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

Comprehensive analysis and insights gained from long-term experience of the Spanish DILI Registry

BACKGROUND & AIMS

Prospective drug-induced liver injury (DILI) registries are important sources of information on idiosyncratic DILI. We aimed to present a comprehensive analysis of 843 patients with DILI enrolled into the Spanish DILI Registry over a 20-year time period.

METHODS

Cases were identified, diagnosed and followed prospectively. Clinical features, drug information and outcome data were collected.

RESULTS

A total of 843 patients, with a mean age of 54 years (48% females), were enrolled up to 2018. Hepatocellular injury was associated with younger age (adjusted odds ratio [aOR] per year 0.983; 95% CI 0.974-0.991) and lower platelet count (aOR per unit 0.996; 95% CI 0.994-0.998). Anti-infectives were the most common causative drug class (40%). Liver-related mortality was more frequent in patients with hepatocellular damage aged ≥65 years (p = 0.0083) and in patients with underlying liver disease (p = 0.0221). Independent predictors of liver-related death/transplantation included nR-based hepatocellular injury, female sex, higher onset aspartate aminotransferase (AST) and bilirubin values. nR-based hepatocellular injury was not associated with 6-month overall mortality, for which comorbidity burden played a more important role. The prognostic capacity of Hy's law varied between causative agents. Empirical therapy (corticosteroids, ursodeoxycholic acid and MARS) was prescribed to 20% of patients. Drug-induced autoimmune hepatitis patients (26 cases) were mainly females (62%) with hepatocellular damage (92%), who more frequently received immunosuppressive therapy (58%).

CONCLUSIONS

AST elevation at onset is a strong predictor of poor outcome and should be routinely assessed in DILI evaluation. Mortality is higher in older patients with hepatocellular damage and patients with underlying hepatic conditions. The Spanish DILI Registry is a valuable tool in the identification of causative drugs, clinical signatures and prognostic risk factors in DILI and can aid physicians in DILI characterisation and management.

LAY SUMMARY

Clinical information on drug-induced liver injury (DILI) collected from enrolled patients in the Spanish DILI Registry can guide physicians in the decision-making process. We have found that older patients with hepatocellular type liver injury and patients with additional liver conditions are at a higher risk of mortality. The type of liver injury, patient sex and analytical values of aspartate aminotransferase and total bilirubin can also help predict clinical outcomes.

ACG Clinical Guideline: Diagnosis and Management of Idiosyncratic Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is common in gastroenterology and hepatology practices, and it can have multiple presentations, ranging from asymptomatic elevations in liver biochemistries to hepatocellular or cholestatic jaundice, liver failure, or chronic hepatitis. Antimicrobials, herbal and dietary supplements, and anticancer therapeutics (e.g., tyrosine kinase inhibitors or immune-checkpoint inhibitors) are the most common classes of agents to cause DILI in the Western world. DILI is a diagnosis of exclusion, and thus, careful assessment for other etiologies of liver disease should be undertaken before establishing a diagnosis of DILI. Model for end-stage liver disease score and comorbidity burden are important determinants of mortality in patients presenting with suspected DILI. DILI carries a mortality rate up to 10% when hepatocellular jaundice is present. Patients with DILI who develop progressive jaundice with or without coagulopathy should be referred to a tertiary care center for specialized care, including consideration for potential liver transplantation. The role of systemic corticosteroids is controversial, but they may be administered when a liver injury event cannot be distinguished between autoimmune hepatitis or DILI or when a DILI event presents with prominent autoimmune hepatitis features.

Serious liver injury induced by Nimesulide: an international collaborative study

Nimesulide is a non-steroidal anti-inflammatory drug still marketed in many countries. We aim to analyze the clinical phenotype, outcome, and histological features of nimesulide-induced liver injury (nimesulide-DILI). We analyzed 57 cases recruited from the Spanish and Latin American DILI registries. Causality was assessed by the RUCAM scale. Mean age of the whole case series was 59 years (86% women) with a median time to onset of 40 days. A total of 46 patients (81%) were jaundiced. Nimesulide-DILI pattern was hepatocellular in 38 (67%), mixed in 12 (21%), and cholestatic in 7 (12%) cases. Transaminases were elevated with a mean of nearly 20-fold the upper limit of normality (ULN), while alkaline phosphatase showed a twofold mean elevation above ULN. Total bilirubin showed a mean elevation of 13-fold the ULN. Liver histology was obtained in 14 cases (25%), most of them with a hepatocellular pattern. Median time to recovery was 60 days. Overall, 12 patients (21%) developed acute liver failure (ALF), five (8.8%) died, three underwent liver transplantation (5.3%), and the remaining four resolved. Latency was ≤ 15 days in 12 patients (21%) and one patient developed ALF within 7 days from treatment initiation. Increased total bilirubin and aspartate transaminase levels were independently associated with the development of ALF. In summary, nimesulide-DILI affects mainly women and presents typically with a hepatocellular pattern. It is associated with ALF and death in a high proportion of patients. Shorter (≤ 15 days) duration of therapy does not prevent serious nimesulide hepatotoxicity, making its risk/benefit ratio clearly unfavorable.

