Association of Acetaminophen (Paracetamol) Use With Severity and Outcomes in Patients With Viral Hepatitis-Associated Acute Liver Failure.

INTRODUCTION: Acute viral hepatitis (AVH) comprises 11% of acute liver failure (ALF) in North America while acetaminophen (APAP) toxicity represents 46%. The use of APAP to treat prodromal hepatitis symptoms is common. It is unknown if concurrent APAP use impacts liver injury in AVH-induced ALF. METHODS: In this prospective, multicenter cohort study, 356 patients meeting criteria for AVH including hepatitis A, B, Epstein-Barr virus, and herpes simplex virus, all leading to ALF (hepatic encephalopathy after acute illness, international normalized ratio ≥1.5), or acute liver injury (acute liver injury, international normalized ratio >2.0, no hepatic encephalopathy) were reviewed for evidence of APAP use: APAP ingestion history or measurement of serum APAP level or APAP-CYS adducts, a specific biomarker released into blood with APAP injury. Patients were grouped by APAP exposure level, from high (measurable APAP levels or toxic APAP-CYS), medium (therapeutic APAP-CYS), low (history of APAP ingestion only and/or barely detectable APAP-CYS), or no exposure recorded. RESULTS: Two hundred five of 356 patients (57.5%) with AVH-ALF had evidence of APAP use: 87 out of 356 (24%) demonstrated high or medium exposures. The aminotransferase and bilirubin levels of high/medium group resembled a mixed APAP-viral injury. Mortality was the highest (51.6%, 21.4%, 28.8%, and 30.5%), and transplant-free survival was the lowest (22.6%, 44.6%, 41.5%, and 40.4%) in the high exposure group compared with medium, low, and no exposure groups. However, the specific comparisons of mortality and transplant-free survival between the high exposure and no exposure groups were not statistically different even after adjusting for baseline patient characteristics differences. DISCUSSION: APAP use in AVH-ALF is common and may negatively impact outcomes compared with little or no APAP exposure. Prospective studies of the safest and effective dose of APAP to use in patients with AVH are needed.

Increasing practice and acceptable outcomes of high-MELD living donor liver transplantation in the USA.

Recent deceased-donor allocation changes in the United States may have increased high-Model for End-Stage Liver Disease (MELD) living donor liver transplantation (LDLT); however, outcomes in these patients remain poorly defined. We aimed to examine the impact of the MELD score on LDLT outcomes. Using UNOS data (January 1, 2010-December 31, 2021), LDLT recipients were identified and stratified into low-MELD (<15), intermediate-MELD (15-24), and high-MELD (≥25) groups. We compared outcomes between MELD-stratified LDLT groups and between MELD-stratified LDLT and donation after brain death liver transplantation recipients. We used Kaplan-Meier analysis to compare graft survival rates and multivariable Cox proportional hazards modeling to identify factors associated with graft outcomes. Of 3558 LDLTs, 1605 (45.1%) were low-MELD, 1616 (45.4%) intermediate-MELD, and 337 (9.5%) high-MELD. Over the study period, the annual number of LDLTs increased from 282 to 569, and the proportion of high-MELD LDLTs increased from 3.9% to 7.7%. Graft survival was significantly higher in low-MELD versus high-MELD LDLT recipients (adjusted HR = 1.36, 95% CI: 1.03-1.79); however, 5-year survival exceeded 70.0% in both groups. We observed no significant difference in graft survival between high-MELD LDLT and high-MELD donation after brain death liver transplantation recipients (adjusted HR: 1.25, 95% CI:0.99-1.58), with a 5-year survival of 71.5% and 77.3%, respectively. Low LDLT center volume (<3 LDLTs/year) and recipient life support requirement were both associated with inferior graft outcomes among high-MELD LDLT recipients. While higher MELD scores confer graft failure risk in LDLT, high-MELD LDLT outcomes are acceptable with similar outcomes to MELD-stratified donation after brain death liver transplantation recipients. Future practice guidance should consider the expansion of LDLT recommendations to high-MELD recipients in centers with expertise to help reduce donor shortage.

The chemokine CXCL14 is a novel early prognostic biomarker for poor outcome in acetaminophen-induced acute liver failure.

