Acute liver failure

The HepatAssist® Bioartificial Liver Support System: clinical study and pig hepatocyte process

Based on perfusion of patient plasma through a circuit incorporating a hollow fibre membrane cartridge containing porcine hepatocytes, a bioartificial support system, or HepatAssist System, has been developed. Thirty-nine patients with acute liver failure (ALF) were treated in a Phase I multicentre clinical study. Thirty-two patients were bridged to orthotopic liver transplantation and six patients recovered without requiring a graft. Patient survival rate at one month was 90%. On the basis of these results, a multicentre Phase II/III, randomised, controlled, parallel group study of the HepatAssist System, compared to standard care in ALF patients has been initiated.

Indication of liver transplantation following amatoxin intoxication

BACKGROUND/AIMS

Indication of liver transplantation in acute liver failure following amatoxin intoxication is still uncertain.

METHODS

One hundred and ninety-eight patients were studied retrospectively. The laboratory parameters alanine-aminotransferase, serum bilirubin, serum creatinine and prothrombin index were analyzed over time. Predictors of fatal outcome and survival were determined by receiver-operating-characteristic and sensitivity-specificity analysis.

RESULTS

Twenty-three patients died in the median 6.1 days (range, 2.7-13.9 days) after ingestion. Using a single parameter as predictor of fatal outcome the area under the receiver-operating-characteristic curve of prothrombin index (0.96) and serum creatinine (0.93) were both significantly greater (P<0.05) compared with serum bilirubin (0.82) and alanine-aminotransferase (0.69). Prediction of fatal outcome had an optimum, if a prothrombin index less than 25% was combined with a serum creatinine greater than 106 micromol/l from day 3 after ingestion onwards (sensitivity 100%, 95% confidence interval 87-100; specificity 98%, 95% confidence interval 94-100). The median time period between the first occurrence of this predictor in non-survivors and death was 63h (range, 3-230h).

CONCLUSIONS

A decision model of liver transplantation following amatoxin intoxication using prothrombin index in combination with serum creatinine from day 3 to 10 after ingestion enables an early and reliable assessment of outcome.

Bridges to transplantation

The definitive treatment of patients with acute liver failure is liver transplantation. Organ Procurement and Transplantation Network status 1 patients receive priority, but the median waiting time in 2002 was 11 days. Patients who are small or have an unusual blood type are expected to wait even longer. Because cerebral edema and death may occur before a liver is available, numerous methods of bridging patients to transplantation by artificial means have been proposed. To date, no system of hepatic support has been proven effective at delaying the onset of cerebral edema in controlled trials.

Value of albumin dialysis therapy in severe liver insufficiency

A blood purification system, molecular adsorbents re-circulating system (MARS), is based on the removal of both protein-bound and water-soluble substances and toxins in the liver. We treated a total of 88 patients within 2 years. Of these patients, 45 had acute liver failure (ALF), 31 had acute decompensation of chronic liver disease, eight had graft failure and four had miscellaneous conditions. Of the patients with ALF, 80% survived; in 23 patients their own liver recovered and 13 patients underwent successful transplantation. Only 23% of patients with acute-on-chronic liver failure survived. Most of them were not considered for transplantation due to their having liver failure from alcoholism and from not abstaining from drinking. MARS is a promising therapy for ALF, allowing the patient's own liver to recover or allowing enough time to find a liver graft. Best results were achieved in patients who had been intoxicated with a lethal dose of toxin. On the other hand, we did not observe much benefit in patients with severe acute-on-chronic liver failure (AcoChr) who did not undergo liver transplantation.

Devascularization surgical model of acute liver failure in minipigs

AIM

The study was designed to develop a readily reproducible model of acute liver failure (ALF) in the minipig, to gain an 8-hour therapeutic window to mimic, as closely as possible, acute liver failure in man.

METHOD

We used reversible devascularization model of ALF in the minipig involving hepatic artery ligation and establish an end-to-side portocaval anastomosis. Standard laboratory monitoring was complemented with intracranial pressure (ICP) measurement.

MATERIAL

Twenty minipigs (weight 25-30 kg) were used for the experiment. The animals were divided into 3 groups: I: 10 animals in an experimental group with ALF; II: 5 animals in an experimental group with ALF and ICP measurement, and III: 5 animals in a control group without ALF.

RESULTS

Laboratory testing has shown the significant changes in levels of AST (33.44 +/- 39.96 vs. 1.56 +/- 0.50 mmol/l), lactate (2.97 +/- 1.16 vs. 1.18 +/- 0.61 mmol/l), and ammonia (264.3 +/- 93.05 vs. 42.5 +/- 12.98 mmol/l) between ALF groups and controls (p < 001) 6 h after the operative procedure, and significant changes in hypoglycemia and intracranial pressure were found 4 h after the operative procedure. The difference in Quick values (67.4 +/- 17.03 vs. 75.2 +/- 2.68) was not significant. We assume that the therapeutic window starts 4 h after the beginning of the experiment.

CONCLUSION

Our devascularization model of ALF is simple and readily reproducible. The therapeutic window occurring shortly after surgery and persisting for a mean 9 h is suitable to evaluate bioartificial liver devices.

Hodgkin' s disease with fulminant non-alcoholic steatohepatitis

We report a woman with daily febrile episodes who developed fulminant hepatic failure. A percutaneous liver biopsy demonstrated non-alcoholic steatohepatitis, with no evidence of neoplastic infiltration. Post-mortem examination revealed stage IV Hodgkin's disease with trivial liver involvement. Rapidly progressive steatohepatitis causing acute liver failure may be a paraneoplastic presentation of Hodgkin's disease, possibly mediated by cytokines.

Factors associated with fulminant liver failure during an outbreak among injection drug users with acute hepatitis B

Death related to acute hepatitis B occurs in approximately 1% of patients. We investigated an outbreak of hepatitis B virus (HBV) infections among injection drug users (IDUs) resulting in several deaths. We conducted a case-control study of fulminant (case patients) and nonfulminant (control patients) HBV infections. We directly sequenced the entire HBV genome from fulminant and nonfulminant cases. From October 1998 to July 2000, 21 acute HBV infections, including 10 fulminant hepatitis B cases, were identified. The median age was 30 (range, 18-49) years, 12 (57%) were female, 20 (95%) were American Indians, and 20 (95%) reported injecting illicit drugs. All patients with fulminant hepatitis B died (case-fatality rate = 47.6%). Case patients (n = 5) and control patients (n = 9) were similar with respect to age, sex, race, and hepatitis C virus serostatus. All case patients used acetaminophen during their illness compared with 44% of control patients (P =.08). Compared with control patients, case patients lost more weight in the 6 months before illness (P =.04); during their illness, they used more alcohol (P =.03) and methamphetamine (P =.04). All 9 isolates sequenced were genotype D, shared 99.7% homology, and included mutations previously described in association with fulminant hepatitis B. In conclusion, a high prevalence of exposure to factors potentiating hepatic damage with acute hepatitis B contributed to the outbreak's high mortality rate; mutations present in the outbreak strain might also have been a factor. Improved vaccination coverage among IDUs has the potential to prevent similar outbreaks in the future.

