Prognostic implications of lactate, bilirubin, and etiology in German patients with acute liver failure

Association between lactate-to-albumin ratio and mortality in hepatic failure: a retrospective cohort study

BACKGROUND

Liver failure has a high mortality rate, and currently, there is no convenient risk predictor. The lactate-to-albumin ratio (LAR) has emerged as a promising predictor in various critical illnesses. However, its potential role in predicting all-cause mortality in patients with liver failure remains unexplored. Therefore, this study aims to investigate the correlation between LAR and all-cause mortality in patients suffering from liver failure.

METHODS

We retrospectively analyzed data from patients with liver failure who were admitted to the intensive care unit (ICU) between 2008 and 2019, which were gathered from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. LAR was calculated from the ratio obtained from the first measurement taken within 24 h of admission. The optimal LAR threshold was determined using the Youden index. With LAR categorized into low, middle, and high groups based on tertiles, Kaplan - Meier analysis was employed to compare mortality risks among three patient groups. Multivariate Cox proportional hazards regression models were utilized to evaluate the association between LAR and all-cause mortality in hepatic failure patients within hospital admission. Additionally, receiver operating characteristic (ROC) and smoothing curve analysis were used to assess the predictive ability, sensitivity, and specificity of LAR for all-cause mortality in patients with liver failure, and the area under the curve (AUC) was calculated. A smooth curve fitting approach and threshold effect analysis were employed to detect the potentially non-linear relationship between the LAR and the risk of all-cause mortality in patients with hepatic failure. Finally, subgroup analyses were performed to assess the relationship between LAR and prognosis across different types of liver failure.

RESULTS

A total of 902 patients with hepatic failure were included in this study. They were divided into survivors group (611 patients) and non-survivors group (291 patients) according to whether they survived during hospitalization, and the mortality rate of patients was 32.26%. The Kaplan-Meier survival curves illustrating patients in hepatic failure with elevated LAR showed a significantly heightened risk of in-hospital mortality (P < 0.001). We identified a non-linear relationship between LAR and the risk of hospital mortality after adjusting for potential confounders and the inflection point of LAR to be 1.33. LAR was shown to be an independent predictor of all-cause mortality within hospitalization in patients with hepatic failure by multivariate COX regression analysis (HR, 1.66; 95% CI, 1.35-2.05; P < 0.0001). The optimal cutoff value for separating the survival and death groups according to ROC was found to be 0.97. The AUC value for LAR was 0.755 (95% CI: 0.721, 0.789), which was higher than that for arterial blood lactate (AUC = 0.725) and serum albumin (AUC = 0.680) alone. It was not inferior even when compared to MELD (AUC = 0.677).

CONCLUSION

LAR has demonstrated good predictive value for all-cause mortality among liver failure patients in our retrospective study.

Curcumin: A Potential Detoxifier Against Chemical and Natural Toxicants

The human body gets exposed to a variety of toxins intentionally or unintentionally on a regular basis from sources such as air, water, food, and soil. Certain toxins can be synthetic, while some are biological. The toxins affect the various parts of the body by activating numerous pro-inflammatory markers, like oxidative stresses, that tend to disturb the normal function of the organs ultimately. Nowadays, people use different types of herbal treatments, viz., herbal drinks that contain different spices for detoxification of their bodies. One such example is turmeric, the most commonly available spice in the kitchen and used across all kinds of households. Turmeric contains curcumin, which is a natural polyphenol. Curcumin is a medicinal compound with different biological activities, such as antioxidant, antineoplastic, anti-inflammatory, and antibacterial. Hence, this review gives a comprehensive insight into the promising potential of curcumin in the detoxification of heavy metals, carbon tetrachloride, drugs, alcohol, acrylamide, mycotoxins, nicotine, and plastics. The review encompasses diverse animal-based studies portraying curcumin's role in nullifying the different toxic effects in various organs of the body (especially the liver, kidney, testicles, and brain) by enhancing defensive signaling pathways, improving antioxidant enzyme levels, inhibiting pro-inflammatory markers activities and so on. Furthermore, this review also argues over curcumin's safety assessment for its utilization as a detoxifying agent.

Prognostic models in acute liver failure-historic evolution and newer updates "prognostic models in acute liver failure"

Acute liver failure (ALF) is a rare and dynamic syndrome occurring as a sequela of severe acute liver injury (ALI). Its mortality ranges from 50% to 75% based on the aetiology, patients age and severity of encephalopathy at admission. With improvement in intensive care techniques, transplant-free survival in ALF has improved over time. Timely recognition of patients who are unlikely to survive with medical intervention alone is crucial since these individuals may rapidly develop multiorgan failure and render liver transplantation futile. Various predictive models, biomarkers and AI-based models are currently used in clinical practice, each with its fallacies. The King's College Hospital criteria (KCH) were initially established in 1989 to identify patients with acute liver failure (ALF) caused by paracetamol overdose or other causes who are unlikely to improve with conventional treatment and would benefit from a liver transplant. Since then, various models have been developed and validated worldwide. Most models include age, aetiology of liver disease, encephalopathy grade, and liver injury markers like INR, lactate, factor V level, factor VIII/V ratio and serum bilirubin. But none of the currently available models are dynamic and lack accuracy in predicting transplant free survival. There is an increasing interest in developing prognostic serum biomarkers that when used alone or in combination with clinical models enhance the accuracy of predicting outcomes in ALF. Genomics, transcriptomics, proteomics, and metabolomics as well as machine learning and artificial intelligence (AI) algorithms are areas of interest for developing higher-precision predictive models. Overall, the future of prognostic models in ALF is promising, with ongoing research paving the way for more accurate, personalized, and dynamic risk assessment tools that can potentially save lives in this challenging condition. This article summarizes the history of prognostic models in ALF and future trends.

A machine learning model for early candidemia prediction in the intensive care unit: Clinical application

Candidemia often poses a diagnostic challenge due to the lack of specific clinical features, and delayed antifungal therapy can significantly increase mortality rates, particularly in the intensive care unit (ICU). This study aims to develop a machine learning predictive model for early candidemia diagnosis in ICU patients, leveraging their clinical information and findings. We conducted this study with a cohort of 334 patients admitted to the ICU unit at Ji Ning NO.1 people's hospital in China from Jan. 2015 to Dec. 2022. To ensure the model's reliability, we validated this model with an external group consisting of 77 patients from other sources. The candidemia to bacteremia ratio is 1:1. We collected relevant clinical procedures and eighteen key examinations or tests features to support the recursive feature elimination (RFE) algorithm. These features included total bilirubin, age, platelet count, hemoglobin, CVC, lymphocyte, Duration of stay in ICU and so on. To construct the candidemia diagnosis model, we employed random forest (RF) algorithm alongside other machine learning methods and conducted internal and external validation with training and testing sets allocated in a 7:3 ratio. The RF model demonstrated the highest area under the receiver operating characteristic (AUC) with values of 0.87 and 0.83 for internal and external validation, respectively. To evaluate the importance of features in predicting candidemia, Shapley additive explanation (SHAP) values were calculated and results revealed that total bilirubin and age were the most important factors in the prediction model. This advancement in candidemia prediction holds significant promise for early intervention and improved patient outcomes in the ICU setting, where timely diagnosis is of paramount crucial.

Acute liver failure

Acute liver failure (ALF) is a life-threatening disorder characterised by rapid deterioration of liver function, coagulopathy, and hepatic encephalopathy in the absence of pre-existing liver disease. The cause of ALF varies across the world. Common causes of ALF in adults include drug toxicity, hepatotropic and non-hepatotropic viruses, herbal and dietary supplements, antituberculosis drugs, and autoimmune hepatitis. The cause of liver failure affects the management and prognosis, and therefore extensive investigation for cause is strongly suggested. Sepsis with multiorgan failure and cerebral oedema remain the leading causes of death in patients with ALF and early identification and appropriate management can alter the course of ALF. Liver transplantation is the best current therapy, although the role of artificial liver support systems, particularly therapeutic plasma exchange, can be useful for patients with ALF, especially in non-transplant centres. In this Seminar, we discuss the cause, prognostic models, and management of ALF.

