Development and validation of risk prediction model for bacterial infections in acute liver failure patients.

Infections significantly increase mortality in acute liver failure (ALF) patients, and there are no risk prediction models for early diagnosis and treatment of infections in ALF patients. This study aims to develop a risk prediction model for bacterial infections in ALF patients to guide rational antibiotic therapy. The data of ALF patients admitted to the Second Hospital of Hebei Medical University in China from January 2017 to January 2022 were retrospectively analyzed for training and internal validation. Patients were selected according to the updated 2011 American Association for the Study of Liver Diseases position paper on ALF. Serological indicators and model scores were collected within 24 h of admission. New models were developed using the multivariate logistic regression analysis. An optimal model was selected by receiver operating characteristic (ROC) analysis, Hosmer-Lemeshow test, the calibration curve, the Brier score, the bootstrap resampling, and the decision curve analysis. A nomogram was plotted to visualize the results. A total of 125 ALF patients were evaluated and 79 were included in the training set. The neutrophil-to-lymphocyte ratio and sequential organ failure assessment (SOFA) were integrated into the new model as independent predictive factors. The new SOFA-based model outperformed other models with an area under the ROC curve of 0.799 [95% confidence interval (CI): 0.652-0.926], the superior calibration and predictive performance in internal validation. High-risk individuals with a nomogram score ≥26 are recommended for antibiotic therapy. The new SOFA-based model demonstrates high accuracy and clinical utility in guiding antibiotic therapy in ALF patients.

Acute liver failure in pregnancy.

Liver function abnormalities are noted in a minority of pregnancies with multiple causes for the same. A small proportion of these develop severe liver injury and progress to acute liver failure (ALF). There is a discrete set of etiology for ALF in pregnancy and comprehensive understanding will help in urgent evaluation. Certain diseases such as acute fatty liver of pregnancy, hemolysis, elevated liver enzyme, low platelet (HELLP) syndrome and pre-eclampsia are secondary to pregnant state and can present as ALF. Quick and targeted evaluation with urgent institution of etiology-specific management, especially urgent delivery in patients with pregnancy-associated liver diseases, is the key to avoiding maternal deaths. Pregnancy, as also the fetal life, imparts a further layer of complication in assessment, prognosis and management of these sick patients with ALF. Optimal management often requires a multidisciplinary approach in a well-equipped centre. In this review, we discuss evaluation, assessment and management of pregnant patients with ALF, focussing on approach to pregnancy-associated liver diseases.

Genetic evaluation in indeterminate acute liver failure: A post hoc analysis.

BACKGROUND AND STUDY AIMS: There are limited data regarding indeterminate acute liver failure (ALF). The study aims to perform a post hoc analysis using genetic methods for the ALF cases with indeterminate etiology. PATIENTS AND METHODS: Stored blood samples from these patients with indeterminate ALF were collected. Whole-exome sequencing (WES) was used to evaluate the pathogenesis of indeterminate ALF. RESULTS: A total of 16 samples from 11 adult patients and 5 pediatric patients with indeterminate ALF were available. Among the adult patients, one female patient was identified with two heterozygous variants (c.2333G > T (p.Arg778Leu) and c.2310C > G (p.Leu770 = )) in the adenosine triphosphatase copper-transporting beta (ATP7B) gene, and two male patients were found to harbor heterozygous and homozygous variants (c.686C > A (p.Pro229Gln) plus homozygousvariantA(TA)6TAAinsTA (-), andc.1456 T > G (p.Tyr486Asp) plus c.211G > A (p.Gly71Arg)) in the uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene. For the pediatric patients, single heterozygous variant (c.2890C > T (p.Arg964Cys)) in the polymerase gamma (POLG) gene was found in 1 male child, and two heterozygous variants (c.1909A > G (p.Lys637Glu) and c.3646G > A (p.Val1216Ile)) in the tetratricopeptide repeat domain 37 (TTC37) gene were found in 1 female child. No variants clinically associated with known liver diseases were revealed in the remaining patients. CONCLUSION: These results expand the knowledge of ALF with indeterminate etiology. WES is helpful to reveal possible candidate genes for indeterminate ALF, but incomplete consistency between the genotype and phenotype in some cases still challenge the accurate diagnosis.