In vitro evaluation of cross-circulation system using semipermeable membrane combined with whole liver perfusion

INTRODUCTION

Many types of isolated hepatocytes-based bioartificial liver have been developed. However, to maintain hepatocyte-specific functions for a long period is still a significant challenge. The possibilities of rejection or viral transmission still remain as untackled obstacles. We developed a cross-circulation system, using a semipermeable membrane combined with whole liver perfusion. Detoxifying functions of the extracorporeal porcine liver and molecular movements across the membrane were evaluated in vitro.

METHODS

The hollow-fiber module has a molecular cutoff of 100 kD. A spiked solution containing 500 mL low molecular dextran solution spiked with 12 mg ammonium chloride, 500 mg D-galactose, and 300 mg lidocaine, which mimicked a patient, was recirculated through the inner fiber space. The extracorporeal liver perfusion circuit consisted of an extra-fiber spaces. A reservoir containing 1000 mL healthy pig plasma, a membrane oxygenator, and a porcine whole liver. Both circuits circulated in the opposite direction for 6 hours.

RESULT

In 6 hours, 47.3% +/- 10.2% of ammonia, 89.5% +/- 1.7% of D-galactose, and 95.5% +/- 1.0% of lidocaine were eliminated from the circuits; 66.5 +/- 11.1 mg of urea were produced at the same time. Oxygen consumption was maintained between 0.248 and 0.259 mL/100 g liver/min for 6 hours. Movement of IgM was completely blocked by the 100-kD membrane, whereas albumin was freely transferred from the reservoir to the intrafiber space.

CONCLUSION

The perfusion experiments showed the possibility of using a whole liver with oxygenated plasma perfusion in a bioartificial liver system in vitro.

Serum from patients with fulminant hepatic failure causes hepatocyte detachment and apoptosis by a beta(1)-integrin pathway

Hepatocyte transplantation is restricted by the impaired ability of hepatocytes to engraft and survive in the damaged liver. Understanding the mechanisms that control this process will permit the development of strategies to improve engraftment. We studied changes in liver matrix during acute injury and delineated the mechanisms that perturb the successful adhesion and engraftment of hepatocytes. Collagen IV expression was increased in sinusoidal endothelium and portal tracts of fulminant hepatic failure explants, whereas there were minimal changes in the expression of fibronectin, tenascin, and laminin. Using an in vitro model of cellular adhesion, hepatocytes were cultured on collagen-coated plates and exposed to serum from patients with liver injury to ascertain their subsequent adhesion and survival. There was a rapid, temporally progressive decrease in the adhesive properties of hepatocytes exposed to such serum that occurred within 4 hours of exposure. Loss of activity of the beta1-integrin receptor, which controls adhesion to collagen, was seen to precede this loss of adhesive ability. Addition of the beta1-integrin activating antibody (TS2/16) to cells cultured with liver injury serum significantly increased their adhesion to collagen, and prevented significant apoptosis. In conclusion, we have identified an important mechanism that underpins the failure of infused hepatocytes to engraft and survive in liver injury. Pretreating cells with an activating antibody can improve their engraftment and survival, indicating that serum from patients with liver injury exerts a defined nontoxic biological effect. This finding has important implications in the future of cellular transplantation for liver and other organ diseases.

Molecular adsorbent recirculating system for acute and acute-on-chronic liver failure: a meta-analysis

Molecular adsorbent recirculating system (MARS) is an important option for patients with liver failure to give them additional time for recovery or to serve as a "bridge" to transplantation. However, its effect on survival for such patients is not well known. Our aim was to assess the treatment effects of MARS on patients with acute and acute-on-chronic liver failure. The outcomes measure evaluated was survival. We searched Medline (1966-2002) and EMBASE (1974-2002) using the terms liver failure, liver support systems, and MARS. Our search was extended to the Cochrane Controlled Trials Registry Database, published abstracts from 5 international conferences, Teraklin (the manufacturer of MARS), known contacts, and bibliographies from each full-published report. We included trials published in English and non-English languages. Eligible studies were randomized and nonrandomized controlled trials, which compared the treatment effects of MARS with standard medical treatment. Of the 206 articles screened, 4 randomized controlled trials including 67 patients were analyzed. Two nonrandomized trials with 61 patients were used for explorative analysis. The methodology, population, intervention, and outcomes of each selected trial were evaluated by duplicate independent review. Disagreements were resolved by consensus. In the primary meta-analysis, MARS treatment did not appear to reduce mortality significantly compared with standard medical treatment [relative risk (RR), 0.56; 95% confidence interval (CI), 0.28-1.14; P = .11]. Only 1 of the 4 randomized trials analyzed showed significant reduction in mortality. Sensitivity analysis of 3 peer-reviewed trials did not reduce mortality significantly with MARS treatment (RR, 0.72; 95% CI, 0.37-1.40; P = .33). Subgroup analysis of 2 trials for acute liver failure and another 2 trails for acute-on-chronic liver failure also did not reveal any benefit to survival with MARS treatment. In contrast, explorative analysis of 2 nonrandomized trials showed a significant survival benefit with MARS treatment (RR, 0.36; 95% CI, 0.17-0.76; P = .007). This was possibly related to bias in the selection of patients in the nonrandomized trials. In conclusion, MARS treatment had no significant survival benefit on patients with liver failure when compared with standard medical therapy. However, we found only a few trials with a small number of patients for the analysis, allowing for the possibility of false negative and erroneous conclusions. Well-conducted randomized trials are strongly recommended to define the role of MARS in the treatment of patients with liver failure.

Protective effect of MDL28170 against thioacetamide-induced acute liver failure in mice

Liver injury is known to often progress even after the hepatotoxicant is dissipated. The hydrolytic enzyme calpain, which is released from dying hepatocytes, destroys the surrounding cells and results in progression of injury. Therefore, control of calpain activation may be a suitable therapeutic intervention in cases of fulminant hepatic failure. This study evaluated the effects of a potent cell-permeable calpain inhibitor, MDL28170, and its mechanisms of action on thioacetamide (TAA)-induced hepatotoxicity in mice. We found that MDL28170 significantly decreased mortality and change in serum transaminase after TAA administration. The necroinflammatory response in the liver was also suppressed. Furthermore, a significant suppression of hepatocyte apoptosis could be found by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay. The upregulation of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-alpha), both of which are known to mediate the propagation of inflammation, was abolished. MDL2810 also effectively blocked hepatic stellate cell activation, which is assumed to be the early step in liver fibrosis. These results demonstrated that MDL28170 attenuated TAA-induced acute liver failure by inhibiting hepatocyte apoptosis, abrogating iNOS and TNF-alpha mRNA upregulation and blocking hepatic stellate cell activation.

Artificial and bioartificial support systems for liver failure

BACKGROUND

Artificial and bioartificial liver support systems may 'bridge' patients with acute or acute-on-chronic liver failure to liver transplantation or recovery.

OBJECTIVES

To evaluate beneficial and harmful effects of artificial and bioartificial support systems for acute and acute-on-chronic liver failure.