BACKGROUND AND AIMS: Patients with acetaminophen-induced acute liver failure are more likely to die while on the liver transplant waiting list than those with other causes of acute liver failure. Therefore, there is an urgent need for prognostic biomarkers that can predict the need for liver transplantation early after an acetaminophen overdose. APPROACH AND RESULTS: We evaluated the prognostic potential of plasma chemokine C-X-C motif ligand 14 (CXCL14) concentrations in patients with acetaminophen (APAP) overdose (n=50) and found that CXCL14 is significantly higher in nonsurviving patients compared to survivors with acute liver failure ( p < 0.001). Logistic regression and AUROC analyses revealed that CXCL14 outperformed the MELD score, better discriminating between nonsurvivors and survivors. We validated these data in a separate cohort of samples obtained from the Acute Liver Failure Study Group (n = 80), where MELD and CXCL14 had similar AUC (0.778), but CXCL14 demonstrated higher specificity (81.2 vs. 52.6) and positive predictive value (82.4 vs. 65.4) for death or need for liver transplantation. Next, combining the patient cohorts and using a machine learning training/testing scheme to mimic the clinical scenario, we found that CXCL14 outperformed MELD based on AUC (0.821 vs. 0.787); however, combining MELD and CXCL14 yielded the best AUC (0.860). CONCLUSIONS: We find in 2 independent cohorts of acetaminophen overdose patients that circulating CXCL14 concentration is a novel early prognostic biomarker for poor outcomes, which may aid in guiding decisions regarding patient management. Moreover, our findings reveal that CXCL14 performs best when measured soon after patient presentation to the clinic, highlighting its importance for early warning of poor prognosis.

Future directions in acute liver failure.

Acute liver failure (ALF) describes a clinical syndrome of rapid hepatocyte injury leading to liver failure manifested by coagulopathy and encephalopathy in the absence of pre-existing cirrhosis. The hallmark diagnostic features are a prolonged prothrombin time (ie, an international normalized ratio of prothrombin time of ≥1.5) and any degree of mental status alteration (HE). As a rare, orphan disease, it seemed an obvious target for a multicenter network. The Acute Liver Failure Study Group (ALFSG) began in 1997 to more thoroughly study and understand the causes, natural history, and management of ALF. Over the course of 22 years, 3364 adult patients were enrolled in the study registry (2614 ALF and 857 acute liver injury-international normalized ratio 2.0 but no encephalopathy-ALI) and >150,000 biosamples collected, including serum, plasma, urine, DNA, and liver tissue. Within the Registry study sites, 4 prospective substudies were conducted and published, 2 interventional ( N -acetylcysteine and ornithine phenylacetate), 1 prognostic [ 13 C-methacetin breath test (MBT)], and 1 mechanistic (rotational thromboelastometry). To review ALFSG's accomplishments and consider next steps, a 2-day in-person conference was held at UT Southwestern Medical Center, Dallas, TX, entitled "Acute Liver Failure: Science and Practice," in May 2022. To summarize the important findings in the field, this review highlights the current state of understanding of ALF and, more importantly, asks what further studies are needed to improve our understanding of the pathogenesis, natural history, and management of this unique and dramatic condition.

Use of HBV RNA and to predict change in serological status and disease activity in CHB.

BACKGROUND AND AIMS: Predicting changes in disease activity and serological endpoints is necessary for the management of patients with chronic hepatitis B (CHB). We examined whether HBV RNA and hepatitis B core-related antigen (HBcrAg), two specialized virological markers proposed to reflect the activity of covalently closed circular DNA, may improve the ability to predict not sustained inactive carrier phase, spontaneous alanine aminotransferase (ALT) flare, HBeAg loss, and HBsAg loss. APPROACH AND RESULTS: Among eligible participants enrolled in the North American Hepatitis B Research Network Adult Cohort Study, we evaluated demographic, clinical, and virologic characteristics, including HBV RNA and HBcrAg, to predict not sustained inactive carrier phase, ALT flare, HBeAg loss, and HBsAg loss through a series of Cox proportional hazard or logistic regression models, controlling for antiviral therapy use. Among the study population, 54/103 participants experienced not sustained inactive carrier phase, 41/1006 had a spontaneous ALT flare, 83/250 lost HBeAg, and 54/1127 lost HBsAg. HBV RNA or HBcrAg were predictive of all 4 events. However, their addition to models of the readily available host (age, sex, race/ethnicity), clinical (ALT, use of antiviral therapy), and viral factors (HBV DNA), which had acceptable-excellent accuracy (e.g., AUC = 0.72 for ALT flare, 0.92 for HBeAg loss, and 0.91 for HBsAg loss), provided only small improvements in predictive ability. CONCLUSION: Given the high predictive ability of readily available markers, HBcrAg and HBV RNA have a limited role in improving the prediction of key serologic and clinical events in patients with CHB.

