Lack of complete biochemical response in autoimmune hepatitis leads to adverse outcome: First report of the IAIHG retrospective registry.

BACKGROUND AND AIMS: The International Autoimmune Hepatitis Group retrospective registry (IAIHG-RR) is a web-based platform with subjects enrolled with a clinical diagnosis of autoimmune hepatitis (AIH). As prognostic factor studies with enough power are scarce, this study aimed to ascertain data quality and identify prognostic factors in the IAIHG-RR cohort. METHODS: This retrospective, observational, multicenter study included all patients with a clinical diagnosis of AIH from the IAIHG-RR. The quality assessment consisted of external validation of completeness and consistency for 29 predefined variables. Cox regression was used to identify risk factors for liver-related death and liver transplantation (LT). RESULTS: This analysis included 2559 patients across 7 countries. In 1700 patients, follow-up was available, with a completeness of individual data of 90% (range: 30-100). During a median follow-up period of 10 (range: 0-49) years, there were 229 deaths, of which 116 were liver-related, and 143 patients underwent LT. Non-White ethnicity (HR 4.1 95% CI: 2.3-7.1), cirrhosis (HR 3.5 95% CI: 2.3-5.5), variant syndrome with primary sclerosing cholangitis (PSC) (HR 3.1 95% CI: 1.6-6.2), and lack of complete biochemical response within 6 months (HR 5.7 95% CI: 3.4-9.6) were independent prognostic factors. CONCLUSIONS: The IAIHG-RR represents the world's largest AIH cohort with moderate-to-good data quality and a relevant number of liver-related events. The registry is a suitable platform for patient selection in future studies. Lack of complete biochemical response to treatment, non-White ethnicity, cirrhosis, and PSC-AIH were associated with liver-related death and LT.

Prior drug allergies are associated with worse outcome in patients with idiosyncratic drug-induced liver injury: A machine learning approach for risk stratification.

The impact of prior drug allergies (PDA) on the clinical features and outcomes of patients who develop idiosyncratic drug-induced liver injury (DILI) is largely unknown. We aimed to assess the clinical presentation and outcomes of DILI patients based on the presence or absence of PDA and explore the association between culprit drugs responsible for DILI and allergy. We analysed a well-vetted cohort of DILI cases enrolled from the Spanish DILI Registry. Bootstrap-enhanced least absolute shrinkage operator procedure was used in variable selection, and a multivariable logistic model was fitted to predict poor outcomes in DILI. Of 912 cases with a first episode of DILI, 61 (6.7%) had documented PDA. Patients with PDA were older (p = 0.009), had higher aspartate aminotransferase (AST) levels (p = 0.047), lower platelet count (p = 0.011) and higher liver-related mortality than those without a history of drug allergies (11% vs. 1.6%, p < 0.001). Penicillin was the most common drug associated with PDA in DILI patients (32%). A model including PDA, nR-based type of liver injury, female sex, AST, total bilirubin, and platelet count showed an excellent performance in predicting poor outcome in patients from the Spanish DILI Registry (area under the ROC curve [AUC] 0.887; 95% confidence interval [CI] 0.794 - 0.981) and the LATINDILI Network (AUC 0.932; 95% CI 0.884 - 0.981). Patients with suspected DILI should be screened for PDA as they would require a close monitoring for early detection of worsening clinical course.

Characterization of drug-induced liver injury associated with drug reaction with eosinophilia and systemic symptoms in two prospective DILI registries.

Idiosyncratic drug-induced liver injury (DILI) associated with drug reactions with eosinophilia and systemic symptoms (DRESS) is poorly characterized among patients of Western countries. We aimed to comprehensively assess the clinical characteristics, outcomes, and causative agents in a prospective, well-vetted cohort of DILI patients with DRESS (DILI-DRESS). We identified 53 DILI-DRESS cases from the Spanish DILI Registry and the Latin American DILI Network. For comparison purposes, we defined a group of DILI patients (n = 881). DILI-DRESS cases were younger (47 vs. 53 years, respectively; p = 0.042) and presented more frequently with cholestatic/mixed damage (p = 0.018). Most DILI-DRESS patients showed moderate liver injury, 13% developed severe damage, and only one patient (with hepatocellular injury due to anti-tuberculosis drugs) progressed to acute liver failure and died. DILI-DRESS cases showed a distinctive causative drug pattern compared to DILI cases. The most frequent drugs were carbamazepine (13%), anti-tuberculosis drugs (13%), amoxicillin-clavulanate (11%), and allopurinol and lamotrigine (7.6% each). Among all cases of DILI due to allopurinol and lamotrigine, 67% presented with a DILI-DRESS phenotype, respectively. Higher total bilirubin (TBL) levels at DILI recognition (odds ratio [OR] 1.23; 95% confidence interval [CI] 1.04-1.45) and absence of eosinophilia (OR 8.77; 95% CI 1.11-69.20) increased the risk for developing a severe-fatal injury in DILI-DRESS patients. DILI-DRESS patients have a more frequent cholestasis/mixed pattern of injury at presentation, with antiepileptics as distinctive causative drug class. Most of the lamotrigine and allopurinol cases present with this phenotype. Higher TBL levels and absence of eosinophilia at DILI recognition are markers of poor outcomes.

