Liver fibrosis

Liver fibrosis is the excessive accumulation of extracellular matrix proteins including collagen that occurs in most types of chronic liver diseases. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension and often requires liver transplantation. Our knowledge of the cellular and molecular mechanisms of liver fibrosis has greatly advanced. Activated hepatic stellate cells, portal fibroblasts, and myofibroblasts of bone marrow origin have been identified as major collagen-producing cells in the injured liver. These cells are activated by fibrogenic cytokines such as TGF-beta1, angiotensin II, and leptin. Reversibility of advanced liver fibrosis in patients has been recently documented, which has stimulated researchers to develop antifibrotic drugs. Emerging antifibrotic therapies are aimed at inhibiting the accumulation of fibrogenic cells and/or preventing the deposition of extracellular matrix proteins. Although many therapeutic interventions are effective in experimental models of liver fibrosis, their efficacy and safety in humans is unknown. This review summarizes recent progress in the study of the pathogenesis and diagnosis of liver fibrosis and discusses current antifibrotic strategies.

A model to predict survival in patients with end-stage liver disease

A recent mandate emphasizes severity of liver disease to determine priorities in allocating organs for liver transplantation and necessitates a disease severity index based on generalizable, verifiable, and easily obtained variables. The aim of the study was to examine the generalizability of a model previously created to estimate survival of patients undergoing the transjugular intrahepatic portosystemic shunt (TIPS) procedure in patient groups with a broader range of disease severity and etiology. The Model for End-Stage Liver Disease (MELD) consists of serum bilirubin and creatinine levels, International Normalized Ratio (INR) for prothrombin time, and etiology of liver disease. The model's validity was tested in 4 independent data sets, including (1) patients hospitalized for hepatic decompensation (referred to as "hospitalized" patients), (2) ambulatory patients with noncholestatic cirrhosis, (3) patients with primary biliary cirrhosis (PBC), and (4) unselected patients from the 1980s with cirrhosis (referred to as "historical" patients). In these patients, the model's ability to classify patients according to their risk of death was examined using the concordance (c)-statistic. The MELD scale performed well in predicting death within 3 months with a c-statistic of (1) 0.87 for hospitalized patients, (2) 0.80 for noncholestatic ambulatory patients, (3) 0.87 for PBC patients, and (4) 0.78 for historical cirrhotic patients. Individual complications of portal hypertension had minimal impact on the model's prediction (range of improvement in c-statistic: <.01 for spontaneous bacterial peritonitis and variceal hemorrhage to ascites: 0.01-0.03). The MELD scale is a reliable measure of mortality risk in patients with end-stage liver disease and suitable for use as a disease severity index to determine organ allocation priorities.

Cerebral herniation in patients with acute liver failure is correlated with arterial ammonia concentration

Cerebral edema leading to cerebral herniation (CH) is a common cause of death in acute liver failure (ALF). Animal studies have related ammonia with this complication. During liver failure, hepatic ammonia removal can be expected to determine the arterial ammonia level. In patients with ALF, we examined the hypotheses that high arterial ammonia is related to later death by CH, and that impaired removal in the hepatic circulation is related to high arterial ammonia. Twenty-two patients with ALF were studied retrospectively. In addition, prospective studies with liver vein catheterization were performed after development of hepatic encephalopathy (HE) in 22 patients with ALF and 9 with acute on chronic liver disease (AOCLD). Cerebral arterial-venous ammonia difference was studied in 13 patients with ALF. In all patients with ALF (n = 44), those who developed CH (n = 14) had higher arterial plasma ammonia than the non-CH (n = 30) patients (230 +/- 58 vs. 118 +/- 48 micromol/L; P <. 001). In contrast, galactose elimination capacity, bilirubin, creatinine, and prothrombin time were not different (NS). Cerebral arterial-venous differences increased with increasing arterial ammonia (P <.001). Arterial plasma ammonia was lower than hepatic venous in ALF (148 +/- 73 vs. 203 +/- 108 micromol/L; P <.001). In contrast, arterial plasma ammonia was higher than hepatic venous in patients with AOCLD (91 +/- 26 vs. 66 +/- 18 micromol/L; P <.05). Net ammonia release from the hepatic-splanchnic region was 6.5 +/- 6. 4 mmol/h in ALF, and arterial ammonia increased with increasing release. In contrast, there was a net hepatic-splanchnic removal of ammonia (2.8 +/- 3.3 mmol/h) in patients with AOCLD. We interpret these data that in ALF in humans, vast amounts of ammonia escape hepatic metabolism, leading to high arterial ammonia concentrations, which in turn is associated with increased cerebral ammonia uptake and CH.