Clinical significance of transjugular liver biopsy in acute liver failure - a real-world analysis

BACKGROUND

Histopathological characterization obtained by transjugular liver biopsy (TJLB) may theoretically contribute to clarification of the exact aetiology of acute liver failure (ALF). It's unclear whether the histopathological information from TJLB, due to the small specimen size, significantly contributes to diagnosing ALF causes, guiding therapy decisions, or predicting overall prognosis. This retrospective study aimed to analyse safety and clinical significance of TJLB in patients with ALF.

METHODS

This retrospective, monocentric study investigated safety and efficacy of TJLB in patients with ALF over a ten-year period at a tertiary care transplant-center. The predictive value of various clinical and laboratory characteristics as well as histopathological findings obtained by TJLB on 28-day liver-transplant-free survival were evaluated by calculating uni- and multivariate Cox-proportional hazard regression models. Additional univariate logistic regression analyses were performed to explore the influence of degree of intrahepatic necrosis on the secondary endpoints intensive-care-unit (ICU) admission, need for endotracheal intubation, renal replacement therapy and high-urgency listing for LTX.

RESULTS

A total of 43 patients with ALF receiving TJLB were included into the study. In most cases (n = 39/43 cases) TJLB confirmed the initially already clinically presumed ALF aetiology and the therapeutic approach was unchanged by additional histological examination in the majority of patients (36/43 cases). However, in patients with a high suspicion for aetiologies potentially treatable by medical immunosuppression (e.g. AIH, GvHD), TJLB significantly influenced further treatment planning and/or adjustment. While the degree of intrahepatic necrosis showed significance in the univariate analysis (p = 0.04), it did not demonstrate a significant predictive effect on liver transplant-free survival in the multivariate analysis (p = 0.1). Only consecutive ICU admission was more likely with higher extent of intrahepatic necrosis (Odds ratio (OR) 1.04 (95% CI 1-1.08), p = 0.046).

CONCLUSIONS

Performance of TJLB in ALF led to a change in suspected diagnosis and to a significant change in therapeutic measures only in those patients with a presumed high risk for aetiologies potentially responsive to immunosuppressive therapy. Clinical assessment alone was accurate enough, with additional histopathological examination adding no significant value, to predict overall prognosis of patients with ALF.

Hepatoprotective effects of fruits pulp, seed, and peel against chemical-induced toxicity: Insights from in vivo studies

The liver is a vital organ in human physiology positioned in the upper right quadrant of the peritoneal cavity, which plats a critical role in metabolic processes, detoxification of various substances and overall homeostasis. Along with these critical functions, hepatic diseases impose as significant global health threat. Liver illness is the cause of two million fatalities every year, or 4% of all deaths. Traditionally, healthcare providers have prescribed antibacterial and antiviral medications to address liver illness. Nephrotoxicity is a frequently observed negative reaction to drugs, with the majority of such events happening in individuals who have advanced cirrhosis. Thus, recognizing this gap, there is a dire need of exploration of pharmaceutical alterative for hepatic diseases, with special focus on their efficacy and reduced toxicity. Fruits have long been known to therapeutic impact on human health, thus exploration of fruits components namely pulp, seeds and peels containing phytochemicals have emerged as a promising avenue for hepatoprotective interventions. Thus, review comprehends the information about worldwide burden of chemical induced toxicity and injuries as well as highlight the on-going challenges in hepatic disease management. It also shed light on the valuable contributions fruit parts and their phytocompounds obtained from different components of fruits. Fruit pulp, especially when rich in flavonoids, has demonstrated significant potential in animal model studies. It has been observed to enhance the activity of antioxidant enzymes and reduce the expression of pro-inflammatory markers. The methanolic and ethanolic extracts have demonstrated the most favorable outcomes. Further, this review also discusses about the safety assessments of fruits extracts for their utilization as hepatoprotective agents.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Viral hepatitis-induced acute liver failure

Viral hepatitis-induced acute liver failure (ALF) is a preventable cause for liver-related mortality worldwide. Viruses are the most common cause for ALF in developing nations in contrast to the west, where acetaminophen is largely responsible. Viruses may be hepatotropic or affect the liver secondary to a systemic infection. In tropical countries, infections such as leptospirosis, scrub typhus and malaria can mimic the symptoms of ALF. Differentiating these ALF mimics is crucial because they require etiology-specific therapy. Treatment of viral hepatitis-induced ALF is two-pronged and directed towards providing supportive care to prevent organ failures and antiviral drugs for some viruses. Liver transplantation (LT) is an effective modality for patients deteriorating despite adequate supportive care. Early referral and correct identification of patients who require a transplant are important. Liver support devices and plasma exchange have evolved into "bridging modalities" for LT. Preventive strategies such as hand hygiene, use of clean and potable water and inclusion of vaccines against viral hepatitis in the national program are simple yet very effective methods focusing on the preventive aspect of this disease.

Clinical determinants of hospital mortality in liver failure: a comprehensive analysis of 62,717 patients

BACKGROUND

Liver failure (LF) is characterised by a loss of the synthetic and metabolic liver function and is associated with a high mortality. Large-scale data on recent developments and hospital mortality of LF in Germany are missing. A systematic analysis and careful interpretation of these datasets could help to optimise outcomes of LF.

METHODS

We used standardised hospital discharge data of the Federal Statistical Office to evaluate current trends, hospital mortality and factors associated with an unfavourable course of LF in Germany between 2010 and 2019.

RESULTS

A total of 62,717 hospitalised LF cases were identified. Annual LF frequency decreased from 6716 (2010) to 5855 (2019) cases and was higher among males (60.51%). Hospital mortality was 38.08% and significantly declined over the observation period. Mortality significantly correlated with patients' age and was highest among individuals with (sub)acute LF (47.5%). Multivariate regression analyses revealed pulmonary (ORARDS: 2.76, ORmechanical ventilation: 6.46) and renal complications (ORacute kidney failure: 2.04, ORhepatorenal syndrome: 2.92) and sepsis (OR: 1.92) as factors for increased mortality. Liver transplantation reduced mortality in patients with (sub)acute LF. Hospital mortality significantly decreased with the annual LF case volume and ranged from 47.46% to 29.87% in low- or high-case-volume hospitals, respectively.

CONCLUSIONS

Although incidence rates and hospital mortality of LF in Germany have constantly decreased, hospital mortality has remained at a very high level. We identified a number of variables associated with increased mortality that could help to improve framework conditions for the treatment of LF in the future.

Liver Transplantation for Acute Liver Failure- Indication, Prioritization, Timing, and Referral

Acute liver failure (ALF) is a major success story in gastroenterology, with improvements in critical care and liver transplant resulting in significant improvements in patient outcomes in the current era compared to the dismal survival rates in the pretransplant era. However, the ever-increasing list of transplant candidates and limited organ pool makes judicious patient selection and organ use mandatory to achieve good patient outcomes and prevent organ wastage. Several scoring systems exist to facilitate the identification of patients who need a liver transplant and would therefore need an early referral to a specialized liver unit. The timing of the liver transplant is also crucial as transplanting a patient too early would lead to those who would recover spontaneously receiving an organ (wastage), and a late decision might result in the patient becoming unfit for transplant (delisted) or have an advanced disease which would result in poor post-transplant outcomes. The current article reviews the indications and contraindications of liver transplant in ALF patients, the various prognostic scoring systems, etiology-specific outcomes, prioritization and timing of referral.

175 Years of Bilirubin Testing: Ready for Point-of-Care?

Bilirubin was first detected in blood in 1847 and since then has become one of the most widely used biomarkers for liver disease. Clinical routine bilirubin testing is performed at the hospital laboratory, and the gold standard colorimetric test is prone to interferences. The absence of a bedside test for bilirubin delays critical clinical decisions for patients with liver disease. This clinical care gap has motivated the development of a new generation of bioengineered point-of-care bilirubin assays. In this Perspective, recently developed bilirubin assays are critically discussed, and their translational potential evaluated.

Global burden of Liver Disease: 2023 Update

Liver disease accounts for 2 million deaths and is responsible for 4% of all deaths (1 out of every 25 deaths worldwide); approximately 2/3 of all liver related deaths occur in men. Deaths are largely attributable to complications of cirrhosis and hepatocellular carcinoma, with acute hepatitis accounting for a smaller proportion of deaths. The most common causes of cirrhosis worldwide are related to viral hepatitis, alcohol, and nonalcoholic fatty liver disease (NAFLD). Hepatotropic viruses are the etiological factor in most cases of acute hepatitis, but drug-induced liver injury increasingly accounts for a significant proportion of cases. This iteration of the global burden of liver disease is an update of the 2019 version and focuses mainly on areas where significant new information is available like alcohol-associated liver disease, NAFLD, viral hepatitis, and HCC. We also devote a separate section to the burden of liver disease in Africa, an area of the world typically neglected in such documents.

