The effects of early and late administration of inhibitors of inducible nitric oxide synthase in a thioacetamide-induced model of acute hepatic failure in the rat

BACKGROUND/AIMS

Nitric oxide (NO) is a pivotal mediator of inflammation. Its role in acute hepatic failure (AHF) is controversial. We investigated the role of NO, and the hypothesis that inhibition of inducible NO synthase (iNOS) activity would improve outcome in liver failure in rats, using the iNOS inhibitors L-NAME and aminoguanidine (AMG).

METHODS

AHF was induced by two intraperitoneal injections of thioacetamide (TAA). Seven groups (n=10) were studied. Group I: TAA alone. Groups II, III and IV were additionally pre-treated with the NO precursor L-arginine (300 mg/kg i.p.), or iNOS inhibitors AMG (100 mg/kg s.c.), or N(G)-nitro-L-arginine methyl ester (L-NAME) (100 mg/kg s.c.) for 5 days, respectively. Groups V, VI and VII received L-arginine, AMG or L-NAME commencing immediately after TAA administration. Clinical and biochemical parameters were assessed serially, and mortality investigated in further similar cohorts for each regime.

RESULTS

AMG, pre-treatment but not post-treatment, significantly improved outcome including mortality (10 vs. 70%, P<0.005). The less selective iNOS inhibitor L-NAME was not beneficial. Arginine pre-and post-treatment, and iNOS inhibition post-treatment, worsened clinical parameters of TAA-induced liver failure.

CONCLUSIONS

Administration of the iNOS inhibitor AMG prior to insult reduces the severity of damage and improves mortality.

Economic evaluation of MARS--preliminary results on survival and quality of life

OBJECTIVES

The short-term medical benefit of the liver dialysis system MARS in patients with severe acute liver disease has clearly been demonstrated. An economic analysis of MARS has not been presented previously. Objective of the study is to calculate the costs per life saved and life year gained and to measure health related quality of life in patients who survived acute liver failure. First results on survival and HRQL are presented here.

STUDY DESIGN

Cost effectiveness and cost utility analysis of MARS are performed. All patients since 1993 with chronic liver failure (Bilirubin > 300 micro mol/l) of the university hospital Rostock are included in the original sample (n = 141). Survival data are calculated. Surviving patients were contacted personally, thus quality of life data (EQ 5D and SF12) determined. Patients were compared in case control study design. In a later stage inpatient hospital costs, direct and indirect outpatients costs are included in the analysis.

PRELIMINARY RESULTS

MARS-Patients show a higher survival: Kaplan-Meier cumulative survival after 100 days: 0.59 after MARS, 0.39 without (P <0.05). There was no significant difference in health related quality of life (SF12 and EQ-D). Calculations of quality adjusted life years (QALYs) result in 0.116 QALYs gained by treatment of one patient with MARS in one year.

DISCUSSION

First preliminary results suggest that 1 year after therapy MARS seems to have a positive effect concerning survival rate, survival time and QALYs gained. Final results of cost-effectiveness and cost-utility analysis will soon be presented.

The Molecular Adsorbent Recirculating System in patients with severe liver failure: clinical results at the K.U. Leuven

BACKGROUND

The Molecular Adsorbent Recirculating System (MARS) is a novel extracorporeal technique for liver support. We report the clinical results in the first 13 patients with severe liver failure treated at our institution.

METHODS

Patients with acute or acute on chronic liver failure of various aetiologies were treated with varying numbers of MARS sessions of six hours duration.

RESULTS

Mean APACHE II score was 18. In general, patients with multiple organ failure faired poorly even with MARS treatment. Five patients (38%) survived the hospitalisation. Eight patients (62%) fulfilled criteria for UNOS type I or 2 A status. Two of these patients survived. Five patients had a UNOS 2B status and three survived. In proportion, patients with severe itch, patients with primary non-function and those where MARS was used as a bridge to transplantation seemed to profit most from the treatment. The median reduction in bilirubin concentrations after the treatment period was -28.2%. In survivors, the median reduction was -37.7% and in patients who died was -15.9%. The median encephalopathy score improved from 1.7 to 0.5.

CONCLUSION

The molecular adsorbent recycling system (MARS) might be lifesaving in patients with severe liver failure of different aetiologies.

