A. James Hanje

Preoperative evaluation of patients with liver disease

Patients with end-stage liver disease often undergo surgery for indications other than liver transplantation. These patients have an increased risk of morbidity and mortality that is related to their underlying liver disease. Assessments of surgical risk provide a basis for discussion of risks and benefits, treatment decision making, and for optimal management of patients for whom surgery is planned. The most useful indicators of surgical risk are indices that predict advanced disease, such as the Child–Turcotte–Pugh score, or those that predict prognosis, such as the Model for End-stage Liver Disease score. Careful preoperative risk assessment, patient selection, and management of various manifestations of advanced disease might decrease morbidity and mortality from nontransplant surgery in patients with liver disease.

Outcomes in Adults With Acute Liver Failure Between 1998 and 2013: An Observational Cohort Study.

Context Whether changes have occurred in the causes of acute liver failure (ALF), its management, or the survival of patients with the condition (with or without liver transplantation) is not known. Contribution This large cohort study found that despite similar causes and severity of ALF among patients referred to specialty centers from 1998 to 2013, the proportion of patients listed for liver transplantation decreased and survival improved among those who did not receive a transplant as well as those who did. Implication More study is warranted to better understand the specific changes in care that may have led to improved survival of patients with ALF. Acute liver failure (ALF) is defined as severe liver injury with rapid onset that results in hepatic encephalopathy (HE) and coagulopathy in persons without preexisting liver disease. The principal causes of ALF include acetaminophen (N-acetyl-p-aminophenol [APAP]) overdose, ischemic and pregnancy-associated liver injury, acute infection with hepatitis A or B virus, drug-induced liver injury, autoimmune hepatitis, BuddChiari syndrome, and Wilson disease (1, 2). For some causes, such as APAP toxicity, outcomes are favorable and transplant-free survival (TFS) approaches 70%, whereas other causes have unfavorable outcomes, including a much lower likelihood (<30%) of recovery without liver transplantation (2). One-year survival after emergency liver transplantation in patients with ALF in the United States and Europe is reportedly good but is lower than among patients with cirrhosis who receive a transplant (3). Patients with ALF often deteriorate rapidly and therefore receive the most urgent ranking (status 1) in the United Network for Organ Sharing transplantation system. Treatment of ALF in the intensive care unit is largely supportive and includes ventilator and vasopressor support for respiratory and/or circulatory failure, renal replacement therapy, plasma and blood transfusions, antibiotics, and measures to decrease intracranial pressure (46). N-acetylcysteine is used to treat APAP overdose and has shown efficacy in patients with ALF not due to APAP toxicity, particularly those referred early and having only mild HE (7). However, few disease-specific or general treatments are available that yield improved outcomes. In this study, our aim was to update the U.S. experience with ALF at specialized liver disease and transplant centers since the last published overview by the Acute Liver Failure Study Group (ALFSG) in 2002 (2). This group initiated its registry in January 1998 to better characterize the causes, clinical features, and outcomes of this super-orphan condition and aimed to enroll cases prospectively from participating liver transplant centers across North America. Accordingly, we analyzed data on all patients with ALF enrolled between 1998 and 2013, focusing on whether clinical features or outcomes of the ALF syndrome have changed over time. In addition, we sought to determine the relationship between ALF causes and rates of TFS and whether utilization of liver transplantation changed in the 16-year observation period. Methods Study Population From 1 January 1998 through 31 December 2013, adult patients were consecutively enrolled in the ALFSG registry (2) from 31 U.S. academic liver centers (of which