Ammonia and urea metabolism in acute liver failure: A multicentre cohort study.

BACKGROUND & AIMS: Ammonia is metabolized into urea in the liver. In acute liver failure (ALF), ammonia has been associated with survival. However, urea variation has been poorly studied. METHODS: Observational cohort including ALF patients from Curry Cabral Hospital (Lisbon, Portugal) and Clinic Hospital (Barcelona, Spain) between 10/2010 and 01/2023. The United States ALF Study Group cohort was used for external validation. Primary exposures were serum ammonia and urea on ICU admission. Primary endpoint was 30-day transplant-free survival (TFS). Secondary endpoint was explanted liver weight. RESULTS: Among 191 ALF patients, median (IQR) age was 46 (32; 57) years and 85 (44.5%) were males. Overall, 86 (45.0%) patients were transplanted and 75 (39.3%) died. Among all ALF patients, following adjustment for age, sex, body weight, and aetiology, higher ammonia or lower urea was independently associated with higher INR on ICU admission (p < .009). Among all ALF patients, following adjustment for sex, aetiology, and lactate, higher ammonia was independently associated with lower TFS (adjusted odds ratio (95% confidence interval [CI]) = 0.991 (0.985; 0.997); p = .004). This model predicted TFS with good discrimination (area under receiver operating curve [95% CI] = 0.78 [0.75; 0.82]) and reasonable calibration (R2 of 0.43 and Brier score of 0.20) after external validation. Among transplanted patients, following adjustment for age, sex, actual body weight, and aetiology, higher ammonia (p = .024) or lower (p < .001) urea was independently associated with lower explanted liver weight. CONCLUSIONS: Among ALF patients, serum ammonia and urea were associated with ALF severity. A score incorporating serum ammonia predicted TFS reasonably well.

Macrophage activation markers are associated with infection and mortality in patients with acute liver failure.

BACKGROUND AND AIMS: Acute liver failure is a multisystem disorder with a high mortality and frequent need for emergency liver transplantation. Following massive innate immune system activation, soluble markers of macrophage activation are released during liver damage and their association with disease severity and prognosis requires exploration. METHODS: Patients ALF from the United States Acute Liver Failure Study Group (USALFSG, n = 224) and King's College Hospital (n = 40) together with healthy controls (HC, n = 50) were recruited. Serum from early (Days 1-3) and late (>Day 3) time points were analysed for MAMs by enzyme-linked immunosorbent assay correlated to markers of illness severity and 21-day spontaneous survival. Surface expression phenotyping was performed via Flow Cytometry on CD14+ monocytes. RESULTS: All MAMs serum concentrations were significantly higher in ALF compared to controls (p < .0001). sCD206 concentration was higher in early and late stages of the disease in patients with bacteraemia (p = .002) and infection in general (p = .006). In MELD-adjusted multivariate modelling, sCD206 and sCD163 were independently associated with mortality. CD14+ monocyte expression of CD206 (p < .001) was higher in patients with ALF compared with controls and correlated with SOFA score (p = .018). sCD206 was independently validated as a predictor of infection in an external cohort. CONCLUSIONS: sCD206 is increased in serum of ALF patients with infections and poor outcome and is upregulated on CD14+ monocytes. Later measurements of sCD163 and sCD206 during the evolution of ALF have potential as mechanistic predictors of mortality. sCD206 should be explored as a biomarker of sepsis and mortality in ALF.

Early Graft Failure After Living-Donor Liver Transplant.

BACKGROUND: Living-donor liver transplantation (LDLT) has been increasing in the USA. While data exist on longer-term patient and graft outcomes, a contemporary analysis of short-term outcomes is needed. AIM: Evaluate short-term (30-day) graft failure rates and identify predictors associated with these outcomes. METHODS: Adult (≥ 18) LDLT recipients from 01/2004 to 12/2021 were analyzed from the United States Scientific Registry of Transplant Recipients. Graft status at 30 days was assessed with graft failure defined as retransplantation or death. Comparison of continuous and categorical variables was performed and a multivariable logistic regression was used to identify risk factors of early graft failure. RESULTS: During the study period, 4544 LDLTs were performed with a graft failure rate of 3.4% (155) at 30 days. Grafts from male donors (aOR: 0.63, CI 0.44-0.89), right lobe grafts (aOR: 0.40, CI 0.27-0.61), recipients aged > 60 years (aOR: 0.52, CI 0.32-0.86), and higher recipient albumin (aOR: 0.73, CI 0.57-0.93) were associated with superior early graft outcomes, whereas Asian recipient race (vs. White; aOR: 3.75, CI 1.98-7.10) and a history of recipient PVT (aOR: 2.7, CI 1.52-4.78) were associated with inferior outcomes. LDLTs performed during the most recent 2016-2021 period (compared to 2004-2009 and 2010-2015) resulted in significantly superior outcomes (aOR: 0.45, p < 0.001). CONCLUSION: Our study demonstrates that while short-term adult LDLT graft failure is uncommon, there are opportunities for optimizing outcomes by prioritizing right lobe donation, improving candidate nutritional status, and careful pre-transplant risk assessment of candidates with known PVT. Notably, a period effect exists whereby increased LDLT experience in the most recent era correlated with improved outcomes.