Prognostic Scores in Acute Liver Failure Due to Viral Hepatitis

Viral infections are among the major causes of acute liver failure (ALF) worldwide. While the role of agents such as hepatitis A, B, C, D and E viruses in precipitating ALF are well known, improvements in serological assays have led to the detection of viral agents such as Epstein Barr virus, cytomegalovirus etc. as atypical causes of ALF. Despite the plethora of literature available on viral hepatitis and ALF, there is very limited large-scale epidemiologic data on the prevalence, risk factors of progression and outcomes in ALF of viral causes. This is important as viral infections remain the leading cause of ALF in the East and in developing countries, while the impact of viral ALF in the West has largely been ameliorated by effective vaccination and sanitization programs. This review focuses specifically on the available prognostic scores that aid in the management of ALF of viral etiologies while also briefly reviewing the current literature on newer viral agents known to cause ALF, risk factors of progression, outcomes and how management algorithms can be developed by incorporation of prognostic scoring systems for referral and transplant listing.

Critical care hepatology: definitions, incidence, prognosis and role of liver failure in critically ill patients

Organ dysfunction or overt failure is a commonplace event in the critically ill affecting up to 70% of patients during their stay in the ICU. The outcome depends on the resolution of impaired organ function, while a domino-like deterioration of organs other than the primarily affected ones paves the way for increased mortality. “Acute Liver Failure” was defined in the 1970s as a rare and potentially reversible severe liver injury in the absence of prior liver disease with hepatic encephalopathy occurring within 8 weeks. Dysfunction of the liver in general reflects a critical event in “Multiple Organ Dysfunction Syndrome” due to immunologic, regulatory and metabolic functions of liver parenchymal and non-parenchymal cells. Dysregulation of the inflammatory response, persistent microcirculatory (hypoxic) impairment or drug-induced liver injury are leading problems that result in “secondary liver failure,” i.e., acquired liver injury without underlying liver disease or deterioration of preexisting (chronic) liver disease (“Acute-on-Chronic Liver Failure”). Conventional laboratory markers, such as transaminases or bilirubin, are limited to provide insight into the complex facets of metabolic and immunologic liver dysfunction. Furthermore, inhomogeneous definitions of these entities lead to widely ranging estimates of incidence. In the present work, we review the different definitions to improve the understanding of liver dysfunction as a perpetrator (and therapeutic target) of multiple organ dysfunction syndrome in critical care.

Graphic Abstract

Management of Acute Liver Failure: Update 2022

Abbreviated pathogenesis and clinical course of the acute liver failure syndrome. The pathogenesis and clinical course of the syndrome of acute liver failure (ALF) differs depending upon the etiology of the primary liver injury. In turn, the severity of the liver injury and resulting synthetic failure is often the primary determinant of whether a patient is referred for emergency liver transplantation. Injuries by viral etiologies trigger the innate immune system via pathogen-associated molecular patterns (PAMPs), while toxin-induced (and presumably ischemia-induced) injuries do so via damage-associated molecular patterns (DAMPs). The course of the clinical syndrome further depends upon the relative intensity and composition of cytokine release, resulting in an early proinflammatory phenotype (SIRS) and later compensatory anti-inflammatory response phenotype (CARS). The outcomes of overwhelming immune activation are the systemic (extrahepatic) features of ALF (cardiovascular collapse, cerebral edema, acute kidney injury, respiratory failure, sepsis) which ultimately determine the likelihood of death.Acute liver failure (ALF) continues to carry a high risk of mortality or the need for transplantation despite recent improvements in overall outcomes over the past two decades. Optimal management begins with identifying that liver failure is indeed present and its etiology, since outcomes and the need for transplantation vary widely across the different etiologies. Most causes of ALF can be divided into hyperacute (ischemia and acetaminophen) and subacute types (other etiologies), based on time of evolution of signs and symptoms of liver failure; the former evolve in 3 to 4 days and the latter typically in 2 to 4 weeks. Both involve intense release of cytokines and hepatocellular contents into the circulation with multiorgan effects/consequences.Management involves optimizing fluid balance and cardiovascular support, including the use of continuous renal replacement therapy, vasopressors, and pulmonary ventilation. Early evaluation for liver transplantation is advised particularly for acetaminophen toxicity, which evolves so rapidly that delay is likely to lead to death.Vasopressor support, high-grade hepatic encephalopathy, and unfavorable (subacute) etiologies heighten the need for urgent listing for liver transplantation. Prognostic scores such as Kings Criteria, Model for End-Stage Liver Disease, and the Acute Liver Failure Group prognostic index take these features into account and provide reasonable but imperfect predictive accuracy. Future treatments may include liver support devices and/or agents that improve hepatocyte regeneration.

The Utility of Early Allograft Dysfunction Components in Determining 90-Day Liver Graft Survival

BACKGROUND

Early allograft dysfunction (EAD) had been established as a useful tool to asses graft and patient survival after liver transplant. We wanted to evaluate effect of EAD components on early graft survival.

METHODS

This retrospective study included 264 patients with EAD after liver transplant in the period between 2015 and 2019. The patients with retransplants were excluded from analyses. The EAD was determined with Olthoff criteria. The logistic regression model was used for analyses. The 90-day graft survival was set as a primary outcome measure.

RESULTS

The main indications for transplant in the analyzed group were hepatitis C virus infection (53 patients, 20.1%), hepatitis B infection (22, 8.3%), primary sclerosing cholangitis (28, 10.1%), and alcoholic liver disease (62, 23.5%), with a median model for end-stage liver disease score of 13.5 points. The 90-day graft loss occurred in 51 patients (19.3%). Each of the components used in EAD diagnosis was found to be correlated with 90-day graft loss. The bilirubin concentration on day 7 (odds ratio [OR], 3.1; 95% CI, 1.4-6.7; P < .001), international normalized ratio on day 7 (OR, 179; 95% CI, 39-815; P < .001), and the natural logarithm of alanine aminotransferase (OR, 3.1; 95% CI, 1.6-6.4) and aspartate aminotransferase (OR, 1.4; 95% CI, 0.4-4.9) predicted 90-day graft loss.

CONCLUSIONS

In patients with EAD, international normalized ratio ≥ 1.6 on day 7 was the strongest predictor of early graft-loss among all EAD components.

Prevalence, severity, duration and resolution of cholestasis after acute liver failure

OBJECTIVE

Persistent cholestasis may follow acute liver failure (ALF), but its course remains unknown. We aimed to describe the prevalence, onset, severity, duration and resolution of post-ALF cholestasis.

DESIGN

Cohort of 127 adult patients with ALF at a liver transplantation centre identified using electronic databases. We obtained laboratory data every 6 hours for the first week, daily until day 30 and weekly, when documented, until day 180.

RESULTS

Median age was 40.7 (IQR 31.0-52.4) years, median peak alanine aminotransferase level was 5494 (2521-8819) U/L and 87 (68.5%) cases had paracetamol toxicity. Overall, 12.6% underwent transplantation (3.4% for paracetamol vs 32.5% for non-paracetamol; p<0.001). Ninety-day mortality was 20.7% for paracetamol versus 30.0% for non-paracetamol patients. All non-transplanted survivors reached a bilirubin level>50 µmol/L, which peaked 3.5 (1.0-10.1) days after admission at 169.0 (80.0-302.0) µmol/L. At hospital discharge, 18.8% of patients had normal bilirubin levels and, at a median follow-up time from admission to last measurement of 16 (10-30) days, 46.9% had normal levels. Similarly, there was an increase in alkaline phosphatase (ALP) (207.0 (148.0-292.5) U/L) and gamma-glutamyl transferase (GGT) (336.0 (209.5-554.5) U/L) peaking at 4.5 days, with normalised values in 40.3% and 8.3% at hospital discharge.

CONCLUSION

Post-ALF cholestasis is ubiquitous. Bilirubin, ALP and GGT peak at 3 to 5 days and, return to baseline in the minority of patients at median follow-up of 16 days. These data inform clinical expectations of the natural course of this condition.

