Utility of the MAYO End-Stage Liver Disease score, King's College Criteria, and a new in-hospital mortality score in the prognosis of in-hospital mortality in acute liver failure

Pediatric chronic liver failure-sequential organ failure assessment score and outcome of acute liver failure in children

Aim of the study

Liver transplantation remains the only definitive treatment for children with acute liver failure proven to have irreversible liver injury. Many prognostic models have been used for outcome prediction in pediatric acute liver failure to select patients in a real need of liver transplantation, but unfortunately all have shown inconsistent reproducibility and prognostic accuracy. The aim of this study was to evaluate the pediatric chronic liver failure sequential organ failure assessment (pCLIF-SOFA) score as a predictor of pediatric acute liver failure outcome.

Material and methods

Clinical and laboratory data of 41 children with acute liver failure admitted to the National Liver Institute – Menoufia University were collected retrospectively and used for calculation of both pCLIF-SOFA and Pediatric End-Stage Liver Disease (PELD)/Model for End-Stage Liver Disease (MELD) scores on the day of admission, then statistical analysis was performed to identify the ability of these scores to predict the outcome.

Results

According to the outcome, children enrolled in this study were allocated to survived (n = 16) and died (n = 25) groups, which were age and sex matched. The non-survival group had significantly higher values of both pCLIF-SOFA score (11 [7-13]) and PELD/MELD score (36 [18-42]) than those of the survival group (8 [7-11], 27.5 [15-45]; p < 0.001, p = 0.004) respectively. Both pCLIF-SOFA and PELD/MELD scores at cut-off values > 8 and > 30 respectively on admission could predict death in children with acute liver failure (ALF) with high sensitivity, but with higher specificity, positive and negative predictive values for pCLIF-SOFA.

Conclusions

pCLIF-SOFA is a good predictor of death in pediatric acute liver failure.

The decreasing predictive power of MELD in an era of changing etiology of liver disease

The field of liver transplantation has shifted considerably in the MELD era, including changing allocation, immunosuppression, and liver failure etiologies, as well as better supportive therapies. Our aim was to evaluate the predictive accuracy of the MELD score over time. The United Network for Organ Sharing provided de-identified data on 120 156 patients listed for liver transplant from 2002-2016. The ability of the MELD score to predict 90-day mortality was evaluated by a concordance (C-) statistic and corroborated with competing risk analysis. The MELD score's concordance with 90-day mortality has downtrended from 0.80 in 2003 to 0.70 in 2015. While lab MELD scores at listing and transplant climbed in that interval, score at waitlist death remained steady near 35. Listing age increased from 50 to 54 years. HCV-positive status at listing dropped from 33 to 17%. The concordance of MELD and mortality does not differ with age (>60 = 0.73, <60 = 0.74), but is lower in diseases that are increasing most rapidly-alcoholic liver disease and non-alcoholic fatty liver disease-and higher in those that are declining, particularly in HCV-positive patients (HCV positive = 0.77; negative = 0.73). While MELD still predicts mortality, its accuracy has decreased; changing etiology of disease may contribute.

Delta model for end-stage liver disease and delta clinical prognostic indicator as predictors of mortality in patients with viral acute liver failure

Objective:

The objective of the study is to compare the model for end-stage liver disease (MELD) with clinical prognostic indicators (CPI) specifically the change in these parameters after 48 h of admission in predicting the mortality in patients with acute liver failure (ALF) due to acute viral hepatitis.

Materials and Methods:

An open label, investigator-initiated prospective study was conducted that included 41 patients with acute viral hepatitis with ALF. The cases were followed prospectively till death or discharge. The MELD and CPI were calculated at admission and 48 h of admission.

Results:

Patients having no change or worsening in CPI score, i.e., delta CPI more negative had a higher mortality over the next 48 h compared to patients having an improvement in their respective CPI score. Delta CPI predicted adverse outcome better than the presence of any three CPI on admission (P = 0.019). Patients having no change or a worsening in MELD score, i.e., delta MELD more negative, had a higher mortality in the next 48 h compared to the patients having improvement in their respective MELD score. However, MELD >33 on admission was superior to delta MELD in predicting the adverse outcome (P = 0.019).

