The sequential organ failure assessment (SOFA) score is prognostically superior to the model for end-stage liver disease (MELD) and MELD variants following paracetamol (acetaminophen) overdose

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.

Issues of intensive care and liver transplantation tactics in fulminant liver failure

Fulminant liver failure is usually characterized as severe acute liver injury with encephalopathy and synthetic dysfunction (international normalized ratio [INR] ≥1.5) in a patient without cirrhosis or previous liver disease. Management of patients with acute liver failure includes ensuring that the patient is cared for appropriately, monitoring for worsening liver failure, managing complications, and providing nutritional support. Patients with acute liver failure should be treated at a liver transplant center whenever possible. Serial laboratory tests are used to monitor the course of a patient's liver failure and to monitor for complications. It is necessary to monitor the level of aminotransferases and bilirubin in serum daily. More frequent monitoring (three to four times a day) of blood coagulation parameters, complete blood count, metabolic panels, and arterial blood gases should be performed. For some causes of acute liver failure, such as acetaminophen intoxication, treatment directed at the underlying cause may prevent the need for liver transplantation and reduce mortality. Lactulose has not been shown to improve overall outcomes, and it can lead to intestinal distention, which can lead to technical difficulties during liver transplantation. Early in acute liver failure, signs and symptoms of cerebral edema may be absent or difficult to detect. Complications of cerebral edema include increased intracranial pressure and herniation of the brain stem. General measures to prevent increased intracranial pressure include minimizing stimulation, maintaining an appropriate fluid balance, and elevating the head of the patient's bed. For patients at high risk of developing cerebral edema, we also offer hypertonic saline prophylaxis (3%) with a target serum sodium level of 145 to 155 mEq/L (level 2C). High-risk patients include patients with grade IV encephalopathy, high ammonia levels (>150 µmol/L), or acute renal failure, and patients requiring vasopressor support. Approximately 40 % of patients with acute liver failure recover spontaneously with supportive care. Predictive models have been developed to help identify patients who are unlikely to recover spontaneously, as the decision to undergo liver transplant depends in part on the likelihood of spontaneous recovery of the liver. However, among those who receive a transplant, the one-year survival rate exceeds 80 %, making this treatment the treatment of choice in this difficult patient population.

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.

[Acute Liver Failure: Current Updates and Management]

Acute liver failure (ALF) is a rare disease condition with a dynamic clinical course and catastrophic outcomes. Several etiologies are involved in ALF. Hepatitis A and B infections and indiscriminate use of untested herbs or supplemental agents are the most common causes of ALF in Korea. Noninvasive neurological monitoring tools have been used in patients with ALF in recent times. Ongoing improvements in intensive care, including continuous renal replacement therapy, therapeutic plasma exchange, vasopressor, and extracorporeal membrane oxygenation, have reduced the mortality rate of patients with ALF. However, liver transplantation is still the most effective treatment for patients with intractable ALF. There is a need for further research in the areas of better prognostication and precise selection of patients for emergency transplantation.

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

Comparison of Scoring Systems in Predicting Severity and Prognosis of Hypertriglyceridemia-Induced Acute Pancreatitis

BACKGROUND

In China, hyperlipidemia is the second major reason of acute pancreatitis.

AIMS

Comparison of Scoring Systems in identification patients at risk for severe acute pancreatitis (SAP), pancreatic necrosis (PNec), and infected pancreatic necrosis (IPN) early in the course of hypertriglyceridemia-induced acute pancreatitis (HTG-AP).

METHODS

Predictive accuracy of scoring systems was measured by the area under the receiver operating characteristic curve (AUC) in a retrospective study. Pairwise AUC comparisons were performed to calculate the difference between scoring systems.