Serum sodium predicts mortality in patients listed for liver transplantation

With the implementation of the model for end-stage liver disease (MELD), refractory ascites, a known predictor of mortality in cirrhosis, was removed as a criterion for liver allocation. Because ascites is associated with low serum sodium, we evaluated serum sodium as an independent predictor of mortality in patients with cirrhosis who were listed for liver transplantation and whether the addition of serum sodium to MELD was superior to MELD alone. This is a single-center retrospective cohort of all adult patients with cirrhosis listed for transplantation from February 27, 2002, to December 26, 2003. Listing laboratories were those nearest the listing date +/-2 months. Of the 513 patients meeting inclusion criteria, 341 were still listed, while 172 were removed from the list (105 for transplantation, 56 for death, 11 for other reasons). The median serum sodium and MELD scores were 137 mEq/L (range, 110-155) and 15 (range, 6-51), respectively, at listing. Median follow-up was 201 (range, 1-662) days. The risk of death with serum sodium <126 mEq/L at listing or while listed was increased, with hazard ratios of 7.8 (P < .001) and 6.3 (P < .001), respectively, and the association was independent of MELD. The c-statistics of receiver operating characteristic curves for predicting mortality at 3 months based upon listing MELD with and without listing serum sodium were 0.883 and 0.897, respectively, and at 6 months were 0.871 and 0.905, respectively. In conclusion, serum sodium <126 mEq/L at listing or while listed for transplantation is a strong independent predictor of mortality. Addition of serum sodium to MELD increases the ability to predict 3- and 6-month mortality in patients with cirrhosis.

Model for end stage liver disease score predicts mortality across a broad spectrum of liver disease

BACKGROUND/AIMS

The utility of the model for end stage liver disease (MELD) score in non-transplant patients, particularly in those with less severe chronic liver disease remains uncertain. We studied and compared the predictive abilities of the MELD score and the Child-Turcotte-Pugh (CTP) score for intermediate (1-year) and long-term (5-year) mortality.

METHODS

One thousand six hundred and eleven patients with chronic liver disease were studied. Observed and predicted survival curves were plotted to evaluate the predictive ability of the MELD score for survival. Receiver operating characteristic (ROC) curves was used to compare the MELD and CTP score. A multivariable model was constructed to examine predictors of mortality.

RESULTS

The MELD score was a good predictor of 1-year mortality in chronic liver disease (c-statistics for all subgroups >/=0.75) and of 3- and 6-month mortality in alcoholic hepatitis (c-statistic >/=0.83). The CTP score had similar predictive abilities as the MELD. Hepatic encephalopathy was a strong independent predictor of death (Hazard ratio-2.8, P<0.0001).

CONCLUSIONS

The MELD score is a valid prognostic score for intermediate term mortality in a heterogeneous population with chronic liver disease although the CTP score is equivalent in predicting survival. Inclusion of hepatic encephalopathy adds additional prognostic value to the MELD score.

Pathophysiological effects of albumin dialysis in acute-on-chronic liver failure: a randomized controlled study

The pathophysiological basis of acute-on-chronic liver failure (ACLF) is unclear but systemic inflammatory response is thought to be important. In patients with ACLF, the molecular adsorbents recirculating system (MARS) improves individual organ function, but the effect of MARS on the proposed mediators of systemic inflammatory response is unclear. The present study was designed to determine the effect of MARS on the cytokine profile, oxidative stress, nitric oxide, and ammonia. A total of 18 patients with alcohol-related ACLF due to inflammation-related precipitants were randomized to receive standard medical therapy (SMT) alone, or with MARS therapy over 7 days. Plasma cytokines, malondialdehyde (MDA), free radical production, nitrate / nitrite (NOx), and ammonia were measured. Encephalopathy improved significantly with MARS (P < .01), but not with SMT. Mean arterial pressure and renal function remained unchanged. No significant change of plasma cytokines and ammonia levels were observed in either group. Plasma MDA levels did not change either. There was a fall in NOx (P < .05) with MARS, but not with SMT. In conclusion, in inflammation-related ACLF patients, albumin dialysis using MARS results in improvement of encephalopathy, independent of changes of ammonia or cytokines, without improving blood pressure or renal function. These results should temper the liberal use of MARS until further data is available.