Liver transplantation in acute liver failure: Dilemmas and challenges

Acute liver failure (ALF) refers to a state of severe hepatic injury that leads to altered coagulation and sensorium in the absence of pre-existing liver disease. ALF has different causes, but the clinical characteristics are strikingly similar. In clinical practice, however, inconsistency in the definition of ALF worldwide and confusion regarding the existence of pre-existing liver disease raise diagnostic dilemmas. ALF mortality rates used to be over 80% in the past; however, survival rates on medical treatment have significantly improved in recent years due to a greater understanding of pathophysiology and advances in critical care management. The survival rates in acetaminophen-associated ALF have become close to the post-transplant survival rates. Given that liver transplantation (LT) is an expensive treatment that involves a major surgical operation in critically ill patients and lifelong immunosuppression, it is very important to select accurate patients who may benefit from it. Still, emergency LT remains a lifesaving procedure for many ALF patients. However, there is a lack of consistency in current prognostic models that hampers the selection of transplant candidates in a timely and precise manner. The other problems associated with LT in ALF are the shortage of graft, development of contraindications on the waiting list, vaguely defined delisting criteria, time constraints for pre-transplant evaluation, ethical concerns, and comparatively poor post-transplant outcomes in ALF. Therefore, there is a desperate need to establish accurate prognostic models and explore the roles of evolving adjunctive and alternative therapies, such as liver support systems, plasma exchange, stem cells, auxiliary LT, and so on, to enhance transplant-free survival and to fill the void created by the graft shortage.

Creatinine-lactate score predicts mortality in non-acetaminophen-induced acute liver failure in patients listed for liver transplantation

BACKGROUND

The aim of this study was to analyze prognostic indicators of in-hospital mortality among patients listed for urgent liver transplantation (LT) for non-acetaminophen (APAP)-induced acute liver failure (ALF).

METHODS

ALF patients listed for LT according to the King's College Criteria were retrospectively reviewed. Variables were recorded from medical records and electronic databases (HCMED and RedCap).

RESULTS

The study included 100 patients, of which 69 were subject to LT and 31 died while waiting for LT. Patients were 35.5 ± 14.73 years old, and 78% were females. The main etiologies were virus (17%), drug-induced (32%), autoimmune (15%), and indeterminate hepatitis (31%). The prioritization-to-LT time interval was 1.5 days (0-9). The non-LT patients showed higher lactate (8.71 ± 5.36 vs. 4.48 ± 3.33 mmol/L), creatinine (229 ± 207 vs. 137 ± 136 µm/L), MELD (44 ± 8 vs. 38 ± 8), and BiLE scores (15.8 ± 5.5 vs. 10.3 ± 4.1) compared to LT patients (p < 0.05). Multiple logistic regression analysis identified creatinine and lactate as independent prognostic factors, and a creatinine-lactate (CL) score was developed. ROC analysis showed that creatinine, lactate, MELD, BiLE, and CL scores had considerable specificity (71-88%), but only BiLE, lactate, and CL presented high sensitivities (70%, 80%, and 87% respectively). AUCs were 0.696 for creatinine, 0.763 for lactate, 0.697 for MELD, 0.814 for BiLE, and 0.835 for CL.

CONCLUSIONS

CL and BiLE scores predict mortality with more accuracy than MELD in patients with ALF during prioritization time. Creatinine and lactate are independent prognostic factors for mortality.

Plasma procalcitonin may be an early predictor of liver injury in acetaminophen poisoning: A prospective cohort study

BACKGROUND AND AIMS

Acetaminophen is a common cause of poisoning and liver injury worldwide; however, patient stratification is suboptimal. We aimed to assess the contribution of admission plasma procalcitonin concentration (PCT) to better identify acetaminophen-poisoned patients likely to develop liver injury.

METHODS

We conducted a prospective observational cohort study including all acetaminophen-poisoned patients requiring N-acetylcysteine admitted in a toxicological intensive care unit between 2012 and 2017. Multivariate analysis was performed using a Cox regression model to investigate factors associated with liver injury, defined as an increase in alanine aminotransferase (ALT) >100 IU/L.

RESULTS

One hundred seventeen patients (age, 32 years (21-53), median [25th-75th percentiles]) were included after self-ingesting 16 g (9-30) acetaminophen and received N-acetylcysteine infusion administered within a median 6 h-delay (4-12) from exposure. Co-ingestions were reported in 77% of patients. Rumack-Matthew nomogram was non-interpretable in 47% cases. Liver injury occurred in 38 patients (32%) with a median peak ALT of 2020 IU/L (577-4248). In liver injury patients, admission PCT was significantly increased in comparison to patients without liver injury (21.5 ng/ml (3.2-44.9) versus 0.1 ng/ml (0-0.4), respectively, p < 0.01). The increase in PCT preceded the increase in ALT by 33 h (10-74). In a multivariate analysis, PCT > 1 ng/ml was significantly associated with liver injury (hazard ratio, 7.2 [95% confidence interval, 2.3-22.6; p < 0.001]). PCT (area under the receiver-operating characteristics curve, 0.91 [95%CI: 0.84-0.97]) predicted liver injury with sensitivity, specificity, negative, and positive predictive values of 0.92, 0.84, 0.96, and 0.73, respectively.

CONCLUSION

PCT on admission is associated with liver injury in acetaminophen poisoning. PCT might be used as a predictive tool of liver injury to improve clinical decision-making.

Impact of blood alcohol concentration on hematologic and serum chemistry parameters in trauma patients: Analysis of data from a high-volume level 1 trauma center

Background

Alcohol (EtOH) intoxication is common among trauma patients. While providers are familiar with the clinical aspects of acute EtOH intoxication, few studies have investigated the effects that EtOH levels may have on common laboratory markers. The aim of this study was to identify hematologic and serum chemistry parameters that may be affected by the blood alcohol concentration (BAC), hypothesizing that BAC influences both comprehensive blood count (CBC) and comprehensive serum chemistry (CSC) components.

Methods

We performed an IRB-exempt institutional registry review of all trauma patients who had serum EtOH levels measured between January 2009 and June 2015. Data for each patient included: patient demographics, BAC determinations (g/dL), injury mechanism/severity information (ISS), hematologic parameters included in a CBC (hemoglobin, hematocrit, white blood cell [WBC] count, and platelet count), and CSC panel components (sodium, potassium, chloride, bicarbonate, blood urea nitrogen [BUN], creatinine, glucose, and hepatic function tests). Laboratory markers were contrasted across predefined categories of BAC: <0.10%, 10%-15%, 15%-20%, and >20%. Statistical comparisons were performed using SPSS 18 Software, employing analysis-of-covariance with adjustments performed for the patient demographics and injury characteristics. Statistical significance was set at α = 0.005.

Results

A total of 2167 patient records were analyzed. After adjusting for patient age, gender, and ISS, increasing BAC correlated with 4.8% increase in hemoglobin and 32.5% higher hematocrit (both P < 0.001), as well as a 27.8% decrease in WBC count. There were also statistically significant differences between low (<0.10%) and high (>0.20%) BAC groups across multiple CSC parameters, with largest impact on BUN (32.2% decrease); creatinine (31.5% decrease); and glucose (13.6% decrease) values. Elevated BAC (>0.20 g/dL) was also associated with 81.8% increase in total bilirubin, and hepatic transaminases were elevated among patients with BAC >0.10.

Conclusion

Due to the paucity of literature relating to the effects of BAC on serum hematologic and biochemical markers in acute trauma, this study provides a foundation for further exploration of these relationships and their clinical impact. More specifically, we found that BAC levels significantly influenced key laboratory markers, suggesting that acute EtOH intoxication may lead to hematologic and CSC changes that are potentially important in acute trauma management by frontline clinical staff.

Evaluating lactate prognostic value in children suspected of acetaminophen-induced liver failure in Liberia

BACKGROUND

The prognostic significance of hyperlactatemia in young children with liver injury suspected to be attributed to repeated supratherapeutic doses of acetaminophen remain understudied.

METHODS

We conducted a retrospective medical chart review including children aged <5 years admitted with hepatocellular injury. The study was conducted in Bardnesville Junction Hospital operated by Médecins Sans Frontières in Monrovia, Liberia.