only 5 legacy sites participated continuously throughout the 16-year period). All enrolled patients had both coagulopathy (international normalized ratio [INR] 1.5) and any grade of HE (as clinically defined by the classic West Haven criteria [8]) within 26 weeks of the first symptoms and had no evidence of significant chronic liver disease, especially cirrhosis. Patients for whom prior liver transplantation failed (due to primary graft nonfunction or other causes) were excluded. During the 16-year period, the number of sites participating, their geographic locations, and the number of cases contributed per site varied depending on each sites ability to continually identify and enroll patients over time (Appendix Figure 1). Appendix Figure 1. Site enrollment over time. Patients were usually admitted to intensive care units; 82.4% were hospitalized before transfer to the referral tertiary care study site, and the remainder were admitted directly to the study site. All were screened for inclusion according to the ALF criteria defined earlier. Written informed consent was obtained from the legal next of kin. A log of screen failures and consent refusal was maintained. All centers complied with local institutional review board requirements. Data Management and Integrity At enrollment into the study, we prospectively collected patient demographic characteristics (age, sex, race, and ethnicity); a complete medical history, including the timing of the first symptom of ill health, onset of jaundice and HE, and the number of days between the first symptom, hospital admission, transfer to the study site (where relevant), and enrollment in the study; and clinical features, including blood pressure and need for vasopressor support, mechanical ventilation, and renal replacement therapy, which allowed calculation of the systemic inflammatory response syndrome (SIRS) score (9). We also collected standard liver and metabolic test results and clinical data daily for up to 7 days, as well as serologic and other tests to determine the cause. All data were managed and housed on a central server at the Medical University of South Carolina. A data query system and periodic monitoring are in place to manage data integrity. In addition, ALFSG leadership conducted annual visits to clinical sites to verify data and ensure compliance with study procedures. Statistical Analysis Statistical analyses were performed using SAS, version 9.4 (SAS Institute). Missing values were not replaced or estimated. Patients with missing data were excluded from the respective analyses for those variables, and patients who were lost to follow-up before 21 days were excluded from the study. Descriptive statistics were used to characterize the demographic and other clinical variables. Categorical variables were compared using the chi-square test or the Fisher exact test (the latter when expected cell counts were <5). Medians were reported with interquartile ranges (IQRs) and were compared with the Wilcoxon rank-sum test. Survival and transplant outcomes at 21 days after study enrollment were classified as TFS (survival without liver transplantation), liver transplantation, or death (2). Outcomes were also determined at 1 and 2 years after study enrollment, but these data were less complete than the 21-day outcome data. Survival rates over time were assessed descriptively at the individual-site level to verify that changes in TFS were not affected by varying accrual of patients from different sites. Treatment utilization and survival and transplant outcomes were analyzed over time annually for trends and were also stratified into two 8-year periods: early (1998 to 2005) and later (2006 to 2013). Trends over time were analyzed using the CochranArmitage test. A significance level of less than 0.05 was used for all comparisons. Role of the Funding Source This study was funded by the National Institutes of Health. The funding source had no direct role in the design, conduct, or reporting of the study. Results Demographic Characteristics and Comorbidities During the 16-year study, 2070 patients (median age, 39.0 years [IQR, 29.0 to 52.0 years]) were enrolled in the ALFSG registry. Over the same interval, there were 660 confirmed ALF screen failures (286 due to failure to meet inclusion criteria, 212 for