Nomenclature, diagnosis and management of drug-induced autoimmune-like hepatitis (DI-ALH): An expert opinion meeting report.

Drug-induced liver injury (DILI) can mimic almost all other liver disorders. A phenotype increasingly ascribed to drugs is autoimmune-like hepatitis (ALH). This article summarises the major topics discussed at a joint International Conference held between the Drug-Induced Liver Injury consortium and the International Autoimmune Hepatitis Group. DI-ALH is a liver injury with laboratory and/or histological features that may be indistinguishable from those of autoimmune hepatitis (AIH). Previous studies have revealed that patients with DI-ALH and those with idiopathic AIH have very similar clinical, biochemical, immunological and histological features. Differentiating DI-ALH from AIH is important as patients with DI-ALH rarely require long-term immunosuppression and the condition often resolves spontaneously after withdrawal of the implicated drug, whereas patients with AIH mostly require long-term immunosuppression. Therefore, revision of the diagnosis on long-term follow-up may be necessary in some cases. More than 40 different drugs including nitrofurantoin, methyldopa, hydralazine, minocycline, infliximab, herbal and dietary supplements (such as Khat and Tinospora cordifolia) have been implicated in DI-ALH. Understanding of DI-ALH is limited by the lack of specific markers of the disease that could allow for a precise diagnosis, while there is similarly no single feature which is diagnostic of AIH. We propose a management algorithm for patients with liver injury and an autoimmune phenotype. There is an urgent need to prospectively evaluate patients with DI-ALH systematically to enable definitive characterisation of this condition.

A new framework for advancing in drug-induced liver injury research. The Prospective European DILI Registry.

BACKGROUND & AIMS: No multi-national prospective study of drug-induced liver injury (DILI) has originated in Europe. The design of a prospective European DILI registry, clinical features and short-term outcomes of the cases and controls is reported. METHODS: Patients with suspected DILI were prospectively enrolled in the United Kingdom, Spain, Germany, Switzerland, Portugal and Iceland, 2016-2021. DILI cases or non-DILI acute liver injury controls following causality assessment were enrolled. RESULTS: Of 446 adjudicated patients, 246 DILI patients and 100 had acute liver injury due to other aetiologies, mostly autoimmune hepatitis (n = 42) and viral hepatitis (n = 34). DILI patients (mean age 56 years), 57% women, 60% with jaundice and 3.6% had pre-existing liver disease. DILI cases and non-DILI acute liver injury controls had similar demographics, clinical features and outcomes. A single agent was implicated in 199 (81%) DILI cases. Amoxicillin-clavulanate, flucloxacillin, atorvastatin, nivolumab/ipilimumab, infliximab and nitrofurantoin were the most commonly implicated drugs. Multiple conventional medications were implicated in 37 (15%) and 18 cases were caused by herbal and dietary supplements. The most common single causative drug classes were antibacterials (40%) and antineoplastic/immunomodulating agents (27%). Overall, 13 (5.3%) had drug-induced autoimmune-like hepatitis due to nitrofurantoin, methyldopa, infliximab, methylprednisolone and minocycline. Only six (2.4%) DILI patients died (50% had liver-related death), and another six received liver transplantation. CONCLUSIONS: In this first multi-national European prospective DILI Registry study, antibacterials were the most commonly implicated medications, whereas antineoplastic and immunomodulating agents accounted for higher proportion of DILI than previously described. This European initiative provides an important opportunity to advance the study on DILI.

Clinical presentation, causative drugs and outcome of patients with autoimmune features in two prospective DILI registries.

