Classification, etiology, and considerations of outcome in acute liver failure

Biomolecular map of albumin identifies signatures of severity and early mortality in acute liver failure

BACKGROUND & AIMS

Acute liver failure (ALF) is associated with high mortality. Alterations in albumin structure and function have been shown to correlate with outcomes in cirrhosis. We undertook a biomolecular analysis of albumin to determine its correlation with hepatocellular injury and early mortality in ALF.

METHODS

Altogether, 225 participants (200 patients with ALF and 25 healthy controls [HC]) were enrolled. Albumin was purified from the baseline plasma of the training cohort (ALF, n = 40; survivors, n = 8; non-survivors, n = 32; and HC, n = 5); analysed for modifications, functionality, and bound multi-omics signatures; and validated in a test cohort (ALF, n = 160; survivors, n = 53; non-survivors, n = 107; and HC, n = 20).

RESULTS

In patients with ALF, albumin is more oxidised and glycosylated with a distinct multi-omics profile than that in HC, more so in non-survivors (p <0.05). In non-survivors, albumin was more often bound (p <0.05, false discovery rate <0.01) to proteins associated with inflammation, advanced glycation end product, metabolites linked to arginine, proline metabolism, bile acid, and mitochondrial breakdown products. Increased bacterial taxa (Listeria, Clostridium, etc.) correlated with lipids (triglycerides [4:0/12:0/12:0] and phosphatidylserine [39:0]) and metabolites (porphobilinogen and nicotinic acid) in non-survivors (r2 >0.7). Multi-omics signature-based probability of detection for non-survival was >90% and showed direct correlation with albumin functionality and clinical parameters (r2 >0.85). Probability-of-detection metabolites built on the top five metabolites, namely, nicotinic acid, l-acetyl carnitine, l-carnitine, pregnenolone sulfate, and N-(3-hydroxybutanoyl)-l-homoserine lactone, showed diagnostic accuracy of 98% (AUC 0.98, 95% CI 0.95-1.0) and distinguish patients with ALF predisposed to early mortality (log-rank <0.05). On validation using high-resolution mass spectrometry and five machine learning algorithms in test cohort 1 (plasma and paired one-drop blood), the metabolome panel showed >92% accuracy/sensitivity and specificity for prediction of mortality.

CONCLUSIONS

In ALF, albumin is hyperoxidised and substantially dysfunctional. Our study outlines distinct 'albuminome' signatures capable of distinguishing patients with ALF predisposed to early mortality or requiring emergency liver transplantation.

IMPACTS AND IMPLICATIONS

Here, we report that the biomolecular map of albumin is distinct and linked to severity and outcome in patients with acute liver failure (ALF). Detailed structural, functional, and albumin-omics analysis in patients with ALF led to the identification and classification of albumin-bound biomolecules, which could segregate patients with ALF predisposed to early mortality. More importantly, we found albumin-bound metabolites indicative of mitochondrial damage and hyperinflammation as a putative indicator of <30-day mortality in patients with ALF. This preclinical study validates the utility of albuminome analysis for understanding the pathophysiology and development of poor outcome indicators in patients with ALF.

Potential Probiotic Properties of Blautia producta Against Lipopolysaccharide-Induced Acute Liver Injury

Blautia is a genus of anaerobic microbe extensively present in the intestine and feces of mammals. This study aims to investigate the influence of Blautia producta to prevent lipopolysaccharide (LPS)-induced acute liver injury (ALI) and elaborate on its hepatoprotective mechanisms. B. producta D4 and DSM2950 pretreatment decreased the activities of serum aspartate transferase (AST), and alanine transaminase (ALT) in mice with LPS treatment significantly decreased the levels of inflammatory tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) and increased the activities of antioxidative superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). Compared with the model group, B. producta D4 and B. producta DSM2950 pretreatment slightly increased the levels of cecal propionic acid, isobutyric acid, butyric acid, valeric acid, and isovaleric acid (p > 0.05). Metagenomic analysis showed that B. producta D4 and DSM2950 pretreatment remarkably increased the relative abundance of [Eubacterium] xylanophilum group, Lachnospira, Ruminiclostridium, Ruminiclostridium 9, Coprococcus 2, Odoribacter, Roseburia, Alistipes, and Desulfovibrio in ALI mice, and their abundance is negatively related to the levels of inflammatory TNF-α, IL-1β, and IL-6 as revealed by Spearman's correlation analysis. Moreover, transcription and immunohistochemistry analysis revealed that B. producta D4 and B. producta DSM2950 intervention remarkably suppressed the transcription and expression levels of hepatic Tlr4, MyD88, and caspase-3 (p < 0.05). These data indicated that B. producta may be a good candidate for probiotics in the prevention of ALI.

Fulminant Viral Hepatitis in Two Siblings with Inherited IL-10RB Deficiency

Fulminant viral hepatitis (FVH) caused by hepatitis A virus (HAV) is a life-threatening disease that typically strikes otherwise healthy individuals. The only known genetic etiology of FVH is inherited IL-18BP deficiency, which unleashes IL-18-dependent lymphocyte cytotoxicity and IFN-γ production. We studied two siblings who died from a combination of early-onset inflammatory bowel disease (EOIBD) and FVH due to HAV. The sibling tested was homozygous for the W100G variant of IL10RB previously described in an unrelated patient with EOIBD. We show here that the out-of-frame IL10RB variants seen in other EOIBD patients disrupt cellular responses to IL-10, IL-22, IL-26, and IFN-λs in overexpression conditions and in homozygous cells. By contrast, the impact of in-frame disease-causing variants varies between cases. When overexpressed, the W100G variant impairs cellular responses to IL-10, but not to IL-22, IL-26, or IFN-λ1, whereas cells homozygous for W100G do not respond to IL-10, IL-22, IL-26, or IFN-λ1. As IL-10 is a potent antagonist of IFN-γ in phagocytes, these findings suggest that the molecular basis of FVH in patients with IL-18BP or IL-10RB deficiency may involve excessive IFN-γ activity during HAV infections of the liver. Inherited IL-10RB deficiency, and possibly inherited IL-10 and IL-10RA deficiencies, confer a predisposition to FVH, and patients with these deficiencies should be vaccinated against HAV and other liver-tropic viruses.

Possible Role of Extracellular Vesicles in Hepatotoxicity of Acetaminophen

We examined proteomic profiles of rat liver extracellular vesicles (EVs) shed following treatment with a sub-toxic dose (500 mg/kg) of the pain reliever drug, acetaminophen (APAP). EVs representing the entire complement of hepatic cells were isolated after perfusion of the intact liver and analyzed with LC-MS/MS. The investigation was focused on revealing the function and cellular origin of identified EVs proteins shed by different parenchymal and non-parenchymal liver cells and their possible role in an early response of this organ to a toxic environment. Comparison of EV proteomic profiles from control and APAP-treated animals revealed significant differences. Alpha-1-macroglobulin and members of the cytochrome P450 superfamily were highly abundant proteins in EVs shed by the normal liver. In contrast, proteins like aminopeptidase N, metalloreductase STEAP4, different surface antigens like CD14 and CD45, and most members of the annexin family were detected only in EVs that were shed by livers of APAP-treated animals. In EVs from treated livers, there was almost a complete disappearance of members of the cytochrome P450 superfamily and a major decrease in other enzymes involved in the detoxification of xenobiotics. Additionally, there were proteins that predominated in non-parenchymal liver cells and in the extracellular matrix, like fibronectin, receptor-type tyrosine-protein phosphatase C, and endothelial type gp91. These differences indicate that even treatment with a sub-toxic concentration of APAP initiates dramatic perturbation in the function of this vital organ.