The development of a new bioartificial liver and its application in 12 acute liver failure patients

AIM: Bioartificial liver is a hope of supporting liver functions in acute liver failure patients. Using polysulfon fibers, a new bioartificial liver was developed. The aim of this study was to show whether this bioartificial liver could support liver functions or not.

METHODS: Hepatocytes were procured from swine using Seglen’s methods. The bioartificial liver was constructed by polysulfon bioreactor and more than 10¹⁰ hepatocytes. It was applied 14 times in 12 patients, who were divided into 7 cases of simultaneous HBAL and 5 cases of non-simultaneous HBAL. Each BAL treatment lasted 6 hours. The general condition of the patients and the biochemical indexes were studied.

RESULTS: After treatment with bioartificial liver, blood ammonia, prothrombin time and total bilirubin showed significant decrease. 2 d later, blood ammonia still showed improvment. within one month period, 1 case (1/7) in simultaneous group died while in non-simultaneous group 2 cases (2/5) died. The difference was significant. Mortality rate was 25%.

CONCLUSION: The constructed bioartificial liver can support liver functions in acute liver failure. The simultaneous HBAL is better than non-simultaneous HBAL.

The effects of supraphysiological doses of corticosteroids in hypotensive liver failure

BACKGROUND

In septic shock, supraphysiological doses of corticosteroids reduce norepinephrine requirements. We reviewed our experience of this treatment in hypotensive liver failure.

METHODS

We retrospectively analysed 20 patients with liver failure who were treated with supraphysiological doses of hydrocortisone because of norepinephrine dependence. We compared their norepinephrine requirements, outcome, microbiology and incidence of gastrointestinal bleeding to an historical control group treated with norepinephrine but not corticosteroids.

RESULTS

After 48 h of steroid treatment, the median norepinephrine dose was reduced (0.14 microg/kg/min to 0.08 microg/kg/min; P < 0.05) while the blood pressure over the same period of time did not change significantly (67.3 mm Hg to 70 mm Hg). Duration of ITU stay was longer in the steroid treated group (13.5 days vs 3 days; P < 0.05) but survival was similar in both groups. There were 23 episodes of positive bacterial cultures after norepinephrine was started in the steroid treated group, compared with 18 episodes in the control group. More of the positive cultures were due to resistant organisms in the steroid treated group (65% vs 17% in the control group; P < 0.002). There was no significant bleeding due to gastrointestinal inflammation in either group.

CONCLUSIONS

Supraphysiological doses of corticosteroids reduce norepinephrine requirements in hypotensive liver failure. They do not improve survival but may extend time to find a suitable donor in those awaiting urgent liver transplantation.

The development of a new bioartificial liver and its application in 12 acute liver failure patients

AIM

Bioartificial liver is a hope of supporting liver functions in acute liver failure patients. Using polysulfon fibers, a new bioartificial liver was developed. The aim of this study was to show whether this bioartificial liver could support liver functions or not.

METHODS

Hepatocytes were procured from swine using Seglen's methods. The bioartificial liver was constructed by polysulfon bioreactor and more than 10(10) hepatocytes. It was applied 14 times in 12 patients, who were divided into 7 cases of simultaneous HBAL and 5 cases of non-simultaneous HBAL. Each BAL treatment lasted 6 hours. The general condition of the patients and the biochemical indexes were studied.

RESULTS

After treatment with bioartificial liver, blood ammonia, prothrombin time and total bilirubin showed significant decrease. 2 days later, blood ammonia still showed improvment. within one month period, 1 case (1/7) in simultaneous group died while in non-simultaneous group 2 cases (2/5) died. The difference was significant. Mortality rate was 25 %.

CONCLUSION

The constructed bioartificial liver can support liver functions in acute liver failure. The simultaneous HBAL is better than non-simultaneous HBAL.

Hyaluronic acid and endothelial damage due to paracetamol-induced hepatotoxicity

BACKGROUND

Damage to endothelial cells may be an important factor in the complications of acute liver failure, resulting in multi-organ failure. The aim of this study was to assess endothelial cell function in patients with severe hepatotoxicity due to paracetamol ingestion.

PATIENTS AND METHODS

Fifty-eight patients with paracetamol-induced hepatotoxicity were studied for up to 7 days. Serum hyaluronic acid (HA), as a marker of hepatic sinusoidal endothelial cell function, was determined using an enzyme-linked binding assay. Plasma von Willebrand Factor, thrombomodulin and interleukin-8 were also determined using ELISA.