MELD and other factors associated with survival after liver transplantation

Allocation of cadaveric livers for transplantation in the United States is now based on the severity of illness as determined by the model for end-stage liver disease (MELD) score, a function of bilirubin, creatinine and international normalized ratio (INR). The aim of our study was to determine the association of various pre-transplant risk factors, including the MELD score, on patient survival after orthotopic liver transplantation (OLT). The medical records of 499 consecutive patients (233 female, 266 males, mean age 50.9 +/- 10.6 years) undergoing cadaveric OLT at our institution between June 1990 and February 1998 were reviewed. In the 407 patients alive at the latest contact, follow-up was 4.7 years, with a minimum of 20 months (maximum of 9.4 years). Variables considered for analysis included MELD score, age, pre-transplant renal dysfunction requiring dialysis, Child-Pugh classification, underlying liver disease, diabetes mellitus, and heart disease (ischemic/valvular/other). There were 92 deaths during follow-up. In univariate analysis, the MELD score, renal failure requiring hemodialysis pre-OLT, age > 42 years, and underlying etiology of liver disease were significantly associated with death during long-term follow-up. In multivariate models, age, underlying etiology of liver disease and renal failure requiring hemodialysis were independent predictors of death after OLT.

Influence of hepatic venous pressure gradient on the prediction of survival of patients with cirrhosis in the MELD Era

Measurements of portal pressure, usually obtained via the hepatic venous pressure gradient (HVPG) may be a prognostic marker in cirrhosis. The aim of this study was to evaluate the impact of HVPG on survival in patients with cirrhosis in addition to the Model for End-Stage Liver Disease (MELD) score. We also examined whether inclusion of HVPG in a model with MELD variables improves its prognostic ability. Retrospective analyses of all patients who had HVPG measurements between January 1998 and December 2002 were considered. Proportional hazards Cox models were developed. Prognostic calibrative and discriminative ability of the model was evaluated. In this period, 693 patients had a hepatic hemodynamic study, and 393 patients were included. Survival was significantly worse in those patients with greater HVPG value (univariate HR, 1.05; 95% CI, 1.02-1.08; P = .001). HVPG remained as an independent variable in a model adjusted by MELD, ascites, encephalopathy, and age (multivariate HR, 1.03; 95% CI, 1.00-1.06; P = .05) so that each 1-mmHg increase in HVPG had a 3% increase in death risk. In addition, HVPG as well as MELD score variables and age, significantly contributes to the calibrative predictive capacity of the prognostic model; however, discriminative ability improved only slightly (overall C statistic [95% CI]; MELD score variables: 0.71 [0.62-0.80], MELD score variables, age, and HVPG 0.76: [0.69-0.83]). In conclusion, HVPG has an independent effect on survival in addition to the MELD score. Although inclusion of HVPG and age in a survival predicting model would improve the calibrative ability of MELD, its discriminative ability is not significantly improved.

A correlation between the pretransplantation MELD score and mortality in the first two years after liver transplantation

The Model for End-Stage Liver Disease (MELD) score is now the criteria for allocation in liver transplantation for patients with chronic disease. Although the score has been effective in the prediction of mortality in patients awaiting liver transplantation, its abilities to predict posttransplantation outcome need study. The aim of this study is to compare outcome in the first 2 years after liver transplantation according to the pretransplantation MELD score. The study includes 669 consecutive patients who underwent primary liver transplantation between December 1993 and October 1999 in a single transplant center. Patients who died of malignancy were excluded from the series. Pretransplantation MELD score was calculated using the United Network for Organ Sharing formula. Patients were stratified according to MELD score less than 15, 15 to 24, and 25 and higher. Posttransplantation survival at 3, 6, 12, 18, and 24 months was significantly lower in the groups with a higher MELD score. The difference was significant for hepatitis C and noncholestatic liver diseases, but not cholestatic diseases. In patients with a MELD score between 15 and 24, survival was significantly greater with cholestatic diseases and lower in patients with hepatitis C. In our study, pretransplantation MELD score correlates with survival in the first 2 years after transplantation. There is a survival advantage for patients with cholestatic diseases compared with those with hepatitis C. These findings suggest the need to readjust MELD score-based allocation decisions to consider patient outcome.