whom consent could not be obtained, and 162 for other reasons). Among enrolled patients, 69.3% were women and 76.4% were white (Table 1). Patients did not differ in sex, race, or ethnicity between the two 8-year periods but were significantly older and heavier in the later period. Prevalence of hypertension, heart disease, diabetes, psychiatric illness, and substance dependency all increased significantly between the early and later periods, whereas prevalence of renal disease did not. Table 1. Demographic Characteristics, Comorbidities, Clinical Severity, and Causes at Admission Causes and Clinical Severity of ALF The percentage of enrollment as a reflection of the most common causes of ALF did not change during the two 8-year periods. Hepatotoxicity due to APAP accounted for almost half the cases of ALF for the entire 16-year period (Table 1), with the highest annual prevalence (53.0%) occurring in 2013. Unintentional APAP overdoses (those in which patients took excessive medication over several days for such ailments as pain, malaise, or fever [10, 11]) were more common than intentional (suicidal) overdoses. Hepatitis A virus infection was significantly less evident during the later period (9 cases [0.8%]) than the early period (28 cases [2.8%]) (P< 0.001). Hepatic ischemia and autoimmune hepatitis increased modestly, whereas hepatitis B virus infection, drug-induced liver injury, Wilson disease, and BuddChiari syndrome were less frequently noted. Patients entered either the primary or the referral (study) site more rapidly after initial symptom onset in the later period (2.0 days [IQR, 0.0 to 8.0 days]) than the early period (3.0 days [IQR, 1.0 to 14.0 days]) (P< 0.001) (Table 1). However, the corresponding interval between symptom onset and HE onset was 4.0 days in both the early (IQR, 1.0 to 15.0 days) and later (IQR, 1.0 to 12.0 days) periods, and time from onset of jaundice to enrollment also was unchanged (3.0 days in each period [IQRs, 1.0 to 12.0 and 1.0 to 10.0 days, respectively]). Most patients with ALF were severely ill at study enrollment, with nearly 50% having grade 3 or 4 (that is, deep) HE throughout. Biochemical liver test results varied widely but indicated severe illness in most patients (Appendix Table 1). Appendix Table 1. Laboratory Values at Study Enrollment Laboratory Tests fo

Thalidomide-induced severe hepatotoxicity.

Thalidomide is a relatively safe and efficacious form of therapy in the treatment of advanced, refractory multiple myeloma. Hepatotoxicity is listed as an extremely rare adverse effect associated with its use. We describe a 76‐year‐old woman with multiple myeloma who was treated with dexamethasone and thalidomide. By week 6 of therapy, she had developed acute increases in her aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels to more than 50 times the upper limit of normal. Her liver function test results had been within the normal ranges before and immediately after the start of therapy, and the patient had no known history of underlying liver disease. A liver biopsy specimen demonstrated evidence of acute injury with chronic changes of underlying steatosis and bridging fibrosis due to previously undiagnosed nonalcoholic steatohepatitis. Immediately after discontinuing thalidomide, her liver function test results began trending downward. Seven days later, her AST and ALT levels had improved to 86 and 165 U/L, respectively. This case and a limited number of other reports demonstrate severe hepatotoxicity as a rare but potentially serious adverse effect of thalidomide therapy. With the expanding use of thalidomide as a therapeutic agent, clinicians must recognize severe hepatotoxicity as a potential complication. Whether patients with preexisting liver disease are at increased risk when receiving thalidomide remains to be seen.

Safety, tolerability, and pharmacokinetics of l-ornithine phenylacetate in patients with acute liver injury/failure and hyperammonemia