Conclusion:

Among the patients with ALF due to viral hepatitis, delta CPI was found to be superior to delta MELD in predicting the adverse outcome in patients with viral ALF (P < 0.0001).

Development of a Model to Predict Transplant-free Survival of Patients With Acute Liver Failure

BACKGROUND & AIMS

Patients with acute liver failure (ALF) have a high risk of death that can be substantially reduced with liver transplantation. It is a challenge to predict which patients with ALF will survive without liver transplant because available prognostic scoring systems are inadequate. We devised a mathematical model, using a large dataset collected by the Acute Liver Failure Study Group, which can predict transplant-free survival in patients with ALF.

METHODS

We performed a retrospective analysis of data from 1974 subjects who met criteria for ALF (coagulopathy and hepatic encephalopathy within 26 weeks of the first symptoms, without pre-existing liver disease) enrolled in the Acute Liver Failure Study Group database from January 1, 1998 through June 11, 2013. We randomly assigned the subjects to development and validation cohorts. Data from the development cohort were analyzed to identify factors associated with transplant-free survival (alive without transplantation by 21 days after admission to the study). Statistically significant variables were used to create a multivariable logistic regression model.

RESULTS

Most subjects were women (70%) and white (78%); acetaminophen overdose was the most common cause (48% of subjects). The rate of transplant-free survival was 50%. Admission values of hepatic encephalopathy grade, ALF etiology, vasopressor use, and log transformations of bilirubin and international normalized ratio were significantly associated with transplant-free survival, based on logistic regression analysis. In the validation cohort, the resulting model predicted transplant-free survival with a C statistic value of 0.84, 66.3% accuracy (95% confidence interval, 63.1%-69.4%), 37.1% sensitivity (95% confidence interval, 32.5%-41.8%), and 95.3% specificity (95% confidence interval, 92.9%-97.1%).

CONCLUSIONS

Using data from the Acute Liver Failure Study Group, we developed a model that predicts transplant-free survival of patients with ALF based on easily identifiable hospital admission data. External validation studies are required.

Ability of King's College Criteria and Model for End-Stage Liver Disease Scores to Predict Mortality of Patients With Acute Liver Failure: A Meta-analysis

BACKGROUND & AIMS

Several prognostic factors are used to identify patients with acute liver failure (ALF) who require emergency liver transplantation. We performed a meta-analysis to determine the accuracy of King's College criteria (KCC) versus the model for end-stage liver disease (MELD) scores in predicting hospital mortality among patients with ALF.

METHODS

We performed a systematic search of the literature for articles published from 2001 through 2015 that compared the accuracy of the KCC with MELD scores in predicting hospital mortality in patients with ALF. We identified 23 studies (comprising 2153 patients) and assessed the quality of data, and then performed a meta-analysis of pooled sensitivity and specificity values, diagnostic odds ratios (DORs), and summary receiver operating characteristic curves. Subgroups analyzed included study quality, era, location (Europe vs non-Europe), and size; ALF etiology (acetaminophen-associated ALF [AALF] vs nonassociated [NAALF]); and whether or not the study included patients who underwent liver transplantation and if the study center was also a transplant center.

RESULTS

The DOR for the KCC was 5.3 (95% confidence interval [CI], 3.7-7.6; 57% heterogeneity) and the DOR for MELD score was 7.0 (95% CI, 5.1-9.7; 48% heterogeneity), so the MELD score and KCC are comparable in overall accuracy. The summary area under the receiver operating characteristic curve values was 0.76 for the KCC and 0.78 for MELD scores. The KCC identified patients with AALF who died with 58% sensitivity (95% CI, 51%-65%) and 89% specificity (95% CI, 85%-93%), whereas MELD scores identified patients with AALF who died with 80% sensitivity (95% CI, 74%-86%) and 53% specificity (95% CI, 47%-59%). The KCC predicted hospital mortality in patients with NAALF with 58% sensitivity (95% CI, 54%-63%) and 74% specificity (95% CI, 69%-78%), whereas MELD scores predicted hospital mortality in patients with NAALF with 76% sensitivity (95% CI, 72%-80%) and 73% specificity (95% CI, 69%-78%). In patients with AALF, the KCC's DOR was 10.4 (95% CI, 4.9-22.1) and the MELD score's DOR was 6.6 (95% CI, 2.1-20.2). In patients with NAALF, the KCC's DOR was 4.16 (95% CI, 2.34-7.40) and the MELD score's DOR was 8.42 (95% CI, 5.98-11.88).