Etoposide prevents apoptosis in mouse liver with D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure resulting in reduction of lethality

D-Galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver injury is an experimental model of fulminant hepatic failure in which tumor necrosis factor alpha (TNF-alpha) plays a pivotal role. We examined the effects of etoposide on GalN/LPS-induced fulminant hepatic failure. Mice were given an intraperitoneal dose of GalN (800 microg/g body weight)/LPS (100 ng/g body weight) with and without intraperitoneal etoposide (10 microg/g body weight) treatment. Liver injury was assessed biochemically and histologically. TNF-alpha levels in the serum, and apoptosis of hepatocytes and CPP32/caspase-3 in the liver, were determined. GalN/LPS treatment caused lethal liver injury in 87% of animals (13 of 15). The effect was associated with significant increases in TNF-alpha and alanine transaminase (ALT) levels in serum, the number of apoptotic hepatocytes, CPP32/caspase-3 activity, and TNF receptor 1 (TNFR1) mRNA expression in the liver. Etoposide (10 microg/g body weight) was given 3 times (at 50, 26, and 4 hours before GalN/LPS administration). Treatment of GalN/LPS-treated mice with etoposide reduced apoptosis of hepatocytes, resulting in reduction of lethality (13% [2 of 15]), while another topoisomerase II inhibitor, IRCF-193, showed no significant effect. The antilethal effect of etoposide was also confirmed in GalN/TNF-alpha-induced fulminant hepatic failure. Etoposide treatment reduced CPP32/caspase-3 activity in the liver, although it did not alter the serum TNF-alpha levels or hepatic TNFR1 mRNA expressions. In addition, etoposide treatment enhanced the mRNA and protein expression of Bcl-xL, an antiapoptotic molecule in the liver. The present findings suggest that etoposide prevents endotoxin-induced lethal liver injury by up-regulation of Bcl-xL, and that etoposide could be useful for the treatment of TNF-alpha-mediated liver diseases.

Liver dysfunction in sepsis

Despite continuous progress in medicine, sepsis remains the main cause of deaths in the intensive care unit. Liver failure complicating sepsis/septic shock has a significant impact on mortality in this group of patients. The pathophysiology of sepsis-associated liver dysfunction is very complicated and still not well understood. According to the Surviving Sepsis Campaign (SSC) Guidelines, the diagnosis of liver dysfunction during sepsis is based on the increase in bilirubin concentration >2 mg/dL and the occurrence of coagulation disorders with INR > 1.5. The lack of specificity and ability to distinguish acute liver failure from previous liver dysfunction disqualifies bilirubin as a single parameter reflecting the complex liver function. Clinical manifestations of sepsis-associated liver dysfunction include hypoxic hepatitis, sepsis-induced cholestasis and dysfunction of protein synthesis manifesting with, e.g., coagulopathies. Detoxifying liver dysfunction, which is associated with an increase in serum ammonia concentration, manifesting with e.g., confusion, loss of consciousness and hepatic encephalopathy, may be disguised by analgosedation used in the intensive care unit. To determine a liver dysfunction in a critically ill patient, the concept of shock liver may be used. It is a complex syndrome of hemodynamic, cellular, molecular and immunologic changes leading to severe liver hypoxia. In clinical practice, there is no standardized diagnostic panel that would allow for an early, clear diagnosis of acute liver dysfunction, and there is no therapeutic panel enabling the full restoration of damaged liver function. The aim of the article is to present the pathophysiology and clinical manifestations of sepsis-associated liver dysfunction.

Interleukin 6/gp130-dependent pathways are protective during chronic liver diseases

The contribution of the acute phase inducer interleukin 6 (IL-6) in the pathogenesis of liver diseases is yet unclear. Our analysis showed enhanced expression of IL-6 in livers derived from patients with acute and chronic liver diseases. Additionally, IL-6 plasma levels were significantly increased in patients with chronic liver diseases and showed an inverse correlation with biochemical markers of liver function and a positive correlation with inflammatory markers, signs of portal hypertension, and the degree of liver fibrosis. To prove the relevance of these clinical findings, we applied the tetrachlorcarbonide (CCl(4)) model to conditional knockout animals (Cre/loxP system) for gp130, the common signal transducer of IL-6 family cytokines. Cre recombinases were expressed through a hepatocyte (AlfpCre) and a ubiquitous (MxCre) control element. Gp130 deleted mice had a totally abolished STAT3 activation and acute phase response induction, but gp130 deletion had no effect on the degree of acute liver injury and subsequent hepatocyte proliferation. In contrast, during chronic liver injury induced by biweekly application of CCl(4), deletion of the gp130 receptor in nonparenchymal liver cells and not hepatocytes resulted in fibrosis progression. In conclusion, our experiments indicate an involvement of IL-6 in the pathogenesis of liver diseases and suggest a protective role of IL-6/gp130-dependent pathways in nonparenchymal liver cells during fibrosis progression in chronic liver diseases. (Hepatology 2003;38:218-229).