Differentiating Ischemic Hepatitis from Acetaminophen Overdose in Acute Liver Failure: Role of Acetaminophen Adducts-Ischemic Hepatitis vs Acetaminophen Overdose.

BACKGROUND AND AIMS: Acetaminophen (APAP) hepatotoxicity and ischemic hepatic injury (IH) demonstrate remarkably similar biochemical patterns. Deciding between these two etiologies in the setting of acute liver failure (ALF) can be challenging. We reviewed all cases in the Acute Liver Failure Study Group (ALFSG) registry where these diagnoses were considered, to determine reasons for, and frequency of, difficulties making these diagnoses. We hypothesized that the newly developed APAP-CYS adduct assay could help in discerning the correct diagnosis. METHODS: Among 3364 patients with ALF or acute liver injury (ALI: INR ≥ 2.0 but without encephalopathy) between 1998 and 2019, 1952 (58%) received a final diagnosis of either APAP (1681) or IH (271). We utilized a review committee of senior hepatologists as well as the APAP-CYS assay (where sera were available), measuring the presence of toxic by-products of APAP injury to optimize adjudication. RESULTS: With these methods, a total of 575 adduct positive APAP cases included 488 recognized APAP, as well as an additional 87 patients previously diagnosed as other etiologies. Nine cases initially attributed to IH were deemed combination APAP-IH injuries. Conversely, 215 of the 280 IH subjects tested for adducts disclosed 173 confirmed as IH with adduct testing below the toxicity threshold, while 9 cases were revised from APAP to the IH-APAP combination phenotype, where both hypotension and APAP likely played a role. CONCLUSIONS: Discerning APAP from IH can be difficult-in rare cases, combined injury is observed (18/1952). APAP-CYS testing resulted in revising the diagnosis in 14.6% of cases.

Acute Hepatitis B Virus Infection in North American Adults.

BACKGROUND & AIMS: Acute hepatitis B virus (aHBV) is thought to be self-limited with clearance of hepatitis B surface antigen (HBsAg) within 6 months. There are limited reports of the presenting features and outcomes of adults with symptomatic aHBV in the United States. METHODS: Demographics, clinical features, and 12-month outcomes of patients with adjudicated aHBV were captured prospectively and compared with a contemporaneous cohort of chronic HBV (cHBV) patients enrolled in the Hepatitis B Research Network. RESULTS: Between 2011 and 2018, 60 adjudicated patients with aHBV were compared with 1534 cHBV untreated controls. Although similar in age, other features were dissimilar: aHBV patients were more often male (72% vs 51%), single (72% vs 30%), and non-Hispanic whites or blacks (75% vs 24%). They also were frequently genotype A2 (65% vs 9%), having different risk factors: sexual exposure (75% vs 16%) or injection drug use (10% vs 2%), compared with the cHBV controls. In addition to higher serum aminotransferase and bilirubin levels, acute patients had higher HBV DNA levels (4.8 vs 3.6 log10 IU/mL), whereas quantitative hepatitis B e antigen (HBeAg) levels were lower (1.4 vs 3.0 log10 IU/mL), despite higher rates of HBeAg (73% vs 25%). The median time to HBsAg clearance was 27 weeks and to anti-HBs appearance, 41 weeks. CONCLUSIONS: In the current era, caucasian men infected with genotype A2 as a result of sexual exposure or injection drug use were the predominant group in aHBV, suggesting a potential strategy for adult vaccination in North America. Strikingly, only an estimated 36% of subjects cleared HBsAg by month 6; the definition of resolution in acute hepatitis B may need to be modified. ClinicalTirals.gov number NCT01263587.

