and 0.840, and scores after 1 week predicted survival with AUROC values of 0.842 and 0.844, respectively. These AUROC values were higher than those obtained from APACHE II or MELD scores. CONCLUSIONS: The proportion of patients with cirrhosis who survived after admission to intensive care increased from 2000 to 2010. SOFA and CLIF-SOFA scores during the first week of critical care appear to have similar abilities to predict patient survival.

Aerobic capacity during cardiopulmonary exercise testing and survival with and without liver transplantation for patients with chronic liver disease.

Chronic liver disease (CLD) is associated with muscle wasting, reduced exercise tolerance and aerobic capacity (AC). Measures of AC determined with cardiopulmonary exercise testing (CPET) may predict survival after liver transplantation (LT), but the relationship with nontransplant outcomes is uncertain. In patients assessed for LT, we examined the relationship of CPET AC parameters with the severity of liver disease, nutritional state, and survival with and without LT. Patients assessed for elective first LT who underwent CPET and an anthropometric assessment at a single center were studied. CPET-derived measures of AC that were evaluated included the peak oxygen consumption (VO2 peak) and the anaerobic threshold (AT). Three hundred ninety-nine patients underwent CPET, and 223 underwent LT; 45% of the patients had a VO2 peak < 50% of the predicted value, and 31% had an AT < 9 mL/kg/minute. The VO2 peak and AT values correlated with the Model for End-Stage Liver Disease score, but they more closely correlated with serum sodium and albumin levels. The handgrip strength correlated strongly with the VO2 peak. Patients with impaired AC had prolonged hospitalization after LT, and nonsurvivors had lower AT values than survivors 1 year after transplantation (P < 0.05); this was significant in a multivariate analysis. One hundred seventy-six patients did not undergo LT; the 1-year mortality rate was 34.6%. The AT (P < 0.05) and VO2 peak values (P < 0.001) were lower for nonsurvivors. In a multivariate analysis, AT was independently associated with nonsurvival. In conclusion, AC was markedly impaired in many patients with CLD. In patients who did not undergo transplantation, impaired AT was predictive of mortality, and in patients undergoing LT, it was related to postoperative hospitalization and survival. AC should be evaluated as a modifiable factor for improving patient survival whether or not LT is anticipated.

Portopulmonary hypertension: improved detection using CT and echocardiography in combination.

OBJECTIVES: To establish the relationship between CT signs of pulmonary hypertension and mean pulmonary artery pressure (mPAP) in patients with liver disease, and to determine the additive value of CT in the detection of portopulmonary hypertension in combination with transthoracic echocardiography. METHODS: Forty-nine patients referred for liver transplantation were retrospectively reviewed. Measured CT signs included the main pulmonary artery/ascending aorta diameter ratio (PA/AAmeas) and the mean left and right main PA diameter (RLPAmeas). Enlargement of the pulmonary artery compared to the ascending aorta was also assessed visually (PA/AAvis). CT measurements were correlated with right-sided heart catheter-derived mPAP. The ability of PA/AAvis combined with echocardiogram-derived right ventricular systolic pressure (RVSP) to detect portopulmonary hypertension was tested with ROC analysis. RESULTS: There were moderate correlations between mPAP and both PA/AAmeas and RLPAmeas (rs = 0.41 and rs = 0.42, respectively; p < 0.005). Compared to transthoracic echocardiography alone (AUC = 0.59, p = 0.23), a diagnostic algorithm incorporating PA/AAvis and transthoracic echocardiography-derived RVSP improved the detection of portopulmonary hypertension (AUC = 0.8, p < 0.0001). CONCLUSIONS: CT contributes to the non-invasive detection of portopulmonary hypertension when used in a diagnostic algorithm with transthoracic echocardiography. CT may have a role in the pre-liver transplantation triage of patients with portopulmonary hypertension for right-sided heart catheterisation. KEY POINTS: • CT signs correlate with right-sided heart catheter data in portopulmonary hypertension • CT adds to the transthoracic echocardiography detection of portopulmonary hypertension • CT may have a complementary role in pre-liver transplantation triage.