BACKGROUND & AIMS: Idiosyncratic drug-induced liver injury (DILI) with autoimmune features is a liver condition with laboratory and histological characteristics similar to those of idiopathic autoimmune hepatitis (AIH), which despite being increasingly reported, remains largely undefined. We aimed to describe in-depth the features of this entity in a large series of patients from two prospective DILI registries. METHODS: DILI cases with autoimmune features collected in the Spanish DILI Registry and the Latin American DILI Network were compared with DILI patients without autoimmune features and with an independent cohort of patients with AIH. RESULTS: Out of 1,426 patients with DILI, 33 cases with autoimmune features were identified. Female sex was more frequent in AIH patients than in the other groups (p = .001). DILI cases with autoimmune features had significantly longer time to onset (p < .001) and resolution time (p = .004) than those without autoimmune features. Interestingly, DILI patients with autoimmune features who relapsed exhibited significantly higher total bilirubin and transaminases at onset and absence of peripheral eosinophilia than those who did not relapse. The likelihood of relapse increased over time, from 17% at 6 months to 50% 4 years after biochemical normalization. Statins, nitrofurantoin and minocycline were the drugs most frequently associated with this phenotype. CONCLUSIONS: DILI with autoimmune features shows different clinical features than DILI patients lacking characteristics of autoimmunity. Higher transaminases and total bilirubin values with no eosinophilia at presentation increase the likelihood of relapse in DILI with autoimmune features. As the tendency to relapse increases over time, these patients will require long-term follow-up.

Evaluation of diagnostic and prognostic candidate biomarkers in drug-induced liver injury vs. other forms of acute liver damage.

AIMS: Detection and characterization of idiosyncratic drug-induced liver injury (DILI) currently rely on standard liver tests, which are suboptimal in terms of specificity, sensitivity and prognosis. Therefore, DILI diagnosis can be delayed, with important consequences for the patient. In this study, we aimed to evaluate the potential of osteopontin, cytokeratin-18 (caspase-cleaved: ccK18 and total: K18), α-glutathione-S-transferase and microRNA-122 as new DILI biomarkers. METHODS: Serial blood samples were collected from 32 DILI and 34 non-DILI acute liver injury (ALI) cases and a single sample from 43 population controls without liver injury (HLC) and analysed using enzyme-linked immunosorbent assay (ELISA) or single-molecule arrays. RESULTS: All biomarkers differentiated DILI and ALI from HLC with an area under receiver operator characteristic curve (AUC) value of >0.75 but were less efficient in distinguishing DILI from ALI, with ccK18 (0.79) and K18 (0.76) demonstrating highest potential. However, the AUC improved considerably (0.98) for ccK18 when comparing DILI and a subgroup of autoimmune hepatitis cases. Cytokeratin-18, microRNA-122 and α-glutathione-S-transferase correlated well with traditional transaminases, while osteopontin correlated most strongly with the international normalized ratio (INR). CONCLUSIONS: ccK18 appears promising in distinguishing DILI from autoimmune hepatitis but less so from other forms of acute liver injury. Osteopontin demonstrates prognostic potential with higher levels detected in more severe cases regardless of aetiology.

Nitrofurantoin-induced liver injury: long-term follow-up in two prospective DILI registries.

Nitrofurantoin is a synthetic antibiotic that is recommended as first-choice treatment for uncomplicated urinary tract infections. The prescription of this drug has increased dramatically, especially in Latin American countries. We described the demographics, clinical characteristics, biochemical features, and outcome of nitrofurantoin-induced liver injury. We analyzed 23 cases from the Latin American DILI Network (LATINDILI) and the Spanish DILI Registry. Causality was assessed with the RUCAM and RECAM scale. Of the 23 DILI cases included in our series, 96% patients were women, and the mean age of the whole cohort was 61 years. The median time of drug exposure was 175 days (interquartile range [IQR] 96-760), with 11 patients who were prescribed nitrofurantoin for more than six months. Hepatocellular damage was the most frequent pattern of liver injury (83%), and nearly half of the patients had an asymptomatic presentation (52%). Neither death nor liver transplantation was documented in this series. Overall, 65% of the patients (n = 15) presented with positive autoantibody titres. The median time to resolution was 81 days (IQR 57-141), and 15 patients (83%) recovered within six months. Five patients (22%) developed nitrofurantoin-induced autoimmune-like hepatitis (NI-AILH), of whom two were characterized by a persistent increase in transaminases that required immunosuppressive treatment to achieve normalization of liver enzymes. Clinicians who prescribe nitrofurantoin should be aware that patients who had taken nitrofurantoin for a long term may be at risk of developing nitrofurantoin-induced autoimmune-like hepatitis.

Microbiota diversity in nonalcoholic fatty liver disease and in drug-induced liver injury.