Clinical Characteristics and Outcome of Drug-Induced Liver Injury in the Older Patients: From the Young-Old to the Oldest-Old

Older patients with hepatotoxicity have been scarcely studied in idiosyncratic drug-induced liver injury (DILI) cohorts. We sought the distinctive characteristics of DILI in older patients across age groups. A total of 882 DILI patients included in the Spanish DILI Registry (33% ≥ 65 years) were categorized according to age: "young" (< 65 years); "young-old" (65-74 years); "middle-old" (75-84 years); and "oldest-old" (≥ 85 years). All elderly groups had an increasingly higher comorbidity burden (P < 0.001) and polypharmacy (P < 0.001). There was a relationship between jaundice and hospitalization (P < 0.001), and both were more prevalent in the older age groups, especially in the oldest-old (88% and 69%, respectively), and the DILI episode was more severe (P = 0.029). The proportion of females decreased across age groups from the young to the middle-old, yet in the oldest-old there was a distinct female predominance. Pattern of liver injury shifted towards cholestatic with increasing age among top culprit drugs amoxicillin-clavulanate, atorvastatin, levofloxacin, ibuprofen, and ticlopidine. The best cutoff point for increased odds of cholestatic DILI was 65 years. Older patients had increased non-liver-related mortality (P = 0.030) as shown by the predictive capacity of the Model for End-Stage Liver Disease score (odds ratio (OR) = 1.116; P < 0.001), and comorbidity burden (OR = 4.188; P = 0.001) in the 6-month mortality. Older patients with DILI exhibited an increasingly predominant cholestatic phenotype across a range of culprit drugs, other than amoxicillin-clavulanate, with increased non-liver-related mortality and require a different approach to predict outcome. The oldest DILI patients exhibited a particular phenotype with more severe DILI episodes and need to be considered when stratifying older DILI populations.

Use of Dietary Supplements in Pediatric Liver Disease and Transplantation

BACKGROUND

Dietary supplements are frequently used by healthy individuals and those with chronic medical conditions but may cause damage to the liver. The aim of this study was to examine the prevalence and attitudes of dietary supplement use, and the frequency of disclosure to healthcare providers among parents/caregivers for children with chronic liver disease.

METHODS

We developed an anonymous survey for parents/caregivers of children (<18 years old) with chronic liver disease or liver transplant recipients and distributed the survey through social media groups organized around pediatric liver diseases.

RESULTS

The survey was completed by 101 parents/caregivers (48 without transplant and 53 posttransplant).Among respondents, 87% agreed they would use dietary supplements to help their child, but parents/caregivers of transplant recipients were less likely to consider use (77% vs 98%; P = 0.01). In the past 12 months, 83% reported dietary supplement use including 47% who used nonvitamin/mineral supplements. In two-thirds of parents/caregivers, use was initiated by their personal belief. Although 77% of respondents disclosed their use to their liver team, disclosure varied depending on the supplement with no individual that used cannabinoid products disclosing the use.

CONCLUSIONS

Dietary supplements are frequently used by children with liver disease and may exceed use in other pediatric conditions. Though most parents report use to their liver team, disclosure may vary depending on the specific supplement. Providers should take extra measures to review use of supplements with their patients and work to develop trust with their families to obtain accurate disclosure of use.

Hypoxia/reoxygenation exacerbates drug-induced cytotoxicity by opening mitochondrial permeability transition pore: Possible application for toxicity screening

Recently, mitochondrial dysfunction is thought of as an important factor leading to a drug-induced liver injury. Our previous reports show that mitochondria-related toxicity, including respiratory chain inhibition (RCI) and reactive oxygen species (ROS) induction, can be detected by the modification of sugar resource substitution and high oxygen condition. However, this in vitro model does not detect mitochondrial permeability transition (MPT)-induced toxicity. Another study with a lipopolysaccharide-pre-administered rodent model showed that ischemia/reperfusion induced ROS, sensitized the susceptibility of MPT pore opening and, finally developed drug-induced liver toxicity. Based on this result, the present study investigated the effect of hypoxia/reoxygenation (H/R) treatment mimicking the ischemia/reperfusion on MPT-dependent toxicity, aiming to construct a system that can evaluate MPT by drugs in hepatocytes. Mitochondrial ROS were enhanced by H/R treatment only in the galactose culture condition. Amiodarone, benzbromarone, flutamide and troglitazone which induced MPT pore opening led to hepatocyte death only in combination with H/R and galactose. Moreover, this alteration was significantly suppressed in hepatocytes lacking cyclophilin D. In conclusion, MPT-induced cytotoxicity can be detected by activating mitochondrial function and H/R. This cell-based assay system could evaluate MPT induced-cytotoxicity by drugs, besides RCI and ROS induction.

Drug induced liver injury: an update

Drug induced liver injury (DILI) is a relatively rare hepatic condition in response to the use of medications, illegal drugs, herbal products or dietary supplements. It occurs in susceptible individuals through a combination of genetic and environmental risk factors believed to modify drug metabolism and/or excretion leading to a cascade of cellular events, including oxidative stress formation, apoptosis/necrosis, haptenization, immune response activation and a failure to adapt. The resultant liver damage can present with an array of phenotypes, which mimic almost every other liver disorder, and varies in severity from asymptomatic elevation of liver tests to fulminant hepatic failure. Despite recent research efforts specific biomarkers are not still available for routine use in clinical practice, which makes the diagnosis of DILI uncertain and relying on a high degree of awareness of this condition and the exclusion of other causes of liver disease. Diagnostic scales such as the CIOMS/RUCAM can support the causality assessment of a DILI suspicion, but need refinement as some criteria are not evidence-based. Prospective collection of well-vetted DILI cases in established DILI registries has allowed the identification and validation of a number of clinical variables, and to predict a more severe DILI outcome. DILI is also in need of properly designed clinical trials to evaluate the efficacy of new DILI treatments as well as older drugs such as ursodeoxycholic acid traditionally used to ameliorate cholestasis or corticosteroids now widely tried in the oncology field to manage the emergent type of hepatotoxicity related to immune checkpoint inhibitors.