CONCLUSIONS

Based on a meta-analysis of studies, the KCC more accurately predicts hospital mortality among patients with AALF, whereas MELD scores more accurately predict mortality among patients with NAALF. However, there is significant heterogeneity among studies and neither system is optimal for all patients. Given the importance of specificity in decision making for listing for emergency liver transplantation, MELD scores should not replace the KCC in predicting hospital mortality of patients with AALF, but could have a role for NAALF.

Predictive value of serum actin-free Gc-globulin for complications and outcome in acute liver failure

This prospective study was designed to evaluate whether early changes in actin-free Gc-globulin levels were associated with complications and outcomes and to identify factors associated with persistent low actin-free Gc-globulin levels in acute liver failure (ALF). Thirty-two consecutive ALF patients admitted from October 2011 to December 2012 were followed up until death or complete recovery. All had serum actin-free Gc-globulin estimation at admission and at day three or expiry. Logistic regression analysis was performed to identify independent predictors of mortality. A receiver operating characteristic curve analysis was also performed. Nonsurvivors had significantly lower median actin-free Gc-globulin levels than survivors (87.32 vs 180 mg/L; P < 0.001). A receiver operating characteristic curve analysis revealed an area under curve (AUC) of 0.771 and showed that serum actin-free Gc-globulin level of ≤124 mg/L would predict mortality with 92% sensitivity and 71.4% specificity. Patients with lower serum actin-free Gc-globulin levels and decreasing trend in serum actin-free Gc-globulin levels were found to have more mortality and developed more complications. Logistic regression analysis showed that serum actin-free Gc-globulin, total leucocyte count and serum creatinine at admission were independent predictors of mortality. Incorporating these variables, a score predicting mortality risk at admission was derived. The scoring system was compared to MELD score and King's College Criteria as individual predictor of mortality. Serum actin-free Gc-globulin level at presentation is predictive of outcome and can be used for risk stratification. Its persistent low-level predicts mortality and is correlated with various complications.

Changing etiologies and outcomes of acute liver failure: perspectives from 6 transplant centers in Argentina

There is significant geographic variation in the etiologies and prognoses of acute liver failure (ALF). The aims of the present study were to determine the causes and short-term outcomes of ALF in Argentina, to evaluate the performance of prognostic criteria, and to identify clinical prognostic factors of death. We performed a retrospective analysis of 154 adult patients with ALF who were admitted to 6 liver transplantation (LT) programs between June 2005 and December 2011. The most frequent causes of ALF were viral hepatitis B (46 patients or 30%), autoimmune hepatitis (AIH; 40 patients or 26%), and indeterminate causes (40 patients or 26%). No acetaminophen (ACM) overdose was reported. One hundred and twenty one patients (78%) were included on the waiting list, and LT was performed for 83 patients (54%). Overall survival rate is now corected to 73%. Multivariate logistic regression identified 2 independent variables associated with adverse outcomes on admission: a Model for End-Stage Liver Disease (MELD) score ≥ 29 and an encephalopathy grade ≥ 3. In a direct comparison using a receiving operating characteristic curve analysis, the MELD score [C statistic = 0.830, 95% confidence interval (CI) = 0.73-0.93] had better prognostic accuracy for predicting outcomes than the Clichy criteria (C statistic = 0.719, 95% CI = 0.58-0.85) or the King's College criteria (C statistic = 0.631, 95% CI = 0.49-0.77). In conclusion, hepatitis B and AIH were the most frequent causes of fulminant hepatic failure in our series, and no cases of ACM overdosing were identified. A MELD score ≥ 29 and an encephalopathy grade ≥ 3 at admission were associated with death. The MELD score at admission showed the highest prognostic accuracy.