Prognostic markers in hepatitis A-related pediatric acute liver failure and validation of the Peds-hepatitis A virus prognostic model.

OBJECTIVES: Hepatitis A virus (HAV) is the commonest cause for pediatric acute liver failure (PALF) in India. The objective of the study was to identify the predictors of mortality and to evaluate the utility of Peds-HAV model in a cohort of non-LT HAV-PALF. METHODS: The study included HAV-related PALF from two non-transplant centers. The predictors of outcome were identified by univariate analysis followed by Cox regression analysis. The prognostic accuracy of Peds-HAV model, King's College Hospital (KCH) criteria and pediatric end-stage liver disease score (PELD) were evaluated. RESULTS: As many as 140 children with PALF were included, of whom 96 (68.6%) children had HAV-PALF. On Cox regression analysis, international normalized ratio (INR) (p < 0.001), jaundice to encephalopathy (JE) interval (p < 0.001) and hepatic encephalopathy (HE) grade 3/4 (p = 0.01) were independent predictors of mortality. The mortality rates were 0% (0/42), 14.3% (3/21), 60% (9/15) and 94.4% (17/18) when none, 1, 2 or 3 criteria of the Peds-HAV were met, respectively. Peds-HAV model at a listing cut-off of  ≥ 2 criteria predicted death with 89.7% sensitivity and 89.6% specificity. In contrast, KCH criteria had a lower sensitivity of 62.1%. PELD score had a sensitivity of 89.7% and specificity of 85.1% at a cut-off of 30. The overall prognostic accuracy of Peds-HAV model (89.6%) was higher than those of KCH (83.3%) and PELD (86.5%). CONCLUSION: INR, HE grade and JE interval were independent predictors of mortality. The study provides an external validation of Peds-HAV model as a prognostic score in HAV-PALF. CLINICAL TRIAL REGISTRY NUMBER: Not applicable as this is a retrospective study.

Acute liver failure.

ABSTRACT: Acute liver failure, commonly caused by acetaminophen overdose, is associated with numerous systemic complications including cerebral edema, hypotension, acute kidney injury, and infection. Management is primarily supportive, with an emphasis on excellent neurocritical care. Although some antidotes and targeted treatments exist, the only definitive treatment remains orthotopic liver transplant.

Unconjugated Hyperbilirubinemia in Acetaminophen-Related Acute Liver Failure.

BACKGROUND In the absence of liver transplantation, the natural history of acetaminophen-induced liver failure is characterized by a progressive increase of liver function tests, including bilirubin mainly as its conjugated form. The presence of high levels of unconjugated bilirubin is more unusual; its etiology is unclear and its prognostic factor has been poorly investigated. CASE REPORT A 52-year-old man with a history of chronic analgesics, alcohol, and illicit drug abuse developed acute liver failure in relationship with the ingestion of largely supra-therapeutic doses of acetaminophen over the days preceding admission. The patient received the classical N-acetylcysteine treatment regimen for acetaminophen overdose. Clinical course was characterized by a progressive worsening of the neurological condition, evolving to grade IV encephalopathy. Coagulation disorders persisted, with factor V level <10%. He fulfilled the criteria for liver transplantation, but this option was rejected after a careful psychiatric evaluation. Laboratory investigations revealed a progressive increase in serum unconjugated bilirubin until his death. As evidence for hemolysis was lacking, acquired deficit in bilirubin glucuronidation appeared likely and diagnosis of Gilbert's syndrome was excluded. CONCLUSIONS After the exclusion of other causes of high unconjugated bilirubin levels, the progressive increase in unconjugated bilirubin can reflect a persistent defect in bilirubin conjugation in relationship with liver centrilobular injury, but the relationship with acetaminophen-glucuronidation is not known and there are insufficient data to affirm that the ratio unconjugated/conjugated bilirubin could be used as a prognostic factor.

Pediatric acute liver failure: Current perspective in etiology and management.