The DILI-sim Initiative: Insights into Hepatotoxicity Mechanisms and Biomarker Interpretation

The drug‐induced liver injury (DILI)‐sim Initiative is a public‐private partnership involving scientists from industry, academia, and the US Food and Drug Administration (FDA). The Initiative uses quantitative systems toxicology (QST) to build and refine a model (DILIsym) capable of understanding and predicting liver safety liabilities in new drug candidates and to optimize interpretation of liver safety biomarkers used in clinical studies. Insights gained to date include the observation that most dose‐dependent hepatotoxicity can be accounted for by combinations of just three mechanisms (oxidative stress, interference with mitochondrial respiration, and alterations in bile acid homeostasis) and the importance of noncompetitive inhibition of bile acid transporters. The effort has also provided novel insight into species and interpatient differences in susceptibility, structure‐activity relationships, and the role of nonimmune mechanisms in delayed idiosyncratic hepatotoxicity. The model is increasingly used to evaluate new drug candidates and several clinical trials are underway that will test the model's ability to prospectively predict liver safety. With more refinement, in the future, it may be possible to use the DILIsym predictions to justify reduction in the size of some clinical trials. The mature model could also potentially assist physicians in managing the liver safety of their patients as well as aid in the diagnosis of DILI.

Economic impacts of alternative kidney transplant immunosuppression: A national cohort study

Understanding the economic implications of induction and maintenance immunosuppression (ISx) is important in developing personalized kidney transplant (KTx) care. Using data from a novel integrated data set including financial records from the University Health System Consortium, Medicare, and pharmacy claims (2007-2014), we estimated the differences in the impact of induction and maintenance ISx regimens on transplant hospitalization costs and Medicare payments from KTx to 3 years. Use of thymoglobulin (TMG) significantly increased transplant hospitalization costs ($12 006; P = .02), compared with alemtuzumab and basiliximab. TMG resulted in lower Medicare payments in posttransplant years 1 (-$2058; P = .05) and 2 (-$1784; P = .048). Patients on steroid-sparing ISx incurred relatively lower total Medicare spending (-$10 880; P = .01) compared with patients on triple therapy (tacrolimus, antimetabolite, and steroids). MPA/AZA-sparing, mammalian target of rapamycin inhibitors-based, and cyclosporine-based maintenance ISx regimens were associated with significantly higher payments. Alternative ISx regimens were associated with different KTx hospitalization costs and longer-term payments. Future studies of clinical efficacy should also consider cost impacts to define the economic effectiveness of alternative ISx regimens.

Epidemiology, Predisposing Factors, and Outcomes of Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is an underreported and underestimated adverse drug reaction. A recent population-based study found a crude incidence of approximately 19 cases per 100,000 a year. Amoxicillin-clavulanate continues to be the most commonly implicated agent in most Western countries, reported to occur in approximately 1 of 2300 users. In patients with drug-induced autoimmune hepatitis, liver tests often do not normalize with cessation of the drugs and require corticosteroids. DILI associated with jaundice can lead to death from liver failure or require liver transplantation in at least 10% of cases.

Drug-Induced Liver Injury: Highlights of the Recent Literature

Drug-induced liver injury (DILI), herbal-induced liver injury, and herbal and dietary supplement (HDS)-induced liver injury are an important aspect of drug safety. Knowledge regarding responsible drugs, mechanisms, risk factors, and the diagnostic tools to detect liver injury have continued to grow in the past year. This review highlights what we considered the most significant publications from among more than 1800 articles relating to liver injury from medications, herbal products, and dietary supplements in 2017 and 2018. The US Drug-Induced Liver Injury Network (DILIN) prospective study highlighted several areas of ongoing study, including the potential utility of human leukocyte antigens and microRNAs as DILI risk factors and new data on racial differences, the role of alcohol consumption, factors associated with prognosis, and updates on the clinical signatures of autoimmune DILI, thiopurines, and HDS agents. Novel data were also generated from the Spanish and Latin American DILI registries as well as from Chinese and Korean case series. A few new agents causing DILI were added to the growing list in the past 2 years, including sodium-glucose co-transporter-2 inhibitors, as were new aspects of chemotherapy-associated liver injury. A number of cases reported previously described hepatotoxins confirmed via the Roussel Uclaf Causality Assessment Method (RUCAM; e.g., norethisterone, methylprednisolone, glatiramer acetate) and/or the DILIN method (e.g., celecoxib, dimethyl fumarate). Additionally, much work centered on elucidating the pathophysiology of DILI, including the importance of bile salt export pumps and immune-mediated mechanisms. Finally, it must be noted that, while hundreds of new studies described DILI in 2017-2018, the quality of such reports must always be addressed. Björnsson reminds us to remain very critical of the data when addressing the future utility of a study, which is why it is so important to adhere to a standardized method such as RUCAM when determining DILI causality. While drug-induced hepatotoxicity remains a diagnosis of exclusion, the diverse array of publications that appeared in 2017 and 2018 provided important advances in our understanding of DILI, paving the way for our improved ability to make a more definitive diagnosis and risk assessment.

Diagnostic and prognostic assessment of suspected drug-induced liver injury in clinical practice

Idiosyncratic drug-induced liver injury (DILI) is a challenging liver disorder because it can present with a range of phenotypes, mimicking almost every other hepatic disease, and lacks specific biomarkers for its diagnosis. Hence, a confident DILI diagnosis is seldom possible as it relies on the precise establishment of a temporal sequence between the exposure to a given prescription drug or sometimes hidden herbal product/over the counter medication as well as the exclusion of other aetiologies of liver disease. However, an accurate diagnosis is of most importance, as prompt withdrawal of the causative agent is essential in DILI management. Indeed, DILI can be severe and even fatal or in a fraction of cases evolve to chronic damage, but specific biomarkers for predicting mortality/liver transplantation or a chronic outcome in the very early phases of DILI are not yet available. In this article, we discuss the best diagnostic and prognostic approach of a DILI suspicion by judiciously choosing and interpreting the standard tests currently used in clinical practice.