Intraoperative predictors of short-term mortality in living donor liver transplantation due to acute liver failure

BACKGROUND

Acute liver failure (ALF) is a rare and fatal disease with rapidly deteriorating clinical features. Many predictive models for ALF outcomes have been tested, but none have been adopted as definitive guidelines for prognosis because of inconsistencies in accuracy. Most prognostic models for ALF are based on preoperative patient conditions, thus ignoring various specific intraoperative features relevant to postoperative outcomes. We investigated whether intraoperative factors predicted short-term mortality due to ALF in living donor liver transplantations (LDLT).

METHODS

We retrospectively collected intraoperative data, including surgical time, fluctuations in mean blood pressure (MBP) and heart rate, mean pulmonary arterial pressure (PAP), central venous pressure (CVP), urine output, laboratory data, oxygen indices (PaO(2)/FiO(2)), administered drugs, and transfusion of packed red blood cells (PRBCs) from 101 patients with ALF who underwent LDLT. After simple relationships of individual intraoperative variables with 1-month posttransplant mortality were analyzed, we examined potentially significant intraoperative variables (P < .10) by a multivariate adjustment process with preoperative indicators of ALF prognosis.

RESULTS

Intraoperative MBP fluctuations, first mean PAP and CVP, last oxygen index, administered calcium chloride, and PRBC transfusion showed individual associations with posttransplant mortality of ALF patients (P < .05). After multivariate adjustment, PRBC transfusion of ≥ 10 pints (odds ratio 4.73; 95% confidence interval [CI] 1.06-21.16) and MBP fluctuations (odds ratio 1.26; 95% CI 1.00-1.58) were identified to be independent predictors of 1-month posttransplant mortality, together with preoperative factors, including severe hepatic encephalopathy, and a Model for End-stage Liver Disease score ≥ 30 points (area under the curve 0.82, P < .001).

CONCLUSION

MBP fluctuations and large blood transfusions were intraoperative predictors of short-term mortality after LDLT due to ALF. Increased attention to intraoperative manifestations should provide valuable prognostic information for ALF.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Immunophenotype predicts outcome in pediatric acute liver failure

OBJECTIVES

We sought to determine whether markers of T-cell immune activation, including soluble interleukin 2 receptor alpha (sIL2Rα) levels predict outcome in pediatric acute liver failure and may target potential candidates for immunomodulatory therapy.

METHODS

We analyzed markers of immune activation in 77 patients with pediatric acute liver failure enrolled in a multinational, multicenter study. The outcomes were survival with native liver, liver transplantation (LT), and death without transplantation within 21 days after enrollment.

RESULTS

Adjusting for multiple comparisons, only normalized serum sIL2Rα level differed significantly among the 3 outcomes, and was significantly higher in patients who died (P=0.02) or underwent LT (P=0.01) compared with those who survived with their native liver. The 37 patients with normal sIL2Rα levels all lived, 30 with their native liver. Of the 15 subjects with markedly high sIL2Rα (≥5000 IU/mL), 5 survived with their native liver, 2 died, and 8 underwent LT.

CONCLUSIONS

Evidence of immune activation is present in some patients who die or undergo LT. Patients with higher sIL2Rα levels were more likely to die or undergo LT within 21 days than those with lower levels. Identifying a subset of patients at risk for poor outcome may form the foundation for targeted clinical trials with immunomodulatory drugs.

Incorporating dynamics for predicting poor outcome in acute liver failure patients

Acute liver failure (ALF), also known as fulminant hepatic failure (FHF), is a devastating clinical syndrome with a high mortality of 60%-90%. An early and exact assessment of the severity of ALF together with prediction of its further development is critical in order to determine the further management of the patient. A number of prognostic models have been used for outcome prediction in ALF patients but they are mostly based on the variables measured at one time point, mostly at admission. ALF patients rarely show a static state: rapid progress to a life threatening situation occurs in many patients. Since ALF is a dynamic process, admission values of prognostic variables change over time during the clinical course of the patient. Kumar et al developed a prognostic model [ALF early dynamic (ALFED)] based on early changes in values of variables which predicted outcome. ALFED is a model which seems to be worthwhile to test in ALF patients in other parts of the world with different aetiologies. Since the exact pathophysiology of ALF is not fully known and is certainly complex, we believe that adding promising variables involved in the pathophysiology of ALF to the dynamic approach might even further improve prognostic performance. We agree with Kumar et al that an improved dynamic prognostic model should be based on simplicity (easily to be performed at the bedside) and accuracy. Our comments presented in this paper may be considered as recommendations for future optimization of ALF prediction models.