RESULTS

Serum HA on admission was significantly increased (median 6777 ng/ml, range 24-50 967 ng/ml) as compared to normal controls (n = 10, median 21 ng/ml, range 0-50 ng/ml; P < 0.001). In non-survivors (n = 21) HA levels peaked on day 2 after admission (P = 0.044), and then decreased. In the survivors (n = 37) the levels of HA did not increase further. Plasma von Willebrand Factor, plasma thrombomodulin and serum interleukin-8 were significantly increased in the patients as compared to the normal controls (P < 0.001). Serum interleukin-8 was significantly higher in non-survivors in the first 2 days.

CONCLUSIONS

Endothelial function is abnormal in paracetamol-induced hepatotoxicity. Damage to hepatic sinusoidal endothelial cells assessed by serum HA was greater in non-survivors than survivors.

Orthotopic liver transplantation in patients with human immunodeficiency virus and end-stage liver disease

Patients with human immunodeficiency virus (HIV) most often have hepatitis C virus (HCV) or hepatitis B (HBV) virus coinfection, or both, as a cause of their liver disease. Recent survival statistics show that patients infected with HIV treated with highly active antiretroviral therapy (HAART) can expect a significant prolongation of life by interfering with the natural progression of HIV to acquired immune deficiency syndrome (AIDS). Therefore, HIV-positive patients experiencing complications of liver failure are at greater immediate risk of dying from their end-stage liver disease (ESLD) rather than their HIV. Many transplant centers still consider HIV infection as a contraindication for orthotopic liver transplantation (OLT). At our two institutions, we believe that patients with HIV suffering from ESLD should be considered for OLT. This study evaluates the survival of patients undergoing OLT with HIV under HAART therapy. OLT was performed in 16 patients with HIV suffering from ESLD as a result of chronic HCV, chronic HBV, or fulminant hepatic failure (FHF). Collected data include patient demographics, patient and graft survival, pre-OLT assessments, and postoperative complications (including opportunistic infections). Ten patients at Pittsburgh and 6 patients at Miami received OLT. Of the 16 patients who received OLT, 14 remain alive to date. Thirteen of 16 patients are more than 12 months post-OLT, whereas the last patient is currently 6 months post-OLT. Five patients at Miami and 9 of 10 patients at Pittsburgh received HAART therapy before OLT, although 2 of the Pittsburgh patients had their HAART therapy discontinued before OLT because of significant liver dysfunction. The pre-OLT viral loads were undetectable in 13 of 16 patients. The cluster determinant (CD)4 count was less than 200 in 6 patients and greater than 100 in 2 patients before OLT. In all patients, CD4 counts increased above 200 in the post-OLT period. Tacrolimus toxicity associated with the pharmacologic inhibition of cytochrome p450 metabolism caused by protease inhibitors occurred in 6 patients after OLT. Six patients (38%) experienced acute cellular rejection immediately after OLT. Our experience suggests that OLT is effective in selected HIV-positive patients suffering from ESLD. Patient and graft survival was similar to non-HIV-positive patients suffering from the same indications for OLT. Acute cellular rejection was no less frequent that seen in non-HIV-positive patients. Given the complex pharmacologic interactions between the protease inhibitors and tacrolimus, careful monitoring, and attention is required to prevent toxicity or underdosing.

Viral hepatitis-related acute liver failure

OBJECTIVES

Viral hepatitis has previously been the major cause of acute liver failure (ALF) in the United States. We aimed to determine the incidence of viral hepatitis-related ALF and to compare the outcome and clinical and biochemical variables in patients with hepatitis A and B.

METHODS

A total of 354 patients with ALF from multiple centers were screened for possible acute viral etiology.

RESULTS

Forty-three patients (12.1% of all ALF cases) had acute viral hepatitis: hepatitis A (n = 16), hepatitis B (n = 26), and herpes simplex virus infection (n = 1). There was no difference between groups with regard to age, gender, body mass index, admission or peak coma grade, symptom duration, admission mean arterial pressure, temperature, or biochemical liver tests, creatinine, arterial pH, or rate of infections. Platelet count was significantly higher in hepatitis A patients than in hepatitis B patients. The transplantation-free (spontaneous) survival rate was significantly higher for hepatitis A patients (69%) than for hepatitis B patients (19%, p = 0.007), whereas the liver transplantation rate was higher in hepatitis B patients (62%) than in hepatitis A patients (19%, p = 0.017). Spontaneous survivors had significantly higher mean arterial pressure, higher platelet count, and lower AST/ALT ratio than patients who did not survive spontaneously.