Perspective of placenta derived mesenchymal stem cells in acute liver failure

Acute Liver failure (ALF) is a life-threatening disease and is determined by coagulopathy (with INR ≥ 1.5) and hepatic encephalopathy as a result of severe liver injury in patients without preexisting liver disease. Since there are problems with liver transplantation including lack of donors, use of immunosuppressive drugs, and high costs of this process, new therapeutic approaches alongside current treatments are needed. The placenta is a tissue that is normally discarded after childbirth. On the other hand, human placenta is a rich source of mesenchymal stem cells (MSCs), which is easily available, without moral problems, and its derived cells are less affected by age and environmental factors. Therefore, placenta-derived mesenchymal stem cells (PD-MSCs) can be considered as an allogeneic source for liver disease. Considering the studies on MSCs and their effects on various diseases, it can be stated that MSCs are among the most important agents to be used for novel future therapies of liver diseases. In this paper, we will investigate the effects of mesenchymal stem cells through migration and immigration to the site of injury, cell-to-cell contact, immunomodulatory effects, and secretory factors in ALF.

Presentations Related to Acute Paracetamol Intoxication in an Urban Emergency Department in Switzerland

Aim

To investigate the characteristics of Emergency Department (ED) presentations due to acute paracetamol intoxication.

Methods

Retrospective observational study of patients presenting to the ED of Bern University Hospital between May 1, 2012, and October 31, 2018, due to a paracetamol overdose (defined as intake of >4 g/24 h). Cases were identified using the full-text search of the electronic patient database and were grouped into intentional (suicidal/parasuicidal) and unintentional intoxications (e.g., patient unaware of maximal daily dose).

Results

During the study period, 181 cases were included and 143 (79%) of those were intentional. Compared to the patients in the unintentional group, patients in the intentional group were more often female (85% vs 45%, p < 0.001) and younger (median age 23.0 vs 43.5 years, p < 0.001), more frequently suffered from psychiatric comorbidities (93%, (including 49% with borderline personality disorder) vs 24%, p < 0.001), and paracetamol was more often taken as a single dose (80% vs 13%, p < 0.001). Although the median daily ingested dose was lower in the unintentional than in the intentional group (8.2 g vs 12.9 g, p < 0.001), patients in the unintentional group presented later (29% vs 84% within 24 h of ingestion, p < 0.001), included more cases of acute liver failure (nine (24%) vs six (4%), p < 0.001), and were more often hospitalised (24% vs 52% treated as outpatients, p=0.002). There were no significant differences between the groups regarding drug-induced liver injury (seven cases (5%) in the intentional and one (3%) in the unintentional group) or fatalities (one in each group).

Conclusions

The majority of presentations due to paracetamol poisoning were intentional, most commonly in female patients with borderline personality disorder. Patients with unintentional paracetamol intoxication had worse outcomes with respect to acute liver failure and hospitalisation. Future preventive measures should raise awareness of paracetamol toxicity in the general population and encourage particular attention and frequent follow-ups when prescribing paracetamol for vulnerable groups.

Autoimmune Hepatitis-Immunologically Triggered Liver Pathogenesis-Diagnostic and Therapeutic Strategies

Autoimmune hepatitis (AIH) is a severe liver disease that arises in genetically predisposed male and female individuals worldwide. Diagnosis of AIH is made clinically applying diagnostic scores; however, the heterotopic disease phenotype often makes a rapid determination of disease challenging. AIH responds favorably to steroids and pharmacologic immunosuppression, and liver transplantation is only necessary in cases with acute liver failure or end-stage liver cirrhosis. Recurrence or development of de novo AIH after transplantation is possible, and treatment is similar to standard AIH therapy. Current experimental investigations of T cell-mediated autoimmune pathways and analysis of changes within the intestinal microbiome might advance our knowledge on the pathogenesis of AIH and trigger a spark of hope for novel therapeutic strategies.

Acetaminophen is Undetectable in Plasma From More Than Half of Patients Believed to Have Acute Liver Failure Due to Overdose

BACKGROUND & AIMS

Evaluation of patients with acute liver injury (ALI) or acute liver failure (ALF) often includes measurement of plasma levels of acetaminophen, to determine exposure and/or toxicity. However, once liver injury has developed, acetaminophen might be undetectable in plasma. We investigated the association between level of acetaminophen measured and outcomes of patients designated as having ALF or ALI due to acetaminophen toxicity.

METHODS

We performed a retrospective analysis of data from 434 subjects in the Acute Liver Failure Study Group who met criteria for ALF (coagulopathy and hepatic encephalopathy within 26 weeks of the first symptoms, without pre-existing liver disease) or ALI (severe liver injury with coagulopathy but no encephalopathy) due to acetaminophen toxicity from January 1, 2010 through December 31, 2014. We collected data on patient demographics, biochemical features, reported acetaminophen use, N-acetylcysteine therapy, liver transplant, and outcomes. Descriptive statistics were used to assess patient demographics, clinical characteristics, and outcomes whereas differences in continuous variables between patients with vs without acetaminophen detection on admission were analyzed using the Wilcoxon rank-sum test. The primary aim was to determine the proportion of patients with detectable plasma levels of acetaminophen.

RESULTS

Acetaminophen was undetectable in serum samples from 227 patients (52%). There were no significant differences between groups of patients with detectable vs undetectable levels in demographic features, alcohol use, median levels of alanine aspartate, or use of N-acetylcysteine (given to 94.7% of patients with detectable acetaminophen vs 95.9% of those with undetectable acetaminophen; P=.63). We observed a significant difference in median dose taken between patients with detectable (29,500 mg; interquartile range, 15,000 mg-50,007 mg) vs no detectable parent compound (14,950 mg; interquartile range, 3960 mg-25,000) (P=.003). A lower proportion of patients with detectable plasma levels of acetaminophen (72.3%) survived without a liver transplant than of patients with undetectable levels (86.3%) in univariate analysis (P=.0006), although this was not significant in multivariable analysis (P=.12). Although most patients had unintentional overdoses, a higher proportion of patients with suicidal overdoses (43%) had detectable levels of acetaminophen than patients with accidental overdoses (29.3%; P=.01).

CONCLUSION

More than half of patients who present at the hospital with acetaminophen-induced ALI or ALF have undetectable levels of acetaminophen. Clinicians should not exclude acetaminophen toxicity because of undetectable levels or withhold N-acetylcysteine for patients with ALI or ALF when acetaminophen toxicity is suspected.