RESULTS

We analyzed 95 children with liver injury in whom a blood lactate measurement on admission was available. Eighty children (84%) were aged <2 years; 49 children (52%) died during hospitalization. The median acetaminophen concentration on admission was 20 mg/L with 60 (70%) children presenting concentrations exceeding 10 mg/L. Median lactate was significantly higher in children who died (10.7 mmol/L; interquartile range (IQR): 8.5-15.7) than those who survived (6.1 mmol/L; IQR: 4.1-8.5), P value < 0.001). The optimal threshold obtained was 7.2 mmol/L with a sensitivity of 84% and specificity 70% (area under curve = 0.80). The previously established thresholds of 3.5 and 4 mmol/L lactate had very low specificity identifying non-survival in children included in this study.

CONCLUSION

In this setting, young children with ALF possibly attributed to acetaminophen toxicity were unlikely to survive if the venous blood lactate concentration exceeded 7.2 mmol/L.

Combining the serum lactic acid level and the lactate clearance rate into the CLIF-SOFA score for evaluating the short-term prognosis of HBV-related ACLF patients

BACKGROUND

Acute-on-chronic liver failure due to hepatitis B virus infection is a subtype of liver failure. The aim of the current study was to investigate the clinical significance of serum lactic acid in combination with the Chronic Liver Failure-Sequential Organ Failure Assessment score (CLIF-SOFA) for evaluating the short-term prognosis of HBV-related ACLF patients.

RESEARCH DESIGN AND METHODS

The serum lactic acid level, the score model for end-stage liver disease (MELD), as well as the CLIF-SOFA of inpatients with HBV-related ACLF who were admitted to the Liver Disease Center of the First Affiliated Hospital of Fujian Medical University between 2009 and 2017 were analyzed.

RESULTS

Three hundred and ninety-one HBV-related ACLF inpatients were measured. In the survival group, the lactate clearance rate measured over the course of 1 week post-admission was significantly higher than that measured for the death group. The area under the curve (AUC) for predicting the prognosis of HBV-related ACLF patients in short-term (within 3-month) with a baseline lactic acid level was 0.776.

CONCLUSIONS

Prediction performance of the short-term prognosis of HBV-related ACLF patients by combining the lactic acid level into the CLIF-SOFA score was significantly improved in comparison to using the CLIF-SOFA score alone.

Fatty liver in pregnancy: a narrative review of two distinct conditions

Introduction: Fatty liver is rather common in pregnancy, occurring in two totally different conditions, i.e. nonalcoholic fatty liver disease (NAFLD) in pregnancy and acute fatty liver of pregnancy (AFLP). The former is a common condition, resulting by chance association because of the epidemics of obesity and the older age of many pregnant women in Western countries; the latter is a rare disease whose pathophysiology is still incompletely understood.Areas covered: We reviewed the evidence-based knowledge on fatty liver in/of pregnancy. For NAFLD, a few large retrospective and prospective studies identify immediate and late risks for both the mother and the fetus. For AFLP, only small retrospective studies are available, indicating that prompt delivery and eventual referral to Liver Units for liver support or transplantation are mandatory to avoid maternal and fetal death.Expert opinion: The number of pregnant women with fatty liver is expected to increase in the next years. Pharmacologic treatment of NAFLD might be postponed, even when new drugs are approved by health authorities for the general population. In the case of AFLP, we need to improve our ability to correctly identify and treat the most severe cases not resolving with delivery.

Acute liver failure

Acute liver failure is a rare and severe consequence of abrupt hepatocyte injury, and can evolve over days or weeks to a lethal outcome. A variety of insults to liver cells result in a consistent pattern of rapid-onset elevation of aminotransferases, altered mentation, and disturbed coagulation. The absence of existing liver disease distinguishes acute liver failure from decompensated cirrhosis or acute-on-chronic liver failure. Causes of acute liver failure include paracetamol toxicity, hepatic ischaemia, viral and autoimmune hepatitis, and drug-induced liver injury from prescription drugs, and herbal and dietary supplements. Diagnosis requires careful review of medications taken, and serological testing for possible viral exposure. Because of its rarity, acute liver failure has not been studied in large, randomised trials, and most treatment recommendations represent expert opinion. Improvements in management have resulted in lower mortality, although liver transplantation, used in nearly 30% of patients with acute liver failure, still provides a life-saving alternative to medical management.

Therapeutic plasma exchange in acute liver failure

BACKGROUND

Multi-organ dysfunction in acute liver failure (ALF) has been attributed to a systemic inflammatory response directly triggered by the injured liver. High-volume therapeutic plasma exchange (HV-TPE) has been demonstrated in a large randomized controlled trial to improve survival. Here, we investigated if a more cost-/ resource effective low-volume (LV) TPE strategy might have comparable beneficial effects.

METHODS

This retrospective study evaluated the effect of LV-TPE on remote organ failure, hemodynamical and biochemical parameters as well as on survival in patients with ALF. Twenty patients treated with LV-TPE in addition to standard medical therapy (SMT) were identified and 1:1 matched to a historical ALF cohort treated with SMT only. Clinical and biochemical parameters were recorded at admission to the intensive care unit and the following 7 days after LV-TPE.

RESULTS

Mean arterial pressure increased following first LV-TPE treatments (d0: 68 [61-75] mm Hg vs d7: 88 [79-98] mm Hg, P = .003) and norepinephrine dose was reduced (d0: 0.264 [0.051-0.906] μg/kg/min vs d3: 0 [0-0.024] μg/kg/min, P = .016). Multi-organ dysfunction was significantly diminished following LV-TPE (CLIF-SOFA d0: 17 [13-20] vs d7: 7 [3-11], P = .001). Thirty-day in-hospital survival was 65% in the LV-TPE cohort and 50% in the SMT cohort (Hazard-ratio for TPE: 0.637; 95% CI: 0.238-1.706, P = .369).

CONCLUSIONS

Patients treated with LV-TPE showed improved surrogate parameters comparable with the effects reported with HV-TPE. These data need to be interpreted with caution due to their retrospective character. Future controlled studies are highly desirable.

Outcomes of liver transplantation for acute fatty liver disease of pregnancy

Acute fatty liver of pregnancy (AFLP) often resolves after pregnancy delivery but can progress to acute liver failure necessitating liver transplantation. We performed a retrospective review of the national Scientific Registry of Transplant Recipients (SRTR) data to identify all women in the United States undergoing liver transplantation (LT) for acute liver failure (ALF) from AFLP from 1991 to 2015, and compared to outcomes in women of childbearing age undergoing transplant for ALF from acetaminophen and ALF from other etiologies. Women with AFLP were likely to be on life support at time of LT and had high rates of renal dysfunction (median Cr 2.1, IQR 1.2-2.3), and hyperbilirubinemia (median bilirubin 17.1, IQR 11.0, 19.9). Although their early and late LT survival outcomes were comparable to the other indications for LT, cumulative 5-year graft survival was numerically lower among AFLP patients (54%, 95% CI, 27-76) compared to APAP (70%, 95% CI, 63-77) and "Other ALF" (76%, 95% CI, 72-80) groups. In conclusion, although AFLP is a rare indication for LT, AFLP patients were as sick or sicker than other women of childbearing age undergoing LT for ALF. Worsened graft survival may be related to higher rates of rejection in the AFLP group.

Outcomes of renal dysfunction in patients with acute liver failure

Background

Although acute kidney injury (AKI) often accompanies acute liver failure (ALF), its impact on long-term outcome is unknown.

Objective

This study examines the incidence, severity and outcomes of AKI in patients with ALF.

Methods

A total of 134 ALF patients treated at Hannover Medical School between 1995 and 2013 were retrospectively analyzed.

Results

Fifty-four ALF patients (40.3%) demonstrated AKI, as defined by the acute kidney injury network (AKIN) classification, on intensive care unit (ICU) admission, and 85 patients (63.4%) developed AKI prior to ALF recovery, emergency liver transplantation (ELT) or death. AKI severity was closely associated with other end-organ damage (p < 0.001). Follow-up creatinine levels in survivors were increased compared to baseline levels (76 versus 64 µmol/l, p = 0.003). One-hundred-and-three (76.9%) patients reached the combined endpoint of ELT or death, and 42 (31.3%) patients died within 28 days. AKIN stage 3 at ICU admission was the strongest independent predictor of 28-day overall mortality (hazard ratio 3.48, 95% confidence interval 1.75-6.93, p < 0.001) and ELT or death (hazard ratio 2.52, 95% confidence interval 1.60-3.96, p < 0.001).