The gut microbiota could play a significant role in the progression of nonalcoholic fatty liver disease (NAFLD); however, its relevance in drug-induced liver injury (DILI) remains unexplored. Since the two hepatic disorders may share damage pathways, we analysed the metagenomic profile of the gut microbiota in NAFLD, with or without significant liver fibrosis, and in DILI, and we identified the main associated bacterial metabolic pathways. In the NAFLD group, we found a decrease in Alistipes, Barnesiella, Eisenbergiella, Flavonifractor, Fusicatenibacter, Gemminger, Intestinimonas, Oscillibacter, Parasutterella, Saccharoferementans and Subdoligranulum abundances compared with those in both the DILI and control groups. Additionally, we detected an increase in Enterobacter, Klebsiella, Sarcina and Turicibacter abundances in NAFLD, with significant liver fibrosis, compared with those in NAFLD with no/mild liver fibrosis. The DILI group exhibited a lower microbial bacterial richness than the control group, and lower abundances of Acetobacteroides, Blautia, Caloramator, Coprococcus, Flavobacterium, Lachnospira, Natronincola, Oscillospira, Pseudobutyrivibrio, Shuttleworthia, Themicanus and Turicibacter compared with those in the NAFLD and control groups. We found seven bacterial metabolic pathways that were impaired only in DILI, most of which were associated with metabolic biosynthesis. In the NAFLD group, most of the differences in the bacterial metabolic pathways found in relation to those in the DILI and control groups were related to fatty acid and lipid biosynthesis. In conclusion, we identified a distinct bacterial profile with specific bacterial metabolic pathways for each type of liver disorder studied. These differences can provide further insight into the physiopathology and development of NAFLD and DILI.

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.

Incidence and prevalence of acute hepatitis E virus infection in patients with suspected Drug-Induced Liver Injury in the Spanish DILI Registry.

BACKGROUND AND AIMS: Drug-induced liver injury (DILI) presents with a wide phenotypic spectrum requiring an extensive differential diagnosis. Hepatitis E virus (HEV) is not systematically ruled out during acute hepatitis assessment in Spain. The aims of this study were to establish the role of HEV infection and its phenotypic presentation in patients initially suspected of DILI and to determine the anti-HEV seroprevalence rate. METHODS: An analysis of 265 patients with suspected DILI and considered for enrolment in the Spanish DILI Registry and 108 controls with normal liver profiles was undertaken. Anti-HEV Immunoglobulin (Ig) G antibodies were analysed in serum from all subjects. In those with serum samples extracted within 6 months from liver damage onset (n = 144), HEV antigen (Ag) and anti-HEV IgM antibodies were tested in duplicate by ELISA. In addition, RT-PCR was performed externally in eight patients. RESULTS: Out of 144 patients, 12 (8%) were positive for anti-HEV IgM, mean age was 61 years. Underlying hepatic diseases (OR = 23.4, P < .001) and AST peak >20 fold upper limit of normal (OR = 10.9, P = .002) were associated with the diagnosis of acute hepatitis E. The overall anti-HEV IgG seroprevalence rate was 35%, evenly distributed between patients with suspected DILI (34%), and controls (39%). CONCLUSIONS: HEV seroprevalence and acute hepatitis E rates are relatively high in Spain. A search for active HEV infection is therefore advised in patients assessed for suspicion of DILI, particularly in patients with underlying liver diseases and high transaminase levels.

Prevention and management of idiosyncratic drug-induced liver injury: Systematic review and meta-analysis of randomised clinical trials.

Conducting randomised clinical trials (RCTs) in idiosyncratic drug-induced liver injury (DILI) is challenging. This systematic review aims to summarise the design and findings of RCTs in the prevention and management of idiosyncratic DILI. A systematic literature search up to January 31st, 2020 was performed. Recognised scales were used to assess methodological bias and quality of the studies. Quantitative and qualitative analyses were performed. Heterogeneity was assessed with I2 statistic. Overall, 22 RCTs were included: 12 on prevention (n = 2,471 patients) and 10 in management (n = 797) of DILI/non-acetaminophen DILI-related acute liver failure (ALF). Silymarin (eight studies), bicyclol (four), magnesium isoglycyrrhizinate (three), N-acetylcysteine (three), tiopronin (one), L-carnitine (one), and traditional Chinese medicines (two) were tested in the intervention arm, while control arm mostly received standard supportive care or placebo. Main efficacy criteria in the prevention RCTs was DILI incidence or peak of liver enzymes value. In management RCTs, the efficacy parameter was usually 50 % decrease or normalisation of liver enzymes, or survival rate in DILI-related ALF patients. Overall, 15 trials described the randomisation method, eight were double-blind (n = 672) and nine had sample size estimation (n = 880). Four RCTs involving 377 patients used an intention-to-treat analysis. Based on the scarce number of trials available, tested agents showed limited efficacy in DILI prevention and management and a favourable safety profile. In conclusion, heterogeneity among studies in DILI case qualification and methodologic quality was evident, and the RCTs performed demonstrated limited efficacy of specific interventions. International research networks are needed to establish a framework on RCTs design and therapeutic endpoints.