Abdominal Compartment Syndrome After Liver Transplant in Drug-Induced Acute Liver Failure: A Case Report

The incidence of drug-induced acute liver failure (ALF) has been increasing in recent years. Despite the complex intensive treatment, liver transplant should be performed in progressive cases. A systemic inflammatory response syndrome and the burden of surgical intervention promote abdominal compartment syndrome (ACS); observed preoperatively, they are significant negative prognostic factors. THE CASE: We demonstrate a young woman with liver transplant after ALF and a consecutive ACS. We presumed drug toxicity in the background of the rapidly progressive ALF, based on the preoperative hematologic examination and the histology of the removed liver. An ACS has occurred in the postoperative period that must have been resolved with mesh, and later, anatomic segment 2-3 resection had to be performed to further decrease the pressure. The patient left the hospital after 62 days with good graft function. DISCUSSION: A complex intensive care is mandatory in the case of orthotopic liver transplant for ALF. Outcomes are good after orthotopic liver transplant. An ACS might occur after surgery. In these rare cases a delayed abdominal closure or even a liver resection can be the only solution and sometimes an urgent need to resolve the life-threatening problem.

Early Prognostic Predictive System of AECHB and the Diagnosis of Severe Hepatitis B (Liver Failure)

This chapter describes the evaluations for the progression of chronic liver diseases, recent achievement for screening and early warning-parameters of AECHB, diagnosis criteria and grading standards of HBV ACLF.

Several methods have been used to evaluate the progression of chronic liver diseases, including the Child–Turcotte–Pugh (CTP) score, MELD, MESO index, MELD-Na joint formula, iMELD formula, King’s College Hospital (KCH) score, Sequential Organ Failure Assessment (SOFA) score and the Tongji prognostic predictor model (TPPM) score.

Technologies used for early screening of severe hepatitis B include gene-based diagnostic techniques, such as the polymerase chain reaction, gene sequence analysis, gene chips, and GWAS. Protein-based methods include two-dimensional gel electrophoresis and mass spectrometry; and epigenetic-based methods include assays of DNA methylation and histone modifications. In addition, meta-genomics and systematic biology have been used to analyze microbial sequence and function.

Early-warning parameters for severe hepatitis B mainly include serum concentrations of ALT, AST, total bilirubin, albumin and pre-albumin, and cholinesterase; and measurements of blood ammonia, prothrombin time and prothrombin activity. Several new parameters related to severe hepatitis B have been identified, including gene mutations (e.g. HBV 1896 site mutation and 1762/1764 double mutation), genetic molecular targets (e.g. CXCL10-201 g/A, IL10-592 t/C, ESR1 IVS1-401 t/C, TBX21-1993 t/C, and ICAM1 R241-E469), immune factors (e.g. TNF-α, reactive oxygen species, reactive nitrogen species, sCD163, hfgl2, HLA-DR, NK cells, CTL, Th17 cells, Treg cells, PD-1/PD-L), and metabolic factors (e.g. lecithin, fat amides and bile acids).

The clinical diagnosis of severe hepatitis B is mainly based on clinical manifestations, including jaundice, coagulation disorders, hepatic encephalopathy and ascites, and laboratory tests, including prothrombin time, prothrombin activity, international normalized ratio, AST/ALT ratio, and serum concentrations of albumin, bilirubin, cholinesterase, cholesterol, lactic acid, and alpha-fetoprotein.

At present, there are differences among countries in the standard for diagnosing liver failure. In China, liver failure is referred to as severe hepatitis, whereas, in western counties, liver failure caused by viruses is diagnosed as fulminant hepatitis and refers only to acute liver failure. The main difference is that, in China, the concept of acute fulminant hepatitis has been extended to patients without encephalopathy. In contrast, hepatic encephalopathy II is a necessary condition to diagnose severe hepatitis in the United States, Europe and Japan.

Liver failure can be subdivided into acute and chronic liver failure. Acute liver failure includes acute and sub-acute liver failure, and chronic liver failure includes acute-on-chronic and chronic decompensated liver failure. To date, hepatic encephalopathy has been necessary for the diagnosis of acute, but not chronic, liver failure, which is characterized by decompensated liver.

Classification and Epidemiologic Aspects of Acute Liver Failure

Acute liver failure is a rare condition with high short-term morbidity and mortality. The most widely accepted definition is an abnormality in coagulation with any degree of encephalopathy in a patient without cirrhosis and an illness duration of less than 26 weeks. Multiple classifications systems are currently in use to help categorize the condition. This article reviews the most commonly used systems. The epidemiologic aspects of the disease are also reviewed, including incidence, prevalence, demographics, geographic distribution, and racial and cultural factors and are discussed for the various subtypes of acute liver failure.

Hepatotoxicity associated with statins

Treatment with statins is known all over the world. They are generally considered safe at therapeutic doses. Nevertheless, clinical trials are not enough to assess their scarce adverse effects such as idiosyncratic drug induced liver injury (DILI). Due to some conditions, such as concomitant usage (drug-drug interaction using an identical metabolising enzyme) and genetic polymorphisms, there is an increasing concern about their safety. Hepatotoxicity and rhabdomyolysis have begun to appear in published studies. Most of investigations have focused on both these adverse effects and mechanisms of drug induced toxicity. The present review has attempted to compile almost all of the existing studies on the hepatotoxicity of statins but not rhabdomyolysis. The aim of our study is to provide an overview of the studies on the statin-associated hepatotoxicity and to discuss the published studies. The researchers are of the opinion that the research on this topic is incomplete but extremely necessary.

Liver transplantation for acute liver failure

Before liver transplantation became widely applicable as a treatment option, the mortality rate for acute liver failure was as high as 85%. Today, acute liver failure is a relatively common transplant indication in some settings, but the results of liver transplantation in this context appear to be worse than those for chronic forms of liver disease. In this review, we discuss the indications and contraindications for urgent liver transplantation. In particular, we consider the roles of auxiliary, ABO-incompatible, and urgent living donor liver transplantation and address the management of a «status 1» patient with total hepatectomy and portocaval shunt for toxic liver syndrome.

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

Objective:

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

Materials and Methods:

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

Results:

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

Conclusion:

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

Validity of diagnostic codes and laboratory tests of liver dysfunction to identify acute liver failure events

PURPOSE

Identification of acute liver failure (ALF) is important for post-marketing surveillance of medications, but the validity of using ICD-9 diagnoses and laboratory data to identify these events within electronic health records is unknown. We examined positive predictive values (PPVs) of hospital ICD-9 diagnoses and laboratory tests of liver dysfunction for identifying ALF within a large, community-based integrated care organization.

METHODS

We identified Kaiser Permanente Northern California health plan members (2004-2010) with a hospital diagnosis suggesting ALF (ICD-9 570, 572.2, 572.4, 572.8, 573.3, 573.8, or V42.7) plus an inpatient international normalized ratio ≥1.5 (off warfarin) and total bilirubin ≥5.0 mg/dL. Hospital records were reviewed by hepatologists to adjudicate ALF events. PPVs for confirmed outcomes were determined for individual ICD-9 diagnoses, diagnoses plus prescriptions for hepatic encephalopathy treatment, and combinations of diagnoses in the setting of coagulopathy and hyperbilirubinemia.

RESULTS

Among 669 members with no pre-existing liver disease, chart review confirmed ALF in 62 (9%). Despite the presence of co-existing coagulopathy and hyperbilirubinemia, individual ICD-9 diagnoses had low PPVs (range, 5-15%); requiring prescriptions for encephalopathy treatment did not increase PPVs of these diagnoses (range, 2-23%). Hospital diagnoses of other liver disorders (ICD-9 573.8) plus hepatic coma (ICD-9 572.2) had high PPV (67%; 95%CI, 9-99%) but only identified two (3%) ALF events.

