Death and liver transplantation within 2 years of onset of drug-induced liver injury

Novel integrative models to predict the severity of inflammation and fibrosis in patients with drug-induced liver injury

Background and aims

Drug-induced liver injury (DILI) is becoming a worldwide emerging problem. However, few studies focus on the diagnostic performance of non-invasive markers in DILI. This study aims to develop novel integrative models to identify DILI-associated liver inflammation and fibrosis, and compare the predictive values with previously developed indexes.

Methods

A total of 72 DILI patients diagnosed as DILI through liver biopsy were enrolled in this study. Patients were divided into absent-mild (S0-S1, G0-G1) group and moderate-severe (S2-S4, G2-G4) group based on the histological severity of inflammation and fibrosis. We used the area under the receiver operating characteristics curves (AUC) to test the model performances. Backward stepwise regression, best subset and logistic regression models were employed for feature selection and model building. Prediction models were presented with nomogram and evaluated by AUC, Brier score, calibration curves and decision curve analysis (DCA).

Results

For diagnosing moderate-severe inflammation and fibrosis, we calculated the AUC of gamma-glutamyl transpeptidase-to-platelet ratio (GPR), aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis-4 index (FIB-4) and fibrosis-5 index (FIB-5), which were 0.708 and 0.676, 0.778 and 0.667, 0.822 and 0.742, 0.831 and 0.808, respectively. Then, backward stepwise regression, best subset and logistic regression models were conducted for predicting significant liver inflammation and fibrosis. For the prediction of ≥G2 inflammation grade, the AUC was 0.856, 0.822, 0.755, and for the prediction of ≥S2 fibrosis grade, the AUC was 0.889, 0.889, 0.826. Through Brier score, calibration curves and DCA, it was further demonstrated that backward stepwise regression model was highly effective to predict both moderate-severe inflammation and fibrosis for DILI.

Conclusion

The backward stepwise regression model we proposed in this study is more suitable than the existing non-invasive biomarkers and can be conveniently used in the individualized diagnosis of DILI-related liver inflammation and fibrosis.

IQ DILI Consensus Opinion: Best Practices for Rechallenge Following Suspected Drug-Induced Liver Injury in Clinical Trials

Rechallenge with study drug after suspected drug-induced liver injury (DILI) during drug development requires a comprehensive assessment of risks and benefits. Lack of universal consensus or societal guidelines makes this decision-making process more challenging and difficult to manage in clinical development. The sparse published literature is biased towards reporting cases of positive rechallenge (recurrent DILI), often with adverse outcomes. The heterogeneity of available data and inconsistent approaches to drug rechallenge likely lead to bias in our perception of the risks of rechallenge, ultimately leaving this topic controversial. The IQ DILI Causality Assessment Working Group, in collaboration with academic and regulatory experts, developed this manuscript with the following objectives: (1) understand and describe current practices via literature review and survey of practices and opinions among drug developers, academic experts, and regulators; (2) propose a consistent and structured approach to decision-making and managing the rechallenge process; (3) facilitate better understanding of the risks and benefits of rechallenge via a standardized approach to collecting rechallenge data, including outcomes and the importance of publishing rechallenge data; and (4) the role of obtaining a liver biopsy, guidance on when a biopsy might be considered, and what histologic findings can assist in making the rechallenge decision. Lastly, knowledge gaps in the drug rechallenge paradigm are highlighted alongside the proposal to standardize the collection and publication of rechallenge data to help address these gaps. This consensus expert opinion does not encourage rechallenge but provides guidance for drug developers to apply a consistent approach to rechallenge.

Drug-Induced Liver Injury in Patients With Chronic Liver Disease

OBJECTIVE

Drug-induced liver injury (DILI) is a global problem and can develop from exposure to prescription or over-the-counter medications as well as herbal and dietary supplements. The diagnosis of DILI is clinically challenging, and liver injury can be severe leading to liver failure, death, or liver transplantation. Patients with underlying chronic liver diseases (CLD) may be at increased risk for DILI, which is associated with factors related to drug or liver disease.

METHODS

This review summarises current knowledge on the risk and outcomes of DILI in patients with CLD.

RESULTS

Patients with CLD may be at an increased risk for DILI. Additionally patients with underlying CLD are at risk for more severe liver injury and worse outcomes after DILI.

DISCUSSION

The risk for and poor outcomes from DILI are accentuated in patients with CLD and potentially leading to the worst-case scenario of acute-on-chronic liver failure. We highlight the key observations on DILI with a broad range of underlying liver diseases and the high-DILI risk agents implicated in those populations.

Drug-induced liver injury. Part I: Classification, diagnosis and treatment

Drug-induced liver injury (DILI) is a growing clinical problem. Antibiotics remain the most common cause of DILI in Europe. Their clinical spectrum is very broad, from asymptomatic to acute liver failure. Currently, DILI is categorized as hepatocellular (R ≥ 5), cholestatic (R ≤ 2) or mixed (R = 2-5) injury based on the serum alanine aminotransferase (ALT)/alkaline phosphatase (ALP) ratio. DILI is a diagnosis of exclusion and requires a wide differential diagnosis. The most important step in management is discontinuation of the drug suspected of causing liver damage. The list of specific antidotes that eliminate the effects of hepatotoxins is unfortunately very short. In symptomatic treatment, glucocorticosteroids and ursodeoxycholic acid have been used in selected cases. Liver transplantation is an optional treatment in patients with acute liver failure.

Development and Validation of a Novel Model to Discriminate Idiosyncratic Drug-Induced Liver Injury and Autoimmune Hepatitis

BACKGROUND AND AIM

Discriminating between idiosyncratic drug-induced liver injury (DILI) and autoimmune hepatitis (AIH) is critical yet challenging. We aim to develop and validate a machine learning (ML)-based model to aid in this differentiation.

METHODS

This multicenter cohort study utilised a development set from Beijing Friendship Hospital, with retrospective and prospective validation sets from 10 tertiary hospitals across various regions of China spanning January 2009 to May 2023. Different ML algorithms were tested using 24 routine laboratory parameters. The Shapley Additive exPlanations (SHAP) analysis was used to evaluate the contribution of each parameter in the ML model.

RESULTS

A total of 2554 patients (1750 for DILI and 804 for AIH) were included. Using Gradient Boost Decision Tree algorithm, five key parameters-aspartate transaminase, globulin, prealbumin, creatinine and platelet count-were selected to construct the ML model. Consequently, a web-based tool named Beijing-AID (BJ-AID) was developed (http://43.143.153.225:5000/). The BJ-AID model demonstrated excellent discrimination performance, with an area under the receiver operating characteristic curve (AUROC) of 0.94 (95% CI, 0.902-0.975) in the development set, 0.91 (95% CI, 0.900-0.928) in all external validation sets and 0.93 (95% CI, 0.889-0.974) in a prospective validation set. Notably, the BJ-AID model also effectively discriminated atypical cases, including drug-induced autoimmune-like hepatitis and AIH with the history of drug consumption, achieving an AUROC = 0.85 (95% CI, 0.742-0.949).

CONCLUSIONS

We successfully developed and validated a machine learning-based model, BJ-AID, which exhibits a strong discrimination performance. BJ-AID can assist practitioners and hepatologists in diagnosing both typical and atypical cases of DILI and AIH.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05532345.