Development and Validation of a Model Consisting of Comorbidity Burden to Calculate Risk of Death Within 6 Months for Patients With Suspected Drug-Induced Liver Injury

BACKGROUND & AIMS

Patients with drug-induced liver injury (DILI) frequently have comorbid conditions, but the effects of non-liver comorbidities on outcomes are not well understood. We investigated the association between comorbidity burden and outcomes of patients with DILI, and developed and validated a model to calculate risk of death within 6 months.

METHODS

A multiple logistic regression model identified variables independently associated with death within 6 months of presenting with suspected DILI (6-month mortality) for 306 patients enrolled in the Drug-Induced Liver Injury Network prospective study at Indiana University (discovery cohort). The model was validated using data from 247 patients with suspected DILI enrolled in the same study at the University of North Carolina (validation cohort). Medical comorbidity burden was calculated using the Charlson Comorbidity Index-patients with scores higher than 2 were considered to have significant comorbidities.

RESULTS

Six-month mortality was 8.5% in the discovery cohort and 4.5% in the validation cohort. In the discovery cohort, significant comorbidities (odds ratio, 5.4; 95% confidence interval [CI], 2.1-13.8), Model for End-Stage Liver Disease score (odds ratio, 1.11; 95% CI, 1.04-1.17), and serum level of albumin at presentation (odds ratio, 0.39; 95% CI, 0.2-0.76) were independently associated with 6-month mortality. A model based on these 3 variables identified patients who died within 6 months, with c-statistic values of 0.89 (95% CI, 0.86-0.94) in the discovery cohort and 0.91 (95% CI, 0.83-0.99) in the validation cohort. We developed a web-based calculator for use in the clinic to determine risk of death within 6 months for patients with suspected DILI.

CONCLUSIONS

We developed and validated a model based on comorbidity burden, Model for End-Stage Liver Disease score, and serum level of albumin that predicts 6-month mortality in patients with suspected DILI.

Clinical prospects of biomarkers for the early detection and/or prediction of organ injury associated with pharmacotherapy

Several biomarkers are used to monitor organ damage caused by drug toxicity. Traditional markers of kidney function, such as serum creatinine and blood urea nitrogen are commonly used to estimate glomerular filtration rate. However, these markers have several limitations including poor specificity and sensitivity. A number of serum and urine biomarkers have recently been described to detect kidney damage caused by drugs such as cisplatin, gentamicin, vancomycin, and tacrolimus. Neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid-binding protein (L-FABP), kidney injury molecule-1 (KIM-1), monocyte chemotactic protein-1 (MCP-1), and cystatin C have been identified as biomarkers for early kidney damage. Hy's Law is widely used as to predict a high risk of severe drug-induced liver injury caused by drugs such as acetaminophen. Recent reports have indicated that glutamate dehydrogenase (GLDH), high-mobility group box 1 (HMGB-1), Keratin-18 (k18), MicroRNA-122 and ornithine carbamoyltransferase (OCT) are more sensitive markers of hepatotoxicity compared to the traditional markers including the blood levels of amiotransferases and total bilirubin. Additionally, the rapid development of proteomic technologies in biofluids and tissue provides a new multi-marker panel, leading to the discovery of more sensitive biomarkers. In this review, an update topics of biomarkers for the detection of kidney or liver injury associated with pharmacotherapy.

MRI-based preclinical discovery of DILI: A lesson from paracetamol-induced hepatotoxicity

Worldwide, drug-induced liver injury (DILI) is a major cause of hepatic failure. It is also the leading cause of withdrawal, cautionary labeling, and restricted usage of licensed drugs; therefore, European Medicines Agency (EMA) and United States Food and Drug Administration (FDA) warn that the existing methods of assessing DILI are insufficient and that some of the translational biomarkers of hepatotoxicity must be relooked. Magnetic resonance imaging (MRI) seems to be a proper tool in elucidating the effects of DILI in both preclinical and clinical studies, providing excellent visualization of the morphology of the liver parenchyma. Therefore, herein, we propose preclinical MRI assessment of liver injury in experimental paracetamol-treated rats. Quantitative MRI clearly provides evidence of adverse effects in the liver tissue caused by a single overdose of paracetamol (1 g kg^-1 and 1.5 g kg^-1 b.w.). The results of the MRI were confirmed by the histopathological examination (H&E) of the rat liver specimen, however the adverse effects were not disclosed due to standard aminotransferase assays (ALT/AST) in rat blood serum. The results of our analysis demonstrate the successful application of MRI in the examination of paracetamol-induced hepatotoxicity in rats; it has a potential to serve as the early diagnostic tool for the prediction of DILI in preclinical evaluation.

Drug-induced liver injury

Drug-induced liver injury (DILI) is an adverse reaction to drugs or other xenobiotics that occurs either as a predictable event when an individual is exposed to toxic doses of some compounds or as an unpredictable event with many drugs in common use. Drugs can be harmful to the liver in susceptible individuals owing to genetic and environmental risk factors. These risk factors modify hepatic metabolism and excretion of the DILI-causative agent leading to cellular stress, cell death, activation of an adaptive immune response and a failure to adapt, with progression to overt liver injury. Idiosyncratic DILI is a relative rare hepatic disorder but can be severe and, in some cases, fatal, presenting with a variety of phenotypes, which mimic other hepatic diseases. The diagnosis of DILI relies on the exclusion of other aetiologies of liver disease as specific biomarkers are still lacking. Clinical scales such as CIOMS/RUCAM can support the diagnostic process but need refinement. A number of clinical variables, validated in prospective cohorts, can be used to predict a more severe DILI outcome. Although no pharmacological therapy has been adequately tested in randomized clinical trials, corticosteroids can be useful, particularly in the emergent form of DILI related to immune-checkpoint inhibitors in patients with cancer.