The Role of Carbamoyl Phosphate Synthetase 1 as a Prognostic Biomarker in Patients With Acetaminophen-induced Acute Liver Failure.

BACKGROUND & AIMS: Carbamoyl phosphate synthetase 1 (CPS1) is a highly abundant mitochondrial urea cycle enzyme that is expressed primarily in hepatocytes. CPS1 is constitutively and physiologically secreted into bile but is released into the bloodstream upon acute liver injury (ALI). Given its abundance and known short half-life, we tested the hypothesis that it may serve as a prognostic serum biomarker in the setting of acute liver failure (ALF). METHODS: CPS1 levels were determined using enzyme-linked immunosorbent assay and immunoblotting of sera collected by the ALF Study Group (ALFSG) from patients with ALI and ALF (103 patients with acetaminophen and 167 non-acetaminophen ALF etiologies). A total of 764 serum samples were examined. The inclusion of CPS1 was compared with the original ALFSG Prognostic Index by area under the receiver operating characteristic curve analysis. RESULTS: CPS1 values for acetaminophen-related patients were significantly higher than for non-acetaminophen patients (P < .0001). Acetaminophen-related patients who received a liver transplant or died within 21 days of hospitalization exhibited higher CPS1 levels than patients who spontaneously survived (P = .01). Logistic regression and area under the receiver operating characteristic analysis of CPS1 enzyme-linked immunosorbent assay values improved the accuracy of the ALFSG Prognostic Index, which performed better than the Model for End-Stage Liver Disease, in predicting 21-day transplant-free survival for acetaminophen- but not non-acetaminophen-related ALF. An increase of CPS1 but not alanine transaminase or aspartate transaminase, when comparing day 3 with day 1 levels was found in a higher percentage of acetaminophen transplanted/dead patients (P < .05). CONCLUSION: Serum CPS1 determination provides a new potential prognostic biomarker to assess patients with acetaminophen-induced ALF.

Outcomes of patients with acute liver failure listed for liver transplantation: A multicenter prospective cohort analysis.

Liver transplantation (LT) is a life-saving treatment for patients with acute liver failure (ALF). Currently, there are few detailed data regarding long-term outcomes after LT for ALF. We combined prospective data from the Acute Liver Failure Study Group (ALFSG) Registry with those of the Scientific Registry of Transplant Recipients (SRTR) to assess outcomes among consecutive patients with ALF listed for LT. Cohort analysis of detailed pretransplantation data for patients listed for LT for ALF in the ALFSG Registry between January 1998 and October 2018 matched with transplantation-related data from the SRTR. Primary outcomes were 1- and 3-year post-LT patient survival. Secondary outcome was receipt of LT; independent associations with successful receipt of LT were determined using multivariable logistic regression. Of 624 patients with ALF listed for LT, 398 (64%) underwent LT, 100 (16%) died without LT, and 126 (20%) recovered spontaneously. Among LT recipients, etiologies included seronegative/indeterminate (22%), drug-induced liver injury (18%), acetaminophen overdose (APAP; 16%), and viral hepatitis (15%). The 1- and 3-year post-LT patient survival rates were 91% and 90%, respectively. Comparing those dying on the waiting list versus with those who received LT, the former had more severe multiorgan failure, reflected by increased vasopressor use (65% vs. 22%), mechanical ventilation (84% vs. 57%), and renal replacement therapy (57% vs. 30%; p < 0.0001 for all). After adjusting for relevant covariates, age (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.00-1.04), APAP etiology (aOR 2.72, 95% CI 1.42-5.23), requirement for vasopressors (aOR 4.19, 95% CI 2.44-7.20), Grade III/IV hepatic encephalopathy (aOR 2.47, 95% CI 1.29-4.72), and Model for End-Stage Liver Disease (MELD) scores (aOR 1.05, 95% CI 1.02-1.09; p < 0.05 for all) were independently associated with death without receipt of LT. Post-LT outcomes for ALF are excellent in this cohort of very ill patients. The development of multiorgan failure while on the transplantation list and APAP ALF etiology were associated with a lower likelihood of successful receipt of LT.

Generation of neutrophil extracellular traps in patients with acute liver failure is associated with poor outcome.