Drug-induced liver injury: Diagnosis, management and the role of liver transplantation

Drug-induced liver injury (DILI) is caused by various medications or herbals/nutritional supplements resulting in liver test abnormalities or hepatic dysfunction. DILI can be categorized as direct (intrinsic), idiosyncratic, or immune-mediated (indirect), and patterns of injury can be categorized as hepatocellular, cholestatic, or mixed injury. DILI is diagnosed after excluding other causes of liver injury. Cessation of the suspected drug along with supportive care is recommended for most DILI cases. In life-threatening situations, liver transplantation (LT) can be considered; however, the risks with LT and lifelong immunosuppression should be considered. In this paper, we summarize the pathophysiology, diagnosis, medical management, and LT for DILI.

Visualization of Endogenous Hypochlorite in Drug-Induced Liver Injury Mice via a Bioluminescent Probe Combined with Firefly Luciferase mRNA-Loaded Lipid Nanoparticles

Drug-induced liver injury (DILI) is a common liver disease with a high rate of morbidity, and its pathogenesis is closely associated with the overproduction of highly reactive hypochlorite (ClO-) in the liver. However, bioluminescence imaging of endogenous hypochlorite in nontransgenic natural mice remains challenging. Herein, to address this issue, we report a strategy for imaging ClO- in living cells and DILI mice by harnessing a bioluminescent probe formylhydrazine luciferin (ClO-Luc) combined with firefly luciferase (fLuc) mRNA-loaded lipid nanoparticles (LNPs). LNPs could efficiently deliver fLuc mRNA into living cells and in vivo, expressing abundant luciferase in the cytoplasm in situ. In the presence of ClO-, probe ClO-Luc locked by formylhydrazine could release cage-free d-luciferin through oxidation and follow-up hydrolysis reactions, further allowing for bioluminescence imaging. Moreover, based on the luciferase-luciferin system, it was able to sensitively and selectively detect ClO- in vitro with a limit of detection of 0.59 μM and successfully monitor the endogenous hypochlorite generation in the DILI mouse model for the first time. We postulate that this work provides a new method to elucidate the roles of ClO- in related diseases via bioluminescence imaging.

Novel clinical phenotypes, drug categorization, and outcome prediction in drug-induced cholestasis: Analysis of a database of 432 patients developed by literature review and machine learning support

BACKGROUND

Serum transaminases, alkaline phosphatase and bilirubin are common parameters used for DILI diagnosis, classification, and prognosis. However, the relevance of clinical examination, histopathology and drug chemical properties have not been fully investigated. As cholestasis is a frequent and complex DILI manifestation, our goal was to investigate the relevance of clinical features and drug properties to stratify drug-induced cholestasis (DIC) patients, and to develop a prognosis model to identify patients at risk and high-concern drugs.

METHODS

DIC-related articles were searched by keywords and Boolean operators in seven databases. Relevant articles were uploaded onto Sysrev, a machine-learning based platform for article review and data extraction. Demographic, clinical, biochemical, and liver histopathological data were collected. Drug properties were obtained from databases or QSAR modelling. Statistical analyses and logistic regressions were performed.

RESULTS

Data from 432 DIC patients associated with 52 drugs were collected. Fibrosis strongly associated with fatality, whereas canalicular paucity and ALP associated with chronicity. Drugs causing cholestasis clustered in three major groups. The pure cholestatic pattern divided into two subphenotypes with differences in prognosis, canalicular paucity, fibrosis, ALP and bilirubin. A predictive model of DIC outcome based on non-invasive parameters and drug properties was developed. Results demonstrate that physicochemical (pKa-a) and pharmacokinetic (bioavailability, CYP2C9) attributes impinged on the DIC phenotype and allowed the identification of high-concern drugs.

CONCLUSIONS

We identified novel associations among DIC manifestations and disclosed novel DIC subphenotypes with specific clinical and chemical traits. The developed predictive DIC outcome model could facilitate DIC prognosis in clinical practice and drug categorization.

Chinese guideline for the diagnosis and treatment of drug-induced liver injury: an update

Drug-induced liver injury (DILI) is an important adverse drug reaction that can lead to acute liver failure or even death in severe cases. Currently, the diagnosis of DILI still follows the strategy of exclusion. Therefore, a detailed history taking and a thorough and careful exclusion of other potential causes of liver injury is the key to correct diagnosis. This guideline was developed based on evidence-based medicine provided by the latest research advances and aims to provide professional guidance to clinicians on how to identify suspected DILI timely and standardize the diagnosis and management in clinical practice. Based on the clinical settings in China, the guideline also specifically focused on DILI in chronic liver disease, drug-induced viral hepatitis reactivation, common causing agents of DILI (herbal and dietary supplements, anti-tuberculosis drugs, and antineoplastic drugs), and signal of DILI in clinical trials and its assessment.

Hepatotoxicity of newer antiseizure medications in children: an overview and disproportionality analysis of VigiBase

BACKGROUND

We aimed to characterize newer antiseizure medications (ASMs)-induced hepatotoxicity in children and identify signals of disproportionate reporting of hepatotoxicity-related adverse drug events (ADEs).

RESEARCH DESIGN AND METHODS

Case reports reported to VigiBase were accessed using Empirica™ Signal software. To summarize characteristics of the retrieved cases, descriptive statistics were used. A disproportionality analysis was conducted using the Multi-item Gamma Poisson Shrinker algorithm, which calculates Empirical Bayesian Geometric Mean value and its lower and upper 95% confidence limits (EB05 and EB95, respectively). EB05 > 2, N > 0 was considered a signal.

RESULTS

Based on 870 analyzed cases, a higher proportion of cases was reported in girls than in boys and in patients aged 2-11 years than in other age groups. Most cases were serious. In 25 cases, hepatotoxicity resulted in death. A high proportion of patients (n = 275, 31.61%) experienced hypersensitivity reactions, mostly due to lamotrigine. The disproportionality analysis yielded 17 signals concerning felbamate, lamotrigine, levetiracetam, oxcarbazepine, stiripentol, and topiramate. Four signals were for severe liver injury and concerned felbamate, lamotrigine, levetiracetam, and topiramate. Gender-biased reporting frequency was detected for four ASM-ADE combinations.

CONCLUSION

Our results should serve to raise clinicians' awareness about the potential association between several newer ASMs and drug-induced liver injury in children.

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.

Association of BMI with mortality in drug-induced liver injury

BACKGROUND

To clarify the associations between BMI and the incidences of all-cause death or liver-related death (LRD)/liver transplantation (LT) in drug-induced liver injury (DILI).

METHODS

DILI patients from three hospitals were retrospectively retrieved and follow-up from 2009 to 2021. They were categorized into underweight (BMI < 18.5 kg/m 2 ), normal weight (BMI of 18.5-23.9 kg/m 2 ), overweight (BMI of 24-27.9 kg/m 2 ) and obese (BMI ≥ 28 kg/m 2 ) groups. Cox regression models were conducted to reveal the effect of BMI on all-cause death or LRD/LT.

RESULTS

A total of 1469 eligible DILI patients were included: underweight 73 (4.97%), normal weight 811 (55.21%), overweight 473 (32.20%) and obese 112 (7.62%). Eighty-nine patients (6.06%) had all-cause death, of which 66 patients (4.49%) had LRD/LT. The median age was 52 years old, and females were 1039 (70.73%). The associations between BMI and all-cause mortality ( nonlinear test P <  0.01) or liver-related mortality/LT ( nonlinear test P  = 0.01) were J-shaped. Multivariate Cox regression analysis showed that underweight (HR: 3.02, 95% CI: 1.51-6.02) was significantly associated with all-cause mortality after adjusting for age and sex. Furthermore, obese males were significantly associated with liver-related mortality/LT (HR: 3.49, 95% CI: 1.13-10.72) after additional adjustment for serological indices and comorbidities.