A Single-Center Experience on Outcomes of Complementary and Alternative Medicine Use Among Patients With Cirrhosis

Drug-induced liver injury (DILI) due to complementary and alternative medicine (CAM) use is on the rise throughout the world by patients looking for "safer" alternatives. However, data on acute-on-chronic liver failure (ACLF) due to CAM are lacking. In a large cohort of patients with cirrhosis, we retrospectively studied CAM-related health-seeking behavior and attempted to identify those who developed possible CAM-DILI-related ACLF. In this study, we examine the clinical, biochemical, and liver histopathologic characteristics of possible CAM-DILI-related ACLF, describe implicated CAM agents, and discuss predictors of patient outcomes. Out of 1,666 patients with cirrhosis, 68% used CAM at some point. A total of 35.7% (n = 30/84) patients presented with CAM-related DILI leading to ACLF in the whole CAM-DILI-related decompensation cohort. The most common CAM was unlabeled polyherbal Ayurvedic formulations. Of possible patients with ACLF, 63% self-medicated with CAM based on social media sharing. Mean age ± SD was 51.9 ± 9.9 years, 83% were male patients, median follow-up duration was 173 (range, 14-584) days, median Child-Turcotte-Pugh score was 13 (range, 10-14), Model for End-Stage Liver Disease-sodium score was 30.1 ± 4.8, median chronic liver failure-organ failure (CLIF-C-OF) score was 11 (range, 8-14), and median CLIF-C-ACLF score was 98 (range, 87-127). Portal-based neutrophilic predominant mixed inflammation, hepatocyte ballooning, autoimmune-like features, and severe cholestasis were seen on liver biopsy. Overall, 53% of patients died (median survival 194 days). Baseline overt hepatic encephalopathy and CLIF-C-OF score, total bilirubin, hyponatremia and leukocytosis, and grade of ACLF predicted 1-, 3-, 6- and 12-month mortality, respectively. Conclusion: Possible CAM-DILI-related ACLF has a high mortality. Strict monitoring and identification of CAM use among people with cirrhosis and an integrative public health educational practice can help ameliorate this modifiable risk factor that potentiates heavy liver disease burden and resource use.

EASL Clinical Practice Guidelines: Drug-induced liver injury

Idiosyncratic (unpredictable) drug-induced liver injury is one of the most challenging liver disorders faced by hepatologists, because of the myriad of drugs used in clinical practice, available herbs and dietary supplements with hepatotoxic potential, the ability of the condition to present with a variety of clinical and pathological phenotypes and the current absence of specific biomarkers. This makes the diagnosis of drug-induced liver injury an uncertain process, requiring a high degree of awareness of the condition and the careful exclusion of alternative aetiologies of liver disease. Idiosyncratic hepatotoxicity can be severe, leading to a particularly serious variety of acute liver failure for which no effective therapy has yet been developed. These Clinical Practice Guidelines summarize the available evidence on risk factors, diagnosis, management and risk minimization strategies for drug-induced liver jury.

Identification of serum microRNAs as potential toxicological biomarkers for toosendanin-induced liver injury in mice

BACKGROUND

Toosendan Fructus is traditionally used as an insecticide or digestive tract parasiticide for treating digestive parasites in China. It is recorded to have little toxicity in Chinese Pharmacopoeia and has been found to cause severe liver injury during clinical practice.

PURPOSE

This study aims to identify candidate serum microRNAs (miRNAs) as potential toxicological biomarkers for reflecting the hepatotoxicity induced by toosendanin (TSN), which is the main toxic compound isolated from Toosendan Fructus METHODS: Alanine/aspartate aminotransferase (ALT/AST) activities detection and liver histological observation were performed to evaluate the liver injury induced by TSN or other hepatotoxicants in mice. miRNAs chip analysis and Real-time PCR assay were conducted to identify the altered miRNAs in serum from TSN-treated mice RESULTS: The results of serum ALT/AST and liver histological evaluation showed that TSN (10 mg/kg) induced hepatotoxicity in mice. The results of miRNAs chip showed that the expression of 81 serum miRNAs was obviously altered in mice treated with TSN for 12 h, and 22 of them have passed the further validation in serum from mice treated with TSN for both 6 h and 12 h. These 22 miRNAs were supposed to be the candidate toxicological biomarkers for TSN-induced hepatotoxicity with more sensitivity as compared to the alteration of AST or ALT activity. Moreover, the expression of miRNA-122-3p and mcmv-miRNA-m01-4-3p was not only increased in TSN-treated mice, but also increased in mice treated with other hepatotoxicants including acetaminophen (APAP), monocrotaline (MCT) and diosbuibin B (DB). Only the expression of serum miRNA-367-3p was increased in TSN-treated mice but not changed in the liver injury induced by APAP, MCT or DB CONCLUSION: miR-122-3p and mcmv-miRNA-m01-4-3p may be two commonly sensitive biomarkers for reflecting the hepatotoxicity induced by exogenous hepatotoxicants, and miR-367-3p may be a specific biomarker for reflecting the liver injury induced by TSN.

Tools for causality assessment in drug-induced liver disease

PURPOSE OF REVIEW

There are three liver-specific causality assessment tools currently available to guide clinical diagnosis of Drug-Induced Liver Injury (DILI): Roussel-Uclaf Causality Assessment Method (RUCAM), Digestive-Disease-Week Japan 2004 scale (DDW-J), and Clinical Diagnostic Scale (CDS). The purpose of this review is to assess these tools and discuss how to improve the causality assessment process as a whole.