CONCLUSIONS

Algorithms comprising relevant hospital diagnoses, laboratory evidence of liver dysfunction, and prescriptions for hepatic encephalopathy treatment had low PPVs for confirmed ALF events. Studies of ALF will need to rely on medical records to confirm this outcome.

Model for end-stage liver disease score as a predictor of short-term outcome in patients with drug-induced liver injury

OBJECTIVES

The purposes of this study were to investigate the clinical presentation, cause and outcome of drug-induced liver injury (DILI) and to evaluate the predictive value of the model for end-stage liver disease (MELD) score in DILI.

METHODS

Patients diagnosed with DILI between January 1, 2010 and December 31, 2012 in the Emergency Department at Asan Medical Center in Seoul, Korea were analyzed retrospectively. The primary end point was poor outcome, defined as liver transplantation or death within 30 days of the initial hospital visit.

RESULTS

Of 213 patients, 13.1% had a 30-day poor outcome. Folk remedies were the most common cause of DILI in 147 patients (69%). Univariate logistic regression analysis showed that multiple drugs (odds ratio [OR] 2.30, 95% confidence interval [CI]: 1.03-5.15), concurrent alcohol consumption (OR 3.69, 95% CI: 1.03-13.18), white blood cell (WBC) count (OR 1.17, 95% CI: 1.07-1.28), hemoglobin (Hb) (OR 0.60, 95% CI: 0.49-0.74), platelet count (OR 0.993, 95% CI: 0.987-0.998), total bilirubin (OR 1.09, 95% CI: 1.06-1.13) and MELD (OR 1.23, 95% CI: 1.15-1.32) were significantly associated with 30-day poor outcomes. Multivariate analysis showed that the MELD (OR 1.21, 95% CI: 1.12-1.30) and Hb (OR 0.77, 95% CI: 0.61-0.98) were independent predictors of poor outcome. For 30-day mortality, the c-statistics for MELD alone and for combination of MELD and Hb were 0.93 (95% CI: 0.89-0.97) and 0.94 (95% CI: 0.90-0.97), respectively.

CONCLUSION

The outcome of patients with DILI was poor. MELD score and Hb were reliable predictors of short-term outcome in patients with DILI.

Prognostic indicators for acute liver failure development and mortality in patients with hepatitis A: consecutive case analysis

PURPOSE

Due to the seroepidemiological shift in hepatitis A (HA), its severity, mortality, and complications have increased in recent years. Thus, the aim of this study was to identify predictive factors associated with poor prognosis among patients with HA.

MATERIALS AND METHODS

A total of 304 patients with HA admitted to our institution between July 2009 and June 2011 were enrolled consecutively. Patients with complications defined as acute liver failure (ALF) were evaluated, and mortality was defined as death or liver transplantation.

RESULTS

The mean age of patients (204 males, 100 females) was 32 years. Eighteen (5.9%) patients had progressed to ALF. Of the patients with ALF, 10 patients (3.3%) showed spontaneous survival while 8 (2.6%) died or underwent liver transplantation. Multivariate regression analysis showed that Model for End-Stage Liver Disease (MELD) and systemic inflammatory response syndrome (SIRS) scores were significant predictive factors of ALF. Based on receiver operating characteristics (ROC) analysis, a MELD≥23.5 was significantly more predictive than a SIRS score≥3 (area under the ROC: 0.940 vs. 0.742, respectively). In addition, of patients with a MELD score≥23.5, King's College Hospital criteria (KCC) and SIRS scores were predictive factors associated with death/transplantation in multivariate analysis.

CONCLUSION

MELD and SIRS scores≥23.5 and ≥3, respectively, appeared to be related to ALF development. In addition, KCC and SIRS scores≥3 were valuable in predicting mortality of patients with a MELD≥23.5.

APACHE III score is superior to King's College Hospital criteria, MELD score and APACHE II score to predict outcomes after liver transplantation for acute liver failure

OBJECTIVES

The Model for End-Stage Liver Disease score and King's College Hospital (KCH) criteria are accepted prognostic models acute liver failure (ALF), while the use of (APACHE) scores predict to outcomes of emergency liver transplantation is rare.

MATERIALS AND METHODS

The present study included 87 patients with ALF who underwent liver transplantation. We calculated (KCH) criteria, as well as MELD, APACHE II, and APACHE III scores at the listing date for comparison with 3-month outcomes.

RESULTS

According to the Youden-Index, the best cut-off value for the APACHE II score was 8.5 with 100% sensitivity, 49% specificity, 24% positive predictive value (PPV), and 100% negative predictive value (NPV). Patients with <8.5 points had a significantly higher survival rate (P < .05). The proposed APACHE III cut-off was 80. The APACHE III score demonstrated the highest specificity and PPV (90% specificity, 50% PPV). The NPV was 92%. With a 90-point threshold the specificity increased to 98% with 75% PPV and 89% NPV. Only 1 of 4 patients with a score >90 survived transplantation (P = .001). MELD score and KCH criteria were not significant (P > .05). According to the Hosmer-Lemeshow test, only the APACHE III score adequately describe the data.

CONCLUSIONS

The APACHE III score was superior to KCH criteria, MELD score, and APACHE II score to predict outcomes after transplantation for ALF. It is a valuable parameter for pretransplantation patient selection.

Clinical characteristics and outcomes of acute hepatitis a in Korea: a nationwide multicenter study

The aim of this study was to investigate the clinical characteristics of acute hepatitis A during a recent outbreak in Korea. Data of patients diagnosed with acute hepatitis A from 2007 to 2009 were collected from 21 tertiary hospitals retrospectively. Their demographic, clinical, and serological characteristics and their clinical outcomes were analyzed. A total of 4,218 patients (mean age 33.3 yr) were included. The median duration of admission was 9 days. The mean of the highest ALT level was 2,963 IU/L, total bilirubin was 7.3 mg/dL, prothrombin time INR was 1.3. HBsAg was positive in 3.7%, and anti-HCV positive in 0.7%. Renal insufficiency occurred in 2.7%, hepatic failure in 0.9%, relapsing hepatitis in 0.7%, and cholestatic hepatitis in 1.9% of the patients. Nineteen patients (0.45%) died or were transplanted. Complications of renal failure or prolonged cholestasis were more frequent in patients older than 30 yr. In conclusion, most patients with acute hepatitis A recover uneventfully, however, complication rates are higher in patients older than 30 yr than younger patients. Preventive strategies including universal vaccination in infants and active immunization of hepatitis A to adult population should be considered for prevention of community-wide outbreaks of hepatitis A in Korea.

Mechanisms of Acute Liver Failure

Acute liver failure (ALF) is characterized by the sudden onset of liver failure in a patient without evidence of chronic liver disease. This definition is important, as it differentiates patients with ALF from patients who suffer from liver failure owing to end-stage chronic liver disease [1].

Validity of diagnostic codes to identify cases of severe acute liver injury in the US Food and Drug Administration's Mini-Sentinel Distributed Database

PURPOSE

The validity of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes to identify diagnoses of severe acute liver injury (SALI) is not well known. We examined the positive predictive values (PPVs) of hospital ICD-9-CM diagnoses in identifying SALI among health plan members in the Mini-Sentinel Distributed Database (MSDD) for patients without liver/biliary disease and for those with chronic liver disease (CLD).