Pediatric acute liver failure (PALF) is a catastrophic clinical condition with very high morbidity and mortality without early detection and intervention. It is characterized by the acute onset of massive hepatocellular injury that releases circulating inflammatory mediators, resulting in metabolic disturbances, coagulopathy, hepatic encephalopathy and multi-organ failure. The etiological spectrum is dominated by hepatotropic viruses, drug-induced liver injury, metabolic and genetic disorders and immune-mediated diseases. Unlike adults, indeterminate causes for acute liver failure constitute a considerable proportion of cases of acute liver failure in children in the west. The heterogeneity of age and etiology in PALF has led to difficulties in developing prognostic scoring. The recent guidelines emphasize prompt identification of PALF, age-appropriate evaluation for hepatic encephalopathy and laboratory evaluation with careful monitoring. Current therapy focuses on supporting the failing liver and other organs, pending either spontaneous recovery or liver transplantation. Targeted therapy is available for a select group of etiologies. Liver transplantation can be lifesaving and a plan for the same should be organized, whenever indicated. The aim of this review is to define PALF, understand its etiopathogenesis, address the challenges encountered during the management and update the latest advances in liver transplantation and non-transplant treatment options in PALF.

[Advancements in the diagnosis and treatment of pediatric acute liver failure]. / 儿童急性肝衰竭的诊治进展.

Pediatric acute liver failure (PALF) is a rare and rapidly progressive clinical syndrome with a poor prognosis and significant mortality. The etiology of PALF is complex, and it presents with diverse and atypical clinical manifestations. Accurate diagnosis based on age-related factors, early recognition or prevention of hepatic encephalopathy, and precise supportive treatment targeting the underlying cause are crucial for improving outcomes and prognosis. This article provides a comprehensive review of recent research on the diagnosis and treatment of PALF, aiming to offer guidance for clinical practice.

Improved mortality prediction for pediatric acute liver failure using dynamic prediction strategy.

OBJECTIVES: To develop and validate a prediction tool for pediatric acute liver failure (PALF) mortality risks that captures the rapid and heterogeneous clinical course for accurate and updated prediction. METHODS: Data included 1144 participants with PALF enrolled during three phases of the PALF registry study over 15 years. Using joint modeling, we built a dynamic prediction tool for mortality by combining longitudinal trajectories of multiple laboratory and clinical variables. The predictive performance for 7-day and 21-day mortality was assessed using the area under curve (AUC) through cross-validation and split-by-time validation. RESULTS: We constructed a prognostic joint model that combines the temporal trajectories of international normalized ratio, total bilirubin, hepatic encephalopathy, platelet count, and serum creatinine. Dynamic prediction using updated information improved predictive performance over static prediction using the information at enrollment (Day 0) only. In cross-validation, AUC increased from 0.784 to 0.887 when measurements obtained between Days 1 and 2 were incorporated. AUC remained similar when we used the earlier subset of the sample for training and the later subset for testing. CONCLUSIONS: Serial measurements of five variables in the first few days of PALF capture the dynamic clinical course of the disease and improve risk prediction for mortality. Continuous disease monitoring and updating risk prognosis are beneficial for timely and judicious medical decisions.

'Double whammy': An Unusual Co-occurrence of Idiosyncratic phenytoin-induced agranulocytosis and acute liver failure in a child.

Idiosyncratic adverse events to phenytoin therapy, such as agranulocytosis and acute liver failure, though rare, may be life-threatening. Simultaneous occurrence of both adverse events is exceedingly rare; only two cases have been reported in the literature to date. We describe such a case in a 15-year-old girl. Prompt haematological and hepatic recovery occurred after discontinuation of the drug. Given the widespread use of phenytoin in seizure disorders, clinicians prescribing this drug should be aware of its potential complications. Early recognition can considerably improve outcomes.

A retrospective study to evaluate Hy's Law, DrILTox ALF score, Robles-Diaz model, and a new logistic regression model for predicting acute liver failure in Chinese patients with drug-induced liver injury.