CONCLUSION

Association between BMI and mortality is a J-shape. The overall mortality was significantly higher in underweight and obese group. Male obesity is independently associated with LRD/LT. These findings indicate that DILI patients with extreme BMI would have a high risk of dismal outcomes, which warrants extra medical care.

Gut-Liver Axis as a Therapeutic Target for Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a liver disease that remains difficult to predict and diagnose, and the underlying mechanisms are yet to be fully clarified. The gut-liver axis refers to the reciprocal interactions between the gut and the liver, and its homeostasis plays a prominent role in maintaining liver health. It has been recently reported that patients and animals with DILI have a disrupted gut-liver axis, involving altered gut microbiota composition, increased intestinal permeability and lipopolysaccharide translocation, decreased short-chain fatty acids production, and impaired bile acid metabolism homeostasis. The present review will summarize the evidence from both clinical and preclinical studies about the role of the gut-liver axis in the pathogenesis of DILI. Moreover, we will focus attention on the potential therapeutic strategies for DILI based on improving gut-liver axis function, including herbs and phytochemicals, probiotics, fecal microbial transplantation, postbiotics, bile acids, and Farnesoid X receptor agonists.

Roadmap to DILI research in Europe. A proposal from COST action ProEuroDILINet

In the current article the aims for a constructive way forward in Drug-Induced Liver Injury (DILI) are to highlight the most important priorities in research and clinical science, therefore supporting a more informed, focused, and better funded future for European DILI research. This Roadmap aims to identify key challenges, define a shared vision across all stakeholders for the opportunities to overcome these challenges and propose a high-quality research program to achieve progress on the prediction, prevention, diagnosis and management of this condition and impact on healthcare practice in the field of DILI. This will involve 1. Creation of a database encompassing optimised case report form for prospectively identified DILI cases with well-characterised controls with competing diagnoses, biological samples, and imaging data; 2. Establishing of preclinical models to improve the assessment and prediction of hepatotoxicity in humans to guide future drug safety testing; 3. Emphasis on implementation science and 4. Enhanced collaboration between drug-developers, clinicians and regulatory scientists. This proposed operational framework will advance DILI research and may bring together basic, applied, translational and clinical research in DILI.

Deep Learning Algorithm Based on Molecular Fingerprint for Prediction of Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is one the rare adverse drug reaction (ADR) and multifactorial endpoints. Current preclinical animal models struggle to anticipate it, and in silico methods have emerged as a way with significant potential for doing so. In this study, a high-quality dataset of 1573 compounds was assembled. The 48 classification models, which depended on six different molecular fingerprints, were built via deep neural network (DNN) and seven machine learning algorithms. Comparing the results of the DNN and machine learning models, the optional performing model was found as the one developed based on the DNN with ECFP_6 as input, which achieved the area under the receiver operating characteristic curve (AUC) of 0.713, balanced accuracy (BA) of 0.680, and F1 of 0.753. In addition, we used the SHapley Additive exPlanations (SHAP) algorithm to interpret the models, identified the crucial structural fragments related to DILI risk, and selected the top ten substructures with the highest contribution rankings to serve as warning indicators for subsequent drug hepatotoxicity screening studies. The study demonstrates that the DNN models developed based on molecular fingerprints can be a trustworthy and efficient tool for determining the risk of DILI during the pre-development of novel medications.

MELD 3.0 in Advanced Chronic Liver Disease

The MELD (model for end-stage liver disease) 3.0 score was developed to replace the MELD-Na score that is currently used to prioritize liver allocation for cirrhotic patients awaiting liver transplantation in the United States. The MELD 3.0 calculator includes new inputs from patient sex and serum albumin levels and has new weights for serum sodium, bilirubin, international normalized ratio, and creatinine levels. It is expected that use of MELD 3.0 scores will reduce overall waitlist mortality modestly and improve access for female liver transplant candidates. The utility of MELD 3.0 and PELDcre (pediatric end-stage liver disease, creatinine) scores for risk stratification in cirrhotic patients undergoing major abdominal surgery, placement of a transjugular intrahepatic portosystemic shunt, and other interventions requires further study. This article reviews the background of the MELD score and the rationale to create MELD 3.0 as well as potential implications of using this newer risk stratification tool in clinical practice.

Construction of a Label-Detection Integrated Visual Probe to Reveal the Double-Edged Sword Principle of Ferroptosis in Liver Injury

Ferroptosis has been confirmed as a potential mediator and an indicator of the severity of liver injury. Despite the fruitful results, there are still two deficiencies in the research on the association between ferroptosis and liver injury. First, iron ions are usually selected as the target bioanalyte, but its detection based on a fluorescent probe is interfered with by specific chemical reaction mechanisms, leading to low sensitivity and poor physiological stability. Second, more efforts were focused on the harmful effects of ferroptosis on liver injury and less involved in the therapeutic value of ferroptosis for liver injury. Hence, in this work, we proposed a new nonreactive analyte (mitochondrial viscosity) as an analysis marker, which can circumvent the challenges caused by specific reaction mechanisms of iron ions. Meanwhile, we constructed a novel label-detection integrated visual probe (VPF) to explore the feasibility of ferroptosis in the treatment of liver injury. As expected, we not only successfully traced the dynamic changes in mitochondrial viscosity but also visualized the changes in cell morphology during induced and inhibited ferroptosis. Conspicuously, this work revealed that liver injury can be alleviated by regulating ferroptosis, confirming the therapeutic value of ferroptosis in liver injury. In addition, a complex biological communication network between ferroptosis and liver injury was constructed by western blotting, providing an important theoretical mechanism for revealing their double-edged sword relationship. This study not only provides a new strategy for studying the complex relationship between ferroptosis and liver injury but also facilitates the future treatment of liver injury.

A near-infrared fluorescent probe for tracking endogenous and exogenous H2O2 in cells and zebrafish

H2O2 is an important signaling molecule in the body, and its levels fluctuate in many pathological sites, therefore, it can be used as a biomarker for early diagnosis of disease. Since the environment in vivo is extremely complex, it is of great significance to develop a probe that can accurately monitor the fluctuation of H2O2 level without interference from other physiological processes. Based on this, we designed and synthesized two new near-infrared H2O2 fluorescent probes, LTA and LTQ, based on the ICT mechanism. Both of them have good responses to H2O2, but LTA has a faster response speed. In addition, the probe LTA has good biocompatibility, good water solubility, and a large Stokes shift (95 nm). The detection limit is 4.525 μM. The probe was successfully used to visually detect H2O2 in living cells and zebrafish and was successfully used to monitor the changes in H2O2 levels in zebrafish due to APAP-induced liver injury.

Development and validation of a novel model to predict liver-related mortality in patients with idiosyncratic drug-induced liver injury

BACKGROUND

Early identification of patients with high mortality risk is critical for optimizing the clinical management of drug-induced liver injury (DILI). We aimed to develop and validate a new prognostic model to predict death within 6 months in DILI patients.

METHODS

This multicenter study retrospectively reviewed the medical records of DILI patients admitted to three hospitals. A DILI mortality predictive score was developed using multivariate logistic regression and was validated with area under the receiver operating characteristic curve (AUC). A high-mortality-risk subgroup was identified according to the score.

RESULTS

Three independent DILI cohorts, including one derivation cohort (n = 741) and two validation cohorts (n = 650, n = 617) were recruited. The DILI mortality predictive (DMP) score was calculated using parameters at disease onset as follows: 1.913 × international normalized ratio + 0.060 × total bilirubin (mg/dL) + 0.439 × aspartate aminotransferase/alanine aminotransferase - 1.579 × albumin (g/dL) - 0.006 × platelet count (109/L) + 9.662. The predictive performance for 6-month mortality of DMP score was desirable, with an AUC of 0.941 (95% CI: 0.922-0.957), 0.931 (0.908-0.949) and 0.960 (0.942-0.974) in the derivation, validation cohorts 1 and 2, respectively. DILI patients with a DMP score ≥ 8.5 were stratified into high-risk group, whose mortality rates were 23-, 36-, and 45-fold higher than those of other patients in the three cohorts.