Conclusions

AKI is a frequent complication in ALF that correlates with remote organ damage and long-term creatinine levels and independently predicts outcome.

Early predictors of acute hepatitis B progression to liver failure

BACKGROUND AND AIMS

1~4% of acute hepatitis B (AHB) cases in adults progresses to acute liver failure (ALF).The predictors of ALF and prognosis for patients with ALF are not clear. This study investigated some of predictive and prognostic factors for AHB progression to ALF.

METHODS

A retrospective analysis was used to assess the clinical and laboratory features of 293 patients diagnosed with AHB; the patients were divided into the following two groups: ALF (n = 13) and non-ALF (n = 280).

RESULTS

In total,13 of the 293 (4.43%) patients developed ALF (10 recovered、3 died). The variables of age, anti-HBc IgM titers≥10 S/CO, HBeAg negativity, and total bilirubin (TB) at admission were significantly higher in ALF patients than in non-ALF patients. Compared to non-ALF patients, ALF patients had significantly lower values for prothrombin time activity (PTA), serum albumin, and HBV DNA. At discharge, ALF patients had lower TB normalization rates and much faster clearance of HBsAg, HBeAg and HBVDNA than non-ALF patients. In multivariate analysis, TB≥5×upper limit of normal (ULN) and HBeAg negative status were independent predictors for ALF development at admission, with 84.6% sensitivity, 85.7% specificity, a likelihood ratio of 5.91 and an area under the receiver operating characteristics curve (AUROC) of 0.850.Those who died had lower levels of peak PTA (<20%) and higher levels of peak hepatic encephalopathy (HE) grade (III-IV) than those who recovered.

CONCLUSIONS

Of the patients with ALF, 23.1% died. TB≥5×ULN and HBeAg negative status were the most effective and practicable factors distinguishing ALF from AHB at admission before the onset of encephalopathy. Peak PTA<20% and/or HE grade III-IV were independent predictors of a high probability of death or a need for transplantation.

Modern Management of Acute Liver Failure

Acute liver failure is a rare but life-threatening disease that can lead to progressive encephalopathy, intracranial hypertension, and multiorgan failure. In the developed world, the most common cause remains acetaminophen overdose, but there are still many cases in which there is acute liver failure of unknown etiology. The mainstay of acute liver failure management remains supportive care in the critical care setting. If supportive treatment does not stabilize the disease process, the patient may require emergent liver transplantation. This article summarizes the current management of acute liver failure.

Modified model for end-stage liver disease improves short-term prognosis of hepatitis B virus-related acute-on-chronic liver failure

AIM

To investigate whether the short-term prognosis of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) could be improved by using a modified model for end-stage liver disease (MELD) including serum lactate.

METHODS

This clinical study was conducted at the First Affiliated Hospital, Fujian Medicine University, China. From 2009 to 2015, 236 patients diagnosed with HBV-related ACLF at our center were recruited for this 3-month follow-up study. Demographic data and serum lactate levels were collected from the patients. The MELD scores with or without serum lactate levels from survival and non-survival groups were recorded and compared.

RESULTS

Two hundred and thirty-six patients with HBV-ACLF were divided into two groups: survival group (S) and non-survival group (NS). Compared with the NS group, the patients in survival the S group had a significantly lower level of serum lactate (3.11 ± 1.98 vs 4.67 ± 2.43, t = 5.43, P < 0.001) and MELD score (23.33 ± 5.42 vs 30.37 ± 6.58, t = 9.01, P = 0.023). Furthermore, serum lactate level was positively correlated with MELD score (r = 0.315, P < 0.001). Therefore, a modified MELD including serum lactate was developed by logistic regression analysis (0.314 × lactate + 0.172 × MELD - 5.923). In predicting 3-month mortality using the MELD-LAC model, the patients from the S group had significantly lower baseline scores (-0.930 ± 1.34) when compared with those from the NS group (0.771 ± 1.32, t = 9.735, P < 0.001). The area under the receiver operating characteristic curve (AUROC) was 0.859 calculated by using the MELD-LAC model, which was significantly higher than that calculated by using the lactate level (0.790) or MELD alone (0.818). When the cutoff value was set at -0.4741, the sensitivity, specificity, positive predictive value and negative predictive value for predicting short-term mortality were 91.5%, 80.10%, 94.34% and 74.62%, respectively. When the MELD-LAC scores at baseline level were set at -0.5561 and 0.6879, the corresponding mortality rates within three months were 75% and 90%, respectively.

CONCLUSION

The short-term prognosis of HBV-related ACLF was improved by using a modified MELD including serum lactate from the present 6-year clinical study.

EASL Clinical Practical Guidelines on the management of acute (fulminant) liver failure

The term acute liver failure (ALF) is frequently applied as a generic expression to describe patients presenting with or developing an acute episode of liver dysfunction. In the context of hepatological practice, however, ALF refers to a highly specific and rare syndrome, characterised by an acute abnormality of liver blood tests in an individual without underlying chronic liver disease. The disease process is associated with development of a coagulopathy of liver aetiology, and clinically apparent altered level of consciousness due to hepatic encephalopathy. Several important measures are immediately necessary when the patient presents for medical attention. These, as well as additional clinical procedures will be the subject of these clinical practice guidelines.

Development of a Model to Predict Transplant-free Survival of Patients With Acute Liver Failure

BACKGROUND & AIMS

Patients with acute liver failure (ALF) have a high risk of death that can be substantially reduced with liver transplantation. It is a challenge to predict which patients with ALF will survive without liver transplant because available prognostic scoring systems are inadequate. We devised a mathematical model, using a large dataset collected by the Acute Liver Failure Study Group, which can predict transplant-free survival in patients with ALF.

METHODS

We performed a retrospective analysis of data from 1974 subjects who met criteria for ALF (coagulopathy and hepatic encephalopathy within 26 weeks of the first symptoms, without pre-existing liver disease) enrolled in the Acute Liver Failure Study Group database from January 1, 1998 through June 11, 2013. We randomly assigned the subjects to development and validation cohorts. Data from the development cohort were analyzed to identify factors associated with transplant-free survival (alive without transplantation by 21 days after admission to the study). Statistically significant variables were used to create a multivariable logistic regression model.

RESULTS

Most subjects were women (70%) and white (78%); acetaminophen overdose was the most common cause (48% of subjects). The rate of transplant-free survival was 50%. Admission values of hepatic encephalopathy grade, ALF etiology, vasopressor use, and log transformations of bilirubin and international normalized ratio were significantly associated with transplant-free survival, based on logistic regression analysis. In the validation cohort, the resulting model predicted transplant-free survival with a C statistic value of 0.84, 66.3% accuracy (95% confidence interval, 63.1%-69.4%), 37.1% sensitivity (95% confidence interval, 32.5%-41.8%), and 95.3% specificity (95% confidence interval, 92.9%-97.1%).

CONCLUSIONS

Using data from the Acute Liver Failure Study Group, we developed a model that predicts transplant-free survival of patients with ALF based on easily identifiable hospital admission data. External validation studies are required.

Ability of King's College Criteria and Model for End-Stage Liver Disease Scores to Predict Mortality of Patients With Acute Liver Failure: A Meta-analysis

BACKGROUND & AIMS

Several prognostic factors are used to identify patients with acute liver failure (ALF) who require emergency liver transplantation. We performed a meta-analysis to determine the accuracy of King's College criteria (KCC) versus the model for end-stage liver disease (MELD) scores in predicting hospital mortality among patients with ALF.

METHODS

We performed a systematic search of the literature for articles published from 2001 through 2015 that compared the accuracy of the KCC with MELD scores in predicting hospital mortality in patients with ALF. We identified 23 studies (comprising 2153 patients) and assessed the quality of data, and then performed a meta-analysis of pooled sensitivity and specificity values, diagnostic odds ratios (DORs), and summary receiver operating characteristic curves. Subgroups analyzed included study quality, era, location (Europe vs non-Europe), and size; ALF etiology (acetaminophen-associated ALF [AALF] vs nonassociated [NAALF]); and whether or not the study included patients who underwent liver transplantation and if the study center was also a transplant center.