SEARCH STRATEGY

Trials were identified through The Cochrane Hepato-Biliary Group Controlled Trials Register (September 2002), The Cochrane Central Register of Controlled Trials on The Cochrane Library (Issue 3, 2002), MEDLINE (1966 - September 2002), EMBASE (1985 - September 2002), and The Chinese Biomedical Database (September 2002), manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies.

SELECTION CRITERIA

Randomised clinical trials on artificial or bioartificial support systems for acute or acute on-chronic liver failure were included irrespective of blinding, publication status, or language. Non-randomised studies were included in explorative analyses.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by three reviewers. Results were presented as relative risks (RR) with 95% confidence intervals (CI). Sources of heterogeneity were explored through sensitivity analyses and meta-regression. The primary outcome was mortality.

MAIN RESULTS

Twelve trials on artificial or bioartificial support systems versus standard medical therapy (483 patients) and two trials comparing different artificial support systems (105 patients) were included. Most trials had unclear methodological quality. Compared to standard medical therapy, support systems had no significant effect on mortality (RR 0.86; 95% CI 0.65-1.12) or bridging to liver transplantation (RR 0.87; 95% CI 0.73-1.05), but a significant beneficial effect on hepatic encephalopathy (RR 0.67; 95% CI 0.52-0.86). Meta-regression indicated that the effect of support systems depended on the type of liver failure (P = 0.03). In subgroup analyses, artificial support systems appeared to reduce mortality by 33% in acute-on-chronic liver failure (RR 0.67; 95% CI 0.51-0.90), but not in acute liver failure (RR 0.95; 95% CI 0.71-1.29). Two trials comparing artificial support systems showed significant mortality reductions with intermittent versus continuous haemofiltration (RR 0.58; 95% CI 0.36-0.94) and no significant difference between five versus ten hours of charcoal haemoperfusion (RR 1.03; 95% CI 0.65-1.62). The incidence of adverse events was inconsistently reported.

REVIEWER'S CONCLUSIONS

This Review indicates that artificial support systems may reduce mortality in acute-on-chronic liver failure. Artificial and bioartificial support systems did not appear to affect mortality in acute liver failure. However, considering the strength of the evidence additional randomised clinical trials are needed before any support system can be recommended for routine use.

Liver necrosis and fulminant hepatic failure in rats: protection by oxyanionic form of tungsten

The hepatic lesion produced as a result of oxidative stress is of wide occurrence. In the present study, the effect of tungsten on liver necrosis and fulminant hepatic failure (FHF) has been studied in rats treated with various compounds known to produce oxidative stress. Supplementation of animals with sodium tungstate for 7 weeks before the induction of liver injury by chemicals including thioacetamide (TAA), carbon tetrachloride (CCl(4)), or chloroform (CHCl(3)) could protect progression of hepatic injury. Various biochemical changes associated with liver damage and oxidative stress were measured. Hepatic malondialdehyde content, endogenous tripeptide, and reduced glutathione were measured as oxidative stress markers. The activity of xanthine oxidase, which generates reactive oxygen species (ROS) as a by-product, was also determined and found to be perturbed. Tungsten supplementation to rats caused a significant decrease in lipid peroxidation and lowered the levels of the biochemical markers of hepatic lesions produced by TAA, CCl(4) (CCl(4)), or CHCl(3). Tungsten could also cause an increase in the survival rate in rats receiving lethal doses of TAA, CCl(4), or CHCl(3). The protective effect of tungsten, however, is suggested to be limited to the conditions where the hepatic lesion is reported to be due to the generation of ROS. The progression of liver injury produced by the compounds causing oxidative stress without initiating the generation of free radicals such as bromobenzene (BB), or acetaminophen (AAP), could not be inhibited by tungsten. The possible mechanism explaining the role of oxyanionic form of tungsten in free radical-induced hepatic lesions is discussed.

Effect of Acanthopanax koreanum Nakai (Araliaceae) on D-galactosamine and lipopolysaccharide-induced fulminant hepatitis

The hepatoprotective effects of Acanthopanax koreanum Nakai (Araliaceae) were evaluated in D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure in mouse. Preparations of Acanthopanax koreanum used were an ethanol extract, a water extract, and the ethanol-soluble and ethanol-insoluble components of the water extract of roots or stems of the plant. Mice were pretreated with various extracts by intraperitoneal injection or orally, 12 and 1 h before intraperitoneal injection of D-galactosamine and lipopolysaccharide (LPS). Intraperitoneal pretreatment with the water extract or the ethanol-insoluble component of the water extract markedly reduced the elevated levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-alpha (TNF-alpha), reduced the histological changes in the liver, and attenuated hepatocyte apoptosis confirmed by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling method and DNA fragmentation assay. Oral pretreatment with the ethanol-insoluble component of the water extract also reduced serum AST, ALT, and TNF-alpha levels. The present study shows that the ethanol-insoluble component of a water extract from Acanthopanax koreanum has a protective effect against the induction of fulminant hepatitis in mice by D-galactosamine and lipopolysaccharide.

Liver transplantation in exertional heat stroke: a medical dilemma

BACKGROUND

Exertional heat stroke (EHS) is a life-threatening condition caused by an extreme elevation in core body temperature. Hepatic involvement is one of the hallmarks of heat stroke, affecting nearly all heat stroke patients. It is usually manifested by increased serum levels of liver enzymes, but acute liver failure has also been reported. Liver transplantation has been proposed as a potential treatment in cases of severe liver failure, but there are no unanimous criteria pointing to the right stage in which to conduct the transplantation.

CASE PRESENTATION

We report a case of an 18-year old patient who suffered heat-induced liver failure. The patient was referred for orthotopic liver transplantation (OLT) but spontaneously recovered completely with conservative treatment.

CONCLUSIONS

This case demonstrates the complexity of the decision for liver transplantation in EHS. The various prognostic criteria of acute hepatic failure and their relevance to EHS are critically reviewed, with an aim to assess their application for such a condition.

Hepatitis C Infection: A Clinical Review

Nearly three million persons in the United States are viremic with hepatitis C (HCV). Despite a decreasing incidence of HCV in this country, the prevalence of HCV-related chronic liver disease is increasing. Most infections in the United States are acquired by intravenous drug use. The chronicity rate of HCV is high, reaching 85% in some populations, and the risk of progression to advanced liver disease is as high as 20% within twenty years of infection. Host factors like alcohol use accelerate the rate of progression. The enzyme immunoassay is the preferred initial test for diagnosis; the third generation assay has greater than a 99% specificity in immunocompetent patients. Barring contraindications, the standard of care for treatment of chronic HCV has become pegylated interferon and ribavirin. With this therapy, the cure rate for treatment-naïve patients is about 55%, but rates are higher in certain groups. Common side effects of therapy include neuropsychiatric symptoms, influenza-like symptoms and hematological abnormalities.

Acetylcysteine treatment for non-acetaminophen-induced acute liver failure

OBJECTIVE

To evaluate the effectiveness of intravenous acetylcysteine in the treatment of non-acetaminophen-induced acute liver failure (ALF).

DATA SOURCES

A search of MEDLINE (1966-March 2003), International Pharmaceutical Abstracts (1970-2003), and Cochrane Library (2003, issue 3) databases was conducted, using the search terms acetylcysteine, non-acetaminophen-induced hepatic failure, liver failure, intravenous, and treatment.