Cerebral edema remains a significant cause of morbidity and mortality in patients with acute liver failure (ALF) and has been linked to elevated blood ammonia levels. l‐ornithine phenylacetate (OPA) may decrease ammonia by promoting its renal excretion as phenylacetylglutamine (PAGN), decreasing the risk of cerebral edema. We evaluated the safety, tolerability, and pharmacokinetics of OPA in patients with ALF and acute liver injury (ALI), including those with renal failure. Forty‐seven patients with ALI/ALF and ammonia ≥60 μM were enrolled. Patients received OPA in a dose escalation scheme from 3.3 g every 24 hours to 10 g every 24 hours; 15 patients received 20 g every 24 hours throughout the infusion for up to 120 hours. Plasma phenylacetate (PA) concentrations were uniformly below target (<75 μg/mL) in those receiving 3.3 g every 24 hours (median [interquartile range] 5.0 [5.0] μg/mL), and increased to target levels in all but one who received 20 g every 24 hours (150 [100] μg/mL). Plasma [PAGN] increased, and conversion of PA to PAGN became saturated, with increasing OPA dose. Urinary PAGN clearance and creatinine clearance were linearly related (r = 0.831, P < 0.0001). Mean ammonia concentrations based on the area under the curve decreased to a greater extent in patients who received 20 g of OPA every 24 hours compared with those who received the maximal dose of 3.3 or 6.7 g every 24 hours (P = 0.046 and 0.022, respectively). Of the reported serious adverse events (AEs), which included 11 deaths, none was attributable to study medication. The only nonserious AEs possibly related to study drug were headache and nausea/vomiting. Conclusion: OPA was well‐tolerated in patients with ALI/ALF, and no safety signals were identified. Target [PA] was achieved at infusion rates of 20 g every 24 hours, leading to ammonia excretion in urine as PAGN in proportion to renal function. Randomized, controlled studies of high‐dose OPA are needed to determine its use as an ammonia‐scavenging agent in patients with ALF. (Hepatology 2018;67:1003–1013)

HBV-Associated Acute Liver Failure After Immunosuppression and Risk of Death

BACKGROUND & AIMS: Acute liver failure (ALF) caused by hepatitis B virus (HBV) infection can occur after immunosuppressive treatment and be fatal, although it might be preventable. We aimed to characterize the causes, clinical course, and short‐term outcomes of HBV‐associated ALF after immune‐suppressive therapy, compared with patients with HBV‐associated ALF without immunosuppression (control subjects). METHODS: We performed a retrospective multicenter study of 156 consecutive patients diagnosed with HBV‐associated ALF (22 with a solid or blood malignancy) enrolled in the Acute Liver Failure Study Group registry from January 1998 through April 2015. We collected data on results of serologic and hepatic biochemistry analyses, grade of hepatic encephalopathy, Model for End‐Stage Liver Disease score, and Kings College criteria. We also collected data on clinical features, medical therapies, and complications in the first 7 days following study enrollment. Logistic regression was used to identify factors associated with transplant‐free survival at 21 days in HBV‐associated ALF (the primary outcome). RESULTS: Among patients with HBV‐associated ALF, 28 cases (18%) occurred after immunosuppressive therapy (15 patients received systemic corticosteroids and 21 received chemotherapy); and 128 cases did not (control subjects, 82%). Significantly greater proportions of patients with HBV‐associated ALF after immunosuppression were nonwhite persons, and had anemia or thrombocytopenia than controls (P < .02 for all). The serologic profile of HBV infection, severity of liver failure (based on MELD score), and complications (hepatic encephalopathy or need for mechanical ventilation, vasopressors, or renal replacement therapy) were similar between the groups (P > .17 for all). Factors associated with 21 day transplant‐free survival were increased MELD score (odds ratio ˜OR, 0.894 (95% confidence interval 0.842‐0.949 per increment), requirement for mechanical ventilation (OR 0.111(0.041‐0.300), and immunosuppressive therapy (OR 0.274(0.082‐0.923)). CONCLUSIONS: Within a cohort study of patients with HBV‐associated ALF, 18% had received immunosuppressive therapy. Significantly smaller proportions of patients with HBV‐associated ALF after immunosuppression survive beyond 21 days than patients with HBV‐associated ALF who did not receive immunosuppression. Patients undergoing chemotherapy should be screened for HBV infection and given appropriate antiviral therapies to reduce preventable mortality.