RESULTS

A total of 238 patients diagnosed with HTG-AP were included. Sixty patients (25.2%) were classified as SAP. Twenty-nine patients (12.2%) had evidence of PNec. Nine patients (3.8%) were diagnosed with IPN. One patient (0.4%) died during hospitalization. In predicting SAP in HTG-AP, the AUCs of APACHE-II, SOFA, SIRS, Ranson's, BISAP, and MMS were 0.77, 0.83, 0.73, 0.88, 0.83, and 0.85, respectively; in predicting PNec, were 0.75, 0.77, 0.75, 0.86, 0.80, and 0.75, respectively; and in predicting IPN, were 0.92, 0.86, 0.76, 0.85, 0.84, and 0.87, respectively. Pairwise AUC comparisons revealed that Ranson's, MMS, BISAP, and SOFA had higher accuracy than SIRS, Ranson's and MMS had higher accuracy than APACHE-II in predicting SAP; Ranson's had the same accuracy with BISAP, but higher than other four criteria in predicting PNec; APACHE-II had higher accuracy than SIRS in predicting IPN.

CONCLUSIONS

APACHE-II had high performance in predicting IPN, and all other score systems had medium performance in predicting SAP, PNec, and IPN in HTG-AP. Each score has its merit and weakness; BISAP may be the best criterion in predicting severity and prognosis of HTG-AP.

Beyond KCH selection and options in acute liver failure

The King’s prognostic criteria for patients with acute liver failure (ALF) introduced in 1989 have been used worldwide. This distinguished for the first time cases with ‘hyper-acute’ course (characteristically paracetamol overdose) where there is a better chance of recovery with medical supportive care alone from those etiologies with a less acute course and paradoxically lower chances of ‘spontaneous’ recovery. Ongoing use showed the limited sensitivity of the criteria to constitute a significant practical limitation. Subsequent models including the MELD score and composite ones with markers of necrosis, an apoptotic liver cell death, proposed to improve sensitivity did not have the required high specificity. Two recent models utilizing new availability of web- and app-based computing delivering outcome predication through sophisticated algorithms are described. The first is a dynamic model described for paracetamol-induced ALF based upon admission findings and sequential variables over the first 2 days. The new model of the US Acute Liver Failure group was devised to cover all etiologies of ALF for predicting ‘transplant-free’ survival and accurately predicated spontaneous survival in two-thirds of cases. Improved survival results with medical management, particularly in hyper-acute cases, now approach those obtained with successful liver transplant and have raised the question of transplant benefit. Also considered in the review are new non-transplant approaches to treatment including the use of plasma exchange and based on successful results in acute-on-chronic liver failure, agents to modulate and improve hepatic regeneration.

Non-Intensive Care Unit Management of Acute Liver Failure

Acute liver failure (ALF) is an uncommon syndrome with a highly variable and unpredictable clinical course. The initial diagnostic evaluation is typically performed in a non-intensive care unit (ICU) setting, like the emergency department or general hospital ward. Prompt restoration of intravascular volume with intravenous fluids and correction of electrolyte, metabolic, and acid-base disturbances are important initial interventions in the management of ALF and can be safely accomplished in non-ICU settings in many patients. Similarly, therapies such as administration of N-acetylcysteine for acetaminophen-induced ALF and other cause-specific interventions can also be administered in non-ICU settings, thus minimizing delay.

Acetaminophen (APAP or N-Acetyl-p-Aminophenol) and Acute Liver Failure

Acetaminophen (APAP) is the leading cause of acute liver failure (ALF), although the worldwide frequency is variable. APAP hepatotoxicity develops either following intentional overdose or unintentional ingestion (therapeutic misadventure) in the background of several factors, such as concomitant use of alcohol and certain medications that facilitate the formation of reactive and toxic metabolites. Spontaneous survival is more common in APAP-induced ALF compared with non-APAP etiologies. N-acetylcysteine is recommended for all patients with APAP-induced ALF and it reduces mortality. Liver transplantation should be offered early to those who are unlikely to survive based on described prognostic criteria.