Summary report of a national conference: Evolving concepts in liver allocation in the MELD and PELD era. December 8, 2003, Washington, DC, USA

A national conference was held to review and assess data gathered since implementation of MELD and PELD and determine future directions. The objectives of the conference were to review the current system of liver allocation with a critical analysis of its strengths and weaknesses. Conference participants used an evidence-based approach to consider whether predicted outcome after transplantation should influence allocation, to discuss the concept of minimal listing score, to revisit current and potential expansion of exception criteria, and to determine whether specific scores should be used for automatic removal of patients on the waiting list. After review of data from the first 18 months since implementation, association and society leaders, and surgeons and hepatologists with wide regional representation were invited to participate in small group discussions focusing on each of the main objectives. At the completion of the meeting, there was agreement that MELD has had a successful initial implementation, meeting the goal of providing a system of allocation that emphasizes the urgency of the candidate while diminishing the reliance on waiting time, and that it has proven to be a powerful tool for auditing the liver allocation system. It was also agreed that the data regarding the accuracy of PELD as a predictor of pretransplant mortality were less conclusive and that PELD should be considered in isolation. Recommendations for the transplant community, based on the analysis of the MELD data, were discussed and are presented in the summary document.

Utility of standard nutritional parameters in detecting body cell mass depletion in patients with end-stage liver disease

Protein-calorie malnutrition, best measured by body cell mass (BCM) depletion, has been associated with adverse outcomes in patients with end-stage liver disease. We prospectively measured BCM and multiple standard nutritional parameters in patients with end-stage liver disease to determine which, if any, of the traditionally measured nutritional parameters correlate with BCM. A detailed nutritional assessment, including BCM analysis, subjective global assessment, anthropometry, handgrip dynamometry, laboratory tests, and body composition measured by dual-energy X-ray absorptiometry was performed in 69 sequential patients awaiting liver transplantation. The frequency of abnormalities of specific parameters of nutritional status varied between 19% and 99%. Most of the commonly measured parameters of nutritional status correlated poorly with BCM. Patients with depleted BCM (lowest quartile for sex) had midarm circumference (P <.01), arm-muscle circumference (P <.001), handgrip strength (P <.001), blood urea nitrogen (P <.01), and creatinine (P <.01) values less than those for patients with greater BCM (highest 3 quartiles for sex). In multivariate analysis, arm-muscle circumference and handgrip strength were the best predictors of BCM. The combined criteria of handgrip strength less than 30 kg and arm-muscle circumference less than 23 cm have a sensitivity of 94% and a negative predictive value of 97% in identifying patients with depleted BCM. Although abnormalities of nutritional parameters are highly prevalent among patients with end-stage liver disease, most parameters of nutritional status do not correlate with BCM. In patients with end-stage liver disease, arm-muscle circumference and handgrip strength are the most sensitive markers of BCM depletion.

Evaluation of the increase in model for end-stage liver disease (DeltaMELD) score over time as a prognostic predictor in patients with advanced cirrhosis: risk factor analysis and comparison with initial MELD and Child-Turcotte-Pugh score

BACKGROUND/AIMS

The model for end-stage liver disease (MELD) has been used to prioritize cirrhotic patients awaiting liver transplantation. The change in MELD score over time (DeltaMELD) may have additional prognostic value. We investigated the ability of DeltaMELD to predict the outcome of advanced cirrhosis and prospectively assessed the factors associated with increasing DeltaMELD.

METHODS

Risk factors were determined in 58 prospectively followed-up patients. The predictive power of DeltaMELD, initial MELD and Child-Turcotte-Pugh (CTP) score was compared by using c-statistic in 351 patients.

RESULTS

Ascites (P=0.020) and hepatic encephalopathy (P=0.023) were significantly associated with increasing MELD score at 3 months. The area under receiver operating characteristic (ROC) curve for DeltaMELD/month was 0.779 compared with 0.718 for MELD (P=0.130) and 0.528 for CTP score (P<0.001) at 6 months; the area was 0.822, 0.744 and 0.528, respectively (P=0.018 and <0.001, respectively) at 12 months. DeltaMELD/month >2.5 was the only significant prognostic predictor at 6 (odds ratio: 9.8, P<0.001) and 12 months (odds ratio: 16.3, P<0.001) in multivariate logistic analysis.