CONCLUSIONS

The novel model based on common laboratory findings can accurately predict mortality within 6 months in DILI patients, which should serve as an effective guidance for management of DILI in clinical practice.

γ-Glutamyltranspeptidase-Activated Near-Infrared fluorescent probe for visualization of Drug-Induced liver injury

Drug-induced liver injury (DILI), induced by overdose or chronic administration of drugs, has become the leading cause of acute liver failure. Therefore, an accurate diagnostic method for DILI is critical to improve treatment efficiency. The production of γ-glutamyltranspeptidase (GGT) is closely related to the progression of drug-induced hepatotoxicity. KL-Glu exhibits a prominent GGT-activated NIR fluorescence (734 nm) with a large Stokes shift (137 nm) and good sensitivity/selectivity, making it favorable for real-time detection of endogenous GGT activity. Using this probe, we evaluated the GGT up-regulation under the acetaminophen-induced liver injury model. Moreover, KL-Glu was successfully used to assess liver injury induced by the natural active ingredient triptolide and the effective amelioration upon treatment with N-acetyl cysteine (NAC) or Glutathione (GSH) in cells and in vivo by fluorescent trapping the fluctuation of GGT for the first time. Therefore, the fluorescent probe KL-Glu can be used as a potential tool to explore the function of GGT in the progression of DILI and for the early diagnosis and prognostic evaluation of DILI.

Review of human risk factors for idiosyncratic drug-induced liver injury: latest advances and future goals

INTRODUCTION

Idiosyncratic drug-induced liver injury (DILI) is a common cause of acute liver injury and can lead to death from acute liver failure or require liver transplantation. Although the total burden of liver injury is high, the frequency of DILI caused by specific agents is often low. As the liver injury is by per definition idiosyncratic, the prediction of which patients will develop liver injury from specific drugs is currently a very difficult challenge.

AREAS COVERED

The current paper highlights the most important studies on prediction of DILI published in 2019-2023, including studies on genetic, metabolomic, and demographic risk factors, concomitant medication, and the role of comorbid liver diseases. Risk stratification using demographic, metabolomic, and multigenetic risk factors is discussed.

EXPERT OPINION

Great advances have been made in identifying genetic risk factors for DILI. Combining these risk factors with demographic information and other biomarkers into multigenetic risk models might become highly useful in risk stratifying patients exposed to DILI. However, a more detailed mapping of genetic risk factors is needed. Results of these studies need to be validated in the selected ethnic groups before applicability and cost-effectiveness can be determined.

Repurposing HLA genotype data of renal transplant patients to prevent severe drug hypersensitivity reactions

Introduction: Specific alleles in human leukocyte antigens (HLAs) are associated with an increased risk of developing drug hypersensitivity reactions induced by abacavir, allopurinol, carbamazepine, oxcarbazepine, phenytoin, lamotrigine, or flucloxacillin. Transplant patients are genotyped for HLA as a routine practice to match a potential donor to a recipient. This study aims to investigate the feasibility and potential impact of repurposing these HLA genotype data from kidney transplant patients to prevent drug hypersensitivity reactions. Methods: A cohort of 1347 kidney transplant recipients has been genotyped in the Leiden University Medical Center (LUMC) using next-generation sequencing (NGS). The risk alleles HLA-A*31:01, HLA-B*15:02, HLA-B*15:11, HLA-B*57:01, and HLA-B*58:01 were retrieved from the NGS data. Medical history, medication use, and allergic reactions were obtained from the patient's medical records. Carrier frequencies found were compared to a LUMC blood donor population. Results: A total of 13.1% of transplant cohort patients carried at least one of the five HLA risk alleles and therefore had an increased risk of drug-induced hypersensitivity for specific drugs. HLA-A*31:01, HLA-B*15:02, HLA-B*57:01, and HLA-B*58:01 were found in carrier frequencies of 4.61%, 1.19%, 4.46%, and 3.35% respectively. No HLA-B*15:11 carrier was found. In total nine HLA-B*57:01 carriers received flucloxacillin and seven HLA-B*58:01 carriers within our cohort received allopurinol. Discussion: Our study shows that repurposing HLA genotype data from transplantation patients for the assignment of HLA risk alleles associated with drug hypersensitivity is feasible. The use of these data by physicians while prescribing drugs or by the pharmacist when dispensing drugs holds the potential to prevent drug hypersensitivity reactions. The utility of this method was highlighted by 13.1% of the transplant cohort patients carrying an actionable HLA allele.

Drug-Induced Liver Injury with Commonly Used Antibiotics in the All of Us Research Program

Antibiotics are a known cause of idiosyncratic drug-induced liver injury (DILI). According to the Centers for Disease Control and Prevention, the five most commonly prescribed antibiotics in the United States are azithromycin, ciprofloxacin, cephalexin, amoxicillin, and amoxicillin-clavulanate. We quantified the frequency of acute DILI for these common antibiotics in the All of Us Research Program, one of the largest electronic health record (EHR)-linked research cohorts in the United States. Retrospective analyses were conducted applying a standardized phenotyping algorithm to de-identified clinical data available in the All of Us database for 318,598 study participants. Between February 1984 and December 2022, more than 30% of All of Us participants (n = 119,812 individuals) had been exposed to at least 1 of our 5 study drugs. Initial screening identified 591 potential case patients that met our preselected laboratory-based phenotyping criteria. Because DILI is a diagnosis of exclusion, we then used phenome scanning to narrow the case counts by (i) scanning all EHRs to identify all alternative diagnostic explanations for the laboratory abnormalities, and (ii) leveraging International Classification of Disease 9th revision (ICD)-9 and ICD 10th revision (ICD)-10 codes as exclusion criteria to eliminate misclassification. Our final case counts were 30 DILI cases with amoxicillin-clavulanate, 24 cases with azithromycin, 24 cases with ciprofloxacin, 22 cases with amoxicillin alone, and < 20 cases with cephalexin. These findings demonstrate that data from EHR-linked research cohorts can be efficiently mined to identify DILI cases related to the use of common antibiotics.

The Evolving Profile of Idiosyncratic Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is an infrequent but important cause of liver disease. Newly identified causes of DILI include the COVID vaccines, turmeric, green tea extract, and immune checkpoint inhibitors. DILI is largely a clinical diagnosis of exclusion that requires evaluation for more common causes of liver injury and a compatible temporal association with the suspect drug. Recent progress in DILI causality assessment includes the development of the semi-automated revised electronic causality assessment method (RECAM) instrument. In addition, several drug-specific HLA associations have been identified that can help with the confirmation or exclusion of DILI in individual patients. Various prognostic models can help identify the 5%-10% of patients at highest risk of death. Following suspect drug cessation, 80% of patients with DILI fully recover, whereas 10%-15% have persistently abnormal laboratory studies at 6 months of follow-up. Hospitalized patients with DILI with an elevated international normalized ratio or mental status changes should be considered for N-acetylcysteine therapy and urgent liver transplant evaluation. Selected patients with moderate to severe drug reaction with eosinophilia and systemic symptoms or autoimmune features on liver biopsy may benefit from short-term corticosteroids. However, prospective studies are needed to determine the optimal patients and dose and duration of steroids to use. LiverTox is a comprehensive, freely accessible Web site with important information regarding the hepatotoxicity profile of more than 1000 approved medications and 60 herbal and dietary supplement products. It is hoped that ongoing "omics" studies will lead to additional insight into DILI pathogenesis, improved diagnostic and prognostic biomarkers, and mechanism-based treatments.

