Liver transplantation for acute liver failure: outcome analysis

Predictors of progression into acute-on-chronic liver failure from acute deterioration of pre-existing chronic liver disease

AIM

To compare the prognosis between the patients with progression into acute-on-chronic liver failure (ACLF) from acute deterioration of pre-existing chronic liver disease and patients without this progression, and to determine predictors of this disease progression.

METHODS

We retrospectively analyzed clinical data from 285 patients admitted with acute worsening of pre-existing chronic liver disease within 4 weeks characterized by total bilirubin (TBIL) of 51 μM/L or more and prothrombin activity (PTA) of more than 40% but less than 70%, which did not meet the Asia-Pacific Association for the Study of the Liver criteria for ACLF. Patient survival was estimated by Kaplan-Meier analysis and subsequently compared by log-rank test. Independent predictors of disease progression were determined using univariate analysis and multivariate Cox regression analysis.

RESULTS

The 90-day survival rates significantly worsened in patients with progression into ACLF compared with those without this progression. Baseline TBIL, baseline Model for End-Stage Liver Disease (MELD) score, and the maximum changing rates of PTA level and Child-Turcotte-Pugh (CTP) score were independently associated with progression into ACLF in patients with acute deterioration of pre-existing chronic liver disease.

CONCLUSION

Patients with acute worsening of pre-existing chronic liver disease characterized by TBIL of 51 μM/L or more and PTA of more than 40% but less than 70% should receive aggressive prediction and prevention of ACLF development. Baseline TBIL, baseline MELD score, and the maximum changing rates of PTA level and CTP score may early predict the progression into ACLF.

Outcomes after living donor liver transplantation for acute liver failure in Japan: results of a nationwide survey

Nationwide surveys of acute liver failure (ALF) are conducted annually in Japan, and 20% of patients with ALF undergo liver transplantation (LT). We extracted data for 212 patients who underwent LT for ALF from the nationwide survey database of the Intractable Liver Diseases Study Group of Japan. After the exclusion of 3 patients who underwent deceased donor LT, 209 recipients of living donor liver transplantation (LDLT) were analyzed. ALF patients were placed into 3 subgroups according to the time from the onset of the disease to the occurrence of encephalopathy: patients who presented with encephalopathy within 10 days of the disease's onset were classified as having acute ALF, patients who presented within 11 to 56 days were classified as having subacute ALF, and patients who presented within 9 to 24 weeks were classified as having late-onset hepatic failure (LOHF). Long-term follow-up data were obtained from the registry of the Japanese Liver Transplantation Society. The 2 data sets were merged, and descriptive and survival data were analyzed. A Cox regression analysis was performed to define factors predicting overall mortality, short-term mortality (≤90 days after LT), and long-term mortality (>90 days after LT). One hundred ninety of the analyzed patients (91%) were adults (age ≥ 18 years); 70 patients (34%) were diagnosed with acute ALF, 124 (59%) were diagnosed with subacute ALF, and 15 (7%) were diagnosed with LOHF. Hepatitis B virus was the most common cause of acute ALF (61%), whereas autoimmune hepatitis (14%) and drug allergy-induced hepatitis (14%) were more frequent in patients with subacute ALF or LOHF. The cumulative patient survival rates 1, 5, and 10 years after LT were 79%, 74%, and 73%, respectively. Patient age was associated with short- and long-term mortality after LT, whereas ABO incompatibility affected short-term mortality, and donor age affected long-term mortality. In conclusion, the long-term outcomes of LDLT for ALF in this study were excellent, regardless of the etiology or classification. The majority of the donors were living donors. Increasing the deceased donor pool might be an urgent necessity.

Efficacy of short-term dexamethasone therapy in acute-on-chronic pre-liver failure

AIM

  Acute-on-chronic pre-liver failure (pre-ACLF) is defined as a severe acute episode of chronic hepatitis B characterized by serum bilirubin of 171 µmol/L or more, alanine aminotransferase of five times or more the upper limit of normal and prothrombin activity of more than 40%, having a potential for progression to acute-on-chronic liver failure (ACLF). This study is to evaluate the efficacy of short-term dexamethasone in pre-ACLF.