METHODS

We selected random samples of members (149 without liver/biliary disease; 75 with CLD) with a principal hospital diagnosis suggestive of SALI (ICD-9-CM 570, 572.2, 572.4, 572.8, 573.3, 573.8, or V42.7) in the MSDD (2009-2010). Medical records were reviewed by hepatologists to confirm SALI events. PPVs of codes and code combinations for confirmed SALI were determined by CLD status.

RESULTS

Among 105 members with available records and no liver/biliary disease, SALI was confirmed in 26 (PPV, 24.7%; 95%CI, 16.9-34.1%). Combined hospital diagnoses of acute hepatic necrosis (570) and liver disease sequelae (572.8) had high PPV (100%; 95%CI, 59.0-100%) and identified 7/26 (26.9%) events. Among 46 CLD members with available records, SALI was confirmed in 19 (PPV, 41.3%; 95%CI, 27.0-56.8%). Acute hepatic necrosis (570) or hepatorenal syndrome (572.4) plus any other SALI code had a PPV of 83.3% (95%CI, 51.6-97.9%) and identified 10/19 (52.6%) events.

CONCLUSIONS

Most individual hospital ICD-9-CM diagnoses had low PPV for confirmed SALI events. Select code combinations had high PPV but did not capture all events.

ATT- A Double Edged Sword?

Antitubercular therapy (ATT) induced hepatotoxicity, although well known to clinicians, is often over looked and underrated. Given the low threshold of starting ATT, especially empirically, the adverse manifestations can take a considerable toll. A variety of associated risk factors compound the morbidity. We throw light on one such a case where ATT was detrimental to the patient and review the literature and possible preventive strategies.

Safety of saxagliptin: rationale for and design of a series of postmarketing observational studies

PURPOSE

To describe the design and rationale of a series of postmarketing studies to examine the safety of saxagliptin, an oral dipeptidyl peptidase-4 inhibitor for the treatment of type 2 diabetes mellitus, in real-world settings.

METHODS

We are conducting a series of retrospective cohort studies using two UK (General Practice Research Database, and The Health Improvement Network) and two US (Medicare, HealthCore Integrated Research Database(SM) ) data sources. The primary outcomes of interest will include (i) hospitalization with acute liver failure, (ii) hospitalization for acute kidney injury, (iii) hospitalization for severe hypersensitivity reactions, (iv) hospitalization for severe infections, (v) hospitalization with infections associated with T-lymphocyte dysfunction (i.e., herpes zoster, tuberculosis, or nontuberculous mycobacteria), and (vi) major cardiovascular events. Diagnosis codes for the outcomes of interest will be validated by medical record review within each data source. Projected use and estimated incidence rates of outcomes of interest suggest there will be at least 80% statistical power to detect a minimum hazard ratio of 1.5 for major cardiovascular events, 2.0 for acute kidney injury and severe infections, 2.4 for acute liver failure, and 4.0 for severe hypersensitivity reactions.

RESULTS

Forthcoming.

CONCLUSIONS

This postmarketing safety assessment will provide important information regarding the safety of saxagliptin and could potentially identify important dipeptidyl peptidase-4 inhibitor class effects. The methods described may be useful to others planning similar evaluations.

Expression and role of Urotensin Ⅱ in lipopolysaccharide/D-galactosamine-induced acute liver failure in mice

AIM: To investigate the expression and role of Urotensin Ⅱ (UⅡ) in lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced acute liver failure (ALF) in mice.

METHODS: Male Balb/c mice were randomly and equally divided into four groups: normal control group (group A), pre-treatment control group (group B), ALF model group (group C), and pre-treatment model group (group D). ALF were induced in mice by intraperitoneal injection of LPS (50 μg/kg body weight)/D-GalN (800 mg/kg body weight). The pre-treatment mice were intravenously injected with Urantide (0.6 mg/kg body weight) 30 min before model induction. Serum and liver tissues were sampled 12 h after LPS/D-GalN injection. Mortality was calculated 24 h after attack. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected using the Reitman-Frankel method. Histopathological changes were observed by hematoxylin and eosin (HE) staining. Serum UⅡ levels were assessed by ELISA, and the expression of UⅡ and UT was detected by RT-PCR and immunohistochemistry.

RESULTS: A mortality of 66.7% was observed in group C, while all mice of groups A, B and D survived. Serum ALT and AST levels had a dramatic increase in groups C and D, but were significantly lower in group D than in group C (2 271.09 U/L ± 102.24 U/L vs 1 160.67 U/L ± 258.32 U/L, 1 569.42 U/L ± 204.04 U/L vs 1 030.31 U/L ± 108.09 U/L, both P < 0.01). Widespread destruction of liver architecture, hemorrhagic necrosis, and neutrophil infiltration were noted in group C, whereas liver architecture was completely preserved, and focal necrosis and fewer neutrophil infiltrates were observed in group D. After LPS/D-GalN challenge, serum UⅡ levels increased sharply in groups C and D, but were lower in group D than in group C (3.73 μg/L ± 0.52 μg/L vs 1.90 μg/L ± 0.27 μg/L, both P < 0.01). Overexpression of liver UⅡ and UT mRNAs and proteins was induced by the injection of LPS/D-GalN in groups C and D. Compared to group C, group D had lower levels of UⅡ and UT in the liver.

CONCLUSION: UⅡ expression and secretion can be induced by LPS/D-GalN challenge in the liver tissue of ALF mice via a positive feedback mechanism associated with promoting the expression of its receptor UT. UⅡ/UT receptor may be a vital mediator of LPS/D-GalN-induced ALF.

Hepatoprotective effect and mechanistic insights of deoxyelephantopin, a phyto-sesquiterpene lactone, against fulminant hepatitis

Deoxyelephantopin (DET) is an abundant sesquiterpene lactone isolated from an anecdotally hepatoprotective phytomedicine, Elephantopus scaber. Our objective in this study was to provide scientific evidence for the in vivo efficacy and the underlying mechanisms of action of DET in lipopolysaccharide/d-galactosamine (LPS/D-GalN)-induced fulminant hepatitis. We investigated both the protective effect of pretreatment with DET (10 mg/kg body weight, Pre-DET10) prior to administration of LPS/D-GalN and the therapeutic effect of treatment with 10 mg/kg DET (Post-DET10) or the hepatoprotective drug silymarin (Post-SM10) following the administration of LPS/D-GalN. Our data showed that Pre-DET10 prevented LPS/D-GalN-induced infiltration of F4/80 monocytes/macrophages and an increase of nitrotyrosine and cyclooxygenase-2 protein in liver tissues. Further, Post-DET10 and Psot-SM10 treatments protected against liver cell apoptosis. All three treatments suppressed serum aminotransferase activities, tumor necrosis factor-alpha and interleukin-6 levels, and serum and hepatic matrix metalloproteinase-9 activity. The Pre-DET10 or Post-DET10 and Post-SM10 treatments in combination with inhibition of heme oxygenase-1 expression ultimately decreased protection of mice from LPS/D-GalN-induced mortality, with decreased survival from 75% and 62.5% to 50%, respectively. Results obtained from serial liver scintigraphy with (99m)Tc-diisopropyl iminodiacetic acid (DISIDA) on single-photon emission computed tomography analysis showed that both liver uptake and excretion times of DISIDA were significantly delayed in LPS/D-GalN-treated animals and were effectively recovered by DET and silymarin treatment. This report demonstrates that DET functions in the modulating multiple molecular targets or signaling pathways that counteract inflammation during the progression of fulminant hepatitis and may serve as a novel lead compound for future development of anti-inflammatory or hepatoprotective agents.