RECENT FINDINGS

Existing DILI-specific causality assessment tools are surprisingly similar and exhibit only minor differences in point allocation. But difference in threshold for likelihood of being DILI. We reviewed the literature on currently used causality assessment tools, identified areas for future improvement, and herein propose approaches for refinement. Opportunities to improve current models, as well as the assessment process, in general, include in particular provision of more precise clinical detail and to perhaps add new components to scoring systems. For example, the incorporation of drug-specific clinical signature patterns, accounting for a drug's inherent hepatotoxicity potential, and/or incorporation of other drug properties to scoring systems may allow enhancement. Further, more systemic exclusion of competing diagnoses is needed. Finally, causality assessment processes will likely benefit from a data-driven and computer-assisted approach.

SUMMARY

Current tools used for DILI adjudication are imperfect. Avenues to improve these tools are described.

Idiosyncratic drug-induced liver injury in patients: Detection, severity assessment, and regulatory implications

Idiosyncratic Drug-Induced Liver Injury (IDILI) is a rare but potentially life-threatening event that is caused by drugs that, at usual therapeutic doses, do not cause any biochemical or clinical evidence of liver injury in the majority of treated patients. The most common clinical phenotypes of IDILI are "acute hepatitis," "mixed hepatocellular-cholestatic hepatitis," and "cholestatic hepatitis" and these are distinguished by clinical, biochemical and histologic characteristics. Anti-microbials, herbals and dietary supplements are now the agents most often implicated in the US Drug-Induced Liver Injury Network registry. There are several scales that have been used to characterize the severity of IDILI events. There are no reliable means to accurately predict the course of an IDILI event at presentation. In clinical trials, the "gold standard" liver safety signal is the occurrence of "Hy's Law Cases." Making the diagnosis of IDILI, and when a patient is taking multiple drugs, identifying the most likely culprit can be challenging, but many drugs cause IDILI with characteristic clinical and biochemical presentations, or "signatures." In a clinical trial, it is sometimes possible to identify an overlooked "signature" of IDILI by characterizing more minor, asymptomatic, and transient elevations in liver chemistries. This observation can be helpful in assessing causation in rare serious liver events occurring in the clinical trial, or first recognized post-marketing.

Corticosteroid therapy in drug-induced liver injury: Pros and cons

Drug-induced liver injury (DILI) is a liver toxicity induced by a drug or its metabolite. The incidence of DILI continues to increase and it has been an enormous challenge worldwide, while the prognosis is not optimistic. Currently, the most effective treatment for DILI is to suspend the offending drug(s) and to avoid re-exposure, with no definitive therapy available for idiosyncratic DILI with or without acute liver failure. Given the anti-inflammatory effects of corticosteroids, they have been widely used in DILI in clinical practice, although their efficacy remains controversial. Several studies have shown their beneficial effects but a few reports have refuted the efficacy of corticosteroids in treating patients with DILI. In this review, we summarized the history and current status of corticosteroid use in liver diseases and the pros and cons of corticosteroid treatment in DILI, and we explored the DILI candidates who may benefit from corticosteroid therapy, the administration route and dosage, and the adverse effects related to corticosteroid use.

Candidate biomarkers for the diagnosis and prognosis of drug-induced liver injury: An international collaborative effort

Current blood biomarkers are suboptimal in detecting drug-induced liver injury (DILI) and predicting its outcome. We sought to characterize the natural variabilty and performance characteristics of 14 promising DILI biomarker candidates. Serum or plasma from multiple cohorts of healthy volunteers (n = 192 and n = 81), subjects who safely took potentially hepatotoxic drugs without adverse effects (n = 55 and n = 92) and DILI patients (n = 98, n = 28, and n = 143) were assayed for microRNA-122 (miR-122), glutamate dehydrogenase (GLDH), total cytokeratin 18 (K18), caspase cleaved K18, glutathione S-transferase α, alpha-fetoprotein, arginase-1, osteopontin (OPN), sorbitol dehydrogenase, fatty acid binding protein, cadherin-5, macrophage colony-stimulating factor receptor (MCSFR), paraoxonase 1 (normalized to prothrombin protein), and leukocyte cell-derived chemotaxin-2. Most candidate biomarkers were significantly altered in DILI cases compared with healthy volunteers. GLDH correlated more closely with gold standard alanine aminotransferase than miR-122, and there was a surprisingly wide inter- and intra-individual variability of miR-122 levels among healthy volunteers. Serum K18, OPN, and MCSFR levels were most strongly associated with liver-related death or transplantation within 6 months of DILI onset. Prediction of prognosis among DILI patients using the Model for End-Stage Liver Disease was improved by incorporation of K18 and MCSFR levels. Conclusion: GLDH appears to be more useful than miR-122 in identifying DILI patients, and K18, OPN, and MCSFR are promising candidates for prediction of prognosis during an acute DILI event. Serial assessment of these biomarkers in large prospective studies will help further delineate their role in DILI diagnosis and management.

Serum biomarkers of drug-induced liver injury: Current status and future directions

Drug-induced liver injury (DILI), which is caused by drugs and herbal or dietary supplements, remains a serious concern for drug developers, regulators, and clinicians; however, serum biomarkers utilized to detect and monitor DILI have not changed in decades and have limitations. Data-driven mathematical modeling that incorporates the release and clearance kinetics of traditional biomarkers has improved their use in the prediction of liver safety liabilities for new drug candidates. Several newer biomarkers have shown promise in terms of liver specificity, predicting the outcome of DILI events, and providing insight into its underlying mechanisms. For these new biomarkers to be qualified for regulatory acceptance, it will require their assessment in large numbers of patients who are receiving a wide range of compounds and who develop a broad spectrum of liver injuries. The ongoing and evolving international biomarker consortia should play a major role in this effort, which is likely to transform the assessment of liver safety in clinical trials and in the clinic.