CONCLUSIONS

Increasing MELD score is associated with the onset of ascites and encephalopathy. DeltaMELD is superior to initial MELD and CTP scores to predict intermediate term outcome in patients with advanced cirrhosis.

Alcohol use after liver transplantation in alcoholics: a clinical cohort follow-up study

The purposes of this study were to determine among a cohort of long-term alcoholic survivors after liver transplantation (1) the incidence of alcohol use, (2) its effect on allograft integrity and extrahepatic health, and (3) the validity of the pretransplant alcohol prognosis screening process. Retrospective clinical cohort study of all alcoholic patients undergoing orthotopic liver transplantation at a single center from February 1987 until January 1991 with follow-up through December 1994, giving a median duration of follow-up of 63 months (range, 6-89 months). Multidisciplinary liver transplantation program at a tertiary-care academic medical center. Fifty alcoholic, long-term liver transplant recipients. The frequency of alcohol relapse, defined as any alcohol use in the period after transplantation, was determined by two questionnaire studies and by clinical follow-up. Allograft integrity was assessed by coded review of serial percutaneous allograft biopsies. Potential systemic effects of alcohol relapse were assessed by chart review. The alcohol prognosis screening process was evaluated by retrospectively comparing pretransplant estimates of putative indicators of alcoholism prognosis in posttransplant alcohol users and abstainers. Thirty-three recipients (66%) consistently denied any alcohol use throughout the duration of posttransplant follow-up, whereas 17 (34%) were identified as having consumed alcohol at least once since the transplant. There were no significant differences at the time of evaluation between abstainers and alcohol users in age, sex distribution, severity of liver dysfunction, median duration of abstinence, or University of Michigan alcoholism prognosis score. The median interval from transplantation to alcohol relapse was 17 months, with a range of 3 to 45 months. Recurrent alcohol use was associated with significant medical complications sufficient to require admission to the hospital in 6 patients. One patient died of graft dysfunction, noncompliance with immunosuppressant medications, and presumed graft rejection while drinking. Mild or progressive hepatitis, which was the most common abnormality in posttransplant liver biopsy findings, was equally distributed between both alcohol users and abstainers and sometimes occurred in the absence of antibody to hepatitis C virus antibodies. There was a similar frequency of biopsy-proven acute cellular rejection in alcohol users and abstainers. Typical histological features of alcoholic liver injury were present in posttransplant biopsies from 1 alcohol user only. Alcohol use by alcoholics is uncommon in the first 5 years after liver transplantation, and alcohol-associated liver injury is unusual. Mild nonspecific hepatitis is common in both alcohol users and nonusers alike. Among a small subset of alcoholic transplant recipients, drinking behavior after liver transplantation is associated with considerable morbidity, requiring hospital admissions and occasionally leading to graft loss and death.

Fulminant hepatic failure: outcome after listing for highly urgent liver transplantation-12 years experience in the nordic countries

Fulminant hepatic failure is a common indication for liver transplantation. Outcomes of patients listed for a highly urgent liver transplantation have been studied, with special emphasis on etiology of the liver disease, clinical condition, and ABO blood type. Data have been collected from the Nordic Liver Transplantation Registry. All Nordic patients listed for a highly urgent primary liver transplantation during a 12-year period have been included. Of the 315 patients listed for a highly urgent liver transplantation, 229 (73%) received a first liver allograft, 50 patients (16%) died without transplantation, and 36 patients (11%) were permanently withdrawn and survived. In 43% of the patients, no definite etiology of the liver failure could be established. Paracetamol intoxication was the most frequent specific indication for listing. Patients with blood type A had no significant shorter waiting time (3.8 v 6.6 days; P =.1) but a higher rate of transplantation (82% v 66%, P =.006) as compared with blood type O patients. In a multivariate analysis, paracetamol intoxication remained the single independent predictor of an outcome without transplantation. In conclusion, a high transplantation rate was observed among patients listed for a highly urgent liver transplantation because of fulminant hepatic failure. Blood type O patients had a lower chance of receiving a liver allograft. Patients with paracetamol intoxication had both a higher mortality without transplantation and a higher withdrawal rate attributable to improved condition.