Safety evaluation of stem cells used for clinical cell therapy in chronic liver diseases; with emphasize on biochemical markers

There are several issues to be considered to reduce the risk of rejection and minimize side effects associated with liver cell transplantation in chronic liver diseases. The source and the condition of stem cell proliferation and differentiation ex vivo and the transplantation protocols are important safety considerations for cell based therapy. The biochemical and molecular markers are important tools for safety evaluation of different processes of cell expansion and transplantation. Studies show that hepatocytes differentiated from adult and embryonic stem cells exhibit biochemical and metabolic properties resembling mature hepatocytes. Therefore these assays can help to assess the biological and metabolic performance of hepatocytes and progenitor stem cells. The assays also help in testing the contribution of transplanted hepatocytes in improving the repair and function of damaged liver in the recipient. Here we review the biochemical and metabolic markers, which are implicated in evaluation of safety issues of stem cells used for therapeutic purposes in chronic liver diseases and regeneration of damaged liver. We also highlight application of biochemical tests for assessment of liver cell transplantation.

Prevalence and clinical significance of Cryptosporidium infection in patients with hepatitis B virus-associated acute-on-chronic liver failure

BACKGROUND

Patients with acute-on-chronic liver failure (ACLF) are often highly susceptible to microbial infection due to a depressed immune system. This study was carried out to investigate the prevalence and clinical significance of Cryptosporidium infection in patients with hepatitis B virus (HBV)-associated ACLF in Hunan Province, China.

METHODS

Fecal samples from 218 patients with HBV-associated ACLF, 122 patients with chronic hepatitis B (CHB), and 140 children with diarrhea were collected; Cryptosporidium infection was detected by auramine-phenol staining, modified acid-fast staining, and the polymerase chain reaction. The clinical characteristics of this parasitic infection in Cryptosporidium-positive ACLF patients were further evaluated.

RESULTS

The prevalence of Cryptosporidium infection in the HBV-associated ACLF patients was 6.0% (13/218), which was markedly higher than that found in CHB patients (0.8%, 1/122) and in children with diarrhea (1.4%, 2/140). Although watery diarrhea was not seen in the 13 Cryptosporidium-positive ACLF patients, eight (61.5%) of them had diarrhea. Moreover, our investigation showed that Cryptosporidium infection was not associated with the severity of the disease in ACLF patients.

CONCLUSIONS

The prevalence of Cryptosporidium infection is high among patients with HBV-associated ACLF and might be a significant cause of diarrhea in this population.

Bioactive phytochemicals of leaf essential oils of Cinnamomum osmophloeum prevent lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced acute hepatitis in mice

The purpose of this study was to investigate the bioactive phytochemicals of leaf essential oils of Cinnamomum osmophloeum on lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced acute hepatitis. The results revealed that post-treatment with 100 μmol/kg trans-cinnamaldehyde, (-)-aromadendrene, T-cadinol, or α-cadinol significantly decreased the aspartate aminotransferase (AST), alanine aminotransferase (ALT), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) levels in serum. Moreover, both T-cadinol and α-cadinol treatments decreased the expressions of cleaved caspase-3 and cleaved poly-ADP ribose polymerase (PARP) in the liver tissues when compared with the LPS/D-GalN group. Liver histopathology also showed that silymarin, trans-cinnamaldehyde, (-)-aromadendrene, T-cadinol, or α-cadinol significantly reduced the incidence of liver lesions induced by LPS/D-GalN. These results suggest that the above phytochemicals exhibit potent hepatoprotection against LPS/D-GalN-induced liver damage in mice, and their hepatoprotective effects may be due to the modulation of anti-inflammatory activities.

Use of hepatocyte and stem cells for treatment of post-resectional liver failure: are we there yet?

Post-operative liver failure following extensive resections for liver tumours is a rare but significant complication. The only effective treatment is liver transplantation (LT); however, there is a debate about its use given the high mortality compared with the outcomes of LT for chronic liver diseases. Cell therapy has emerged as a possible alternative to LT especially as endogenous hepatocyte proliferation is likely inhibited in the setting of prior chemo/radiotherapy. Both hepatocyte and stem cell transplantations have shown promising results in the experimental setting; however, there are few reports on their clinical application. This review identifies the potential stem cell sources in the body, and highlights the triggering factors that lead to their mobilization and integration in liver regeneration following major liver resections.

Drug-induced autoimmune-like hepatitis

The clinical phenotype of classical autoimmune hepatitis can be mimicked by idiosyncratic drug-induced liver injury, and differentiation can be difficult. The goals of this review are to enumerate the major agents of drug-induced autoimmune-like hepatitis, describe the clinical findings and risk factors associated with it, detail the clinical tools by which to assess causality, discuss putative pathogenic mechanisms, and describe treatment and outcome. The frequency of drug-induced autoimmune-like hepatitis among patients with classical features of autoimmune hepatitis is 9%. Minocycline and nitrofurantoin are implicated in 90% of cases. Female predominance, acute onset, and absence of cirrhosis at presentation are important clinical manifestations. Genetic factors affecting phase I and phase II transformations of the drug, polymorphisms that protect against cellular oxidative stress, and human leukocyte antigens that modulate the immune response may be important pathogenic components. Clinical judgment is the mainstay of diagnosis as structured diagnostic methods for drug-induced liver injury are imperfect. The covalent binding of a reactive drug metabolite to a hepatocyte surface protein (commonly a phase I or phase II enzyme), formation of a neoantigen, activation of CD8 T lymphocytes with nonselective antigen receptors, and deficient immune regulatory mechanisms are the main bases for a transient loss of self-tolerance. Discontinuation of the offending drug is the essential treatment. Spontaneous improvement usually ensues within 1 month. Corticosteroid therapy is warranted for symptomatic severe disease, and it is almost invariably effective. Relapse after corticosteroid withdrawal probably does not occur, and its absence distinguishes drug-induced disease from classical autoimmune hepatitis.

Drug-induced acute liver failure and gastrointestinal complications

The objective of this article is to describe adverse drug events related to the liver and gastrointestinal tract in critically ill patients. PubMed and other resources were used to identify information related to drug-induced acute liver failure, gastrointestinal hypomotility, constipation, diarrhea, gastrointestinal bleeding, and pancreatitis in critically ill patients. This information was reviewed, and data regarding pathophysiology, common drug causes, and guidelines for prevention and management were collected and summarized. In cases in which data in critically ill patients were unavailable, data were extrapolated from other patient populations. Drug-induced acute liver failure can be caused by many drugs routinely used in the intensive care unit and may be associated with significant morbidity and mortality. Drug-related hypomotility and constipation and drug-related diarrhea are reported with many drugs, and these are common adverse drug events in critically ill patients that can substantially complicate the care of these patients. Drug-induced gastrointestinal bleeding and drug-induced pancreatitis occur less frequently, can range in disease severity, and can be associated with morbidity and mortality. Many drugs used in critically ill patients are associated with adverse drug events related to the liver and gastrointestinal tract. Critical care clinicians should be aware of common drug causes of drug-induced acute liver failure, gastrointestinal hypomotility, constipation, diarrhea, gastrointestinal bleeding, and pancreatitis, and should be familiar with the prevention and management of these diverse conditions.