Risk stratification tools in emergency general surgery

The use of risk stratification tools (RST) aids in clinical triage, decision making and quality assessment in a wide variety of medical fields. Although emergency general surgery (EGS) is characterized by a comorbid, physiologically acute patient population with disparately high rates of perioperative morbidity and mortality, few RST have been explicitly examined in this setting. We examined the available RST with the intent of identifying a tool that comprehensively reflects an EGS patients perioperative risk for death or complication. The ideal tool would combine individualized assessment with relative ease of use. Trauma Scoring Systems, Critical Care Scoring Systems, Surgical Scoring Systems and Track and Trigger Models are reviewed here, with the conclusion that Emergency Surgery Acuity Score and the American College of Surgeons National Surgical Quality Improvement Programme Universal Surgical Risk Calculator are the most applicable and appropriate for EGS.

Risk factors for mortality in patients with low lactate level and septic shock

BACKGROUND

According to the new definition of septic shock, vasopressor therapy and hyperlactatemia are essential for diagnosis. However, there is controversy regarding the cutoff value for lactate, and prognostic factors in patients with septic shock and hypolactatemia. This study evaluated the prognostic significance of the cutoff value for lactate level in septic shock patients.

METHODS

The retrospective observational cohort study enrolled 1043 patients aged ≥18 years who meet the revised definition of septic shock. Clinical outcomes of patients with hyperlactatemia were compared with hypolactatemia.

RESULTS

Of the 1022 eligible patients, 369 had an arterial lactate level ≤2 mmol/L. More patients in the high lactate group had poor prognosis than in the low lactate group. A high Sequential Organ Failure Assessment score (SOFA) score group was significant (p < 0.001) in predicting lactate levels. On the subgroup analysis of risk factors affecting mortality in the low lactate group, high Acute Physiology And Chronic Health Evaluation Ⅱ (APACHEⅡ) score (p = 0.003), high C-reactive protein (p = 0.034), and chronic heart failure (p = 0.001) were independently associated with 28-day mortality.

CONCLUSION

Arterial lactate is a very reliable diagnostic and prognostic predictor of septic shock. However, despite low arterial lactate, patients with a high APACHEⅡ score, high C-reactive protein levels, and chronic heart failure had a poorer prognosis.

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.

Patients with the worst outcomes after paracetamol (acetaminophen)-induced liver failure have an early monocytopenia

BACKGROUND

Acute liver failure (ALF) is associated with significant morbidity and mortality. Studies have implicated the immune response, especially monocyte/macrophages as being important in dictating outcome.

AIM

To investigate changes in the circulating monocytes and other immune cells serially in patients with ALF, relate these with cytokine concentrations, monocyte gene expression and patient outcome.

METHODS

In a prospective case-control study in the Scottish Liver Transplant Unit, Royal Infirmary Edinburgh, 35 consecutive patients admitted with paracetamol-induced liver failure (POD-ALF), 10 patients with non-paracetamol causes of ALF and 16 controls were recruited. The peripheral blood monocyte phenotype was analysed by flow cytometry, circulating cytokines quantified by protein array and monocyte gene expression array performed and related to outcome.

RESULTS

On admission, patients with worst outcomes after POD-ALF had a significant monocytopenia, characterised by reduced classical and expanded intermediate monocyte population. This was associated with reduced circulating lymphocytes and natural killer cells, peripheral cytokine patterns suggestive of a 'cytokine storm' and increased concentrations of cytokines associated with monocyte egress from the bone marrow. Gene expression array did not differentiate patient outcome. At day 4, there was no significant difference in monocyte, lymphocyte or natural killer cells between survivors and the patients with adverse outcomes.

CONCLUSIONS

Severe paracetamol liver failure is associated with profound changes in the peripheral blood compartment, particularly in monocytes, related with worse outcomes. This is not seen in patients with non-paracetamol-induced liver failure. Significant monocytopenia on admission may allow earlier clarification of prognosis, and it highlights a potential target for therapeutic intervention.

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.

Aberrant GSTP1 promoter methylation predicts short-term prognosis in acute-on-chronic hepatitis B liver failure

BACKGROUND

Glutathione-S-transferase P1 (GSTP1) methylation has been demonstrated to be associated with oxidative stress induced liver damage in acute-on-chronic hepatitis B liver failure (ACHBLF).

AIM

To evaluate the methylation level of GSTP1 promoter in acute-on-chronic hepatitis B liver failure and determine its predictive value for prognosis.