Hemodynamic changes during a single treatment with the molecular adsorbents recirculating system in patients with acute-on-chronic liver failure

The aim of this pilot study is to evaluate the circulatory safety of treatment with the molecular adsorbents recirculating system (MARS) by determining the effect on systemic hemodynamics of a single MARS treatment in patients with acute-on-chronic liver failure (AOCLF). In eight patients admitted with AOCLF, a single 10-hour MARS treatment was performed. Systemic hemodynamic variables were determined before and during treatment. Bilirubin and urea were monitored as measures of protein-bound and water-soluble toxins. During MARS treatment, mean arterial pressure increased from 67 +/- 9 to 76 +/- 6 mm Hg (P < .05). Systemic vascular resistance index increased from 757 +/- 134 to 884 +/- 183 dyne x s/cm(5)/m(2) (P < .05), whereas cardiac index remained constant (5.9 +/- 0.7 v 6.0 +/- 1.1 L/min/m(2)). No episode of dialysis-induced hypotension was observed. Systemic oxygen consumption remained constant (92 +/- 30 v 93 +/- 11 mL/min/m(2)). Bilirubin levels decreased from 537 +/- 192 to 351 +/- 106 micromol/L (P < .05), and urea levels, from 19.1 +/- 13.9 to 6.7 +/- 5.1 mmol/L (P < .05). In conclusion, MARS treatment proved safe in critically ill patients with no attributing side effects.

The role of cytokines in liver failure and regeneration: potential new molecular therapies

The liver is a unique organ, and first in line, the hepatocytes encounter the potential to proliferate during cell mass loss. This phenomenon is tightly controlled and resembles in some way the embryonal co-inhabitant cell lineage of the liver, the embryonic hematopoietic system. Interestingly, both the liver and hematopoietic cell proliferation and growth are controlled by various growth factors and cytokines. IL-6 and its signaling cascade inside the cells through STAT3 are both significantly important for liver regeneration as well as for hematopoietic cell proliferation. The process of liver regeneration is very complex and is dependent on the etiology and extent of liver damage and the genetic background. In this review we will initially describe the clinical relevant condition, portraying a number of available animal models with an emphasis on the relevance of each one to the human condition of fulminant hepatic failure (FHF). The discussion will then be focused on the role of cytokines in liver failure and regeneration, and suggest potential new therapeutic modalities for FHF. The recent findings on the role of IL-6 in liver regeneration and the activity of the designer IL-6/sIL-6R fusion protein, hyper-IL-6, in particular, suggest that this molecule could significantly enhance liver regeneration in humans, and as such could be a useful treatment for FHF in patients.

Improved physical performance after orthotopic liver transplantation

Orthotopic liver transplantation (OLT) has become a frequently used treatment for end-stage liver disease and acute liver failure, and liver function is markedly improved after transplantation. However, no studies have investigated the development in physical capacity after OLT. On this basis, the aim of the present study is to study the influence of OLT on physical fitness during the first postoperative year. Twenty-three men with a mean age of 45.1 years (range, 24 to 62 years) and 15 women with a mean age of 44.6 years (range, 21 to 62 years) were included in the study. Preoperative maximal oxygen uptake (VO2max) during graded ergometer bicycling, isokinetic knee extension/flexion moments, and functional performance (i.e., 6-minute walking distance and standardized transfers and squats) was measured. Preoperative fitness and strength was 40% to 50% less than expected in the age-matched general population. Post-OLT, all patients underwent a supervised exercise program for 8 to 24 weeks. Follow-up data showed a significant increase in all tested physical performance parameters after OLT. Six months post-OLT, VO2max had increased 43%; knee strength, 60% to 100%; and functional performance, 22% to 27%. One year postsurgery, general health was improved and perceived as excellent or good in all patients. All patients were independent in activities of daily living, and the level of physical activity increased after OLT. No further improvement in either physical performance parameters or self-assessed parameters was seen beyond 6 months after OLT. In conclusion, these findings indicate that OLT combined with a supervised post-OLT exercise program improves physical fitness, muscle strength, and functional performance in individuals with chronic liver disease.

MELD scores of liver transplant recipients according to size of waiting list: impact of organ allocation and patient outcomes

CONTEXT

The Model for Endstage Liver Disease (MELD) score serves as the basis for the distribution of deceased-donor (DD) livers and was developed in response to "the final rule" mandate, whose stated principle is to allocate livers according to a patient's medical need, with less emphasis on keeping organs in the local procurement area. However, in selected areas of the United States, organs are kept in organ procurement organizations (OPOs) with small waiting lists and transplanted into less-sick patients instead of being allocated to sicker patients in nearby transplant centers in OPOs with large waiting lists.