Outcomes in adults with acute liver failure between 1998 and 2013

Context Whether changes have occurred in the causes of acute liver failure (ALF), its management, or the survival of patients with the condition (with or without liver transplantation) is not known. Contribution This large cohort study found that despite similar causes and severity of ALF among patients referred to specialty centers from 1998 to 2013, the proportion of patients listed for liver transplantation decreased and survival improved among those who did not receive a transplant as well as those who did. Implication More study is warranted to better understand the specific changes in care that may have led to improved survival of patients with ALF. Acute liver failure (ALF) is defined as severe liver injury with rapid onset that results in hepatic encephalopathy (HE) and coagulopathy in persons without preexisting liver disease. The principal causes of ALF include acetaminophen (N-acetyl-p-aminophenol [APAP]) overdose, ischemic and pregnancy-associated liver injury, acute infection with hepatitis A or B virus, drug-induced liver injury, autoimmune hepatitis, BuddChiari syndrome, and Wilson disease (1, 2). For some causes, such as APAP toxicity, outcomes are favorable and transplant-free survival (TFS) approaches 70%, whereas other causes have unfavorable outcomes, including a much lower likelihood (<30%) of recovery without liver transplantation (2). One-year survival after emergency liver transplantation in patients with ALF in the United States and Europe is reportedly good but is lower than among patients with cirrhosis who receive a transplant (3). Patients with ALF often deteriorate rapidly and therefore receive the most urgent ranking (status 1) in the United Network for Organ Sharing transplantation system. Treatment of ALF in the intensive care unit is largely supportive and includes ventilator and vasopressor support for respiratory and/or circulatory failure, renal replacement therapy, plasma and blood transfusions, antibiotics, and measures to decrease intracranial pressure (46). N-acetylcysteine is used to treat APAP overdose and has shown efficacy in patients with ALF not due to APAP toxicity, particularly those referred early and having only mild HE (7). However, few disease-specific or general treatments are available that yield improved outcomes. In this study, our aim was to update the U.S. experience with ALF at specialized liver disease and transplant centers since the last published overview by the Acute Liver Failure Study Group (ALFSG) in 2002 (2). This group initiated its registry in January 1998 to better characterize the causes, clinical features, and outcomes of this super-orphan condition and aimed to enroll cases prospectively from participating liver transplant centers across North America. Accordingly, we analyzed data on all patients with ALF enrolled between 1998 and 2013, focusing on whether clinical features or outcomes of the ALF syndrome have changed over time. In addition, we sought to determine the relationship between ALF causes and rates of TFS and whether utilization of liver transplantation changed in the 16-year observation period. Methods Study Population From 1 January 1998 through 31 December 2013, adult patients were consecutively enrolled in the ALFSG registry (2) from 31 U.S. academic liver centers (of which only 5 legacy sites participated continuously throughout the 16-year period). All enrolled patients had both coagulopathy (international normalized ratio [INR] 1.5) and any grade of HE (as clinically defined by the classic West Haven criteria [8]) within 26 weeks of the first symptoms and had no evidence of significant chronic liver disease, especially cirrhosis. Patients for whom prior liver transplantation failed (due to primary graft nonfunction or other causes) were excluded. During the 16-year period, the number of sites participating, their geographic locations, and the number of cases contributed per site varied depending on each sites ability to continually identify and enroll patients over time (Appendix Figure 1). Appendix Figure 1. Site enrollment over time. Patients were usually admitted to intensive care units; 82.4% were hospitalized before transfer to the referral tertiary care study site, and the remainder were admitted directly to the study site. All were screened for inclusion according to the ALF criteria defined earlier. Written informed consent was obtained from the legal next of kin. A log of screen failures and consent refusal was maintained. All centers complied with local institutional review board requirements. Data Management and Integrity At enrollment into the study, we prospectively collected patient demographic characteristics (age, sex, race, and ethnicity); a complete medical history, including the timing of the first symptom of ill health, onset of jaundice and HE, and the number of days between the first symptom, hospital admission, transfer to the study site (where relevant), and enrollment in the