CONCLUSIONS

Viral hepatitis now comprises only one-eighth of all ALF cases in the United States. The marked difference in spontaneous survival between hepatitis A and B cannot be explained by the severity of hepatic dysfunction on admission but may rather be an inherent feature of the infections or a bias toward transplanting patients with hepatitis B.

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.

Auxiliary partial orthotopic liver transplantation (APOLT) in the treatment of acute liver failure

BACKGROUND

Auxiliary partial orthotopic liver transplantation (APOLT) has been developed in order to benefit from the efficacy of orthotopic liver transplantation (OLT) in the treatment of fulminant hepatic failure (FHF), but to avoid the negative counterpart of OLT which is to eliminate the possibility of native liver (NL) regeneration and which consequently implies a life-long immunosuppression.

METHODS

In our institution we performed 16 consecutive APOLTs in 15 patients between October 1992 and December 1999. Patients' mean age was 30 years (range 0.5-65 years). The causes of FHF were viral (HAV = 3; HBV = 3), drugs (n = 4), or others (n = 5). None of the patients had a history of chronic liver disease. The decision to transplant was taken when the patients met well-defined criteria. All but one of the patients were in a coma.

RESULTS

Five patients died, 10 patients are alive (66.7%). Regeneration of the NL occurred in 11 of the 15 patients (73.3%) and in 8 of the 10 survivors. Six of these 8 patients have permanently stopped immunosuppressive therapy. These results can be favorably compared with those of OLT for FHF. In the European Transplant Registry, the survival rate is 57% at 5 years (2612 patients receiving OLT for FHF between 1988 and 1998). In our experience the survival rate is 59% at 5 years (42 patients receiving OLT for FHF between 1987 and 1999).

CONCLUSIONS

APOLT is feasible in both adults and children; it rapidly restored liver function and reversed encephalopathy. Right APOLT seems more advisable since the right liver provides more functional hepatocytes; however, left APOLT harvested in an adult appears sufficient for a child. APOLT should be proposed only to patients with high chances of liver regeneration: age of recipient, etiology of liver failure, interval between onset of jaundice and occurrence of encephalopathy, and quality of liver graft are early prognostic indicators. Better results have been observed with younger patients (less than 40 years old) presenting with FHF (rather than subfulminant hepatic failure (SHF)) and due to HAV, HBV, or paracetamol.

Glycine conjugation of para-aminobenzoic acid (PABA): a pilot study of a novel prognostic test in acute liver failure in children

BACKGROUND

Fulminant hepatic failure (FHF) is associated with high mortality; few patients survive without liver transplantation. It is important to have a sensitive, specific early predictor of outcome to distinguish potential survivors (S) from nonsurvivors (NS).

OBJECTIVE

Because we had previously shown that glycine conjugation of para-aminobenzoic acid (PABA) quantitatively reflects liver function in children with chronic liver disease, in this pilot study we wanted to determine whether the measurement of the glycine conjugates of PABA could distinguish S from NS in FHF in comparison with standard prognostic indices.

METHODS

Twenty-four patients were studied: acute severe hepatitis (n = 7), subfulminant hepatic failure (n = 7), and FHF (n = 10). Assessment of King's College criteria, measurement of factor V and VII levels, PABA testing, and transjugular liver biopsies were performed in almost all patients within 48 hours of admission. Serum PABA and its glycine conjugates (para-aminohippurate (PAHA) and para-acetamidohippurate (PAAHA)) were measured thirty minutes after oral administration by high-pressure liquid chromatography. Poor prognostic categories as previously established in the literature were defined as factor V < 0.20U/ml, factor VII < 0.08 U/ml, % necrosis >70%, hippurate ratio = 0%, and PAHA = 0M.

RESULTS

The measurement of PAHA was the best predictor of a poor outcome in patients with acute liver failure with a sensitivity of 92%, and negative predictive value (NPV) of 92% compared with a sensitivity of 54% and a NPV of 63% with King's College criteria.

CONCLUSION

Measurement of serum PAHA is the best early prognostic marker of death in children who suffer from FHF.