Prediction of poor outcome in patients with acute liver failure-systematic review of prediction models

INTRODUCTION

Acute liver failure is a rare disease with high mortality and liver transplantation is the only life saving therapy. Accurate prognosis of ALF is crucial for proper intervention.

AIM

To identify and characterize newly developed prognostic models of mortality for ALF patients, assess study quality, identify important variables and provide recommendations for the development of improved models in the future.

METHODS

The online databases MEDLINE® (1950-2012) and EMBASE® (1980-2012) were searched for English-language articles that reported original data from clinical trials or observational studies on prognostic models in ALF patients. Studies were included if they developed a new model or modified existing prognostic models. The studies were evaluated based on an existing framework for scoring the methodological and reporting quality of prognostic models.

RESULTS

Twenty studies were included, of which 18 reported on newly developed models, 1 on modification of the Kings College Criteria (KCC) and 1 on the Model for End-Stage Liver Disease (MELD). Ten studies compared the newly developed models to previously existing models (e.g. KCC); they all reported that the new models were superior. In the 12-point methodological quality score, only one study scored full points. On the 38-point reporting score, no study scored full points. There was a general lack of reporting on missing values. In addition, none of the studies used performance measures for calibration and accuracy (e.g. Hosmer-Lemeshow statistics, Brier score), and only 5 studies used the AUC as a measure of discrimination.

CONCLUSIONS

There are many studies on prognostic models for ALF but they show methodological and reporting limitations. Future studies could be improved by better reporting and handling of missing data, the inclusion of model calibration aspects, use of absolute risk measures, explicit considerations for variable selection, the use of a more extensive set of reference models and more thorough validation.

Systematic review: acute liver failure - one disease, more than 40 definitions

BACKGROUND

Acute liver failure (ALF) is a clinical syndrome with very high mortality estimates ranging between 60% and 80%.

AIM

To investigate the explicitness and extent of variability in the used ALF definitions in the ALF prognostic literature.

METHODS

All studies that pertain to the prognosis of patients with ALF were electronically searched in MEDLINE (1950-2012) and EMBASE (1950-2012). Identified titles and abstracts were independently screened by three reviewers to determine eligibility for additional review. We included English articles that reported original data from clinical trials or observational studies on ALF patients.

RESULTS

A total of 103 studies were included. Of these studies 87 used 41 different ALF definitions and the remaining 16 studies did not report any explicit ALF definition. Four components underlying ALF definitions accounted for the differences: presence and/or grading of hepatic encephalopathy (HE); the interval between onset of disease and occurrence of HE; presence of coagulopathy and pre-existing liver disease.

CONCLUSIONS

The diversity in acute liver failure definitions hinders comparability and quantitative analysis among studies. There is room for improvement in the reporting of acute liver failure definitions in prognostic studies. The result of this review may be useful as a starting point to create a uniform acute liver failure definition.

A new treatment strategy for acute liver failure

Acute liver failure (ALF) is a syndrome defined by coagulopathy and encephalopathy and no effective treatments have been established, except for liver transplantation. However, considering the limited supply of donors, we should endeavor to prevent the progression of this syndrome in its early stage to improve the prognosis of patients with ALF. Recently, several authors have reported that over-activation of intrahepatic macrophages plays an important role in the progression of ALF and we have developed a new treatment method, transcatheter arterial steroid injection therapy (TASIT), to suppress macrophage activation. We have now used TASIT for 5 years and have found that TASIT is effective for patients with over-activation of macrophages in the liver but not for those with lesser activation of macrophages. Therefore, to identify the most appropriate patients for TASIT, we tried to categorize patients with ALF or acute liver injury according to markers for the degree of intrahepatic macrophage activation. This approach was helpful to select the appropriate treatment including liver transplantation. We believe that it is essential to analyze disease progression in each patient before selecting the most appropriate treatment.