OBJECTIVES: To evaluate Hy's law, DrILTox ALF Score, Robles-Diaz Model, and a new logistic regression model for predicting acute liver failure (ALF) in Chinese patients with drug-induced liver injury (DILI). METHODS: We conducted a retrospective study among 514 hospitalized DILI patients from 2011 to 2020. Logistic regression analysis was used to develop a predictive model for ALF. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these models were compared. Another 304 DILI patients were used for external validation. OUTCOMES: Twenty-six of 514 DILI patients progressed to ALF. Among these models, Hy's law had 84.6% sensitivity, 59.8% specificity, 10.1% PPV, and 98.6% NPV. DrILTox ALF Score had 92.3% sensitivity, 51.8% specificity, 9.3% PPV, and 99.2% NPV, while Robles-Diaz Model had 50.0% sensitivity, 77.7% specificity, 10.7% PPV, and 96.7% NPV. The logistic regression model described as P = 1/(1+e(1.643 - 0.006* × TBIL (µmol/L) -- 1.302* × INR + 0.095* × ALB (g/L))) had 88.5% sensitivity, 73.1% specificity, 16.3% PPV, and 99.1% NPV at the cut-off of 0.04778 and kept 94.4% sensitivity, 66.8% specificity, 15.2% PPV, and 99.5% NPV in external validation. CONCLUSIONS: The logistic regression model provided superior performance than Hy's law, DrILTox ALF Score, and Robles-Diaz Model for predicting DILI -related ALF.

Genetic landscape of pediatric acute liver failure of indeterminate origin.

BACKGROUND AND AIMS: Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. APPROACH AND RESULTS: With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS: In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation. CONCLUSIONS: This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics.

CHALF Score: A Novel Tool to Rapidly Risk Stratify Children in Need of Liver Transplant Evaluation During Acute Liver Failure.

BACKGROUND: Pediatric acute liver failure (PALF) can require emergent liver transplantation (LT, >25%) or lead to death (~15%). Existing models cannot predict clinical trajectory or survival with native liver (SNL). We aimed to create a predictive model for PALF clinical outcomes based on admission variables. METHODS: A retrospective, single-center PALF cohort (April 2003 to January 2022) was identified using International Classification of Disease codes, selected using National Institutes of Health PALF Study Group (PALFSG) criteria, and grouped by clinical outcome (SNL, LT, or death). Significant admission variables were advanced for feature selection using least absolute shrinkage and selection operator regression with bootstrapping (5000×). A predictive model of SNL versus LT or death was created using logistic regression and validated using PALFSG data. RESULTS: Our single-center cohort included 147 patients (58% SNL, 32% LT, 10% expired), while the PALFSG validation cohort included 492 patients (50% SNL, 35% LT, 15% expired). Admission variables associated with SNL included albumin (odds ratio [OR], 16; P < 0.01), ammonia (OR, 2.37; P < 0.01), and total bilirubin (OR, 2.25; P < 0.001). A model using these variables predicted SNL versus LT or death with high accuracy (accuracy [0.75 training, 0.70 validation], area under the curve [0.83 training, 0.78 validation]). A scaled score (CHLA-acute liver failure score) was created that predicted SNL versus LT or death with greater accuracy (C statistic 0.83) than Pediatric End-Stage Liver Disease (C statistic 0.76) and admission liver injury unit (C statistic 0.76) scores. CONCLUSIONS: The CHLA-acute liver failure score predicts SNL versus LT or mortality in PALF using admission laboratories with high accuracy. This novel, externally validated model offers an objective guide for urgent referral to a pediatric LT center.

TCD assessment in fulminant hepatic failure: Improvements in cerebral autoregulation after liver transplantation.

INTRODUCTION AND OBJECTIVES: Acute liver failure, also known as fulminant hepatic failure (FHF), includes a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction and hepatic encephalopathy. The objective of this study was to assess cerebral autoregulation (CA) in 25 patients (19 female) with FHF and to follow up with seventeen of these patients before and after liver transplantation. PATIENTS AND METHODS: The mean age was 33.8 years (range 14-56, SD 13.1 years). Cerebral hemodynamics was assessed by transcranial Doppler (TCD) bilateral recordings of cerebral blood velocity (CBv) in the middle cerebral arteries (MCA). RESULTS: CA was assessed based on the static CA index (SCAI), reflecting the effects of a 20-30 mmHg increase in mean arterial blood pressure on CBv induced with norepinephrine infusion. SCAI was estimated at four time points: pretransplant and on the 1st, 2nd and 3rd posttransplant days, showing a significant difference between pre- and posttransplant SCAI (p = 0.005). SCAI peaked on the third posttransplant day (p = 0.006). Categorical analysis of SCAI showed that for most patients, CA was reestablished on the second day posttransplant (SCAI > 0.6). CONCLUSIONS: These results suggest that CA impairment pretransplant and on the 1st day posttransplant was re-established at 48-72 h after transplantation. These findings can help to improve the management of this patient group during these specific phases, thereby avoiding neurological complications, such as brain swelling and intracranial hypertension.