Potential benefit and lack of serious risk from corticosteroids in drug-induced liver injury: An international, multicentre, propensity score-matched analysis

BACKGROUND

The use of corticosteroids to treat patients with idiosyncratic drug-induced liver injury (DILI) relies on empirical clinical decisions.

AIM

To investigate the relationship between corticosteroids and risk of acute liver failure (ALF) in patients with DILI and to assess if corticosteroid therapy was associated with improved outcomes in DILI patients.

METHODS

We analysed bona fide idiosyncratic DILI cases from the Spanish DILI Registry and Indiana University School of Medicine. Patients treated with corticosteroids were compared to those who did not receive any treatment. Nearest neighbour propensity score matching analyses were conducted.

RESULTS

We enrolled 724 patients, 106 under corticosteroid therapy, in whom there was over-representation of more severe injury and autoimmune features, and 618 who did not receive any treatment. In an analysis of 80 pairs of propensity score-matched patients, corticosteroid administration was not associated with an increased risk of developing ALF (odds ratio = 0.65; 95% confidence interval [CI]: 0.18-2.40; p = 0.518). Furthermore, in an additional analysis, a Cox regression model that included 41 propensity score-matched pairs showed that patients receiving corticosteroids had a significantly higher normalisation rate of liver enzymes than untreated patients (hazard ratio [HR] = 1.84; 95% CI: 1.02-3.32; p = 0.043), particularly in patients with serious injury who did not resolve within 30 days (HR = 2.79; 95% CI: 1.20-6.50; p = 0.018).

CONCLUSION

Corticosteroid therapy did not worsen outcome in DILI patients. Indeed, corticosteroid administration was associated with a greater rate of normalisation of liver enzymes in patients with serious DILI.

Tandem mass tag-based quantitative proteomic profiling identifies candidate serum biomarkers of drug-induced liver injury in humans

Diagnosis of drug-induced liver injury (DILI) and its distinction from other liver diseases are significant challenges in drug development and clinical practice. Here, we identify, confirm, and replicate the biomarker performance characteristics of candidate proteins in patients with DILI at onset (DO; n = 133) and follow-up (n = 120), acute non-DILI at onset (NDO; n = 63) and follow-up (n = 42), and healthy volunteers (HV; n = 104). Area under the receiver operating characteristic curve (AUC) for cytoplasmic aconitate hydratase, argininosuccinate synthase, carbamoylphosphate synthase, fumarylacetoacetase, fructose-1,6-bisphosphatase 1 (FBP1) across cohorts achieved near complete separation (range: 0.94-0.99) of DO and HV. In addition, we show that FBP1, alone or in combination with glutathione S-transferase A1 and leukocyte cell-derived chemotaxin 2, could potentially assist in clinical diagnosis by distinguishing NDO from DO (AUC range: 0.65-0.78), but further technical and clinical validation of these candidate biomarkers is needed.

Dual-targetable fluorescent probe for mapping the fluctuation of peroxynitrite in drug-induced liver injury model

Drug-induced liver injury (DILI) is one of the most common and serious adverse drug reactions which can cause acute liver failure or even death in severe cases. With the incidence rate increasing over the years, DILI has became a frequent clinical liver disease and a global public health problem. As a biomarker of DILI, the detection of peroxynitrite (ONOO^-) has became a powerful tool for the early diagnosis of liver injury. Here, we synthesized five mitochondria-targetable probes, 1-5, for detecting endogenous ONOO^-. Through dye-screening, probe 5 was stood out by its excellent performance. In the presence of ONOO^-, the fluorescence signal of probe 5 reduced 40-fold in 19 s with a low detection limit (9.36 nM). At the same time, the transformation can be observed with the naked eye under sunlight or UV lamp without being affected by the other reactive species. Even better, with low toxicity and high biocompatibility, probe 5 could successfully detect endogenous ONOO^- in the mitochondrion of cells. Finally, probe 5 could specifically target the liver, and can be employed for monitoring the therapeutic effect of hepatoprotective medicine after drug-induced hepatotoxicity in vivo. In brief, probe 5 has the practical application capability for diagnosing the severity of the liver injury and researching the therapeutic effect of antidote in complex bio-systems.

Plasma Sphingoid Base Profiles of Patients Diagnosed with Intrinsic or Idiosyncratic Drug-induced Liver Injury

Sphingolipids are exceptionally diverse, comprising hundreds of unique species. The bulk of circulating sphingolipids are synthesized in the liver, thereby plasma sphingolipid profiles represent reliable surrogates of hepatic sphingolipid metabolism and content. As changes in plasma sphingolipid content have been associated to exposure to drugs inducing hepatotoxicity both in vitro and in rodents, in the present study the translatability of the preclinical data was assessed by analyzing the plasma of patients with suspected drug-induced liver injury (DILI) and control subjects. DILI patients, whether intrinsic or idiosyncratic cases, had no alterations in total sphingoid base levels and profile composition compared to controls, whereby cardiovascular disease (CVD) was a confounding factor. Upon exclusion of CVD individuals, elevation of 1-deoxysphingosine (1-deoxySO) in the DILI group emerged. Notably, 1-deoxySO values did not correlate with ALT values. While 1-deoxySO was elevated in all DILI cases, only intrinsic DILI cases concomitantly displayed reduction of select shorter chain sphingoid bases. Significant perturbation of the sphingolipid metabolism observed in this small exploratory clinical study is discussed and put into context, in the consideration that sphingolipids might contribute to the onset and progression of DILI, and that circulating sphingoid bases may function as mechanistic markers to study DILI pathophysiology.

Clinical features, outcomes, and HLA risk factors associated with nitrofurantoin-induced liver injury

BACKGROUND & AIMS

Nitrofurantoin (NTF) is widely used for the treatment (short-term) and prevention (long-term) of urinary tract infections. We aimed to describe the clinical characteristics, outcomes, and HLA risk factors for NTF-induced liver injury (NTF-DILI) among individuals enrolled in the Drug Induced Liver Injury Network (DILIN).

METHODS

Seventy-eight individuals with definite, highly likely, or probable NTF-DILI were enrolled into DILIN studies between 2004-2020. HLA alleles were compared between NTF-DILI and three control groups: population (n = 14,001), idiopathic autoimmune hepatitis (n = 231), and non-NTF DILI (n = 661).

RESULTS

Liver injury was hepatocellular in 69% and icteric in 55%. AST > ALT was more common in the 44 long-exposure (≥1 year) NTF-DILI cases than in the 18 short (≤7 days) and 16 intermediate (>7 to <365 days) exposure cases (73% vs. 33% vs. 50%, respectively, p = 0.018), as was ANA or SMA positivity (91% vs. 44% vs. 50%, respectively, p <0.001), and corticosteroid use (61% vs. 27% vs. 44%, respectively, p = 0.06). In long-term NTF-DILI, bridging fibrosis, nodularity or cirrhosis, or clinical and imaging evidence for cirrhosis were present in 38%, with massive or sub-massive necrosis in 20%. No one in the short-term exposure group died or underwent transplantation, whereas 7 (12%) patients from the other groups died or underwent transplantation. After covariate adjustments, HLA-DRB1∗11:04 was significantly more frequent in NTF-DILI compared to population controls (odds ratio [OR] 4.29, p = 1.15 × 10-4), idiopathic autoimmune hepatitis (OR 11.77, p = 7.76 × 10-5), and non-NTF DILI (OR 3.34, p = 0.003).