study; and clinical features, including blood pressure and need for vasopressor support, mechanical ventilation, and renal replacement therapy, which allowed calculation of the systemic inflammatory response syndrome (SIRS) score (9). We also collected standard liver and metabolic test results and clinical data daily for up to 7 days, as well as serologic and other tests to determine the cause. All data were managed and housed on a central server at the Medical University of South Carolina. A data query system and periodic monitoring are in place to manage data integrity. In addition, ALFSG leadership conducted annual visits to clinical sites to verify data and ensure compliance with study procedures. Statistical Analysis Statistical analyses were performed using SAS, version 9.4 (SAS Institute). Missing values were not replaced or estimated. Patients with missing data were excluded from the respective analyses for those variables, and patients who were lost to follow-up before 21 days were excluded from the study. Descriptive statistics were used to characterize the demographic and other clinical variables. Categorical variables were compared using the chi-square test or the Fisher exact test (the latter when expected cell counts were <5). Medians were reported with interquartile ranges (IQRs) and were compared with the Wilcoxon rank-sum test. Survival and transplant outcomes at 21 days after study enrollment were classified as TFS (survival without liver transplantation), liver transplantation, or death (2). Outcomes were also determined at 1 and 2 years after study enrollment, but these data were less complete than the 21-day outcome data. Survival rates over time were assessed descriptively at the individual-site level to verify that changes in TFS were not affected by varying accrual of patients from different sites. Treatment utilization and survival and transplant outcomes were analyzed over time annually for trends and were also stratified into two 8-year periods: early (1998 to 2005) and later (2006 to 2013). Trends over time were analyzed using the CochranArmitage test. A significance level of less than 0.05 was used for all comparisons. Role of the Funding Source This study was funded by the National Institutes of Health. The funding source had no direct role in the design, conduct, or reporting of the study. Results Demographic Characteristics and Comorbidities During the 16-year study, 2070 patients (median age, 39.0 years [IQR, 29.0 to 52.0 years]) were enrolled in the ALFSG registry. Over the same interval, there were 660 confirmed ALF screen failures (286 due to failure to meet inclusion criteria, 212 for whom consent could not be obtained, and 162 for other reasons). Among enrolled patients, 69.3% were women and 76.4% were white (Table 1). Patients did not differ in sex, race, or ethnicity between the two 8-year periods but were significantly older and heavier in the later period. Prevalence of hypertension, heart disease, diabetes, psychiatric illness, and substance dependency all increased significantly between the early and later periods, whereas prevalence of renal disease did not. Table 1. Demographic Characteristics, Comorbidities, Clinical Severity, and Causes at Admission Causes and Clinical Severity of ALF The percentage of enrollment as a reflection of the most common causes of ALF did not change during the two 8-year periods. Hepatotoxicity due to APAP accounted for almost half the cases of ALF for the entire 16-year period (Table 1), with the highest annual prevalence (53.0%) occurring in 2013. Unintentional APAP overdoses (those in which patients took excessive medication over several days for such ailments as pain, malaise, or fever [10, 11]) were more common than intentional (suicidal) overdoses. Hepatitis A virus infection was significantly less evident during the later period (9 cases [0.8%]) than the early period (28 cases [2.8%]) (P< 0.001). Hepatic ischemia and autoimmune hepatitis increased modestly, whereas hepatitis B virus infection, drug-induced liver injury, Wilson disease, and BuddChiari syndrome were less frequently noted. Patients entered either the primary or the referral (study) site more rapidly after initial symptom onset in the later period (2.0 days [IQR, 0.0 to 8.0 days]) than the early period (3.0 days [IQR, 1.0 to 14.0 days]) (P< 0.001) (Table 1). However, the corresponding interval between symptom onset and HE onset was 4.0 days in both the early (IQR, 1.0 to 15.0 days) and later (IQR, 1.0 to 12.0 days) periods, and time from onset of jaundice to enrollment also was unchanged (3.0 days in each period [IQRs, 1.0 to 12.0 and 1.0 to 10.0 days, respectively]). Most patients with ALF were severely ill at study enrollment, with nearly 50% having grade 3 or 4 (that is, deep) HE throughout. Biochemical liver test results varied widely but indicated severe illness in most patients (Appendix Table 1). Appendix Table 1. Laboratory Values at Study Enrollment Laboratory Tests fo