BACKGROUND AND AIMS: Acute liver failure (ALF) is characterized by significant changes in the hemostatic system and by systemic inflammation. The formation of neutrophil extracellular traps (NETs), in which an activated neutrophil expels its DNA, histones, and granular enzymes, such as myeloperoxidase (MPO), has been associated with immune-mediated and thrombotic diseases. We hypothesized that formation of NETs in patients with ALF contributes to progression of disease. APPROACH AND RESULTS: A total of 676 patients with ALF (international normalized ratio [INR], ≥1.5) or severe acute liver injury (ALI; INR, ≥2.0) were recruited from the U.S. ALF Study Group Registry between 2011 and 2018, of whom 308 patients (45.6%) had acetaminophen-induced ALF. Up to 21 days after admission, 483 patients (71.5%) survived without liver transplantation (LT). Levels of cell-free DNA (cfDNA) and the specific NET marker MPO-DNA complexes were measured in plasma samples obtained on admission and compared to levels in healthy controls. In addition, liver tissue obtained at transplantation of 20 ALF patients was stained for NETs. Levels of cfDNA were 7.1-fold, and MPO-DNA complexes 2.5-fold, higher in patients with ALF compared to healthy controls. cfDNA levels were not associated with 21-day transplant-free survival, but were higher in those patients with more-severe disease on admission, as reflected by various laboratory and clinical parameters. MPO-DNA levels were 30% higher in patients with ALF who died or required urgent LT. Liver tissue of ALF patients stained positive for NETs in 12 of 18 evaluable patients. CONCLUSIONS: Here, we provide evidence for NET formation in patients with ALF. Elevated plasma levels of MPO-DNA complexes in patients with ALF were associated with poor outcome, which suggests that NET formation contributes to disease progression.

Biliary atresia and liver transplantation in the United States: A contemporary analysis.

BACKGROUND: Biliary atresia (BA) remains the number one indication for paediatric liver transplantation (LT) worldwide but is an uncommon indication for older LT recipients. The impact of recent donor allocation changes, pervasive organ shortage and evolving LT practices on the BA LT population is unknown. METHODS: We identified patients who underwent LT between January 2010 and December 2021 using the UNOS database. We compared clinical outcomes between patients with BA and those with non-BA cholestatic liver disease. Groups were stratified by age, <12 years (allocated via PELD system) and ≥12 years (allocated via MELD system). Waitlist outcomes were compared using competing-risk regression analysis, graft survival rates were compared using Kaplan-Meier time-to-event analysis and Cox proportional hazards modelling provided adjusted estimates. RESULTS: There were 2754 BA LT waitlist additions and 2206 BA LTs (1937 <12 years [younger], 269 ≥12 years [older]). There were no differences in waitlist mortality between BA and non-BA cholestatic patients. Among BA LT recipients, there were 441 (20.0%) living-donor liver transplantations (LDLT) and 611 (27.7%) split deceased-donor LTs. Five-year graft survival was significantly higher among BA versus non-BA cholestatic patients in the older group (88.3% vs. 79.5%, p < .01) but not younger group (89.3% vs. 89.5%). Among BA LT recipients, improved graft outcomes were associated with LDLT (vs. split LT: HR: 2, 95% CI: 1.03-3.91) and higher transplant volume (volume >100 vs. <40 BA LTs: HR: 3.41, 95% CI: 1.87-6.2). CONCLUSION: Liver transplant outcomes among BA patients are excellent, with LDLT and higher transplant centre volume associated with optimal graft outcomes.

Indeterminate etiology of acute liver failure in North America: Less common, still grave prognosis.

BACKGROUND: The etiology of acute liver failure (ALF) remains one of the most important factors in determining prognosis and predicting outcomes. In a significant proportion of ALF cases, however, the etiology remains unknown and is categorized as indeterminate ALF (IND-ALF). In this study, we summarize findings from patients with IND-ALF from 32 transplant centers across the United States, and we compare laboratory, prognostic, and outcome data for patients with IND-ALF. METHODS: Between 1998 and 2019, 3364 adult patients with ALF or acute liver injury (ALI) from 32 liver transplant centers were enrolled in the ALFSG registry. The primary clinical outcome of interest was 21-day transplant-free survival (TFS). RESULTS: Of the 3364 patients enrolled in the ALFSG registry, 3.4 % (n = 114) were adjudicated as true indeterminate. On multivariate analysis, patients with a lower bilirubin, lower INR, lack of use of mechanical ventilation and no clinical features of coma at baseline had a higher odds ratio of transplant free survival. The number of deaths were similar between patients with true-IND ALF versus patients with indeterminable ALF (29.8% vs. 27.2%), with almost half of the patients requiring liver transplant (42.1% vs. 45.7%). CONCLUSION: We illustrate the poor prognoses that true-IND-ALF and indeterminable ALF carry and the need for emergency liver transplantation in most cases.