DATA SYNTHESIS

All of the studies found were small and do not provide conclusive evidence that acetylcysteine benefits this subgroup of patients. Microvascular regional benefits were seen, but clinical outcomes have not been studied.

CONCLUSIONS

Intravenous acetylcysteine should not be used routinely for treatment of non-acetaminophen-induced ALF. Further large-scale studies are needed to evaluate clinical outcomes.

A liver transplant center experience with liver dialysis in the management of patients with fulminant hepatic failure: a preliminary report

Among extracorporeal liver support devices, liver dialysis is cleared by the U.S. Food and Drug Administration to be used for the management of fulminant hepatic failure (FHF). The outcomes of patients following liver dialysis need to be clearly evaluated. Among the 25 patients with FHF admitted to the Liver ICU between May 2000 and November 2002, 12 underwent liver dialysis, including 6 men and 6 women, of mean age 32 years. The causes of FHF were identified as acetaminophen (n = 10), herbal medications (n = 1) and autoimmune disease (n = 1). At presentation, the mean total bilirubin was 9.35 mg/dL (range, 0 to 1.3), mean ALT 3015 U/L (range, 0 to 48), mean AST 3457 (range, 0 to 42), mean ammonia 98 micromol/L (range, 10 to 60) and mean INR 1.88. A control group including 13 patients (2 men and 11 women), of mean age 27.8 years mean total bilirubin 5.66, mean ALT 3494, mean AST 3528, mean ammonia 113 and mean INR 3, were not treated with liver dialysis, due to the lack of machine availability or physician's choice. The causes of FHF were acute hepatitis B (n = 1), acetaminophen (n = 10) or unknown (n = 2). There was no statistically significant difference in the baseline characteristics of the two groups (P >.05). Among the liver dialysis group, 1 patient died, 2 underwent OLTx, and 9 were discharged home. Among the control group; 4 patients died, 2 underwent OLTx, and 7 were discharged home. Preliminary results seem to support survival benefit among patients who underwent liver dialysis compared to non-liver dialysis; however, further randomized control trials are warranted to verify this observation.

cDNA microarray analysis in hepatocyte differentiation in Huh 7 cells

The risk of xenozoonosis infections poses the greatest obstacle against the clinical application of a hybrid artificial liver support system (HALSS). Primary human hepatocytes are an ideal source for HALSS, but the shortage of human livers available for hepatocyte isolation limits this modality. To resolve this issue, we previously demonstrated the upregulation of hepatocyte-specific function by spheroid formation in polyurethane foam and by culturing with the histone deacetylase inhibitor, trichostatin A (TSA), in a human hepatoma cell line (Huh 7). In this article we analyze the gene expression profile using cDNA microarray (1281 genes) in spheroid formation or culturing with TSA in Huh 7 to determine the target genes in hepatocyte differentiation. In both the spheroid formation and in the culture with TSA, the Oct-3/4 transcription factor was upregulated more thantwofold, while the early growth response-1 (EGR-1) transactivator was downregulated less than 0.5-fold. These results indicate that expressions of Oct-3/4 and EGR-1 may be key factors in the induction of hepatocyte differentiation in Huh 7.

Pediatric fulminant hepatic failure in endemic areas of hepatitis B infection: 15 years after universal hepatitis B vaccination

To investigate the role of hepatitis B virus (HBV) infection in pediatric fulminant hepatic failure (FHF) after the launch of universal HBV vaccination, the authors analyzed the data from patients with FHF collected from a nationwide collaborative study group. Children aged 1 month to 15 years who were diagnosed with FHF (62 males and 33 females) between 1985-1999 were included. HBV infection (hepatitis B surface antigen [HBsAg] and/or immunoglobulin M hepatitis B core antibody [IgM anti-HBc] seropositive) accounted for 46% (43 of 95 cases) of all the cases of FHF. The average annual incidence of FHF in the time period 1985-1999 was 0.053/100,000 in the group of patients ages 1-15 years and 1.29/100,000 in those patients age < 1 year. Approximately 61% (58 of 95 cases) of all FHF cases were infants. The percentage of HBV infection was found to be higher in infants (57%) compared with children ages 1-15 years (27%) (P = 0.004). The incidence rate ratio of those patients age < 1 year to those ages 1-15 years was 54.2 for HBV-positive FHF and 15.2 for HBV-negative FHF. Maternal HBsAg was found to be positive in 97% of the infants with HBV-positive FHF, and hepatitis B e antigen (HBeAg) was found to be negative in 84% of these infants. Approximately 74% of all HBV-positive FHF patients and 81% of the infantile HBV-positive patients had been vaccinated. In conclusion, within the first 15 years of universal vaccination, HBV was found to rarely cause FHF in children age > 1 year but remained a significant cause of FHF in infants. HBV-positive FHF was prone to develop in infants born to HBeAg-negative, HBsAg-carrier mothers; these infants had not received hepatitis B immunoglobulin according to the vaccination program in place.

Melatonin inhibits nuclear factor kappa B activation and oxidative stress and protects against thioacetamide induced liver damage in rats

BACKGROUND/AIMS

Free radical-mediated oxidative stress has been implicated in the pathogenesis of acute liver injury. The aim of our study was to investigate whether melatonin, a potent free radical scavenger could prevent fulminant hepatic failure in rats.

METHODS

Liver damage was induced by two consecutive injections of thioacetamide (TAA, 300 mg/kg/i.p.) at 24 h intervals. Treatment with melatonin (3 mg/kg/daily, i.p) was initiated 24 h prior to TAA.

RESULTS

Twenty-four h after the second TAA injection, serum liver enzymes and blood ammonia were lower in rats treated with TAA+melatonin compared to TAA (P<0.001). Liver histology was significantly improved and the mortality in the melatonin-treated rats was decreased (P<0.001). The increased nuclear binding of nuclear factor kappa B in the livers of the TAA-treated rats, was inhibited by melatonin. The hepatic levels of thiobarbituric acid reactive substances, protein carbonyls and inducible nitric oxide synthase were lower in the TAA+melatonin-treated group (P<0.01), indicating decreased oxidative stress and inflammation.

CONCLUSIONS

In a rat model of TAA-induced fulminant hepatic failure, melatonin improves survival and reduces liver damage and oxidative stress. The results suggest a causative role of oxidative stress in TAA-induced hepatic damage and suggest that melatonin may be utilized to reduce liver injury associated with oxidative stress.

Artificial and bioartificial support systems for liver failure

BACKGROUND

Artificial and bioartificial liver support systems may 'bridge' patients with acute or acute-on-chronic liver failure to liver transplantation or recovery.

OBJECTIVES

To evaluate beneficial and harmful effects of artificial and bioartificial support systems for acute and acute-on-chronic liver failure.

SEARCH STRATEGY

Trials were identified through The Cochrane Hepato-Biliary Group Controlled Trials Register (September 2002), The Cochrane Central Register of Controlled Trials on The Cochrane Library (Issue 3, 2002), MEDLINE (1966 - September 2002), EMBASE (1985 - September 2002), and The Chinese Biomedical Database (September 2002), manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies.