RESULTS

The DOR for the KCC was 5.3 (95% confidence interval [CI], 3.7-7.6; 57% heterogeneity) and the DOR for MELD score was 7.0 (95% CI, 5.1-9.7; 48% heterogeneity), so the MELD score and KCC are comparable in overall accuracy. The summary area under the receiver operating characteristic curve values was 0.76 for the KCC and 0.78 for MELD scores. The KCC identified patients with AALF who died with 58% sensitivity (95% CI, 51%-65%) and 89% specificity (95% CI, 85%-93%), whereas MELD scores identified patients with AALF who died with 80% sensitivity (95% CI, 74%-86%) and 53% specificity (95% CI, 47%-59%). The KCC predicted hospital mortality in patients with NAALF with 58% sensitivity (95% CI, 54%-63%) and 74% specificity (95% CI, 69%-78%), whereas MELD scores predicted hospital mortality in patients with NAALF with 76% sensitivity (95% CI, 72%-80%) and 73% specificity (95% CI, 69%-78%). In patients with AALF, the KCC's DOR was 10.4 (95% CI, 4.9-22.1) and the MELD score's DOR was 6.6 (95% CI, 2.1-20.2). In patients with NAALF, the KCC's DOR was 4.16 (95% CI, 2.34-7.40) and the MELD score's DOR was 8.42 (95% CI, 5.98-11.88).

CONCLUSIONS

Based on a meta-analysis of studies, the KCC more accurately predicts hospital mortality among patients with AALF, whereas MELD scores more accurately predict mortality among patients with NAALF. However, there is significant heterogeneity among studies and neither system is optimal for all patients. Given the importance of specificity in decision making for listing for emergency liver transplantation, MELD scores should not replace the KCC in predicting hospital mortality of patients with AALF, but could have a role for NAALF.

Liver transplantation in acute liver failure: A challenging scenario

Acute liver failure is a critical medical condition defined as rapid development of hepatic dysfunction associated with encephalopathy. The prognosis in these patients is highly variable and depends on the etiology, interval between jaundice and encephalopathy, age, and the degree of coagulopathy. Determining the prognosis for this population is vital. Unfortunately, prognostic models with both high sensitivity and specificity for prediction of death have not been developed. Liver transplantation has dramatically improved survival in patients with acute liver failure. Still, 25% to 45% of patients will survive with medical treatment. The identification of patients who will eventually require liver transplantation should be carefully addressed through the combination of current prognostic models and continuous medical assessment. The concerns of inaccurate selection for transplantation are significant, exposing the recipient to a complex surgery and lifelong immunosuppression. In this challenging scenario, where organ shortage remains one of the main problems, alternatives to conventional orthotopic liver transplantation, such as living-donor liver transplantation, auxiliary liver transplant, and ABO-incompatible grafts, should be explored. Although overall outcomes after liver transplantation for acute liver failure are improving, they are not yet comparable to elective transplantation.

Circulating levels of soluble receptor for advanced glycation end products and ligands of the receptor for advanced glycation end products in patients with acute liver failure

Animal studies suggest that receptor for advanced glycation end products (RAGE)-dependent mechanisms contribute to acetaminophen-induced liver damage. We examined whether circulating levels of soluble receptor for advanced glycation end products (sRAGE) or RAGE ligands, including extracellular newly identified receptor for advanced glycation end products binding protein (EN-RAGE), high-mobility group box 1 (HMGB1), and Nε-(Carboxymethyl)lysine adducts (CML), could aid in prognostication after an acetaminophen overdose. Sixty well-characterized acetaminophen-related acute liver failure (ALF) patients (30 spontaneous survivors and 30 patients who underwent transplantation and/or died) who were enrolled in the National Institutes of Health-sponsored Acute Liver Failure Study Group, were matched by age, met standard criteria for encephalopathy, and had an international normalized ratio > 1.5 were retrospectively studied. HMGB1, EN-RAGE, CML, and sRAGE were detected by enzyme-linked immunosorbent assay methods in sera from ALF patients and 30 healthy controls. Levels of sRAGE, EN-RAGE, and HMGB1 (but not CML) were significantly greater (P < 0.001) in ALF patients versus normal controls. The levels of sRAGE, HMGB1, and EN-RAGE were significantly higher (P = 0.03, P < 0.01, and P = 0.03) in patients with a systemic inflammatory response syndrome (SIRS) score > 2 versus patients with a SIRS score ≤ 2. Nevertheless, only sRAGE levels were significantly higher in patients who underwent transplantation and/or died versus spontaneous survivors (P < 0.001), and they were positively associated with conventional markers of liver disease severity. Multivariate logistic regression identified an encephalopathy grade > 2 as an independent predictor of an adverse outcome on admission (odds ratio, 13; 95% confidence interval, 2.3-73; P < 0.001). The RAGE-ligand axis may interfere with liver regeneration and should be a promising objective for further research.

Timing and benefit of liver transplantation in acute liver failure

The case for using emergency liver transplantation in acute liver failure was made two decades ago by a series of single centre experiences. The development of models identifying a poor prognosis assisted the selection of patients for liver transplantation but none of these delivers both high sensitivity and specificity for prediction of death. Enhanced sensitivity favours the individual patient while enhanced specificity targets the pool of organs available at those who will derive greatest benefit. The non-transplant survival rates have improved considerably for certain cohorts of patients and these prognostic models have not been adjusted to reflect these changes. The presumption of transplant benefit can no longer be taken as established in paracetamol-related acute liver failure and a policy review is appropriate. In other scenarios, such as seronegative hepatitis and the phenotype of sub-acute liver failure, spontaneous survival rates remain low and the basis for liver transplantation remains sound. Outcomes after liver transplantation are improving but are not yet comparable to elective transplantation. The understanding of factors associated with failure after liver transplantation is improving but accurate definition of futility has not yet been attained.

Role of liver progenitors in acute liver injury

Acute liver failure (ALF) results from the acute and rapid loss of hepatocyte function and frequently exhibits a fulminant course, characterized by high mortality in the absence of immediate state-of-the-art intensive care and/or emergency liver transplantation (ELT). The role of hepatocyte-mediated liver regeneration during acute and chronic liver injury has been extensively investigated, and recent studies suggest that hepatocytes are not exclusively responsible for the regeneration of the injured liver during fulminant liver injury. Liver progenitor cells (LPC) (or resident liver stem cells) are quiescent in the healthy liver, but may be activated under conditions where the regenerative capacity of mature hepatocytes is severely impaired. This review aims to provide an overview of the role of the LPC population during ALF, and the role of putative cytokines, growth factors, mitogens, and hormones in the LPC response. We will highlight the potential interaction among cellular compartments during ALF, and discuss the possible prognostic value of the LPC response on ALF outcomes.

Changing etiology of liver failure in 3,916 patients from northern China: a 10-year survey

PURPOSE

To investigate the etiological characteristics of patients with liver failure in the past 10 years.

METHODS

Clinical and investigational data in hospitalized patients with liver failure admitted from 2002 to 2011 were retrospectively analyzed. Standard definitions and criteria were used to assess disease etiology.

RESULTS

Of these 3,916 patients, 3,429 (87.6 %) had acute-on-chronic liver failure (ACLF), 114 (2.9 %) acute liver failure (ALF), and 373 (9.5 %) subacute liver failure. Viral infection was the most common cause of liver failure in the 3,295 patients (84.1 %). Hepatitis of unknown etiology was deemed responsible for 371 cases of liver failure (9.5 %). Drug-induced liver injury, alcoholic hepatitis, and autoimmune hepatitis led to 120 cases (3.1 %), 109 cases (2.8 %), and 19 cases (0.5 %), respectively. The most common cause of ACLF was HBV infection (87.3 %), while the main causes of acute and subacute liver failure were hepatitis of unknown etiology (39.4 %), viral infection (36.6 %), and drug-induced liver injury (19.3 %). Our data showed that the incidence of liver failure caused by HBV gradually decreased from 86.5 % in 2002 to 69.2 % in 2011. However, the incidence of hepatitis of unknown etiology, drug-induced liver injury, and alcoholic hepatitis was increased.

CONCLUSIONS

HBV infection is the main cause of liver failure in China. However, the incidence of HBV-related liver failure has gradually decreased in the past 10 years. Hepatitis of unknown etiology has replaced HBV infection as the most common apparent cause of acute liver failure.