Acute liver failure

Acute liver failure in children is associated with a high mortality. Most cases in our setup are due to water borne hepatotropic viruses HAV and HEV. The clinician must be aware of the earliest and the subtle signs of acute liver failure to identify cases early enough and institute supportive therapy. Focus of therapy has to be on prevention, early recognition and appropriate management of complications. Despite good intensive care, about 40-60% children with liver failure die. As and when liver transplantation becomes available in India, it would be an attractive option.

Characterization of treatment dose delivered by albumin dialysis in the treatment of acute renal failure associated with severe hepatic dysfunction

BACKGROUND

Acute liver cell failure (ALCF) commonly results in death and when complicated by acute renal failure (ARF), the mortality approaches 90%. Albumin dialysis allows partial replacement of some of the liver's excretory functions. The molecular absorbents recirculating system (MARS) has been recently introduced to provide this therapy. Thus allowing bridging to transplantation or hepatic regeneration. We have attempted to define the degree of "uremic" dialysis that this system can deliver as well as characterizing the dose of "hepatic" treatment, using a similar approach to solute remove as applied to assessing hemodialysis adequacy. As a secondary issue we also report on the clinical outcomes of this group of patients.

METHOD

We treated 7 patients with ALCF and acute renal failure (6 of the patients having a formal diagnosis of hepatorenal syndrome), aiming to deliver a 5 treatment consecutive course consisting of 8 hours of albumin dialysis using the MARS monitor, combined with hemodialysis. Clinical and biochemical outcomes were assessed, and dialysis adequacy measured using urea reduction ratios, calculated Kt/V and measured Kt/V (using ionic dialysance). Treatment dose, with respect to the highly protein bound and lipophilic toxins that accumulate in hepatic failure, was assessed by calculating the bilirubin reduction ratio and percentage reduction in plasma ammonia and total bile acids.

RESULTS

All of the patients had a degree of biochemical improvement with albumin dialysis. Urine output increased and the degree of encephalopathy improved. Mean bilirubin fell from 612 +/- 105.5 micromol/l (range 165.6 - 1,024 micromol/l) to 370.4 +/- 49.7 micromol/l (range 190.4 - 569.2 micromol/l), ALT reduced from 3,280 +/- 2,266 IU/l (range 40 - 18,876) to 639 +/- 230 IU/l (range 33 - 1677). Hepatic synthetic function improved with INR falling from 4.1 +/- 0.5 (range 2.1 - 6.4) to 2.8 +/- 0.6 (range 1.4 - 5.5). Plasma ammonia was reduced, falling from 162.4 +/- 15.4 (range 131.1 - 191.9 micromol/l) to 73.1 +/- 15 micromol/l (range 45.6 - 106.4 micromol/l). Bile acid levels fell from 132 +/- 10.2 micromol/l (range 110.7 - 155.8 micromol/l) to 36.9 +/- 6.1 micromol/l (range 24.6 49.6 micromol/l). The mean urea reduction ratio (URR) was 58.4 +/- 3.2% (range 39 - 76%). Mean Kt/V as assessed by ionic dialysance was 1.7 +/- 0.01 (range 0.8-2.4). Mean bilirubin reduction ratio (BRR) was 28.6 +/- 1.4% (range 12.5 - 39%). BRR was proportional to both URR and Kt/V. BRR was also proportional to the percentage reduction of ammonia and bile acid levels. Three of the 7 patients survived to be discharged from hospital and 4 died.

CONCLUSION

Albumin dialysis appears capable of improving the outcome in patients with ALCF and hepatorenal syndrome. Eight-hour intermittent treatments with the MARS system in combination with hemodialysis deliver an adequate dose of dialysis with respect to urea. BRR may be an appropriate tool to allow further quantitative and comparative study of this technique.

Prospective surveillance of acute serious liver disease unrelated to infectious, obstructive, or metabolic diseases: epidemiological and clinical features, and exposure to drugs

BACKGROUND/AIMS

Acute serious liver disease which is unrelated to infectious, obstructive, or metabolic disease is uncommon. Many drugs have been implicated. Data on its epidemiology are scarce. We performed a population-based prospective study of acute serious liver disease in Catalonia (Spain).

METHODS

A collaborating hospital network was set up. All patients with acute serious liver disease and negative viral hepatitis serological markers, without an obvious cause of liver disease, were included.