SELECTION CRITERIA

Randomised clinical trials on artificial or bioartificial support systems for acute or acute on-chronic liver failure were included irrespective of blinding, publication status, or language. Non-randomised studies were included in explorative analyses.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by three reviewers. Results were presented as relative risks (RR) with 95% confidence intervals (CI). Sources of heterogeneity were explored through sensitivity analyses and meta-regression. The primary outcome was mortality.

MAIN RESULTS

Twelve trials on artificial or bioartificial support systems versus standard medical therapy (483 patients) and two trials comparing different artificial support systems (105 patients) were included. Most trials had unclear methodological quality. Compared to standard medical therapy, support systems had no significant effect on mortality (RR 0.86; 95% CI 0.65-1.12) or bridging to liver transplantation (RR 0.87; 95% CI 0.73-1.05), but a significant beneficial effect on hepatic encephalopathy (RR 0.67; 95% CI 0.52-0.86). Meta-regression indicated that the effect of support systems depended on the type of liver failure (P = 0.03). In subgroup analyses, artificial support systems appeared to reduce mortality by 33% in acute-on-chronic liver failure (RR 0.67; 95% CI 0.51-0.90), but not in acute liver failure (RR 0.95; 95% CI 0.71-1.29). Two trials comparing artificial support systems showed significant mortality reductions with intermittent versus continuous haemofiltration (RR 0.58; 95% CI 0.36-0.94) and no significant difference between five versus ten hours of charcoal haemoperfusion (RR 1.03; 95% CI 0.65-1.62). The incidence of adverse events was inconsistently reported.

REVIEWER'S CONCLUSIONS

This Review indicates that artificial support systems may reduce mortality in acute-on-chronic liver failure. Artificial and bioartificial support systems did not appear to affect mortality in acute liver failure. However, considering the strength of the evidence additional randomised clinical trials are needed before any support system can be recommended for routine use.

Fulminant hepatic failure

Fulminant hepatic failure is a rapidly progressive and often fatal syndrome, and the only definitive treatment is liver transplantation. However, given the scarcity of available grafts, the mainstay of therapy remains supportive care until there is spontaneous recovery or until a suitable donor liver becomes available. After initial assessment and stabilization, patients should be transferred to the nearest liver transplant center as soon as possible, as they can deteriorate rapidly. All patients with fulminant hepatic failure must be monitored closely and treated for hepatic encephalopathy, coagulopathy, gastrointestinal bleeding, renal failure, cerebral edema, and metabolic derangement.

Clinical features of non-Hodgkins lymphoma presenting with acute liver failure: a report of five cases and review of published experience

Hematological malignancies frequently affect the liver, but typically do not result in hepatic dysfunction and rarely present with advanced hepatic involvement. We report five patients who presented with advanced hepatic involvement and were found to have a high-grade lymphoma infiltrating the liver. Despite early diagnosis and initiation of therapy, all five patients deteriorated rapidly and died shortly after the onset of liver failure. Several similar cases have been reported. They share common clinical features, including hepatomegaly, lactic acidosis, and death shortly after the onset of symptoms. Non-Hodgkins lymphoma is a common malignancy, which is increasing in incidence. Non-Hodgkins lymphoma is not commonly entertained as an etiology of advanced liver failure and is likely underrecognized. In cases of acute advanced liver failure without an apparent etiology, especially if associated with hepatomegaly and lactic acidosis, lymphoma should be considered because of its poor prognosis and potential for treatment if recognized early. Liver biopsy is an invaluable tool that provides an early diagnosis while excluding other potential etiologies for acute advanced liver failure.

Hepatic stimulator substance administration ameliorates liver regeneration in an animal model of fulminant hepatic failure and encephalopathy

AIMS/BACKGROUND

Hepatic stimulator substance (HSS) is a liver-specific growth factor implicated in hepatocellular proliferation and hepatoprotection in models of acute liver injury. In the present study, we examined the effect of exogenous HSS administration on liver proliferating capacity and survival outcome in an experimental animal model of fulminant hepatic failure (FHF) and encephalopathy, induced by repeated injections of thioacetamide (TAA) in rats.

METHODS

Fulminant hepatic failure was induced in adult male Wistar rats by three consecutive intraperitoneal injections of TAA (400 mg/kg of body weight), at 24 h time intervals. The animals received intraperitoneally either a saline solution or HSS (50 mg protein/kg of body weight), 2 h after the second and third TAA injections. The animals were killed at 6, 12 and 18 h post the last injection of TAA.

RESULTS

Levels of liver enzymes and urea in serum, blood ammonia values, liver histology, stage of hepatic encephalopathy and survival were statistically significantly improved in TAA-intoxicated and HSS-treated rats compared to TAA-intoxicated and saline-treated ones. Furthermore, HSS ameliorated liver regenerative indices--DNA biosynthesis, thymidine kinase activity and hepatocyte mitotic activity--in a statistically significant manner.

CONCLUSIONS

Our data suggest the beneficial effect of HSS administration in this animal model of FHF and encephalopathy, supporting evidence for a possible use of HSS as supportive therapy, by increasing hepatocellular proliferation, in management of FHF.

[Fulminant hepatic failure and liver transplantation. Experience of the Hospital Virgen de la Arrixaca]

INTRODUCTION

Medical treatment for fulminat hepatic failure seeks spontaneous recovery of the liver function, but the results are very discouraging (50-80% mortality). Liver transplantation is an option in patients with a poor evolution despite medical treatment, with survival rates of > 50%. The ideal moment for performing the transplant is controversial, as it should not be done too soon, when the liver disease is still reversible, or tool late, when the patient is in an irreversible clinical situation.

PATIENTS AND METHOD

A retrospective review was made of the clinical histories of 34 patients admitted to our hospital with a diagnosis of fulminant hepatic failure, of whom 26 underwent transplantation. The most frequent cause was viral, with 10 cases (38%); no aetiology at all could be established in 11 cases (42%). Thirteen patients had preoperative complications, the most frequent being renal insufficiency. As for degree of ABO/DR compatibility, 13 cases were identical (40%), 17 compatible (51%) and the other 3 incompatible (9%).

RESULTS

Thirty-three transplants were performed in 26 patients: 4 were retransplants due to chronic rejection, 2 for primary graft failure and 1 for hyperacute rejection. The overall mortality rate was 46% (12 patients), the most frequent cause of death being infection (50%). The overall actuarial survival rate was 68% at 1 year, 63% at 3 years and 59% at 5 years. The factors of poor prognosis were renal and respiratory insufficiency, a grade D electroencephalogram, and encephalopathy grades III and IV, the latter being the only prognostic factor identified in the multivariate analysis. The prognostic factors for mortality were a grade D electroencephalogram, encephalopathy grades III and IV and respiratory insufficiency, the latter being the only prognostic factor identified in the multivariate analysis.

CONCLUSIONS

The achievement of good results with the use of transplantation in the management of fulminant hepatic failure depends on an optimum selection of transplant candidates, which means identifying them early, i.e. early indication for transplant, reduction in mean waiting time and exclusion of factors of poor prognosis.