Circulating microRNAs: promising candidates serving as novel biomarkers of acute hepatitis

Acute liver failure as life threatening condition comprises a difficult diagnostic situation to evaluate potential outcomes and therapeutic options. Thus, prognostic indicators are urgently needed for evaluation of progression of liver injury, clinical outcome, prognosis, and for therapeutic response. Recently, circulating microRNA, in particular miR-122, was described as a potential biomarker of acute liver injury after intoxication of mice. Circulating microRNA (miRNA) molecules are very stable and RNase-resistant due to protein aggregation and vesicle enclosure. Since miRNA species are known to be associated with chronic liver damage or with liver cancer, circulating miRNA patterns are suggested to serve also as reporters for progression of acute liver failure. miRNA profiling analyses using PCR arrays or next generation sequencing, may achieve identification of miRNA species that are linked to the rapid progression of acute liver injury, to the outcome of liver failure, or to the therapeutic response. Therefore, circulating miRNAs are promising, non-invasive biomarkers of future diagnostic approaches. However, normalisation of circulating miRNA levels is essential and further standardisation of miRNA quantification assays is needed.

Prediction of poor outcome in patients with acute liver failure-systematic review of prediction models

INTRODUCTION

Acute liver failure is a rare disease with high mortality and liver transplantation is the only life saving therapy. Accurate prognosis of ALF is crucial for proper intervention.

AIM

To identify and characterize newly developed prognostic models of mortality for ALF patients, assess study quality, identify important variables and provide recommendations for the development of improved models in the future.

METHODS

The online databases MEDLINE® (1950-2012) and EMBASE® (1980-2012) were searched for English-language articles that reported original data from clinical trials or observational studies on prognostic models in ALF patients. Studies were included if they developed a new model or modified existing prognostic models. The studies were evaluated based on an existing framework for scoring the methodological and reporting quality of prognostic models.

RESULTS

Twenty studies were included, of which 18 reported on newly developed models, 1 on modification of the Kings College Criteria (KCC) and 1 on the Model for End-Stage Liver Disease (MELD). Ten studies compared the newly developed models to previously existing models (e.g. KCC); they all reported that the new models were superior. In the 12-point methodological quality score, only one study scored full points. On the 38-point reporting score, no study scored full points. There was a general lack of reporting on missing values. In addition, none of the studies used performance measures for calibration and accuracy (e.g. Hosmer-Lemeshow statistics, Brier score), and only 5 studies used the AUC as a measure of discrimination.

CONCLUSIONS

There are many studies on prognostic models for ALF but they show methodological and reporting limitations. Future studies could be improved by better reporting and handling of missing data, the inclusion of model calibration aspects, use of absolute risk measures, explicit considerations for variable selection, the use of a more extensive set of reference models and more thorough validation.

Prediction of outcome and selection of the liver transplantat candidate in acute liver failure

Acute liver failure (ALF) is characterized by a sudden and severe deterioration of liver function, typically mirrored by a marked increase of the international normalized ratio (INR) and hepatic encephalopathy (HE). Due to various possible causes hepatocytes get damaged via either apoptotic or necrotic pathways. Anticipating the natural prognosis of a patient with ALF is one of the most challenging tasks in hepatology critical care. Important factors that influence the chance of spontaneous recovery are the underlying etiology of acute liver failure, the acuity of disease, and the severity of HE. Once an estimation of the prognosis in the individual patient has been made, this quickly has to be integrated in the discussion whether high-urgency liver transplantation is necessary and justifiable. This decision has to cover several medical, social, and organizational issues. Well organized liver transplantation programs around the world have achieved an impressive improvement of the 1 year survival rate in ALF from around 40% without transplantation up to nearly 80% with transplantation. The recent debate on whether severe acute alcoholic hepatitis could represent a new candidate eligible for high-urgency liver transplantation shows that the topic is still open for discussion.

Angiopoietin-2 in acute liver failure

OBJECTIVE

Angiopoietin-2, an antagonistic ligand of the endothelial Tie2 receptor, has been identified as a gatekeeper of endothelial activation. We examined whether the release of Angiopoietin-2 correlates with surrogates of organ dysfunction and outcome in patients with acute liver failure.

DESIGN

Retrospective clinical and immunohistological study.

SETTING

Intensive care unit of a university hospital.

PATIENTS

Thirty-seven patients with acute liver failure and 20 healthy control subjects.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Angiopoietin-2 levels were measured in sera from 37 patients with acute liver failure on admission and from 20 healthy control subjects. Median age of patients with acute liver failure was 34 yrs, 29 were female, and 21 developed encephalopathy grade 3 or greater. Nine patients survived to day 28 without transplantation, five died without transplantation, and 23 received a transplant. Median (interquartile range) Angiopoietin-2 serum concentrations steadily increased across the following groups: healthy control subjects (1.4 [0.9-1.7] ng/mL), patients with transplant-free recovery (10.0 [4.7-12.1] ng/mL), and patients who reached the composite end point of death or emergency liver transplantation (16.8 [11.3-39.5] ng/mL). Angiopoietin-2 release correlated strongly with surrogate markers of organ dysfunction and disease severity measures (lactate, platelet count, Sequential Organ Failure Assessment score, and Simplified Acute Physiology Score III). Angiopoietin-2 levels were higher in patients with acute kidney injury and patients on mechanical ventilation. Furthermore, Angiopoietin-2 levels were closely associated with Bilirubin-Lactate-Etiology score but not with other liver-specific markers. Unadjusted and adjusted Cox's proportional hazards analyses identified Angiopoietin-2 as a predictor of the composite end point of death or transplantation. Finally, immunohistological studies showed that Angiopoietin-2 protein was upregulated in acute liver failure explants compared with matched liver biopsies obtained at baseline.

CONCLUSIONS

Collectively, our data show that circulating Angiopoietin-2, which potentially originates from the injured liver, correlates with several features of multiple organ dysfunction syndrome and independently predicts outcome. Tie2 agonists may have potential as an endothelium-targeted therapy to ameliorate multiple organ dysfunction syndrome and improve outcome in acute liver failure.

Systematic review: acute liver failure - one disease, more than 40 definitions

BACKGROUND

Acute liver failure (ALF) is a clinical syndrome with very high mortality estimates ranging between 60% and 80%.

AIM

To investigate the explicitness and extent of variability in the used ALF definitions in the ALF prognostic literature.

METHODS

All studies that pertain to the prognosis of patients with ALF were electronically searched in MEDLINE (1950-2012) and EMBASE (1950-2012). Identified titles and abstracts were independently screened by three reviewers to determine eligibility for additional review. We included English articles that reported original data from clinical trials or observational studies on ALF patients.

RESULTS

A total of 103 studies were included. Of these studies 87 used 41 different ALF definitions and the remaining 16 studies did not report any explicit ALF definition. Four components underlying ALF definitions accounted for the differences: presence and/or grading of hepatic encephalopathy (HE); the interval between onset of disease and occurrence of HE; presence of coagulopathy and pre-existing liver disease.

CONCLUSIONS

The diversity in acute liver failure definitions hinders comparability and quantitative analysis among studies. There is room for improvement in the reporting of acute liver failure definitions in prognostic studies. The result of this review may be useful as a starting point to create a uniform acute liver failure definition.

Etiologies and outcomes of acute liver failure in Germany

BACKGROUND & AIMS

Acute liver failure (ALF) is a severe form of acute liver injury that can progress to multiple organ failure. We investigated causes and outcomes of ALF.

METHODS

Eleven university medical centers in Germany were asked to report patients with (primary) severe acute liver injury (sALI) (international normalized ratio [INR] >1.5 but no hepatic encephalopathy) and primary ALF (INR >1.5 with overt hepatic encephalopathy) treated from 2008 to 2009. Data were analyzed from 46 patients with sALI and 109 patients with ALF.

RESULTS

The most frequent etiologies of primary ALF were non-acetaminophen drug-induced (32%), indeterminate (24%), and viral (21%); acetaminophen ingestion was the cause of ALF in only 9% of patients. The support of a ventilator was required by 44% of patients with ALF, vasopressors by 38%, and renal replacement by 36%. Seventy-nine patients with ALF (72%) survived until hospital discharge, 38 (35%) survived without emergency liver transplantation (ELT), and 51 received ELT (47%); 80% of patients who received ELT survived until discharge from the hospital.

CONCLUSIONS

In Germany, drug toxicity, indeterminate etiology, and viral hepatitis appear to be the major causes of primary ALF, which has high mortality. Patients with ALF are at great risk of progressing to multiple organ failure, but 80% of patients who receive ELT survive until discharge from the hospital.