METHODS

One hundred and five patients with acute-on-chronic hepatitis B liver failure, 86 with chronic hepatitis B (CHB) and 30 healthy controls (HC) were retrospectively enrolled. GSTP1 methylation level in peripheral mononuclear cells (PBMC) was detected by MethyLight. Clinical and laboratory parameters were obtained.

RESULTS

GSTP1 methylation levels were significantly higher in patients with acute-on-chronic hepatitis B liver failure (median 16.84%, interquartile range 1.83-59.05%) than those with CHB (median 1.25%, interquartile range 0.48-2.47%; P < 0.01) and HC (median 0.80%, interquartile range 0.67-1.27%; P < 0.01). In acute-on-chronic hepatitis B liver failure group, nonsurvivors showed significantly higher GSTP1 methylation levels (P < 0.05) than survivors. GSTP1 methylation level was significantly correlated with total bilirubin (r = 0.29, P < 0.01), prothrombin time activity (r = -0.24, P = 0.01) and model for end-stage liver disease (MELD) score (r = 0.26, P = 0.01). When used to predict 1- or 2-month mortality of acute-on-chronic hepatitis B liver failure, GSTP1 methylation showed significantly better predictive value than MELD score [area under the receiver operating characteristic curve (AUC) 0.89 vs. 0.72, P < 0.01; AUC 0.83 vs. 0.70, P < 0.05 respectively]. Meanwhile, patients with GSTP1 methylation levels above the cut-off points showed significantly poorer survival than those below (P < 0.05).

CONCLUSIONS

Aberrant GSTP1 promoter methylation exists in acute-on-chronic hepatitis B liver failure and shows high predictive value for short-term mortality. It might serve as a potential prognostic marker for acute-on-chronic hepatitis B liver failure.

Circulating Kidney Injury Molecule 1 Predicts Prognosis and Poor Outcome in Patients With Acetaminophen-Induced Liver Injury

Acute kidney injury in the context of acetaminophen (APAP; paracetamol)-induced liver injury is an important predictor of the requirement for urgent liver transplantation (LT) to avoid death. However, the prognostic biomarker used to report kidney dysfunction (serum creatinine concentration) has suboptimal sensitivity and specificity. Kidney injury molecule 1 (KIM-1) can be quantified in plasma as a sensitive and specific biomarker of kidney injury in both clinical and preclinical studies. Therefore, plasma KIM-1 has potential as a sensitive prognostic biomarker of patient outcome post-APAP overdose. In a cohort of APAP overdose patients (N = 74) with and without established liver injury, we quantified plasma KIM-1 by immunoassay on the first day of admission to a LT unit and assessed its diagnostic performance to predict outcome compared with serum creatinine concentration. Day 1 plasma KIM-1 was significantly elevated in patients that died or required LT, compared to spontaneous survivors (1,182 ± 251 vs. 214 ± 45 pg/mL; P < 0.005). Receiver operator characteristic analysis demonstrated the superiority of KIM-1 (area under the curve [AUC]: 0.87; 95% confidence interval [CI]: 0.78-0.95; 0.56 sensitivity at 0.95 specificity), compared with serum creatinine (AUC, 0.76; 95% CI: 0.64-0.87; 0.08 sensitivity at 0.95 specificity) and other current prognostic indicators, when measured on the first day of enrollment into the study. Furthermore, KIM-1 was found to be a statistically significant independent predictor of outcome at the 5% level (P < 0.0386) in a multivariable logistic regression model that considered all measured factors (pseudo-R^2 = 0.895).

CONCLUSION

Early measurement of plasma KIM-1 represents a more sensitive predictor of patient outcome than serum creatinine concentration post-APAP overdose. With further development, plasma KIM-1 could significantly improve prognostic stratification.

An elevated neutrophil-lymphocyte ratio is associated with adverse outcomes following single time-point paracetamol (acetaminophen) overdose: a time-course analysis

BACKGROUND

The innate immune system is profoundly dysregulated in paracetamol (acetaminophen)-induced liver injury. The neutrophil-lymphocyte ratio (NLR) is a simple bedside index with prognostic value in a number of inflammatory conditions.