[Fulminant hepatitis B]

Fulminant hepatitis, or fulminant hepatic failure, is defined as a clinical syndrome of severe liver function impairment, which causes hepatic coma and the decrease in synthesizing capacity of liver, and develops within eight weeks of the onset of hepatitis. Several independent factors influence the survival of patients: age, the cause of liver disease, the degree and the duration of encephalopathy in relation to the onset of the disease, and the prevention of complications. Over the years many intensive treatments have been practiced. Liver transplantation is expensive, and patients who survive transplantation require life-long immunosuppression, clinical care and complications management. Without transplantation fulminant hepatitis and hepatic failure might be completely recovered spontaneously, and the patient could expect a normal life. Two cases of fulminant B hepatitis with intensive care treatment, and their survival despite unfavorable prognosis are presented in this paper. The management of patients with fulminant hepatitis required intensive monitoring and therapeutic measures, including corticosteroids. The prognosis for survival without transplantation in fulminant hepatitis is limited by the measures of medical treatment and new specific therapeutic modalities which must be developed through basic research.

Fulminant liver disease

Fulminant liver disease, acute liver failure (ALF), is one of the most intriguing and challenging conditions in the entire field of internal medicine. ALF is defined as the onset of hepatic encephalopathy and coagulopathy in patients with no known underlying liver disease within 8 to 26 weeks of onset of illness. Many cases develop within a few days, dramatically transforming an otherwise healthy individual to a patient with a high risk for developing multi-organ failure and death.

Liver transplantation for fulminant hepatic failure: experience with more than 200 patients over a 17-year period

OBJECTIVE

To analyze outcomes after liver transplantation (LT) in patients with fulminant hepatic failure (FHF) with emphasis on pretransplant variables that can potentially help predict posttransplant outcome.

SUMMARY BACKGROUND DATA

FHF is a formidable clinical problem associated with a high mortality rate. While LT is the treatment of choice for irreversible FHF, few investigations have examined pretransplant variables that can potentially predict outcome after LT.

METHODS

A retrospective review was undertaken of all patients undergoing LT for FHF at a single transplant center. The median follow-up was 41 months. Thirty-five variables were analyzed by univariate and multivariate analysis to determine their impact on patient and graft survival.

RESULTS

Two hundred four patients (60% female, median age 20.2 years) required urgent LT for FHF. Before LT, the majority of patients were comatose (76%), on hemodialysis (16%), and ICU-bound. The 1- and 5-year survival rates were 73% and 67% (patient) and 63% and 57% (graft). The primary cause of patient death was sepsis, and the primary cause of graft failure was primary graft nonfunction. Univariate analysis of pre-LT variables revealed that 19 variables predicted survival. From these results, multivariate analysis determined that the serum creatinine was the single most important prognosticator of patient survival.

CONCLUSIONS

This study, representing one of the largest published series on LT for FHF, demonstrates a long-term survival of nearly 70% and develops a clinically applicable and readily measurable set of pretransplant factors that determine posttransplant outcome.

Troglitazone-induced liver failure: a case study

BACKGROUND

Troglitazone was removed from the U.S. market because its use was associated with an increased risk of liver failure. We evaluated the clinical features of all cases reported to the Food and Drug Administration and estimated the duration and magnitude of the risk of liver failure associated with continued use of the drug.

METHODS

Data from cases of liver failure associated with troglitazone use were abstracted and analyzed. The extent of troglitazone use was determined from national marketing data, and the duration of use was estimated with data from a large, multistate, health care company. Survival analysis was performed to estimate monthly incidence rates and the cumulative risk of liver failure.

RESULTS

Ninety-four cases of liver failure (89 acute, 5 chronic) were reported. Of the acute cases, 58 (67%) were women and only 11 (13%) recovered without liver transplantation. Progression from normal hepatic functioning to irreversible liver injury occurred within 1 month in 19 patients who were indistinguishable clinically from the 70 patients who had an unknown time course to irreversibility, except for the post hoc observation that prior cholecystectomy was less common in those with rapid onset. The incidence of liver failure was elevated from the first through at least the 26th month of troglitazone use. Accounting for case underreporting, the number needed to harm from troglitazone use was between 600 to 1500 patients at 26 months.

CONCLUSION

The progression to irreversible liver injury probably occurred within a 1-month interval in most patients, casting doubt on the value of monthly monitoring of serum aminotransferase levels as a means of preventing troglitazone-induced acute liver failure. The cumulative risk of hepatic failure increased with continued use.

Serum phosphorus levels predict clinical outcome in fulminant hepatic failure

The aim of this pilot study was to evaluate the incidence of hypophosphatemia and its association with clinical outcome in fulminant hepatic failure (FHF). Patients with FHF referred for orthotopic liver transplantation (OLT) between January, 1991 and May, 2002 were identified. FHF was defined as the development of coagulopathy and encephalopathy within 8 weeks of onset of jaundice. Demographic and laboratory data, including serum phosphate, calcium, magnesium, creatinine, and PT/INR were obtained from medical records. Clinical outcomes (death, OLT, or hepatic recovery) and associated morbidities (renal failure, bleeding, and sepsis) also were noted. Thirty-eight patients, 8 men and 30 women, aged 34 +/- 4 years, were included in the study. Hypophosphatemia (< 2.5 mg/dL) developed in 33 of 38 (87%) patients within 10 days of referral. Twelve patients (32%) died, 14 patients (37%) underwent OLT, and 12 patients (32%) recovered. The mean nadir serum phosphorus level was significantly lower in those who recovered compared with those who either died or required OLT (1.18 +/- 0.54 versus 1.79 +/- 1.00 mg/dL; P =.02). A trend toward lower mean serum phosphorus level also was noted in those who recovered compared with those who died (1.18 +/- 0.54 versus 1.96 +/- 1.35 mg/dL; P =.09). Serum phosphorus levels > 2.5 mg/dL was a predictor of mortality, and when used alone, was equivalent to the King's College Criteria. In conclusion, hypophosphatemia occurred frequently in patients with FHF. Lower serum phosphorus levels were observed in patients who recovered as compared with those who died or required OLT, and may be associated with recovery of hepatic function. The greater decline in serum phosphorus level in those who recover hepatic function may represent cellular use of phosphorus during hepatocyte regeneration.

Health and economic impact of posttransfusion hepatitis B and cost-effectiveness analysis of expanded HBV testing protocols of blood donors: a study focused on the European Union

BACKGROUND

Residual risk of posttransfusion hepatitis B (PT-HB) may be reduced through implementation of HBV NAT or the new, enhanced-sensitivity HBsAg assays in routine donor testing. However, there are some doubts about the cost-effectiveness of these new safety measures, because hepatitis B acquired in adulthood is not regarded as a severe disease in western countries.

STUDY DESIGN AND METHODS

A computer model was designed to estimate the health outcomes and associated costs of patients with PT-HB. Results from this model and estimations of the residual risk of HBV transmission, the risk reduction yielded by the new assays, and their cost were used to calculate the cost-effectiveness of including the new HBsAg assays or single-sample HBV NAT in the routine screening of blood donors.