Meta-analysis of performance of Kings's College Hospital Criteria in prediction of outcome in non-paracetamol-induced acute liver failure

BACKGROUND & AIMS

Current techniques for predicting outcome and requirement for emergency liver transplantation (ELT) in acute liver failure (ALF) are imperfect, though The Kings College Criteria (KCC) are the most commonly applied tools for this purpose. Their performance in identification of patients with non-paracetamol-induced ALF (non-POD ALF), who would not survive without ELT, has recently been questioned. Using quantitative techniques, we therefore performed a meta-analysis of outcome data of the KCC for prediction of survival in non-POD ALF.

METHODS

A systematic database search was performed and retrieved articles graded according to a pre-agreed pro-forma of methodological quality. Collated data was meta-analysed for summary sensitivity, specificity, diagnostic odds ratio (DOR) and ROC curve analysis. Pre-specified sub-group analysis was performed on the basis of methodological quality, the severity of hepatic encephalopathy (HE) of reported patients, timing of KCC application and exclusion of those who underwent ELT.

RESULTS

Eighteen studies with data on 1105 patients were available for production of 2x2 tables. Summary sensitivity was 68 (95% CI 59-77)%, specificity 82 (75-88)% and DOR 12.6 (6.5-26.1). Heterogeneity was detected in the DOR and related to methodological quality (I(2)=64% for all studies versus 47% for 'good' quality studies) and was lower in studies considering high grade HE or dynamic application of KCC (I(2)=0%). For data where ELT were excluded (13 studies) summary sensitivity was 68 (57-79)%, specificity 81 (72-90)% and DOR 12.2 (4.9-30.1) and a symmetric summary ROC curve was produced. Specificity was highest in studies of patients with high grade HE (93 (80-100)%) and where KCC were applied dynamically through the clinical course (88 (78-97)%). Sensitivity was reduced in studies published post 2005 compared with studies pre 1995 (58 (46-71)% versus 85 (76-82)%).

CONCLUSIONS

KCC for outcome in non-POD ALF have good specificity and more limited sensitivity. There is significant heterogeneity in the published data partially related to methodological quality. KCC perform best in groups with high grade encephalopathy and in historically earlier studies suggesting modern medical management of ALF may modify performance of KCC.

An overview of animal models for investigating the pathogenesis and therapeutic strategies in acute hepatic failure

Acute hepatic failure (AHF) is a severe liver injury accompanied by hepatic encephalopathy which causes multiorgan failure with an extremely high mortality rate, even if intensive care is provided. Management of severe AHF continues to be one of the most challenging problems in clinical medicine. Liver transplantation has been shown to be the most effective therapy, but the procedure is limited by shortage of donor organs. Although a number of clinical trials testing different liver assist devices are under way, these systems alone have no significant effect on patient survival and are only regarded as a useful approach to bridge patients with AHF to liver transplantation. As a result, reproducible experimental animal models resembling the clinical conditions are still needed. The three main approaches used to create an animal model for AHF are: surgical procedures, toxic liver injury and infective procedures. Most common models are based on surgical techniques (total/partial hepatectomy, complete/transient devascularization) or the use of hepatotoxic drugs (acetaminophen, galactosamine, thioacetamide, and others), and very few satisfactory viral models are available. We have recently developed a viral model of AHF by means of the inoculation of rabbits with the virus of rabbit hemorrhagic disease. This model displays biochemical and histological characteristics, and clinical features that resemble those in human AHF. In the present article an overview is given of the most widely used animal models of AHF, and their main advantages and disadvantages are reviewed.

Evaluation of a scoring system for assessing prognosis in pediatric acute liver failure

BACKGROUND & AIMS

Pediatric acute liver failure (PALF) results in death or need for liver transplantation (LT) in up to 50% of patients. A scoring system for predicting death or LT (Liver Injury Units [LIU] score) in PALF was previously derived by our group, and used peak values during hospital admission of total bilirubin, prothrombin time/international normalized ratio, and ammonia as significant predictors of outcome. The aims of this study were to test the predictive value of the LIU score in a subsequent validation set of patients and to derive a hospital admission LIU (aLIU) score predictive of outcome.