AIM

To evaluate the prognostic accuracy of the NLR in patients with significant liver injury following single time-point and staggered paracetamol overdoses.

PATIENTS AND METHODS

Time-course analysis of 100 single time-point and 50 staggered paracetamol overdoses admitted to a tertiary liver centre. Timed laboratory samples were correlated with time elapsed after overdose or admission, respectively, and the NLR was calculated.

RESULTS

A total of 49/100 single time-point patients developed hepatic encephalopathy (HE). Median NLRs were higher at both 72 (P=0.0047) and 96 h after overdose (P=0.0041) in single time-point patients who died or were transplanted. Maximum NLR values by 96 h were associated with increasing HE grade (P=0.0005). An NLR of more than 16.7 during the first 96 h following overdose was independently associated with the development of HE [odds ratio 5.65 (95% confidence interval 1.67-19.13), P=0.005]. Maximum NLR values by 96 h were strongly associated with the requirement for intracranial pressure monitoring (P<0.0001), renal replacement therapy (P=0.0002) and inotropic support (P=0.0005). In contrast, in the staggered overdose cohort, the NLR was not associated with adverse outcomes or death/transplantation either at admission or subsequently.

CONCLUSION

The NLR is a simple test which is strongly associated with adverse outcomes following single time-point, but not staggered, paracetamol overdoses. Future studies should assess the value of incorporating the NLR into existing prognostic and triage indices of single time-point paracetamol overdose.

Acetaminophen-related hepatotoxicity

Acetaminophen (APAP) is the leading worldwide cause of drug overdose and acute liver failure (ALF). Single overdose ingestion and therapeutic misadventure may cause hepatotoxicity. Several factors, such as concomitant alcohol use or abuse, concurrent medications, genetic factors, and nutritional status, can influence the susceptibility and severity of APAP hepatotoxicity. Early manifestations of APAP hepatotoxicity are nonspecific, but require prompt recognition by physicians. Patients with repeated overdose tend to present late, and in such hepatotoxicity may have already evolved. N-acetylcysteine is a very effective antidote when giving within 8 hours, and is also recommended after a presentation of hepatotoxicity and ALF. The prognosis of patients with APAP-induced ALF is better than other causes of ALF. Liver transplantation should be offered to those who are unlikely to survive.

Introducing an optimal liver allocation system for liver cirrhosis patients

BACKGROUND

Liver transplantation (LT) is the only treatment option for patients with advanced liver disease. Currently, liver donation to these patients, considering priorities, is based on the Model for End-Stage Liver Disease (MELD). MELD score is a tool for predicting the risk of mortality in patients with advanced liver disease. However, few studies have so far been conducted in Iran on the efficacy of MELD score of these patients.

OBJECTIVES

This study reviews the present status of the MELD score and introduces a new model for optimal prediction of the risk of mortality in Iranian patients with advanced liver disease.

PATIENTS AND METHODS

Data required were collected from 305 patients with advanced liver disease who enrolled in a waiting list (WL) in Imam Khomeini Hospital from May 2008 to May 2009. All of the patients were followed up for at least 3 years until they died or underwent LT. Cox regression analysis was applied to select the factors affecting their mortality. Survival curves were plotted. Wilcoxson test and receiver operating characteristics curves for survival predictive model were used to compare the scores. All calculations were performed with the SPSS (version 13.0) and R softwares.

RESULTS

During the study, 71 (23.3%) patients died due to liver cirrhosis and 43 (14.1%) underwent LT. Viral Hepatitis (43.7%) is the most common cause of end-stage liver disease among Iranian patients. A new model (NMELD) was proposed with the use of the natural logarithms of two blood serum variables (total bilirubin and albumin) and the patients' age (year) by applying the Cox model: NMELD = 10 × (0.736 × ln (bilirubin) - 1.312 × ln (albumin) + 0.025 × age + 1.776).