CONCLUSION

NTF-DILI can result in parenchymal necrosis, bridging fibrosis, cirrhosis, and death or liver transplantation, especially with long-term exposure, and is associated with HLA-DRB1∗11:04. To mitigate against serious liver injury associated with NTF, regulators should revise the prescribing information and consider other mitigation strategies.

IMPACT AND IMPLICATIONS

Nitrofurantoin is a recognized cause of drug-induced liver injury (DILI). In this study consisting of a large cohort of well-phenotyped individuals with nitrofurantoin-induced liver injury, two distinct patterns of liver injury were identified: liver injury associated with short-term exposure, which is generally self-limiting, and liver injury associated with long-term exposure, which can lead to advanced fibrosis, cirrhosis and liver failure. HLA DRB1∗11:04 is a risk factor for liver injury due to long-term nitrofurantoin exposure. Our findings are important for regulators as well as physicians prescribing and pharmacists dispensing nitrofurantoin.

Comparison of the prognostic models for mortality in idiosyncratic drug-induced liver injury

BACKGROUND

Several models have been proposed to predict acute liver failure/death in patients with drug-induced liver injury (DILI), but the predictive performances of them have not been systematically compared. We aim to compare the current models for their predictive potency of mortality at DILI onset.

METHODS

DILI patients hospitalized at both Beijing Friendship Hospital and the Fifth Medical Center of PLA General Hospital were categorized into death/liver transplantation (LT) or survival without LT group. Predictive potency of 28-day, 90-day, 6-month and 12-month death/LT outcomes of Hy's Law, nHy's Law, Robles-Diaz Model, drug-induced liver toxicity (DrILTox ALF) Score, Model for End-stage Liver Disease (MELD) Score, and Ghabril Model was compared by Delong method.

RESULTS

A total of 6.3% (83/1314) patients died or received LT within 12 months after DILI onset. The area under receiver operating characteristic of Hy's Law, nHy's Law, and Robles-Diaz Model was all lower than 0.750 for the prediction of within 12 months' mortality. DrILTox ALF Score, MELD Score and Ghabril Model showed better predictive potency of 28-day [0.896 (0.878-0.912), 0.934 (0.919-0.947), 0.935 (0.921-0.948), respectively], 90-day [0.883 (0.864-0.899), 0.951 (0.938-0.962), 0.952 (0.939-0.963), respectively], 6-month [0.820 (0.799-0.841), 0.905 (0.888-0.921) and 0.908 (0.891-0.923), respectively] and 12-month [0.801 (0.779-0.823), 0.882 (0.863-0.899) and 0.885 (0.866-0.902), respectively] mortality.

CONCLUSION

Despite the difference of clinical characteristics and implicated-drug categories between China and industrialized countries, we demonstrate that MELD Score and Ghabril Model have the best predictive performance in the prediction of mortality within 12 months after DILI onset.

Alanine Aminotransferase and Bilirubin Dynamic Evolution Pattern as a Novel Model for the Prediction of Acute Liver Failure in Drug-Induced Liver Injury

Aims: To develop, optimize, and validate a novel model using alanine aminotransferase (ALT) and total bilirubin (TB) dynamic evolution patterns in predicting acute liver failure (ALF) in drug-induced liver injury (DILI) patients.

Methods: The demographics, clinical data, liver biopsy, and outcomes of DILI patients were collected from two hospitals. According to the dynamic evolution of ALT and TB after DILI onset, the enrolled patients were divided into ALT-mono-peak, TB-mono-peak, double-overlap-peak, and double-separate-peak (DSP) patterns and compared. Logistic regression was used to develop this predictive model in both discovery and validation cohorts.

Results: The proportion of ALF was significantly higher in patients with the DSP pattern than in the ALT-mono-peak pattern and DOP pattern (10.0 vs. 0.0% vs. 1.8%,p &lt; 0.05). The area under receiver operating characteristic curve (AUROC) of the DSP pattern model was 0.720 (95% CI: 0.682–0.756) in the discovery cohort and 0.828 (95% CI: 0.788–0.864) in the validation cohort in predicting ALF, being further improved by combining with international normalized ratio (INR) and alkaline phosphatase (ALP) (AUROC in the discovery cohort: 0.899; validation cohort: 0.958). Histopathologically, patients with the DSP pattern exhibited a predominantly cholestatic hepatitis pattern (75.0%, p &lt; 0.05) with a higher degree of necrosis (29.2%, p = 0.084).

Conclusion: DILI patients with the DSP pattern are more likely to progress to ALF. The predictive potency of the model for ALF can be improved by incorporating INR and ALP. This novel model allows for better identification of high-risk DILI patients, enabling timely measures to be instituted for better outcome.

Prediction of biochemical nonresolution in patients with chronic drug-induced liver injury: A large multicenter study

BACKGROUND AND AIMS

To clarify high-risk factors and develop a nomogram model to predict biochemical resolution or biochemical nonresolution (BNR) in patients with chronic DILI.

APPROACH AND RESULTS

Retrospectively, 3655 of 5326 patients with chronic DILI were enrolled from nine participating hospitals, of whom 2866 underwent liver biopsy. All of these patients were followed up for over 1 year and their clinical characteristics were retrieved from electronic medical records. The endpoint was BNR, defined as alanine aminotransferase or aspartate aminotransferase >1.5× upper limit of normal or alkaline phosphatase >1.1× ULN, at 12 months from chronic DILI diagnosis. The noninvasive high-risk factors for BNR identified by multivariable logistic regression were used to establish a nomogram, which was validated in an independent external cohort. Finally, 19.3% (707 of 3655) patients presented with BNR. Histologically, with the increase in liver inflammation grades and fibrosis stages, the proportion of BNR significantly increased. The risk of BNR was increased by 21.3-fold in patients with significant inflammation compared to none or mild inflammation (p < 0.001). Biochemically, aspartate aminotransferase and total bilirubin, platelets, prothrombin time, sex, and age were associated with BNR and incorporated to construct a nomogram model (BNR-6) with a concordance index of 0.824 (95% CI, 0.798-0.849), which was highly consistent with liver histology. These results were successfully validated both in the internal cohort and external cohort.

CONCLUSIONS

Significant liver inflammation is a robust predictor associated with biochemical nonresolution. The established BNR-6 model provides an easy-to-use approach to assess the outcome of chronic DILI.

Secular Trends in Severe Idiosyncratic Drug-Induced Liver Injury in North America: An Update From the Acute Liver Failure Study Group Registry

INTRODUCTION

Idiosyncratic drug-induced liver injury (DILI) is the second leading cause of acute liver failure (ALF) in the United States. Our study aims were to characterize secular trends in the implicated agents, clinical features, and outcomes of adults with DILI ALF over a 20-year period.

METHODS

Among 2,332 patients with ALF enrolled in the ALF Study Group registry, 277 (11.9%) were adjudicated as idiosyncratic DILI ALF (INR ≥ 1.5 and hepatic encephalopathy) through expert opinion. The 155 cases in era 1 (January 20, 1998-January 20, 2008) were compared with the 122 cases in era 2 (January 21, 2008-January 20, 2018).

RESULTS

Among 277 cases of DILI ALF, 97 different agents, alone or in combination, were implicated: antimicrobials, n = 118 (43%); herbal/dietary supplements (HDS), n = 42 (15%); central nervous system agents/illicit substances, n = 37 (13%); oncologic/biologic agents, n = 29 (10%); and other, n = 51 (18%). Significant trends over time included (i) an increase in HDS DILI ALF (9.7% vs 22%, P < 0.01) and decrease in antimicrobial-induced DILI ALF (45.8% vs. 38.5%, P = 0.03) and (ii) improved overall transplant-free survival (23.5%-38.7%, P < 0.01) while the number of patients transplanted declined (46.4% vs 33.6%, P < 0.03).