RESULTS

The model predicts that 0.97 percent of patients with PT-HB die of liver disease (54% of them due to fulminant hepatitis). The mean loss of life expectancy was 0.178 years per patient, and the present value of the lifetime costs of treating PT-HB was 4160 euros per patient. Single-donor HBV NAT or the new HBsAg assays would increase the life expectancy of blood recipients by 16 (95% CI, 8-40) or 14 (95% CI, 7-28) years, respectively, per every 10 million donations tested. The projected cost per life-year gained was 0.79 (95% CI, 0.15-1.85) million euros for the enhanced-sensitivity HBsAg assays and 5.8 (95% CI, 1.9-13.1) million euros for single-donation HBV NAT, both compared with current HBsAg assays. If single-donation HBV NAT is compared with the new HBsAg assays, its cost- effectiveness ratio increases to 53 (95% CI, 16-127) million euros.

CONCLUSION

PT-HB has few health or economic repercussions. Single-donation HBV NAT would provide a small health benefit at a very high cost. Instead, in some circumstances, the cost-effectiveness of enhanced-sensitivity HBsAg assays would be within acceptable ranges for new public health interventions.

Utility of hepatic phosphorus-31 magnetic resonance spectroscopy in a rat model of acute liver failure

The ability to document the extent of hepatic injury and predict the outcome of fulminant hepatic failure would be helpful in identifying those patients who might benefit from liver transplantation. The aim of the present study was to determine whether in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS) accurately assesses the severity of liver damage and is of prognostic value in a D-galactosamine (D-galN)-induced model of acute liver failure. Adult male Sprague-Dawley rats (n = 36) received an intraperitoneal dose of D-galN (1.0 g/kg), and MRS examinations were performed at peak (48 hours) and in subsequent experiments, just prior to peak (30 hours) hepatic injury. Rats not exposed to D-galN served as controls. The concentration of hepatic phosphorylated metabolites decreased in proportion to the severity of liver injury at 48 hours. Significant correlations were detected between hepatic adenosine triphosphate (ATP) and serum aspartate aminotransferase, bilirubin, and percentage of hepatocyte necrosis identified histologically (r = -.91, -.74, and -.92, respectively; p < .001). Prior to peak hepatic injury (30 hours), 31P MRS was able to predict with 100% accuracy those rats that would survive (ATP > 2.3 mM) and those that would not (ATP < 1.5 mM). When an intermediate cutoff value of 2.0 mM was selected, ATP levels were able to correctly predict survival and death with 80% and 60% accuracy, respectively. These findings indicate that hepatic ATP levels as measured by 31P MRS provide a noninvasive indication of the severity of liver damage and serve as a useful prognostic indicator of outcome in this model of acute liver failure.

Paracetamol-induced hepatotoxicity at recommended dosage

In patients who develop liver damage following moderate paracetamol overdose in the order of 5-10 g daily, recent fasting and nutritional impairment have been identified as key precipitants. Hepatotoxicity caused by paracetamol at recommended dosage, in the absence of exposure to enzyme-inducing drugs, has recently been described as an idiosyncratic phenomenon. The possible importance of fasting and malnutrition in this setting is uncertain. We report a severely malnourished 53-year-old woman who developed severe hepatotoxicity whilst receiving paracetamol at recommended dosage (4 g daily) following a period of fasting, in the absence of enzyme-inducing agents. Subsequent paracetamol exposure up to 2.6 g daily thrice weekly, in the setting of ongoing malnutrition and fasting as before, did not lead to recurrent liver damage. These findings indicate that paracetamol-related liver damage occurring within recommended dosage guidelines can be a dose-dependent rather than necessarily idiosyncratic phenomenon, at least in the setting of recent fasting and severe malnutrition.

Artificial and bioartificial support systems for acute and acute-on-chronic liver failure: a systematic review

CONTEXT

Artificial and bioartificial support systems may provide a "bridge" for patients with severe liver disease to recovery or transplantation.

OBJECTIVE

To evaluate the effect of artificial and bioartificial support systems for acute and acute-on-chronic liver failure.

DATA SOURCES

Randomized trials on any support system vs standard medical therapy were included irrespective of publication status or language. Nonrandomized studies were included in explorative analyses. Trials were identified through electronic searches (Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Library, MEDLINE, EMBASE, and the Chinese Medical Database), bibliographies, and contact with experts. Searches were conducted of the entire databases through September 2002.

STUDY SELECTION

Of 528 references identified, 12 randomized trials with 483 patients were included. Eight nonrandomized studies were included in explorative analyses.

DATA EXTRACTION

Data were extracted and trial quality was assessed independently by 3 reviewers (L.L.K., J.L., B.A-N.). The primary outcome measure was all-cause mortality. Results were combined on the risk ratio (RR) scale. Random-effects models were used. Sources of heterogeneity were explored through meta-regression and stratified meta-analyses.

DATA SYNTHESIS

Of the 12 trials included, 10 assessed artificial systems for acute or acute-on-chronic liver failure and 2 assessed bioartificial systems for acute liver failure. Overall, support systems had no significant effect on mortality compared with standard medical therapy (RR, 0.86; 95% confidence interval [CI], 0.65-1.12). Meta-regression indicated that the effect of support systems depended on the type of liver failure (P =.03). In stratified meta-analyses, support systems appeared to reduce mortality by 33% in acute-on-chronic liver failure (RR, 0.67; 95% CI, 0.51-0.90), but not in acute liver failure (RR, 0.95; 95% CI, 0.71-1.29). Compared with randomized trials, nonrandomized studies produced significantly larger estimates of intervention effects (P =.01).

CONCLUSION

This review suggests that artificial support systems reduce mortality in acute-on-chronic liver failure compared with standard medical therapy. Artificial and bioartificial support systems did not appear to affect mortality in acute liver failure.

Liver transplantation for fulminant hepatic failure

The etiology and prognosis of individuals with various forms of fulminant hepatic failure are reviewed. Special techniques of clinical management and decision making as to when and to whom to transplant in cases of fulminant hepatic failure are reviewed.

Incidence of idiopathic acute liver failure and hospitalized liver injury in patients treated with troglitazone

OBJECTIVE

Troglitazone, a thiazolidinedione antidiabetic agent, was withdrawn from the U.S. market in March, 2000, after 94 cases of acute liver failure (ALF) were reported with its use. Based on a literature review, the estimated background rate of hospitalization for idiopathic acute liver injury is 22 per million person-years and for idiopathic ALF, less than 1 per million person-years. This study was conducted to estimate the incidence rates of hospitalized idiopathic acute liver injury and ALF among troglitazone-treated patients.

METHODS

An observational retrospective inception cohort of patients treated with troglitazone was assembled using claims data from a large multistate health care organization. Patients with at least 90 days of health plan enrollment before their first troglitazone prescription between April, 1997 and December, 1998 were enrolled. Hospitalized cases of potential troglitazone-induced acute liver injury or ALF were identified from claims data based on International Classification of Diseases, 9th Revision, coding. Primary medical records were reviewed for case validation, and incidence rates of acute liver injury were calculated using person-years of troglitazone exposure as the denominator.

RESULTS

A total of 7568 patients contributed 4020 person-years of troglitazone exposure. Of these, five were hospitalized with acute liver injury attributed to the drug and not explained by other causes. Incidence rates (95% CI) per million person-years of acute idiopathic liver injury were as follows: hospitalization (n = 5), 1244 (404, 2900); hospitalized jaundice (n = 4), 995 (271, 2546); and ALF (n = 1), 240 (6.3, 1385).