The diagnosis and management of idiosyncratic drug-induced liver injury

Drug-induced liver injury (DILI) is an uncommon but important cause of liver disease that can arise after exposure to a multitude of drugs and herbal and dietary supplements. The severity of idiosyncratic DILI varies from mild serum aminotransferase elevations to the development of severe liver injury that can progress to acute liver failure resulting in death or liver transplantation within days of DILI onset. Chronic liver injury that persists for more than 6 months after DILI onset is also becoming increasingly recognized in up to 20% of DILI patients. Host demographic (age, gender, race), clinical and laboratory features at DILI onset have been associated with the severity and outcome of liver injury in DILI patients. In addition to cessation of the suspect drug, other medical interventions including the use of N-acetylcysteine and corticosteroids in selected patients have shown some clinical benefit, but additional prospective studies are needed. A number of promising diagnostic, prognostic and mechanistic serum and genetic biomarkers may help improve our understanding of the pathogenesis and treatment of idiosyncratic DILI.

Idiosyncratic Drug-Induced Acute Liver Failure: A Challenging and Distressing Scenario

BACKGROUND

Idiosyncratic Drug Induced Liver Injury (DILI) is a rare adverse event to drugs that occasionally leads to severe liver damage, being one of the leading causes of Acute Liver Failure (ALF) in developed countries. DILI is largely a diagnosis of exclusion.

DISCUSSION AND CONCLUSION

Careful history of drug taking and ruling out other competing etiologies is mandatory given that DILI can present with an extremely variable phenotype. Several prognostic scores have been developed to promptly identify patients with potential risk of developing ALF. New biomarkers to diagnose and predict DILI evolution are under study and hopefully we will benefit from these novel tools in the near future.

The diagnostic role of miR-122 in drug-induced liver injury: A systematic review and meta-analysis

BACKGROUND

Drug-induced liver injury (DILI) is a potentially severe adverse drug reaction especially in susceptible patients. But there are no sensitive or specific parameters to detecting DILI. The specific expression of miR-122 in the liver has been a hotspot in the evaluation of hepatic toxicity due to its high stability and sensitivity.

METHODS

We performed a systematic literature review through July 31, 2017 to identify studies which evolved DILI patients testing miR-122 without limiting a certain drug. According to the PRISMA statement, a meta-analysis: the diagnostic role of miR-122 in DILI was made. QUADAS-2 quality evaluation table was used to evaluate the quality of the documentary evidence, PRISMA flowchart and quality evaluation table were drawn with RevMan, use Stata to calculate the sensitivity and specificity of miR-122 in diagnosing DILI, ROC curve and Deeks funnel plot were also drawn by STATA.

RESULTS

Eleven studies involved 194 DILI patients and 251 controls, all were tested miR-122 (fold change). Sensitivity of miR-122 in diagnosing DILI was [0.85 (95% CI, 0.75-0.91), I = 53.46%] and specificity was [0.93 (95% CI, 0.86-0.97), I = 65.10%], the area under ROC curve was 0.95 (95% CI, 0.93-0.97). While in acetaminophen (APAP)-induced liver injury, the sensitivity was [0.82 (95%CI, 0.67-0.91), I = 65.77%] specificity was [0.96 (95%CI, 0.88-0.99), I = 31.46%], AUROC was 0.97 (95% CI, 0.95-0.98).

CONCLUSIONS

In this systematic review and meta-analysis, we found miR-122 have a high specificity in DILI, and a modest positive diagnostic effects. On the basis of the limited evidence, further research is needed to evaluate the long-term observation and more clinical data to testify miR-122 in diagnosing DILI.

Risk factors for acute liver failure among inpatients with anti-tuberculosis drug-induced liver injury

Objective

To analyze the clinical and laboratory features and determine the predictors of acute liver failure (ALF) among inpatients with anti-tuberculosis (TB) drug-induced liver injury (DILI).

Method

Patients diagnosed with anti-TB DILI from 2010 to 2016 at The First Affiliated Hospital of Zhejiang University were retrospectively included in this study. Demographic and clinical data were collected by reviewing electronic medical records.

Results

Among 155 inpatients with anti-TB DILI, 55 (35.48%) developed ALF, with an overall mortality of 9.68%. The median time to DILI onset was significantly longer in the ALF compared with the non-ALF group (51 versus 24 days). Eighty-three patients (53.55%) developed DILI (53.55%) within the first month of anti-TB treatment, and 60% of ALF cases occurred within 2 months. Multivariable models for ALF incorporating aspartate aminotransferase, total bilirubin, platelets, white blood cell count, and pre-existing hepatitis yielded a concordance (C-statistic) of 98.93%.

Conclusions

The results of this study suggest that approximately half of all cases of DILI occur within the first month, while 60% of ALF cases occur within 2 months. Elevated total bilirubin, aspartate aminotransferase, white blood cell count, pre-existing hepatitis, and low platelet count are independent risk factors for the development of anti-TB drug-induced ALF.

Cytokine profiles in acute liver injury-Results from the US Drug-Induced Liver Injury Network (DILIN) and the Acute Liver Failure Study Group

Changes in levels of cytokines and chemokines have been proposed as possible biomarkers of tissue injury, including liver injury due to drugs. Recently, in acute drug-induced liver injury (DILI), we showed that 19 of 27 immune analytes were differentially expressed and that disparate patterns of immune responses were evident. Lower values of serum albumin (< 2.8 g/dL) and lower levels of only four analytes, namely, IL-9, IL-17, PDGF-bb, and RANTES, were highly predictive of early death [accuracy = 96%]. The goals of this study were to assess levels of the same 27 immune analytes in larger numbers of subjects to learn whether the earlier findings would be confirmed in new and larger cohorts of subjects, compared with a new cohort of healthy controls. We studied 127 subjects with acute DILI enrolled into the US DILIN. We also studied 118 subjects with severe acute liver injury of diverse etiologies, enrolled into the ALF SG registry of subjects. Controls comprised 63 de-identified subjects with no history of liver disease and normal liver tests. Analytes associated with poor outcomes [death before 6 months, n = 32 of the total of 232 non-acetaminophen (Apap) subjects], were lower serum albumin [2.6 vs 3.0 g/dL] and RANTES [6,458 vs 8,999 pg/mL] but higher levels of IL-6 [41 vs 18], IL-8 [78 vs 48], and MELD scores [30 vs 24]. Similar patterns were observed for outcome of death/liver transplant within 6 months. A model that included only serum albumin < 2.8 g/dL and RANTES below its median value of 11,349 had 83% (or 81%) accuracy for predicting early death (or early death/liver transplant) in 127 subjects from DILIN. No patterns of serum immune analytes were reflective of the etiologies of acute liver failure, but there were cytokine patterns that predicted prognosis in both acute DILI and ALF.