DISCUSSION

DILI ALF in North America is evolving, with HDS cases rising and other categories of suspect drugs declining. The reasons for a significant increase in transplant-free survival and reduced need for liver transplantation over time remain unclear but may be due to improvements in critical care, increased NAC utilization, and improved patient prognostication.

Drug-induced liver injury: Pathogenesis, epidemiology, clinical features, and practical management

Drug-induced liver injury (DILI) is an important but rare adverse event which can range from mild liver enzyme elevations to liver failure, transplantation or death. A large proportion of commonly used medications, in addition to herbal and dietary supplements, can cause liver injury. DILI has been categorized as direct or idiosyncratic but indirect liver injury has emerged as a third type of drug-induced liver injury. These types of liver injury may warrant different clinical approach and treatment. Associations of HLA genotypes and risk of DILI have highlighted the importance of the immune system in the pathogenesis of DILI. Furthermore, novel agents affecting the immune response can lead to liver injury, often associated with autoimmune features in serologic tests and liver biopsies. Overall, the diagnosis of DILI remains a challenge as it is requires detailed case evaluation in addition to reviewing the hepatotoxic potentials and clinical signatures of the implicated agents. Biochemical profiles vary between agents and although individual drugs tend to portray a consistent clinicopathologic signature, many drugs have multiple signatures. Thanks to multicenter prospective studies on DILI and websites in the public domain such as LiverTox, physicians are provided with tools to investigate suspected DILI cases to increase the likelihood of establishing adiagnosis. The pathogenesis of DILI, epidemiology and current challenges in the diagnosis and management of the disease are reviewed in the paper.

Herbal and Dietary Supplements-Induced Liver Injury in Latin America: Experience From the LATINDILI Network

BACKGROUND

Herbal and dietary supplements (HDS) consumption, a growing cause of hepatotoxicity, is a common practice among Latin-American populations.

OBJECTIVES

To evaluate clinical, laboratory features and outcome in HDS-hepatotoxicity included in the Latin America-Drug Induced Liver Injury (LATINDILI) Network.

METHODS

A total of 29 adjudicated cases of HDS hepatotoxicity reported to the LATINDILI Network from October 2011 through December 2019 were compared with 322 DILI cases due to conventional drugs and 16 due to anabolic steroids as well as with other series of HDS-hepatotoxicity.

RESULTS

From 367 DILI cases, 8% were attributed to HDS. An increasing trend in HDS-hepatotoxicity was noted over time (p = .04). Camellia sinensis, Herbalife® products, and Garcinia cambogia, mostly used for weight loss, were the most frequently adjudicated causative agents. Mean age was 45 years (66% female). Median time to onset was 31 days. Patients presented typically with hepatocellular injury (83%) and jaundice (66%). Five cases (17%) developed acute liver failure. Compared to conventional medications and anabolic steroids, HDS hepatotoxicity cases had the highest levels of aspartate and alanine transaminase (p = .008 and p = .021, respectively), had more re-exposure events to the culprit HDS (14% vs 3% vs 0%; p = .026), and had more severe and fatal/liver transplantation outcomes (21% vs 12% vs 13%; p = .005). Compared to other DILI cohorts, less HDS hepatotoxicity cases in Latin America were hospitalized (41%).

CONCLUSIONS

HDS-hepatotoxicity in Latin-America affects mainly young women, manifests mostly with hepatocellular injury and is associated with higher frequency of accidental re-exposure. HDS hepatotoxicity is more serious with a higher chance of death/liver transplantation than DILI related to conventional drugs.

Acute-on-Chronic Liver Failure Clinical Guidelines

In patients with cirrhosis and chronic liver disease, acute-on-chronic liver failure is emerging as a major cause of mortality. These guidelines indicate the preferred approach to the management of patients with acute-on-chronic liver failure and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation process. In instances where the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, but there was consensus of significant clinical merit, key concept statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not only, approach to clinical scenarios.

Genotyping for HLA Risk Alleles to Prevent Drug Hypersensitivity Reactions: Impact Analysis

Human Leukocyte Antigen (HLA) variants can be a risk factor for developing potentially fatal drug hypersensitivity reactions. Our aim was to estimate the potential impact of genotyping for the HLA risk alleles incorporated in the Dutch Pharmacogenetics Working Group (DPWG) guidelines in The Netherlands. We estimated the number of hypersensitivity reactions and associated deaths that can be avoided annually by genotyping for these HLA risk alleles. Additionally, the cost-effectiveness was estimated. Nationwide implementation of genotyping HLA risk alleles before initiating drugs with an actionable drug-gene interaction can potentially save the life of seven allopurinol initiators and two flucloxacillin initiators each year in The Netherlands. Besides these deaths, 28 cases of abacavir hypersensitivity, 24 cases of allopurinol induced SCARs, 6 cases of carbamazepine induced DRESS and 22 cases of flucloxacillin induced DILI can be prevented. Genotyping HLA-B*5701 in abacavir initiators has a number needed to genotype of 31 to prevent one case of abacavir hypersensitivity and is cost-saving. Genotyping HLA-B*5801 in allopurinol initiators has a number needed to genotype of 1149 to prevent one case of SCAR but is still cost-effective. Genotyping before initiating antiepileptic drugs or flucloxacillin is not cost-effective. Our results confirm the need for mandatory testing of HLA-B*5701 in abacavir initiators, as indicated in the drug label, and show genotyping of HLA-B*5801 in allopurinol initiators should be considered.

A History of the Assessment of Liver Performance

Content available: Author Interview and Audio Recording.

Drug-induced liver injury at a tertiary care centre in Germany: Model for end-stage liver disease is the best predictor of outcome

BACKGROUND & AIMS

Agents most frequently inducing idiosyncratic drug-induced liver injury (DILI) differ between countries worldwide. Besides, there is no consistent data on the best model predicting mortality or the need for liver transplantation in DILI. We here analysed the DILI cohort of our centre with regard to causative drugs and clinical outcome.

METHODS

A retrospective analysis of 157 consecutive severe DILI patients presenting to our tertiary care centre in Hamburg, Germany, from 2008 to 2018, was performed.

RESULTS

The most frequent putatively causative drugs were phenprocoumon (n = 21), metamizole (n = 17) and flupirtine (n = 6). The mean values of ALT, bilirubin and Model for End-stage Liver Disease (MELD) score at the time of hospitalisation were 1201 U/L (SD: 1169 U/L), 6.8 mg/dL (SD: 7 mg/dL) and 17 (SD: 8). About 71% of all cases were treated with steroids or steroids combined with n-acetylcysteine. About 12.1% of all DILI cases had a poor outcome (liver transplantation and/or death). At the time of admission, MELD score performed better than Hy's law, the ratio (R) or the new ratio (nR) on their own or combined with bilirubin, regarding sensitivity or specificity for poor outcome. MELD score had a c-statistic of 0.847 (95% CI: 0.731-0.964). Furthermore, the cut-off of 18 MELD points had a sensitivity of 88% and a specificity of 72% for poor outcome.

CONCLUSION

Phenprocoumon and metamizole are frequent causative drugs for DILI in Germany. In comparison to other prognostic scores, MELD score ≥18 at the time of admission performed best in our cohort for the prediction of poor outcome in DILI.