Outcomes in Adults With Acute Liver Failure Between 1998 and 2013An Observational Cohort StudyOutcomes in Adults With Acute Liver Failure Between 1998 and 2013

Context Whether changes have occurred in the causes of acute liver failure (ALF), its management, or the survival of patients with the condition (with or without liver transplantation) is not known. Contribution This large cohort study found that despite similar causes and severity of ALF among patients referred to specialty centers from 1998 to 2013, the proportion of patients listed for liver transplantation decreased and survival improved among those who did not receive a transplant as well as those who did. Implication More study is warranted to better understand the specific changes in care that may have led to improved survival of patients with ALF. Acute liver failure (ALF) is defined as severe liver injury with rapid onset that results in hepatic encephalopathy (HE) and coagulopathy in persons without preexisting liver disease. The principal causes of ALF include acetaminophen (N-acetyl-p-aminophenol [APAP]) overdose, ischemic and pregnancy-associated liver injury, acute infection with hepatitis A or B virus, drug-induced liver injury, autoimmune hepatitis, BuddChiari syndrome, and Wilson disease (1, 2). For some causes, such as APAP toxicity, outcomes are favorable and transplant-free survival (TFS) approaches 70%, whereas other causes have unfavorable outcomes, including a much lower likelihood (<30%) of recovery without liver transplantation (2). One-year survival after emergency liver transplantation in patients with ALF in the United States and Europe is reportedly good but is lower than among patients with cirrhosis who receive a transplant (3). Patients with ALF often deteriorate rapidly and therefore receive the most urgent ranking (status 1) in the United Network for Organ Sharing transplantation system. Treatment of ALF in the intensive care unit is largely supportive and includes ventilator and vasopressor support for respiratory and/or circulatory failure, renal replacement therapy, plasma and blood transfusions, antibiotics, and measures to decrease intracranial pressure (46). N-acetylcysteine is used to treat APAP overdose and has shown efficacy in patients with ALF not due to APAP toxicity, particularly those referred early and having only mild HE (7). However, few disease-specific or general treatments are available that yield improved outcomes. In this study, our aim was to update the U.S. experience with ALF at specialized liver disease and transplant centers since the last published overview by the Acute Liver Failure Study Group (ALFSG) in 2002 (2). This group initiated its registry in January 1998 to better characterize the causes, clinical features, and outcomes of this super-orphan condition and aimed to enroll cases prospectively from participating liver transplant centers across North America. Accordingly, we analyzed data on all patients with ALF enrolled between 1998 and 2013, focusing on whether clinical features or outcomes of the ALF syndrome have changed over time. In addition, we sought to determine the relationship between ALF causes and rates of TFS and whether utilization of liver transplantation changed in the 16-year observation period. Methods Study Population From 1 January 1998 through 31 December 2013, adult patients were consecutively enrolled in the ALFSG registry (2) from 31 U.S. academic liver centers (of which only 5 legacy sites participated continuously throughout the 16-year period). All enrolled patients had both coagulopathy (international normalized ratio [INR] 1.5) and any grade of HE (as clinically defined by the classic West Haven criteria [8]) within 26 weeks of the first symptoms and had no evidence of significant chronic liver disease, especially cirrhosis. Patients for whom prior liver transplantation failed (due to primary graft nonfunction or other causes) were excluded. During the 16-year period, the number of sites participating, their geographic locations, and the number of cases contributed per site varied depending on each sites ability to continually identify and enroll patients over time (Appendix Figure 1). Appendix Figure 1. Site enrollment over time. Patients were usually admitted to intensive care units; 82.4% were hospitalized before transfer to the referral tertiary care study site, and the remainder were admitted directly to the study site. All were screened for inclusion according to the ALF criteria defined earlier. Written informed consent was obtained from the legal next of kin. A log of screen failures and consent refusal was maintained. All centers complied with local institutional review board requirements. Data Management and Integrity At enrollment into the study, we prospectively collected patient demographic characteristics (age, sex, race, and ethnicity); a complete medical history, including the timing of the first symptom of ill health, onset of jaundice and HE, and the number of days between the first symptom, hospital admission, transfer to the study