CONCLUSIONS

Troglitazone use was associated with a marked increase in risk of hospitalized acute idiopathic liver injury and ALF.

Etiopathogenesis of acute hepatic failure: Eastern versus Western countries

Etiopathogenesis of acute hepatic failure (AHF) in Eastern and Western countries is distinct. In the East hepatitis viruses cause AHF in more than 95% of such cases, while causes of AHF in the West are quite heterogenous. Hepatitis E virus is the major etiological agent of AHF in countries like India where the virus is hyperendemic. Occult HBV infection may also be causing AHF in a sizable proportion of cases in areas where chronic HBV infection frequency is high. Paracetamol causes AHF in about 70% cases in the UK and about 20% cases in USA, whereas in France and Denmark, non-steroidal anti-inflammatory drugs are more frequently associated with AHF. Hepatitis B virus causes AHF in about one-third of cases in the latter two countries.

Conditional cell ablation by tight control of caspase-3 dimerization in transgenic mice

Studying the effects of the loss of a specific cell type is a powerful approach in biology. Here we present a method based on the controlled activation of the apoptotic machinery. We expressed a modified caspase-3-containing chemical inducer of dimerization (CID)-binding sites in the livers of transgenic mice. In the absence of CID, no liver injury was detectable, underlining the absence of leakage in our system. In contrast, injection of the CID produced activation of the chimeric caspase-3, which led to a dose-dependent pure hepatocyte ablation with subsequent regeneration. This method is effective in both growing and nongrowing cells, and is therefore applicable to a wide range of cells and tissues. Moreover, because apoptosis has been described in numerous pathological circumstances, this system is useful for generating mouse models of human disorders as well as for studying the recovery or regeneration of tissues after cell loss.

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.

The role of lamivudine and predictors of mortality in severe flare-up of chronic hepatitis B with jaundice

Patients with chronic hepatitis B (CHB) may develop severe disease exacerbations (flare) with jaundice, and some may progress to fulminant hepatic failure. Whether early administration of lamivudine can prevent liver failure and mortality is uncertain. We investigated the role of lamivudine treatment in severe hepatitis B virus (HBV) exacerbations. Consecutive patients presented with severe flare-up of HBV (new onset of jaundice plus alanine aminotransferase greater than five times upper limit of normal) treated with lamivudine and historical controls who did not receive lamivudine were studied. All patients had no hepatic encephalopathy on admission. Univariate analysis and multivariate logistic regression were performed on various clinical and laboratory factors for the prediction of mortality. Twenty-eight patients treated with lamivudine and 18 controls were identified. Overall, nine patients died and two other received liver transplants for fulminant hepatic failure. Six of 28 (21.4%) lamivudine-treated patients vs five of 18 (27.8%) controls died or received a liver transplant (P = 0.62). On multivariate analysis, platelet < or = 143 x 10E9/L (odds ratio 22.4, 95% CI 1.8-281.6) and bilirubin > 172 micromol/L (odds ratio 18.4, 95% CI 1.5-228.5) were independent predictors of liver-related mortality. The mortality of patients who had thrombocytopenia and high bilirubin, thrombocytopenia, high bilirubin, and no risk factor were 69.2%, 11.1%, 12.5% and 0% respectively. Hence lamivudine confers no survival benefit to conventional treatment in severe exacerbations of CHB. Patients with thrombocytopenia and high bilirubin should be considered for liver transplantation.

Artificial and bioartificial support systems for liver failure: a Cochrane Hepato-Biliary Group Protocol

AIMS/BACKGROUND

Liver support systems may bridge patients to liver transplantation or recovery from liver failure. This review is to evaluate the beneficial and harmful effects of artificial and bioartificial support systems for acute and acute-on-chronic liver failure.

DATA SOURCES

Randomized trials on any support system versus standard medical therapy will be included irrespective of publication status or language. Non-randomized studies are included in explorative analyses. Trials will be identified through bibliographies, correspondence with original investigators, and electronic searches (Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Controlled Trials Register, MEDLINE, EMBASE, and The Chinese Biomedical Database).

METHODS OF THE REVIEW

The extracted data will include characteristics of trials, patients, interventions, and all outcome measures. Methodological quality will be assessed by the randomization, follow up, and blinding. The RevMan and STATA will be used for statistical analyses. Sources of heterogeneity and methodological quality in the assessment of the primary outcome will be explored by sensitivity analyses and meta-regression.

The liver and lovastatin

The cholesterol-lowering agents, known as statins, have been in use for 15 years and are among the most commonly prescribed drugs. Animal studies and premarketing clinical trials have given signals of hepatotoxicity, primarily minor elevations in serum alanine aminotransferase enzyme (ALT) levels. For that reason, all of the cholesterol-lowering drugs have labeling that requires monitoring of liver enzymes. Postmarketing experience, however, suggests that hepatotoxicity is rare and thus it is timely to revisit the issue. The first of the statins, lovastatin, was approved in 1986 and has acquired 24 million patient-years of clinical experience. Minor elevations in liver enzymes, i.e., ALT 3 x the upper limit of normal (ULN) occur in 2.6% and 5.0% of patients on lovastatin doses of 20 and 80 mg/day, respectively. These elevations are reversible with continuing therapy, are dose related, and are probably related to cholesterol lowering per se. Rare cases of acute liver failure (ALF) have been reported with all of the cholesterol-lowering drugs. With lovastatin, the rate is approximately 1/1.14 million patient-treatment years, which is 9% of the background rate of all causes of ALF and approximately equal to the background rate of idiopathic ALF. Monitoring for hepatotoxicity has not been effective in preventing serious liver disease, largely because of its rarity and the poor predictive value of minor ALT elevations. In fact, it may increase patient risk because of needless discontinuation of cholesterol-lowering therapy for false-positive results in patients who are benefiting from treatment.

Macrophage migration inhibitory factor in drug-induced liver injury: a role in susceptibility and stress responsiveness

Idiosyncratic drug-induced hepatitis may depend upon many factors including a balance between pro- and anti-inflammatory mediator production levels. Using a guinea pig model of liver injury induced by bioactivation of the anesthetic drug, halothane, we found that toxicity was commensurate with an increase in serum macrophage migration inhibitory factor (MIF), a pro-inflammatory signal and counter-regulator of glucocorticoids, but only in susceptible animals. The pathogenic role of MIF was further investigated using a murine model in which liver injury was induced by the reactive metabolite of another drug, acetaminophen (APAP). MIF leakage from the liver into the sera preceded peak increases in toxicity following APAP administration. MIF null (-/-) mice were significantly less susceptible to this toxicity at 8 h. At 48 h following a 300 mg/kg dose, complete lethality was observed in wild-type mice, while 46% survival was noted in MIF-/- mice. The decreased hepatic injury in MIF-/- mice correlated with a reduction in mRNA levels of interferon-gamma and a significant increase in heat shock protein expression, but was unrelated to the APAP-protein adduct formation in the liver. These findings support MIF as a critical pro-toxicant signal in drug-induced liver injury with potentially important and novel effects on heat shock protein responsiveness.