METHODS

Data were obtained from 53 children admitted with PALF from 2002 to 2006. Outcome was defined at 16 weeks as alive without LT, death, or LT.

RESULTS

Survival without LT at 16 weeks for each LIU score quartile was 92%, 44%, 60%, and 12%, respectively (P < .001). The receiver operating characteristic C index for predicting death or LT by 4 weeks was 86.3. An admission LIU score was derived using admission total bilirubin and prothrombin time/international normalized ratio. Survival without LT at 16 weeks for each quartile using the aLIU score was 85%, 77%, 69%, and 31% (P = .001). The receiver operating characteristic C index for predicting death or LT by 4 weeks was 83.7.

CONCLUSIONS

The original LIU score is a valid predictor of outcome in PALF. The aLIU score is promising and needs to be validated in subsequent patients.

Aetiology and outcome of acute hepatic failure in Greece: experience of two academic hospital centres

Introduction: In Western countries, the most frequent aetiology of acute liver failure (ALF) is acetaminophen overdose, while in developing countries viral infections [hepatitis A virus and hepatitis B virus (HBV)] predominate. Aim: To evaluate the epidemiology, clinical characteristics, outcome and prognostic factors of survival of patients with ALF in Greece during the last 6 years. Results: A total of 40 patients, 28 females (70%), with a median age of 37.4+/-18.6 years (range: 15-84) with ALF were studied. HBV infection was the cause in 53% of them (compared with 74% from a previous study reported in the early 1980s), drug toxicity in 15% and undetermined in 13%. The overall survival was 57.5%, including 94% with and 15% without liver transplantation. Forty-five per cent of our patients had emergency liver transplantation in European Centers within a median time of 3.3 days (1-9) from admission. The total bilirubin level at admission and the development of infections were found to be significantly associated with poor outcome. Conclusions: Hepatitis B virus still remains the most important cause of ALF in Greece, but shows a significant decrease as compared with studies in the early 1980s. Almost half of our patients needed emergency liver transplantation and had a very good survival rate. The other 15% of the patients presented spontaneous survival only with intensive medical support.

Thermodynamic considerations in solid adsorption of bound solutes for patient support in liver failure

New detoxification modes of treatment for liver failure that use solid adsorbents to remove toxins bound to albumin in the patient bloodstream are entering clinical evaluations, frequently in head-to-head competition. While generally effective in reducing toxin concentration beyond that obtainable by conventional dialysis procedures, the solid adsorbent processes are largely the result of heuristic development. Understanding the principles and limitations inherent in competitive toxin binding, albumin versus solid adsorbent, will enhance the design process and, possibly, improve detoxification performance. An equilibrium thermodynamic analysis is presented for both the molecular adsorbent recirculating system (MARS) and fractionated plasma separation, adsorption, and dialysis system (Prometheus), two advanced systems with distinctly different operating modes but with similar equilibrium limitations. The Prometheus analysis also applies to two newer approaches: sorbent suspension reactor and microsphere-based detoxification system. Primary results from the thermodynamic analysis are that: (i) the solute-albumin binding constant is of minor importance to equilibrium once it exceeds about 10(5) L/mol; (ii) the Prometheus approach requires larger solid adsorbent columns than calculated by adsorbent solute capacity alone; and (iii) the albumin-containing recycle stream in the MARS approach is a major reservoir of removed toxin. A survey of published results indicates that MARS is operating under mass transfer control dictated by solute-albumin equilibrium in the recycle stream, and Prometheus is approaching equilibrium limits under current clinical protocols.