RESULTS

The incidence of acute serious liver disease was 7.4 per 10(6) inhabitants per year (95% CI; 6.0-8.8), which increased with age. The incidence of hepatocellular acute serious liver disease (3.84 per 10(6) per year) was greater than that of cholestatic and mixed patterns. The case-fatality ratio was 11.9% and mortality 0.8 per million person-years. The risk of death was similar among patients with hepatocellular and cholestatic patterns. Non-steroidal antiinflammatory drugs, analgesics, and antibacterials were the most frequently used drugs.

CONCLUSIONS

Acute serious liver disease which is unrelated to infectious, obstructive, or metabolic disease is rare. Its incidence increases with age. The prognosis of cholestatic acute serious liver disease does not significantly differ from that of the hepatocellular pattern. Non-steroidal antiinflammatory drugs, analgesics, and antibacterials were the most common drugs likely to be responsible for acute liver disease.

Development of a new bioartificial liver using a porcine autologous biomatrix as hepatocyte support

Long-term maintenance of hepatocyte viability and differentiated function expression is crucial for bioartificial liver support. The maintenance of hepatocyte function in a bioreactor is still a problem. A major advance was the recognition that hepatocytes in attachment cultures can maintain their differentiation longer. To restore hepatocyte polarity and prolong their function, we developed a new bioreactor with a cross-flow geometry configuration and an original hepatocyte extracellular autologous biomatrix (Porcine Bio-Matrix) support. To test this new bioreactor, we compared it with a standard bioartificial liver cartridge in a suitable surgical model of acute liver failure in pigs. In our model, we performed a total hepatectomy, followed by partial liver transplantation after an 18 hour anhepatic phase. The results showed that the bioreactor containing the biomatrix was able to bridge the animal to transplantation and to sustain the transplanted liver until all function recovered (80% of animals survived, p = 0.0027). No animal survived more than 24 hours after liver transplantation in the group treated with the traditional bioartificial liver, whereas hepatocyte viability on the Porcine Bio-Matrix was 65% after 12 hours of treatment. The results suggest that our biomatrix is a suitable cell support and guarantees long-term maintenance of metabolic activity of hepatocytes. Further studies are needed, but the results obtained with this new three-dimensional bioreactor are promising, and its potential is attractive.

Clinical outcome of orthotopic liver transplantation

Orthotopic liver transplantation (OLT) has become a standard procedure for end-stage cirrhosis. The purpose of this anlysis is to give a brief overview on the clinical outcome of OLT. According to a current survey of primary indications for liver transplantation in Europe, virus-induced cirrhosis represents the largest proportion with 25%. The next frequent indication is alcoholic cirrhosis with 19%. Cholestatic diseases amount to 13%, malignancy in cirrhosis 10%, and acute hepatic failure 10%. The outcome of these main indications will be discussed and critical considerations pointed out. Patient survival rates demonstrate for cirrhosis at 1-and 5-year about 80% and 70%, respectively. In acute hepatic failure, more patients are lost in the perioperative period. Not surprisingly, patients transplanted for malignancy show decreased long-term survival. Considering an average of 5-year survival in patients with end-stage liver disease of 20% or less, excellent patient survival can be achieved by liver transplantation.

[Acute hepatic failure in a teaching hospital: a review of 20 cases in the past seven years]

Acute liver failure (ALF) is a medical emergency which entails a multisistemic affectation almost always. Twenty cases of ALF have been reviewed in a teaching hospital with active liver transplantation programme. A high percentage of patients with alcohol abuse was observed although these patients did not have previously known hepatic damage. Although microbiological, toxicological and anatomopatological studies were performed in all cases, an important difficulty for establishing the etiologic agent was observed. We observed a worse prognosis in those patients older than 40, those with grade IV encephalophaty and those that did not undergo a liver transplantation. Most patients needed UCI attention and more than half died.

Temporary support for acute liver failure

GOAL

To review treatment approaches for temporary liver support of patients with acute liver failure (ALF). STUDY A MEDLINE: search of English language reports published between 1960 and 1999 and a manual search of bibliographies of relevant papers were performed. Studies of humans in whom non-orthotopic liver transplant (OLT)-based approaches were used were reviewed, including case reports, case series, review articles describing unpublished cases, and controlled trials. Relevant clinical information was extracted with emphasis on improvement in liver function, successful bridging to OLT, recovery without OLT, and death. There was a lack of more than one controlled trial for each therapy, and most case reports were anecdotal in nature; therefore, no statistical analysis was attempted. Predefined outcomes from individual patients were synthesized collectively into tables.