site (where relevant), and enrollment in the study; and clinical features, including blood pressure and need for vasopressor support, mechanical ventilation, and renal replacement therapy, which allowed calculation of the systemic inflammatory response syndrome (SIRS) score (9). We also collected standard liver and metabolic test results and clinical data daily for up to 7 days, as well as serologic and other tests to determine the cause. All data were managed and housed on a central server at the Medical University of South Carolina. A data query system and periodic monitoring are in place to manage data integrity. In addition, ALFSG leadership conducted annual visits to clinical sites to verify data and ensure compliance with study procedures. Statistical Analysis Statistical analyses were performed using SAS, version 9.4 (SAS Institute). Missing values were not replaced or estimated. Patients with missing data were excluded from the respective analyses for those variables, and patients who were lost to follow-up before 21 days were excluded from the study. Descriptive statistics were used to characterize the demographic and other clinical variables. Categorical variables were compared using the chi-square test or the Fisher exact test (the latter when expected cell counts were <5). Medians were reported with interquartile ranges (IQRs) and were compared with the Wilcoxon rank-sum test. Survival and transplant outcomes at 21 days after study enrollment were classified as TFS (survival without liver transplantation), liver transplantation, or death (2). Outcomes were also determined at 1 and 2 years after study enrollment, but these data were less complete than the 21-day outcome data. Survival rates over time were assessed descriptively at the individual-site level to verify that changes in TFS were not affected by varying accrual of patients from different sites. Treatment utilization and survival and transplant outcomes were analyzed over time annually for trends and were also stratified into two 8-year periods: early (1998 to 2005) and later (2006 to 2013). Trends over time were analyzed using the CochranArmitage test. A significance level of less than 0.05 was used for all comparisons. Role of the Funding Source This study was funded by the National Institutes of Health. The funding source had no direct role in the design, conduct, or reporting of the study. Results Demographic Characteristics and Comorbidities During the 16-year study, 2070 patients (median age, 39.0 years [IQR, 29.0 to 52.0 years]) were enrolled in the ALFSG registry. Over the same interval, there were 660 confirmed ALF screen failures (286 due to failure to meet inclusion criteria, 212 for whom consent could not be obtained, and 162 for other reasons). Among enrolled patients, 69.3% were women and 76.4% were white (Table 1). Patients did not differ in sex, race, or ethnicity between the two 8-year periods but were significantly older and heavier in the later period. Prevalence of hypertension, heart disease, diabetes, psychiatric illness, and substance dependency all increased significantly between the early and later periods, whereas prevalence of renal disease did not. Table 1. Demographic Characteristics, Comorbidities, Clinical Severity, and Causes at Admission Causes and Clinical Severity of ALF The percentage of enrollment as a reflection of the most common causes of ALF did not change during the two 8-year periods. Hepatotoxicity due to APAP accounted for almost half the cases of ALF for the entire 16-year period (Table 1), with the highest annual prevalence (53.0%) occurring in 2013. Unintentional APAP overdoses (those in which patients took excessive medication over several days for such ailments as pain, malaise, or fever [10, 11]) were more common than intentional (suicidal) overdoses. Hepatitis A virus infection was significantly less evident during the later period (9 cases [0.8%]) than the early period (28 cases [2.8%]) (P< 0.001). Hepatic ischemia and autoimmune hepatitis increased modestly, whereas hepatitis B virus infection, drug-induced liver injury, Wilson disease, and BuddChiari syndrome were less frequently noted. Patients entered either the primary or the referral (study) site more rapidly after initial symptom onset in the later period (2.0 days [IQR, 0.0 to 8.0 days]) than the early period (3.0 days [IQR, 1.0 to 14.0 days]) (P< 0.001) (Table 1). However, the corresponding interval between symptom onset and HE onset was 4.0 days in both the early (IQR, 1.0 to 15.0 days) and later (IQR, 1.0 to 12.0 days) periods, and time from onset of jaundice to enrollment also was unchanged (3.0 days in each period [IQRs, 1.0 to 12.0 and 1.0 to 10.0 days, respectively]). Most patients with ALF were severely ill at study enrollment, with nearly 50% having grade 3 or 4 (that is, deep) HE throughout. Biochemical liver test results varied widely but indicated severe illness in most patients (Appendix Table 1). Appendix Table 1. Laboratory Values at Study Enrollment Laboratory Tests fo