Current Models for Predicting Drug-induced Cholestasis: The Role of Hepatobiliary Transport System

Drug-induced cholestasis is the main type of liver disorder accompanied by high morbidity and mortality. Evidence for the role of hepatobiliary pumps in the cholestasis patho-mechanism is constantly increasing. Recognition of the interactions of chemical agents with these transporters at the initial phases of drug discovery can help develop new drug candidates with low cholestasis potential. This review delivers an outline of the role of these transport proteins in bile creation. It addresses the pathophysiological mechanism for drug-induced cholestasis. In-vitro models, including cell-based and membrane-based approaches and In-vivo models such as genetic knockout animals, are considered. The benefits and restrictions of each model are discussed in this review. Current understandings into the cellular and molecular process that control the activity of hepatobiliary pumps have directed to a better understanding of the pathophysiology of drug-induced cholestasis. A combination of in-vitro monitoring for transport interaction, in-silico predicting systems, and consideration of and metabolic and physicochemical properties must cause more effective monitoring of possible liver problems.

Clinical management of patients with drug-induced liver injury (DILI)

Drug-induced liver injury (DILI) should be considered in all patients with recent elevation of liver tests without obvious etiology and normal hepatobiliary imaging. There is currently no biomarker that is helpful in diagnosis which relies on clinical and laboratory findings. Diagnosis is dependent on temporal relationship with a recently started drug or herbal and dietary supplement and elevated liver tests with exclusion of competing etiologies. The implicated agent should be discontinued and the patient should be observed closely. This is particularly important in patients with jaundice who have approximately 10% risk of liver related mortality and/or need for liver transplantation. There is no specific therapy for DILI which is only symptomatic such as for itching. Patients with jaundice and coagulopathy usually require hospitalization.

Analytical and Omics-Based Advances in the Study of Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a significant clinical issue, affecting 1-1.5 million patients annually, and remains a major challenge during drug development-toxicity and safety concerns are the second-highest reason for drug candidate failure. The future prevalence of DILI can be minimized by developing a greater understanding of the biological mechanisms behind DILI. Both qualitative and quantitative analytical techniques are vital to characterizing and investigating DILI. In vitro assays are capable of characterizing specific aspects of a drug's hepatotoxic nature and multiplexed assays are capable of characterizing and scoring a drug's association with DILI. However, an even deeper insight into the perturbations to biological pathways involved in the mechanisms of DILI can be gained through the use of omics-based analytical techniques: genomics, transcriptomics, proteomics, and metabolomics. These omics analytical techniques can offer qualitative and quantitative insight into genetic susceptibilities to DILI, the impact of drug treatment on gene expression, and the effect on protein and metabolite abundance. This review will discuss the analytical techniques that can be applied to characterize and investigate the biological mechanisms of DILI and potential predictive biomarkers.

A Multiple Logistic Regression Model Based on Gamma-Glutamyl Transferase as a Biomarker for Early Prediction of Drug-Induced Liver Injury in Vietnamese Patients

The discovery of new biomarkers and the causality of drug-induced liver injury (DILI) is a major focus in modern medicine. Alcoholism is considered a risk factor for DILI. However, the extraction and assessment of alcohol history are difficult due to noncooperation by patients and intermittent management. Therefore, we conducted a case-control study of 1277 patients diagnosed with DILI according to the Roussel Uclaf Causality Assessment Method scale to evaluate gamma-glutamyl transferase (GGT) as a biomarker for predicting DILI in Vietnamese patients, where the proportion of alcoholism is quite high. Further, we built and validated a logistic regression model to predict the risk of DILI in hospitalized patients. The risk of DILI increased by 10% for 1 UI/L higher levels of GGT before prescription (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.00-1.01). A history of alcoholism was not a risk factor for DILI occurrence (OR, 1.83; 95%CI, 0.99-3.04; P = .057). A logistic regression model was successfully built and validated based on age; sex; initial levels of alanine aminotransferase, alkaline phosphatate, GGT, likelihood score of the suspected drug, and history of liver disease; the area under the receiver operating characteristic curve of the model was 0.883 (95%CI, 0.868-0.897). Our results thus suggest the necessity of exercising caution when prescribing to patients without a history of alcoholism but having high GGT levels. This model can be applied clinically to assess the risk of DILI before prescribing to reduce the risk of DILI in the patient.

Liver injury associated with drug intake during pregnancy

Drug use during pregnancy is not common. Drug-induced liver injury (DILI) is a potential complication that is rare but can adversely affect both the mother and the fetus. Although many drugs can directly cause hepatotoxicity, idiosyncratic liver injury is common in pregnancy. Underreporting of adverse drug reactions, lack of adequate literature regarding drug safety in pregnancy, and the inherent difficulty in diagnosing DILI during pregnancy make the management of this condition challenging. This review attempts to describe the existing literature regarding DILI in pregnancy, which is mainly in the form of case reports; several studies have looked at the safety of antithyroid drugs, antiretroviral drugs, and paracetamol, which have an indication for use in pregnancy; the relevant data from these studies with regard to DILI has been presented. In addition, the review describes the diagnosis of DILI, grading the disease severity, assessment of causality linking the drug to the adverse event, regulatory guidelines for evaluating the potential of drugs to cause liver injury, efforts to ensure better participation of women in clinical trials and studies in pregnant women population in particular, and the challenges involved in generating adequate research evidence. The establishment of DILI registries in various countries is an encouraging development; however, there is a need for promoting active, spontaneous reporting of adverse events during pregnancy to ensure rapid generation of evidence regarding the safety of a drug in pregnant women.

Incidence and risk factors of anti-tuberculosis drug induced liver injury (DILI): Large cohort study involving 4652 Chinese adult tuberculosis patients

BACKGROUND AND AIMS

Anti-tuberculosis drugs remain as an important cause of drug-induced liver injury (DILI) worldwide. Adverse drug reactions reduce the effectiveness of treatment. We aimed to determine the incidence and risk factors associated with anti-tuberculosis DILI (ATDILI).

METHODS

Using established criteria and causality assessment methods, risk factors for ATDILI were identified in a contemporary cohort and validated in another cohort prospectively. Independent determinants of ATDILI were identified using Cox regression analysis.

RESULTS

In the derivation cohort (n = 3155), 170 (5.4%) developed ATDILI of which 27 (15.9%) developed jaundice; 9(5.3%) developed acute liver failure (ALF) and 3 died. Among HBsAg positive patients, 11/27 (40.7%) of ATDILI developed after 3 months of starting treatment. In addition, of 218 (6.9%) who developed raised alanine transferase (ALT) levels ≥3 times upper limit normal, 193 (88.5%) resolved and 25 (11.4%) progressed to DILI. Age (HR = 1.014, 95% CI: 1.005-1.023), baseline ALT (HR = 1.014, 95% CI: 1.003-1.024), haemoglobin (HR = 1.011, 95% CI: 1.002-1.020) and HBsAg positivity (HR = 1.516, 95% CI: 1.004-2.290) were independent risk factors for DILI. In the second cohort (n = 1497) of which 85 (5.7%) developed ATDILI. Age (HR = 1.029, 95% CI: 1.003-1.056), baseline AST (HR = 1.036, 95% CI: 1.010-1.062), previous TB treatment (HR = 3.894, 95% CI: 1.304-11.625) and active drinking (HR = 3.624, 95% CI: 1.147-11.454) were risk factors for developing jaundice.

CONCLUSION

Elevation of ALT of ≥3 × ULN during anti-TB treatment resolves in the vast majority without developing serious consequences. In two cohorts involving 4652 patients, incidence of ALF and death because of ATDILI are low. Age, baseline ALT, haemoglobin and HBsAg positivity are risk factors for the development of DILI and these inform monitoring and management of these patients.