Fulminant hepatic failure: when to transplant

Fulminant hepatic failure is a life-threatening condition that can lead to rapid deterioration and death if timely treatment is not instituted. Many patients recover with supportive care. Patients with deteriorating signs and laboratory parameters require prompt assessment and listing for liver transplantation. Outcome following transplantation is a function of severity of illness before transplantation, timeliness of liver transplantation and graft quality and function. With appropriate immunosuppression and close follow-up most patients can lead near normal lives following liver transplantation.

Natural course of fulminant hepatic failure: the scenario in Bangladesh and the differences from the west

BACKGROUND/AIM

Fulminant hepatic failure (FHF) is a devastating complication of acute viral hepatitis, leading to death in most cases. The etiology and predictors of outcome differ according to the geographical region. This study was conducted with the aim of evaluating the etiology, complications, and outcome of FHF in Bangladesh.

PATIENTS AND METHODS

In this prospective study, we included 67 consecutive cases of FHF presenting to the Department of Hepatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, between November 2003 and May 2008. Thirty-nine of the patients were male and 28 were female. Data was analyzed using SPSS, version 13.0.

RESULTS

The mean age of the subjects was 31.9 +/- 11 .7 years. Hepatitis E virus (HEV) was the commonest etiological factor for FHF (50 cases, 74.6%); of the 50 cases with HEV infection, 43 (64.2%) were not coinfected with any other virus, four cases were Hepatitis B virus (HBV) carriers, and three had coinfection with hepatitis A virus (HAV). HBV was the cause of FHF in nine (13.4%) patients. HCV, paracetamol, and alcohol were not responsible for any of the cases. Most of the patients (57 patients, 85%) developed FHF within 2 weeks of the onset of jaundice. Of the 67 patients, 49 (73.1%) died. Cerebral edema was the single most common cause of death (48 patients, 71.6%). Other complications were renal failure (23 patients, 34.3%), sepsis (15 patients, 22.4%), electrolyte imbalance (12 patients 17.9%), and bleeding tendency (7 patients, 10.4%). Occurrence of cerebral edema, longer prothrombin time, higher grade of encephalopathy, and longer jaundice-to-encephalopathy interval had significant negative influence on outcome.

CONCLUSIONS

The etiology of FHF in Bangladesh is different from that in the West. Prolongation of prothrombin time and occurrence of cerebral edema are predictors of the worst prognosis.

[Basic mechanisms of hepatocellular injury. Role of inflammatory lipid mediators]

The presence of a lesion in the cellular parenchyma is common to a large number of chronic liver diseases, such as viral hepatitides, alcoholic hepatitis, chronic cholestasis and steatohepatitis. Although the pathogenesis may vary according to the etiological agent, a series of mechanisms is common to all. Notable among these mechanisms are Kupffer cell activation and inflammatory cell recruitment, free oxygen radical formation and the development of oxidative stress, cytokine production, mainly TNFa and TGFb, and inflammatory mediator release due to arachidonic acid oxidation through the COX-2 and 5-LO pathways.

Transgenic expression of cyclooxygenase-2 in hepatocytes accelerates endotoxin-induced acute liver failure

Bacterial LPS (endotoxin) is implicated in the pathogenesis of acute liver failure and several chronic inflammatory liver diseases. To evaluate the effect of hepatocyte cyclooxygenase (COX)-2 in LPS-induced liver injury, we generated transgenic mice with targeted expression of COX-2 in the liver by using the albumin promoter-enhancer driven vector and the animals produced were subjected to a standard experimental protocol of LPS-induced acute fulminant hepatic failure (i.p. injection of low dose of LPS in combination with d-galactosamine (d-GalN)). The COX-2 transgenic mice exhibited earlier mortality, higher serum aspartate aminotransferase and alanine aminotransferase levels and more prominent liver tissue damage (parenchymal hemorrhage, neutrophilic inflammation, hepatocyte apoptosis, and necrosis) than wild-type mice. Western blot analysis of the liver tissues showed that LPS/d-GalN treatment for 4 h induced much higher cleavage of poly(ADP-ribose) polymerase, caspase-3, and caspase-9 in COX-2 transgenic mice than in wild-type mice. Increased hepatic expression of JNK-2 in COX-2 transgenic mice suggest that up-regulation of JNK-2 may represent a potential mechanism for COX-2-mediated exacerbation of liver injury. Blocking the prostaglandin receptor, EP(1), prevented LPS/d-GalN-induced liver injury and hepatocyte apoptosis in COX-2 transgenic mice. Accordingly, the mice with genetic ablation of EP(1) showed less LPS/d-GalN-induced liver damage and less hepatocyte apoptosis with prolonged survival when compared with the wild-type mice. These findings demonstrate that COX-2 and its downstream prostaglandin receptor EP(1) signaling pathway accelerates LPS-induced liver injury. Therefore, blocking COX-2-EP(1) pathway may represent a potential approach for amelioration of LPS-induced liver injury.

Therapeutic hypothermia for acute liver failure: toward a randomized, controlled trial in patients with advanced hepatic encephalopathy

Acute liver failure (ALF), the abrupt loss of liver function in a patient without previous liver disease, remains a highly mortal condition. Patients with ALF often succumb to their liver injury after the development of cerebral edema, resulting in intracranial hypertension and brain herniation. While the management of cerebral edema in ALF always includes the administration of osmotically active agents, osmotherapy often reduces intracranial pressure (ICP) insufficiently, such that herniation may be delayed but not prevented. Therapeutic hypothermia, the intentional reduction of body core temperature, has been increasingly used to treat cerebral edema in patients with traumatic and hypoxic brain injury. Data in animal models of ALF also suggest that hypothermia is effective in the prevention and treatment of cerebral edema, and case reports in humans have suggested that hypothermia is an effective bridge to orthotopic liver transplantation. A randomized, controlled trial comparing the management of ALF patients under normothermic and hypothermic conditions is a logical extension of these preliminary observations. Herein, we consider the many difficulties which will be encountered in the design of such a trial in patients with ALF at high risk of developing cerebral edema.

Bone marrow-derived immune cells mediate sensitization to liver injury in a myeloid differentiation factor 88-dependent fashion

Toll-like receptors (TLRs) expressed on both immune cells and hepatocytes recognize microbial danger signals and regulate immune responses. Previous studies showed that TLR9 and TLR2 mediate Propionibacterium acnes-induced sensitization to lipopolysaccharide-triggered acute liver injury in mice. Ligand-specific activation of TLR2 and TLR9 are dependent on the common TLR adaptor, myeloid differentiation factor 88 (MyD88). Here, we dissected the role of MyD88 in parenchymal and bone marrow (BM)-derived cells in liver sensitization. Using chimeric mice with green fluorescent protein-expressing BM cells, we identified that P. acnes-induced liver inflammatory foci are of BM origin. Chimeras with MyD88-deficient BM showed no inflammatory foci after P. acnes or TLR2+TLR9 challenge, suggesting that recruitment of inflammatory cells to the liver required MyD88 expression in BM-derived cells. Further, selective MyD88 deficiency in parenchymal cells in mice with wild-type BM failed to prevent inflammatory cell infiltration. These results demonstrate that MyD88 in immune cells rather than in liver parenchymal cells plays an important role in inflammatory cell recruitment and liver injury.