Waitlist and posttransplant outcomes of pregnancy-related acute liver failure in the United States.

Data on the liver transplant (LT) outcomes of women with acute liver failure (ALF) due to liver diseases unique to pregnancy (P-ALF) are limited. Using United Network of Organ Sharing (UNOS) data (1987-2021), we analyzed waitlist and post-LT outcomes of ALF in women of childbearing age comparing P-ALF versus ALF due to liver diseases not unique to pregnancy. Baseline characteristics were compared between groups at the time of listing for LT. Of 3542 females aged 16-43 years and listed for LT for ALF, 84 (2%) listed for P-ALF were less likely to be Black (11 vs. 21%, p =0.033), have lower international normalized ratio (2.74 vs. 4.53 p <0.002), but more likely to have respiratory failure (56% vs. 41%, p <0.005), be on pressors (58% vs. 43%, p <0.005), and require dialysis (23% vs. 10%, p <0.001). The cumulative 90-day waitlist mortality (WLM) was lower in P-ALF vs. ALF due to liver diseases not unique to pregnancy (7.4 vs. 16.6%, p <0.001). Posttransplant survival rates at 5 years were similar (82% vs. 79%, p =0.89). In a Fine and Gray regression model controlled for listing year and Model for End-Stage Liver Disease score, 90-day WLM was lower in P-ALF with a sub-HR of 0.42 (95% CI: 0.19-0.94, p =0.035). Of 84 women with P-ALF and listed for LT, 45 listed for hemolysis-elevated liver enzymes-low platelets (HELLP) versus 39 for acute fatty liver of pregnancy had higher 90-day WLM (19.3% vs. 5.7% p <0.005). The 90-day WLM was about 10-fold higher in HELLP versus acute fatty liver of pregnancy with a sub-HR of 9.97 (95% CI: 1.64-60.55, p =0.013). In this UNOS database analysis of ALF among women of childbearing age, the waitlist outcome is better in women with P-ALF compared to women with ALF due to liver diseases not unique to pregnancy. Among women with P-ALF, the 90-day WLM is worse for HELLP versus acute fatty liver of pregnancy. Further studies are needed to improve the management of HELLP and prevent the development of ALF in this subgroup population.

Successful results of early nucleos(t)ide analogue treatment for liver transplantation candidates with severe acute hepatitis B infection.

BACKGROUND: Early treatment of severe acute hepatitis B virus (HBV) infection with nucleos(t)ide analogues may prevent progression to acute liver failure (ALF). PATIENTS AND METHODS: The charts of 24 patients who were treated for severe acute HBV infection (either INR ≥ 1.5 or INR≥ 1.4 and total bilirubin ≥ 20 mg/dL at the referring institution or after admission) between April 2021 and May 2023 (inclusive) were evaluated retrospectively. Twelve patients were women; median [range] age: 48 [35-68]. Entecavir (0.5 mg/day) (n = 16) or tenofovir disoproxil fumarate (245 mg/day) (n =8) were used depending on availability. RESULTS: Two patients required liver transplant which was performed successfully in one (no suitable donor for the other). Deterioration to ALF was prevented in 22 of the 24 cases (92%); these patients could be discharged after median (range) 12 (5-24) days following initiation of the antiviral drug. There was no significant difference in efficacy between the two antiviral agents. The anti-HBsAg antibody became positive in 16 patients (73%); one other patient became HBsAg negative at 1 month after discharge but was lost to follow up. Five patients (23%) are still HBsAg positive but all except one have started treatment in the last 6 months. One of the recently treated 4 patients stopped taking the antiviral drug at his own will and one has become anti-HIV antibody positive during follow up. CONCLUSION: Early treatment of severe acute HBV infection with entecavir or tenofovir disoproxil fumarate prevents the need for liver transplant and consideration of living donors.