Early indicators of prognosis in fulminant hepatic failure: an assessment of the Model for End-Stage Liver Disease (MELD) and King's College Hospital criteria

While King's Hospital Criteria (KCH) criteria are used worldwide, the Model for End-Stage Liver Disease (MELD) is a more recently developed scoring system that has been validated as an independent predictor of patient survival in conditions for liver transplantation (LT). The aim of the present study was to compare MELD and KCH criteria with other early clinical prognostic indicators (CPI) in a cohort of patients with fulminant hepatic failure (FHF). A total of 144 patients (mean age 31.7 +/- 14.7 yr; range 12-82 yr; 62 males) with FHF due to acute viral hepatitis were included into the study. Variables found significant on univariate analysis were entered into a multivariate logistic regression analysis. A total of 52 (36.1%) patients survived, the remaining 92 (63.9%) died. Univariate analysis showed that age, duration of jaundice, jaundice-encephalopathy interval (JEI), grade of encephalopathy, presence of cerebral edema, bilirubin, prothrombin time, creatinine, and MELD score were significantly different between survivors and nonsurvivors. Multivariate logistic regression identified 6 independent CPI of adverse outcome on admission: age >or=50 yr, JEI >7 days, grade 3 or 4 encephalopathy, presence of cerebral edema, prothrombin time >or=35 seconds, and creatinine >or=1.5 mg/dL. Presence of any 3 of 6 CPI was optimum in identifying survivors and nonsurvivors. A MELD score of >or=33 was found to be best discriminant between survivors and nonsurvivors by the construction of receiver operating characteristic (ROC) curves. Any 3 CPI were superior to MELD and KCH criteria in predicting the outcome (c-statistic [95% confidence interval]: CPI 0.802 [0.726-0.878], MELD 0.717 [0.636-0.789], and KCH criteria 0.676 (0.588-0.764); P values: CPI vs. MELD 0.045, CPI vs. KCH criteria 0.019, and MELD vs. KCH criteria 0.472). In conclusion, MELD and KCH criteria are not as useful as a combination of other early CPI in predicting adverse outcome in patients with FHF due to acute viral hepatitis.

MELD score to predict outcome in adult patients with non-acetaminophen-induced acute liver failure

AIMS/BACKGROUND

A model for end stage liver disease (MELD) score >30 was proposed as an excellent predictor of mortality in patients with non-acetaminophen-induced acute liver failure (ALF). We analyzed the prognostic value of MELD score in our patients with ALF who were prospectively registered in our database since 1990.

METHODS

Overall, 106 patients met the criteria of ALF. Excluding seven patients with acetaminophen etiology, 99 patients (42+/-15 years, 40M/59F) were studied.

RESULTS

Causes were cryptogenic (n=38), viral (n=29), drugs (n=20) and miscellaneous (n=12). Of these, 37% (n=37) survived with medical management alone (group I), 16% (n=16) died (group II) and 46% (n=46) underwent liver transplantation (group III). The strongest predictors of poor outcome were advanced encephalopathy, cryptogenic/drug-induced/hepatitis B etiology and a high MELD score. At the time of diagnosis, King's College Hospital criteria and MELD score >30 had similar high negative predictive value (92% and 91%, respectively) and low positive predictive value (52% and 56%, respectively). The predictive values improved only slightly during follow-up. The best cut-off point for MELD score to discriminate between survivors and nonsurvivors was >35, with a sensitivity and specificity of 86% and 75%, respectively.

CONCLUSIONS

MELD score, which mostly takes into consideration the degree of liver impairment, has a similar prognostic value as King's College Hospital criteria to predict outcome in adult patients with nonacetaminophen-induced ALF. Overall, all current scores miss accuracy and therefore there is a clear need for factors that can better predict the regeneration of the liver in this setting.

Clinical heterogeneity in autoimmune acute liver failure

AIM

To describe the outcome and prognosis in a cohort of patients with acute liver failure due to autoimmune hepatitis without liver transplantation.

METHODS

A retrospective trial was conducted in 11 patients with acute liver failure due to autoimmune hepatitis who attended the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. Demographic, biochemical and severity indexes, and treatment and outcome were assessed.

RESULTS

Among the 11 patients, with a median age of 31 years, 72% had inflammatory response syndrome, and six patients received corticosteroids. The mortality rate within four weeks was 56%, and the one-year survival was 27%. In the survivors, severity indexes were lower and 83% received corticosteroids.

CONCLUSION

We observed a relatively high survival rate in patients with acute liver failure due to autoimmune hepatitis. This survival rate could be influenced by severity of the disease and/or use of corticosteroids.