Mortality and Morbidity Among Adult Liver Retransplant Recipients.

BACKGROUND: Liver transplantation (LT) is life-saving procedure for patients with end-stage liver failure with up to 20% of patients suffering graft failure following primary transplantation. Retransplantation (ReLT) remains the only definitive treatment for irreversible graft failure. AIMS: We aimed to explore the postoperative outcomes following liver ReLT. METHODS: Patients who had received a liver transplant between 2003 and 2016 were retrospectively identified using the Scientific Registry of Transplant Recipients (SRTRs). Patients were stratified based on previous liver transplant history. The primary outcomes of this study were 5-year postoperative mortality, morbidity, and length of hospital stay following LT. RESULTS: 60,554 (96%) recipients were first LT recipients and 2524 (4%) were ReLT recipients. Compared with first LT, ReLT recipients had significantly higher rates of mortality (OR 1.93, 95%CI 1.76-2.12), overall morbidity (OR 1.80, 95%CI 1.65-1.96), and prolonged length of stay (OR 1.66, 95%CI 1.52-1.81) on multivariate analysis. Morbidity including cardiovascular (CVD) complications (OR 1.32, 95%CI 1.08-1.60), graft failure (OR 2.18, 95%CI 1.84-2.57), infection (OR 2.13, 95%CI 1.82-2.50), and hemorrhage (OR 2.67, 95%CI 2.00-3.61) were significantly greater in ReLT recipients. Compared to first LT, ReLT patients had a significant increase in overall 5-year mortality (p < 0.001), 5-year mortality due to CVD complications (p < 0.001), infection (p = 0.009), but not graft failure (p = 0.3543). CONCLUSION: ReLT is associated with higher rates of 5-year mortality, overall morbidity, CVD morbidity, infection, and graft failure. Higher 5-year mortality in ReLT is due to CVD and infections. These results could be used in preoperative patient assessment and prognostic counseling for ReLT.

Role of Hepatitis C Infection in Acute Liver Injury/Acute Liver Failure in North America.

BACKGROUND: While hepatitis A and B are well-known causes of acute liver failure (ALF), few well-documented cases of hepatitis C virus (HCV) infection (absent preexisting liver disease or other liver insults) have been described that result in ALF. We reviewed the Acute Liver Failure Study Group registry for evidence of HCV as a primary or contributing cause to ALF. METHODS: From January 1998 to January 2017, 2,332 patients with ALF (INR ≥ 1.5, any degree of hepatic encephalopathy) and 667 with acute liver injury (ALI; INR ≥ 2.0, no hepatic encephalopathy) were enrolled. Anti-HCV testing was done routinely, with confirmatory RT-PCR testing for HCV RNA where necessary. RESULTS: A total of 136 patients were anti-HCV-antibody positive, as follows: 56 HCV RNA negative, 65 HCV RNA positive, and 8 with no result nor sera available for testing. Only three subjects with ALI/ALF were determined to represent acute HCV infection. Case 1: 47-year-old female with morbid obesity (BMI 52.4) developed ALF and recovered, experiencing anti-HCV seroconversion. Case 2: 37-year-old female using cocaine presented with ALI and fully recovered. Case 3: 54-year-old female developed ALF requiring transplantation and was anti-HCV negative but viremic prior to transplant experiencing anti-HCV seroconversion thereafter. Among 1636 APAP overdose patients, the 52 with concomitant chronic HCV had higher 3-week mortality than the 1584 without HCV (31% vs 17%, p = 0.01). CONCLUSIONS: ALI/ALF solely related to acute hepatitis C infection is very rare. Chronic HCV infection, found in at least 65 (2.2%) of ALI/ALF patients studied, contributed to more severe outcomes in APAP ALI/ALF; ClinicalTrials.gov number, NCT000518440. Trial Registration ClinicalTrials.gov number NCT000518440.

A cost analysis of sorafenib for desmoid tumors.