METHODS

  One hundred and seventy patients were assigned to dexamethasone therapy and control group at a ratio of 1:2. For the two groups, we compared biochemical indicators, the incidence of ACLF and mortality. The influential factors on the mortality of patients with pre-ACLF were studied by Cox proportional hazards models.

RESULTS

  The significantly lower incidence of ACLF and higher survival rate were observed in patients on dexamethasone therapy (8.9%, 96.4%, respectively) than in control patients (70.2%, 52.6%, respectively; P < 0.001). Dexamethasone treatment was an independent factor influencing the survival rate (P < 0.001, odds ratio = 0.055, 95% confidence interval = 0.013-0.225). During 4 weeks of treatment, serum bilirubin levels of survival patients were significantly lower in the dexamethasone group than control group.

CONCLUSION

  Five-day dexamethasone therapy is effective in improving the liver function and survival rate of patients with pre-ACLF.

Serum alpha-NH-butyric acid may predict spontaneous survival in pediatric acute liver failure

ALF is a serious, often fatal condition. Up to half of PALF patients do not survive without liver transplantation; however, early identification of those least likely to survive spontaneously remains difficult. Clinical experience suggests that recovery from ALF depends on the ability of the liver to regenerate. Based on this, we hypothesized that bio-markers of hepatic regeneration could have utility as predictors of recovery from PALF. In the studies reported here, we used comprehensive amino acid analysis to search for novel metabolomic markers of liver regeneration in mice subjected to partial hepatectomy. This analysis identified alpha-NH(2)-adipic acid and alpha-NH(2)-butyric acid as significantly increased in liver and plasma samples from mice subjected to partial hepatectomy compared to controls. Next, we tested whether serum levels of these markers were associated with clinical outcomes in PALF patients. This examination, performed on the initially collected serum samples from 40 randomly selected patients enrolled in the PALF Study Group, showed increased alpha-NH(2)-butyric-acid (Aab) and Aab:leucine (Aab:Leu) ratio in patients who survived without transplantation compared to those who were transplanted or died. These data indicate that Aab and the Aab:Leu ratio may predict clinical outcomes in PALF.

[Acute liver failure]

Acute liver failure is characterized by a dynamic clinical course associated with high mortality. The main prognostic determinant is the development of extrahepatic complications. Close monitoring is mandatory, and prophylactic measures to avoid complications should be initiated. In case of complications, early and aggressive treatment is indicated. To date, artificial liver support devices are still in the experimental phase. Liver transplantation should be considered in patients with predictors of a poor spontaneous prognosis. Therefore, a transplant center should be contacted in every case of acute liver failure.

Inhibition of caspase activity prevents CD95-mediated hepatic microvascular perfusion failure and restores Kupffer cell clearance capacity

Using a murine model, we studied the effect of agonistic anti-CD95 antibodies (aCD95) on sinusoidal lining cells and a potential protection by caspase inhibition. C3H/HeN mice were intravenously administered aCD95 (10 microgram/mouse) or unspecific IgG (control) in the presence or absence of the caspase inhibitor z-VAD-fmk. Analysis of hepatic microcirculation using intravital fluorescence microscopy revealed severe (P<0.01) sinusoidal perfusion failure and reduced (P<0.05) phagocytic activity of Kupffer cells (KC) within 2 h. Transmission electron micrographs demonstrated loss of integrity of sinusoidal endothelial cells as early as 1 h after aCD95 application, whereas histological manifestation of hepatocellular apoptosis and hemorrhagic necrosis was most pronounced at 6 h. Blocking of caspase activity attenuated (P<0.01) both hepatic microvascular perfusion failure and KC dysfunction. Accordingly, full protection of the liver from apoptotic damage and intact microarchitecture was observed in histological sections after z-VAD-fmk treatment. Mortality rate was 40% 6 h after aCD95 administration, whereas all animals survived in the z-VAD-fmk group (P<0.05). The activation of caspases through CD95 may primarily lead to damage of sinusoidal endothelial cells and hepatic microvascular perfusion failure. Moreover, reduced phagocytic capacity of KC may contribute to accumulation of toxic metabolites released by dying cells at the local site of inflammation, further aggravating liver injury.