Drug-induced liver injury: a safety review

INTRODUCTION

Idiosyncratic drug-induced liver injury (DILI) remains one of the most important causes of drug attrition both in the early phases of clinical drug development and in the postmarketing scenario. This is because, in spite of emerging data on genetic susceptibility variants associated to the risk of hepatotoxicity, the precise identification of the individual who will develop DILI when exposed to a given drug remains elusive.

AREAS COVERED

In this review, we have addressed recent progress made and initiatives taken in the field of DILI from a safety perspective through a comprehensive search of the literature.

EXPERT OPINION

Despite the substantial progress made over this century, new approaches using big data analysis to characterize the true incidence of DILI are needed and to categorize the drugs' hepatotoxic potential. Genetic studies have highlighted the role of the adaptive immune system yet the mechanisms leading adaptation versus progression remain to be elucidated. There is a compelling need for development and qualification of sensitive, specific, and affordable biomarkers in DILI to foster drug development, patient treatment stratification and, improvement of causality assessment methods. Gaining mechanistic insights in DILI is essential to uncover therapeutic targets and design prospective clinical trials with appropriate endpoints.

Long-Term Outcomes After Drug-Induced Liver Injury

Purpose of the review

This review serves to update the reader on emerging data regarding a spectrum of drug-induced liver injury (DILI) outcomes that lie between complete resolution and acute liver failure. Such outcomes can range from mild chronic injury to late liver failure and mortality.

Recent findings

Several large registries are maturing with large numbers of DILI cases thus shedding light on outcomes including chronic injury and late fatality. We cover definitions commonly used to describe resolution versus chronic injury and mortality due to DILI. We look at rates of occurrence for these different outcomes in major registries. Three specific types of chronic DILI that are illustrative but also easily missed by clinicians are also described.

Summary

A small but important proportion of DILI cases do not resolve, going on to develop chronic injury and even liver failure. Defining and recognizing these cases is a challenge because DILI is rare, and chronic injury rarer still. Large registries are beginning to define these previously overlooked long term outcomes.

Nonacetaminophen Drug-Induced Acute Liver Failure

Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival.

A galactose-mediated targeting nanoprobe for intracellular hydroxyl radical imaging to predict drug-induced liver injury

Drug-induced liver injury (DILI) is a serious concern in modern medicine due to its unpredictability. Currently, biochemical serum markers are being used in DILI detection. However, these biomarker-based methods lack sensitivity and specificity. A high intracellular level of hydroxyl radicals (˙OH) has been regarded as an early indicator of DILI. Therefore, we proposed an ˙OH-responsive and hepatocyte-targeted nanoprobe via conjugation of carboxyfluorescein-labeled DNA and pegylated galactose on the surface of gold nanoparticles. The nanoprobe could bind to a hepatocyte-specific asialoglycoprotein receptor through galactose, and it could be internalized into liver cells. In the presence of high levels of ˙OH in DILI, the DNA could be cleaved to release carboxyfluorescein, leading to remarkable fluorescence enhancement for ˙OH detection. Confocal fluorescence imaging demonstrated that the nanoprobe could be successfully applied in monitoring high ˙OH levels resulting from acetaminophen or triptolide-induced liver injury, which may provide a simple but powerful protocol for the prediction of DILI.

A galactose-mediated targeting nanoprobe has been developed for the accurate imaging of ˙OH to predict drug-induced hepatotoxicity at an early stage.

Clinical presentations and outcomes of bile duct loss caused by drugs and herbal and dietary supplements

Bile duct loss during the course of drug-induced liver injury is uncommon, but can be an indication of vanishing bile duct syndrome (VBDS). In this work, we assess the frequency, causes, clinical features, and outcomes of cases of drug-induced liver injury with histologically proven bile duct loss. All cases of drug-induced liver injury enrolled into a prospective database over a 10-year period that had undergone liver biopsies (n = 363) were scored for the presence of bile duct loss and assessed for clinical and laboratory features, causes, and outcomes. Twenty-six of the 363 patients (7%) with drug-, herbal-, or dietary-supplement-associated liver injury had bile duct loss on liver biopsy, which was moderate to severe (<50% of portal areas with bile ducts) in 14 and mild (50%-75%) in 12. The presenting clinical features of the 26 cases varied, but the most common clinical pattern was a severe cholestatic hepatitis. The implicated agents included amoxicillin/clavulanate (n = 3), temozolomide (n = 3), various herbal products (n = 3), azithromycin (n = 2), and 15 other medications or dietary supplements. Compared to those without, those with bile duct loss were more likely to develop chronic liver injury (94% vs. 47%), which was usually cholestatic and sometimes severe. Five patients died and 2 others underwent liver transplantation for progressive cholestasis despite treatment with corticosteroids and ursodiol. The most predictive factor of poor outcome was the degree of bile duct loss on liver biopsy.

CONCLUSION

Bile duct loss during acute cholestatic hepatitis is an ominous early indicator of possible VBDS, for which at present there are no known means of prevention or therapy. (Hepatology 2017;65:1267-1277).