INTRODUCTION: A recent randomized trial demonstrated that sorafenib improved progression free survival (PFS) in patients with desmoid tumors despite many patients experiencing stable disease or spontaneous regression without treatment. Utilizing these trial data, we performed a cost analysis of sorafenib efficacy through two years of treatment. METHODS: Current Medicare Part D rates for sorafenib were utilized (dose 400 mg/day, cost $309/day). Annual costs per progression and objective response were calculated. Radiologic progression and response were defined using RECIST criteria. Patients with disease progression were separately analyzed in two groups: both clinical and radiologic (CAR), and radiologic alone. RESULTS: 84 previously randomized patients were analyzed (placebo: 35, sorafenib: 49). At one year, sorafenib was associated with a 43% absolute risk reduction (ARR) of CAR progression and number-needed-to-treat (NNT) of 2.3 patients/year, costing $259,406. At two years, ARR was 48% and NNT of 2.1 patients/year, costing $473,697. When evaluating only patients with RECIST defined radiologic progression, sorafenib patients experienced ARR of 13.9% with NNT 7.2 and estimated costs of $812,052 at one year. Two-year ARR was 17.5% with NNT 5.7 and estimated costs $1,285,052. Sorafenib patients experienced improved RECIST partial response rates at 1 and 2 years of 14.7% and 14.3%, with NNT 6.8 and 6.9, and costs of $766,938 and $1,556,433; respectively. CONCLUSION: For the treatment of desmoid tumors, Sorafenib led to improved PFS, but at a significant cost per patient. Favorable RECIST outcomes were less likely and costlier. Patients should be informed of possible benefits of treatment versus potential financial burden.

Association of FDA Mandate Limiting Acetaminophen (Paracetamol) in Prescription Combination Opioid Products and Subsequent Hospitalizations and Acute Liver Failure.

Importance: In January 2011, the US Food and Drug Administration (FDA) announced a mandate to limit acetaminophen (paracetamol) to 325 mg/tablet in combination acetaminophen and opioid medications, with manufacturer compliance required by March 2014. Objective: To assess the odds of hospitalization and the proportion of acute liver failure (ALF) cases with acetaminophen and opioid toxicity prior to and after the mandate. Design, Setting, and Participants: This interrupted time-series analysis used hospitalization data from 2007-2019 involving ICD-9/ICD-10 codes consistent with both acetaminophen and opioid toxicity from the National Inpatient Sample (NIS), a large US hospitalization database, and ALF cases from 1998-2019 involving acetaminophen and opioid products from the Acute Liver Failure Study Group (ALFSG), a cohort of 32 US medical centers. For comparison, hospitalizations and ALF cases consistent with acetaminophen toxicity alone were extracted from the NIS and ALFSG. Exposures: Time prior to and after the FDA mandate limiting acetaminophen to 325 mg in combination acetaminophen and opioid products. Main Outcomes and Measures: Odds of hospitalization involving acetaminophen and opioid toxicity and percentage of ALF cases from acetaminophen and opioid products prior to and after the mandate. Results: In the NIS, among 474 047 585 hospitalizations from Q1 2007 through Q4 2019, there were 39 606 hospitalizations involving acetaminophen and opioid toxicity; 66.8% of cases were among women; median age, 42.2 (IQR, 28.4-54.1). In the ALFSG, from Q1 1998 through Q3 2019, there were a total of 2631 ALF cases, of which 465 involved acetaminophen and opioid toxicity; 85.4% women; median age, 39.0 (IQR, 32.0-47.0). The predicted incidence of hospitalizations 1 day prior to the FDA announcement was 12.2 cases/100 000 hospitalizations (95% CI, 11.0-13.4); by Q4 2019, it was 4.4/100 000 hospitalizations (95% CI, 4.1-4.7) (absolute difference, 7.8/100 000 [95% CI, 6.6-9.0]; P < .001). The odds of hospitalizations with acetaminophen and opioid toxicity increased 11%/y prior to the announcement (odds ratio [OR], 1.11 [95% CI, 1.06-1.15]) and decreased 11%/y after the announcement (OR, 0.89 [95% CI, 0.88-0.90]). The predicted percentage of ALF cases involving acetaminophen and opioid toxicity 1 day prior to the FDA announcement was 27.4% (95% CI, 23.3%-31.9%); by Q3 2019, it was 5.3% (95% CI, 3.1%-8.8%) (absolute difference, 21.8% [95% CI, 15.5%-32.4%]; P < .001). The percentage of ALF cases involving acetaminophen and opioid toxicity increased 7% per year prior to the announcement (OR, 1.07 [95% CI, 1.03-1.1]; P < .001) and decreased 16% per year after the announcement (OR, 0.84 [95% CI, 0.77-0.92]; P < .001). Sensitivity analyses confirmed these findings. Conclusions and Relevance: The FDA mandate limiting acetaminophen dosage to 325 mg/tablet in prescription acetaminophen and opioid products was associated with a statistically significant decrease in the yearly rate of hospitalizations and proportion per year of ALF cases involving acetaminophen and opioid toxicity.

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.