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

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

Na+/H+ exchanger inhibitor, FR183998, has protective effect in lethal acute liver failure and prevents iNOS induction in rats

BACKGROUND/AIMS

Selective inhibition of Na(+)/H(+) exchanger (NHE) improves organ dysfunctions including heart ischemia-reperfusion injury. In vivo and in vitro studies were designed to investigate whether NHE inhibitor has a protective effect in lethal acute liver failure, and if so, what are the mechanisms involved.

METHODS

NHE inhibitor (FR183998) was administered to rats treated with d-galactosamine/lipopolysaccharide (GalN/LPS), or incubated with cultured hepatocytes stimulated by pro-inflammatory cytokine, interleukin (IL)-1beta.

RESULTS

FR183998 reduced the increases of pro-inflammatory cytokines such as TNF-alpha, interferon-gamma and CINC-1, but enhanced the anti-inflammatory cytokine, IL-10, leading to the prevention of liver injury and increased survival rate in GalN/LPS-treated animals. FR183998 prevented the activation of transcription factor NF-kappaB induced by GalN/LPS. In vivo and in vitro experiments revealed that FR183998 reduced inducible nitric oxide synthase (iNOS) induction and NO production. Further FR183998 decreased levels of iNOS antisense-transcript in GalN/LPS-treated liver and IL-1beta-treated hepatocytes.

CONCLUSIONS

FR183998 may reduce a variety of inflammatory mediators such as cytokines and NO in part through the inhibition of NF-kappaB activation, resulting in the prevention of fulminant liver failure, and may inhibit iNOS gene expression at steps of iNOS promoter transactivation and its mRNA stabilization through NF-kappaB and iNOS antisense-transcript, respectively.

Acute and chronic liver insufficiency

The term “liver insufficiency” denotes a break down in the functions of the liver. The syndrome of functional liver failure covers a wide spectrum of clinical, biochemical and neurophysiological changes. In principle, liver insufficiency can occur without previous liver damage as well as with already existing liver disease. It is characterized by a deterioration in the synthesizing, regulatory and detoxifying function of the liver. This final stage of liver disease terminates in hepatic coma.

Protective effect of neutrophil elastase inhibitor (FR136706) in lethal acute liver failure induced by D-galactosamine and lipopolysaccharide in rats

BACKGROUND/AIMS

It has been reported that liver dysfunction with ischemia-reperfusion is improved through selective inhibition of neutrophil elastase (NE) by NE inhibitor. This study was designed to investigate whether NE inhibitor has protective effect in lethal acute liver failure.

MATERIALS AND METHODS

Rats were treated with D-galactosamine plus lipopolysaccharide (GalN/LPS) to induce acute liver failure. NE inhibitor (FR136706) was administered intravenously before GalN/LPS injection.

RESULTS

NE inhibitor increased the survival rate to approximately 80% compared with less than 10% in GalN/LPS-treated rats. NE inhibitor prevented GalN/LPS-induced increase of enzymes and total bilirubin in serum, which are related to liver injury. Histopathological analysis revealed that NE inhibitor decreased the incidence of hepatic apoptosis and neutrophil infiltration in the liver. NE inhibitor inhibited the increased concentration of proinflammatory cytokines (tumor necrosis factor-alpha, interleukin-6 and interferon-gamma), and chemokines (CINC-1 and MIP-2) in serum or liver caused by GalN/LPS, and enhanced anti-inflammatory cytokine, interleukin-10 concentration. NE inhibitor prevented the activation of the transcription factor, nuclear factor-kappa B, induced by GalN/LPS. NE inhibitor also reduced the induction of inducible nitric oxide synthase mRNA and its protein in GalN/LPS-treated liver, and resulted in a decrease in nitric oxide production.

CONCLUSIONS

These results indicate that NE inhibitor, FR136706, inhibits the induction of a variety of inflammatory mediators such as cytokines, chemokines, and nitric oxide, in part through the inhibition of nuclear factor-kappa B activation, resulting in the prevention of fulminant liver failure.

Acute liver failure in Spain: analysis of 267 cases

The cause of acute liver failure (ALF) is a major determinant of its outcome. Acetaminophen (paracetamol) overdose is a leading cause of ALF in some developed countries, whereas in others, such as Spain, it is extremely rare. To analyze the etiology, characteristics, and outcome of ALF in Spain, we performed a retrospective analysis of 267 patients whom we observed from 1992 to 2000. Seventeen tertiary-care hospitals with active liver transplantation (LT) programs contributed data. Causes of ALF were viral hepatitis in 98 (37%; hepatitis B virus in 75 patients), unknown in 86 (32%), drug or toxic reactions in 52 (19.5%; acetaminophen overdose in 6), and miscellaneous in 31 (11.6%). Overall survival was 58%. LT was performed in 150 patients, with a survival of 69%. Despite fulfilling criteria, 51 patients were not transplanted because of contraindications; their survival was only 7.8%. Forty-seven (85.5%) of 55 patients without transplant criteria survived. Hepatitis B virus is the most common cause of ALF in Spain, although the origin of 30% of cases remains undetermined. Acetaminophen overdose represents a very rare cause of ALF. LT was performed in >50% of cases. Patients without transplant criteria had a very good prognosis; those who fulfilled these criteria but who had contraindications for transplantation had a high mortality rate.

Acute liver failure in Sweden: etiology and outcome

OBJECTIVE

To determine the causes and outcome of all patients with acute liver failure (ALF) in Sweden 1994-2003 and study the diagnostic accuracy of King's College Hospital (KCH) criteria and the model for end-stage liver disease (MELD) score with transplant-free deaths as a positive outcome.

RESEARCH DESIGN AND METHODS

Adult patients in Sweden with international normalized ratio (INR) of >or=1.5 due to severe liver injury with and without encephalopathy at admission between 1994-2003 were included.

RESULTS

A total of 279 patients were identified. The most common cause of ALF were acetaminophen toxicity in 42% and other drugs in 15%. In 31 cases (11%) no definite etiology could be established. The KCH criteria had a positive-predictive value (PPV) of 67%, negative-predictive value (NPV) of 84% in the acetaminophen group. Positive-predictive value and negative-predictive value of KCH criteria in the nonacetaminophen group were 54% and 63% respectively. MELD score>30 had a positive-predictive value of 21%, negative-predictive value of 94% in the acetaminophen group. The corresponding figures for the nonacetaminophen group were 64% and 76% respectively.

CONCLUSIONS

Acetaminophen toxicity was the most common cause in unselected patients with ALF in Sweden. KCH criteria had a high NPV in the acetaminophen group, and in combination with MELD score<30 predicts a good prognosis in acetaminophen patients without transplantation.