OBJECTIVE

To determine whether there is a difference in MELD scores for liver transplant recipients receiving transplants in small vs large OPOs.

DESIGN AND SETTING

Retrospective review of the US Scientific Registry of Transplant Recipients between February 28, 2002, and March 31, 2003. Transplant recipients (N = 4798) had end-stage liver disease and received DD livers.

MAIN OUTCOME MEASURES

MELD score distribution (range, 6-40), graft survival, and patient survival for liver transplant recipients in small (<100) and large (> or =100 on the waiting list) OPOs.

RESULTS

The distribution of MELD scores was the same in large and small OPOs; 92% had a MELD score of 18 or less, 7% had a MELD score between 19 and 24, and only 2% of listed patients had a MELD score higher than 24 (P =.85). The proportion of patients receiving transplants in small OPOs and with a MELD score higher than 24 was significantly lower than that in large OPOs (19% vs 49%; P<.001). Patient survival rates at 1 year after transplantation for small OPOs (86.4%) and large OPOs (86.6%) were not statistically different (P =.59), and neither were graft survival rates in small OPOs (80.1%) and large OPOs (81.3%) (P =.80).

CONCLUSIONS

There is a significant disparity in MELD scores in liver transplant recipients in small vs large OPOs; fewer transplant recipients in small OPOs have severe liver disease (MELD score >24). This disparity does not reflect the stated goals of the current allocation policy, which is to distribute livers according to a patient's medical need, with less emphasis on keeping organs in the local procurement area.

Comparison of the use of standard heparin and prostacyclin anticoagulation in spontaneous and pump-driven extracorporeal circuits in patients with combined acute renal and hepatic failure

Although prostacyclin has been reported to be an effective extracorporeal anticoagulant for intermittent haemofiltration and dialysis treatments, it has been suggested that it is inferior to heparin in preventing clotting in spontaneously driven continuous haemofiltration and/or dialysis circuits. We studied the effectiveness of both heparin and prostacyclin as anticoagulants in a variety of extracorporeal circuits in 17 patients with combined acute hepatic and renal failure who were at risk of haemorrhage. Although there were no differences in the pump-assisted extracorporeal circuits, prostacyclin was found superior to heparin during spontaneously driven continuous arteriovenous haemofiltration and/or dialysis. During some 2,600 h of prostacyclin therapy, there were only 3 episodes of haemorrhage that required blood transfusion compared to 8 major haemorrhages and 2 deaths from intracerebral haemorrhage during 600 h of anticoagulation with heparin. The median filter life was greater with prostacyclin, 60 h (42-72), compared to heparin, 8 h (4-16), p < 0.01. This study suggests that prostacyclin is superior to heparin in maintaining the integrity of a spontaneous arteriovenous extracorporeal circuit in patients at risk of major haemorrhage.

Subclinical seizure activity and prophylactic phenytoin infusion in acute liver failure: a controlled clinical trial

Subclinical seizure activity in the patient with encephalopathy and on ventilation with acute liver failure (ALF) is a poorly recognized entity. Its importance lies in the likely exacerbation of cerebral hypoxia and the contribution of such seizure activity to the development of cerebral edema. The aim of the present study was to document the frequency of subclinical seizure activity in a cohort of patients with ALF by using a cerebral function and activity monitor that allows continuous recording of electroencephalogram activity at the bedside and to determine whether the prophylactic administration of the antiepileptic agent phenytoin would reduce its occurrence. Forty-two patients were enrolled in a controlled clinical trial: 20 patients were given phenytoin and 22 acted as controls. Subclinical seizure activity was recorded in 3 and 10 patients, respectively, of the treated and control groups. Pupillary abnormalities indicative of seizure activity and/or raised intracranial pressure (ICP) were also seen less frequently in the phenytoin-treated group compared with the controls (5 and 11 patients, respectively). Autopsy examinations available in 19 patients showed signs of cerebral edema in only 2 (22%) of the phenytoin-treated patients compared with 7 (70%) of the controls (P <.033). Based on these findings, we recommend that patients with ALF, on reaching the stage of grade III or IV encephalopathy, should be routinely monitored for subclinical seizure activity. In this study, prophylaxis with phenytoin reduced the frequency of such seizure activity and its effects, and proved to be safe with the regimen used.