Development and validation of a dynamic outcome prediction model for paracetamol-induced acute liver failure: a cohort study.

BACKGROUND: Early, accurate prediction of survival is central to management of patients with paracetamol-induced acute liver failure to identify those needing emergency liver transplantation. Current prognostic tools are confounded by recent improvements in outcome independent of emergency liver transplantation, and constrained by static binary outcome prediction. We aimed to develop a simple prognostic tool to reflect current outcomes and generate a dynamic updated estimation of risk of death. METHODS: Patients with paracetamol-induced acute liver failure managed at intensive care units in the UK (London, Birmingham, and Edinburgh) and Denmark (Copenhagen) were studied. We developed prognostic models, excluding patients who underwent transplantation, using Cox proportional hazards in a derivation dataset, and tested in initial and recent external validation datasets. Mortality was estimated in patients who had emergency liver transplantation. Model discrimination was assessed using area under receiver operating characteristic curve (AUROC) and calibration by root mean square error (RMSE). Admission (day 1) variables of age, Glasgow coma scale, arterial pH and lactate, creatinine, international normalised ratio (INR), and cardiovascular failure were used to derive an initial predictive model, with a second (day 2) model including additional changes in INR and lactate. FINDINGS: We developed and validated new high-performance statistical models to support decision making in patients with paracetamol-induced acute liver failure. Applied to the derivation dataset (n=350), the AUROC for 30-day survival was 0·92 (95% CI 0·88-0·96) using the day 1 model and 0·93 (0·88-0·97) using the day 2 model. In the initial validation dataset (n=150), the AUROC for 30-day survival was 0·89 (0·84-0·95) using the day 1 model and 0·90 (0·85-0·95) using the day 2 model. Assessment of calibration using RMSE in prediction of 30-day survival gave values of 0·1642 for the day 1 model and 0·0626 for the day 2 model. In the external validation dataset (n=412), the AUROC for 30-day survival was 0·91 (0·87-0·94) using the day 1 model and 0·91 (0·88-0·95) using the day 2 model, and assessment of calibration using RMSE gave values of 0·079 for the day 1 model and 0·107 for the day 2 model. Applied to patients who underwent emergency liver transplantation (n=116), median predicted 30-day survival was 51% (95% CI 33-85). INTERPRETATION: The models developed here show very good discrimination and calibration, confirmed in independent datasets, and suggest that many patients undergoing transplantation based on existing criteria might have survived with medical management alone. The role and indications for emergency liver transplantation in paracetamol-induced acute liver failure require re-evaluation. FUNDING: Foundation for Liver Research.

Voriconazole hepatotoxicity in severe liver dysfunction.

UNLABELLED: There are no studies regarding to these effects in patients with severe liver dysfunction. OBJECTIVES: The aims of this study were to characterize voriconazole hepatotoxicity in patients with severe liver dysfunction and to compare it with a matched cohort treated with liposomal amphotericin B. METHODS: This is an observational study, in which adults patients treated with at least 4 doses of voriconazole were included. Patients treated with liposomal amphotericin B were used as control group. RESULTS: Sixty nine percent of patients treated with voriconazole showed changes in liver function tests (LFTs) during therapy. They showed elevated transaminases in 35%, cholestasis in 15% or a combination of both in 45%. According to the CTC classification, all patients with hepatotoxicity had a severe reaction. The Roussel Uclaf Causality Assessment Method score in all patients with hepatotoxicity was greater than 8. There was a correlation between initial loading dose greater than 300 mg (4.5 mg/kg) and the risk of hepatotoxicity (p < 0.001). The control group developed alterations in the LFTs in only 10.3% of patients. CONCLUSION: Voriconazole should be used with caution in patients with severe liver dysfunction and following liver transplantation, with frequent monitoring of LFTs or using liposomal amphotericin B instead.