RESULTS

Both cell-based and non-cell-based therapies for ALF appear promising. Preliminary experience has established the safety of these approaches, but current data are inadequate to evaluate efficacy.

CONCLUSIONS

Routine use of artificial liver support systems cannot be recommended at this time. However, the established safety of cell- and non-cell-based liver support devices warrants additional prospective (Phase III) controlled trials among patients with ALF. We suggest an algorithm for management of patients with ALF that incorporates recent data.

Etiology and outcome of acute liver failure: experience from a liver transplantation centre in Montreal

BACKGROUND

Acute liver failure is a rare condition in which massive liver injury is associated with the rapid development of hepatic encephalopathy. Although viral hepatitis and drug-induced liver injury are the most common causes, no specific etiology is found in a substantial proportion of cases reported from Europe and the United States.

AIM

To determine the etiology and outcome of patients with acute liver failure in the authors' institution.

PATIENTS AND METHODS

The charts of 81 consecutive patients admitted to Saint-Luc between 1991 and 1999 were reviewed.

RESULTS

The etiology was viral in 27 cases (33.2%), toxic or drug-induced in 22 (27.2%), of unknown origin in 22 (27.2%) and due to various causes in 10 (12.3%) (autoimmune, vascular, cancer). Of the 81 patients, 16% survived without liver transplantation, and 84% died or underwent liver transplantation. Survival without liver transplantation differed according to the mode of presentation: the survival rate was 27% in patients with hyperacute liver failure, 7% in those with acute liver failure and 0% in those with subacute liver failure. Among the 38 patients who underwent liver transplantation, survival one year after transplantation was 71%. In the 30 patients who died without liver transplantation, the main causes of death were cerebral edema and sepsis.

CONCLUSIONS

Acute liver failure is associated with a high mortality, and liver transplantation is the treatment of choice. In a significant proportion of cases, the etiology remains undetermined and is probably related to yet unidentified hepatotropic viruses.

Acute liver failure in children: observations in Vitória, Espírito Santo State, Brazil

In this communication we report 46 cases of acute liver failure in children diagnosed at the Hospital Infantil Nossa Senhora da Glória in Vitória, E Santo. Serology for IgM anti-HAV, IgM anti-HBc, HbsAg, anti-HCV and biochemical tests were performed in all cases in a routine laboratory. The M/F ratio was 1.1:1 and the mean age was 4.7 +/- 3.2 years, without gender difference. Anti-HAV IgM+ in 38 (82.6%) cases, anti-HbcIgM+ in two (4.3%) cases and 6 (13.1%) cases were negative for all viral markers investigated. Anti-HCV+ in one anti-HAV IgM+ case. HbsAg+ in two anti-HbcIgM+ and in two HAVIgM+ cases. Among the six A, B and C negative cases, four (8.6%) did not have the suspected exogenous intoxication. Mortality was 50%, without gender or age differences. These results demonstrate that HAV infection is the main etiology of acute liver failure in children in Brazil, confirming that, although it is a self limited, relatively mild illness, it can cause serious and even fatal disease. The observation of four cases without A, B and C viral markers and no history of exogenous intoxication, agree with the observation of non A-E acute sporadic hepatitis in Northeastern Brazil.

Hepatic dysfunction increases length of stay and risk of death after injury

BACKGROUND

The relative importance of dysfunction or failure of different organ systems to recovery from critical illness is unclear. The purpose of this study was to evaluate the contribution of hepatic dysfunction to outcome after injury.

METHODS

We retrospectively evaluated patients admitted to our trauma center from 1994 to 1998 for the development of hepatic dysfunction, defined as serum bilirubin > or = 2.0 mg/dL. Additional variables on patient demographics, injuries, hospital course, and development of other organ system dysfunction were collected from the trauma registry and hospital records.

RESULTS

Using logistic regression analysis, hepatic dysfunction was significantly associated with increased intensive care unit length of stay (LOS) and death. The added development of hepatic dysfunction significantly increased LOS in patients with no other organ dysfunction, those with renal dysfunction, and those with respiratory dysfunction.

CONCLUSION

Hepatic dysfunction influences recovery after injury independent of the dysfunction of other organ systems. The development of hepatic dysfunction prolongs LOS and increases mortality.