CONCLUSIONS

The results of the Wilcoxon test showed that there is a significant difference between the usual MELD and our proposed NMELD scores (P < 0.001). Receiver operating characteristics curve for survival predictive model indicated that the NMELD score is more efficient compared with the MELD score in predicting the risk of mortality. Since serum creatinine was not significant in NMELD score, further studies to clarify this issue are suggested.

Persistently elevated troponin I in paracetamol hepatotoxicity: association with liver injury, organ failure, and outcome

CONTEXT

An elevated troponin I (TnI) is associated with a poorer prognosis during critical illness.

OBJECTIVE

Our aims were to determine whether significant paracetamol-induced hepatotoxicity was associated with an elevated TnI; if this elevation was persistent and was associated with worse clinical outcomes.

MATERIALS AND METHODS

In this retrospective cohort study, the requirement for orthotopic liver transplantation (OLT) or death and/or the development of multiorgan failure (MOF) was evaluated for 48 consecutive patients admitted to the Royal Infirmary of Edinburgh (a university tertiary referral centre) with acute liver injury or acute liver failure secondary to paracetamol overdose.

RESULTS

TnI was elevated (≥ 0.05 ng/L) in 13/48 patients (27%). This appeared to be sustained for at least 6 days which has not been shown previously in the context of Acute Liver Injury (ALI). Elevated TnI was strongly associated with MOF, with the requirement for inotropic support being the strongest predictor (p = 0.003, OR 9.00, 95% CI 2.13-37.98). TnI elevations also correlated strongly with Acute Physiology and Chronic Health Evaluation (APACHE) II scores (p = 0.0006, r = 0.482, 95% CI 0.22-0.68) and with interleukin 6 (IL-6) levels (p = 0.0001, r = 0.55, 95% CI 0.29-0.73). Although a raised TnI was associated with a markedly increased risk of death or orthotopic liver transplant (p = 0.005, OR 7.73, 95% CI 1.87-32.05) on univariate analysis, this was primarily seen in the context of MOF (SOFA score p = 0.003, OR 1.23, 95% CI 1.07-1.41) and was not an independent predictor of death. There was no correlation between TnI or outcome with other cardiac biomarkers and markers of cardiovascular risk.

DISCUSSION AND CONCLUSION

An elevated TnI in the context of acute liver injury or liver failure following paracetamol overdose is associated with a significantly worse patient outcome but it is not an independent prognostic factor. Further studies should be undertaken to investigate the mechanism behind this elevated troponin association.

Liver transplantation in acute-on-chronic liver failure patients with high model for end-stage liver disease (MELD) scores: a single center experience of 100 consecutive cases

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a severe clinical condition for which liver transplantation (LT) is the only curative option. However, there are little published data on risk factors and outcomes of LT for ACLF.

METHODS

The objective of this study was to analyze preoperative, intraoperative, postoperative, and overall survival data on 100 consecutive cases with ACLF in order to try to determine for which patients LT are futile.

RESULTS

One hundred consecutive patients with pathology-confirmed ACLF who underwent LT from June 2004 to September 2012 were enrolled. The preoperative data showed that all patients were in a serious condition with a median high model for end-stage liver disease (MELD) score of 32, total bilirubin of 440.20 umol/L, international normalized ratio (INR) of 3.012, and at least one organ dysfunction as assessed by a Sequential Organ Failure Assessment (SOFA) score of ≥9. The patients had either deceased or a living donor LT with an overall mortality of 20%. The 1-, 3-, and 5-year cumulative survival rates were 76.8%, 75.6%, and 74.1%, respectively, and graft 1-, 3-, and 5-y accumulative survival rates were 73.3%, 72.1%, and 70.6%, respectively. However, the area under receiver operating characteristic of SOFA score, MELD score, as well as Child-Pugh score were 0.552, 0.547, and 0.547, respectively.

CONCLUSIONS

Both deceased and living donor LT are effective therapeutic options for patients with ACLF and the short- and long-term survival rates are encouraging. It is important to conduct more prospective and multi-center studies to define preoperatively which patients would benefit from LT.

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.