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.

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.

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.

Assessment of Serious Acute and Chronic Idiosyncratic Drug-Induced Liver Injury in Clinical Practice.

Drug-induced liver injury (DILI) is the leading cause of acute liver failure (ALF) in developed countries. The extremely variable phenotype of DILI, both in presentation and in severity, is one of the distinctive characteristics of the disease and one of the major challenges that hepatologists face when assessing hepatotoxicity cases. A new Hy's law that more accurately predicts the risk of ALF related to DILI has been proposed and validated. Other prognostic scoring algorithms for the early identification of DILI patients who may go on to develop ALF have been developed as it is of most clinical relevance to stratify patients for closer monitoring. Recent data indicate that acute DILI often presents a more prolonged resolution or evolves into chronicity at a higher frequency than other forms of acute liver injury. Risk factors for chronicity, specific phenotypes, and histological features are discussed in this study. Biomarkers to predict DILI outcome are in need.

The influence of drug properties and host factors on delayed onset of symptoms in drug-induced liver injury.

BACKGROUND & AIMS: Most patients with drug-induced liver injury (DILI) manifest clinical symptoms while on therapy, while some patients manifest days or weeks after drug cessation (delayed onset). This challenges DILI causality assessment and diagnosis. Factors contributing to the delayed onset phenotype are currently unknown. We explored factors contributing to delayed onset of DILI by analysing culprit drug properties, host factors and their interactions in a large patient population from the Spanish DILI Registry. METHODS: Clinical information from 388 patients (69 presented delayed onset) and drug properties of 43 causative drugs (45 active ingredients) were analysed. A two-tier regression-based model was used to assess host/drug interactions affecting the probability of delayed onset. RESULTS: Antibacterial and anti-inflammatory drugs accounted for the delayed onset cases. Drug property of <50% hepatic metabolism (odds ratio [OR] 11.06, 95% confidence interval [95% CI]: 4.4-32.2, P = 0.0003), daily dose ≥1000 mg (OR: 2.77, 95% CI: 1.3-6.1, P = 0.0063) and the absence of pre-existing conditions in a patient (OR: 2.55, 95% CI: 1.3-4.9, P = 0.0043) were independently associated with delayed onset. The findings were consistent when externally validated using Latin American DILI Network cases (N = 131). Likewise, drug properties of mitochondrial liability and Pauling electronegativity were associated with delayed onset, but dependent on specific host factors such as age, sex and pre-existing cardiac diseases. CONCLUSIONS: This study demonstrated that delayed onset, a specific DILI phenotype, is explained by complex interactions among drug properties and host factors and provided mechanistic hypotheses for future studies. These findings can help improve the diagnostic capability and causality assessment.

Herbal and Dietary Supplement-Induced Liver Injuries in the Spanish DILI Registry.

BACKGROUND & AIMS: There have been increasing reports of liver injury associated with use of herbal and dietary supplements, likely due to easy access to these products and beliefs among consumers that they are safer or more effective than conventional medications. We aimed to evaluate clinical features and outcomes of patients with herbal and dietary supplement-induced liver injuries included in the Spanish DILI Registry. METHODS: We collected and analyzed data on demographic and clinical features, along with biochemical parameters, of 32 patients with herbal and dietary supplement-associated liver injury reported to the Spanish DILI registry from 1994 through 2016. We used analysis of variance to compare these data with those from cases of liver injury induced by conventional drugs or anabolic androgenic steroid-containing products. RESULTS: Herbal and dietary supplements were responsible for 4% (32 cases) of the 856 DILI cases in the registry; 20 cases of DILI (2%) were caused by anabolic androgenic steroids. Patients with herbal and dietary supplement-induced liver injury were a mean age of 48 years and 63% were female; they presented a mean level of alanine aminotransferase 37-fold the upper limit of normal, 28% had hypersensitivity features, and 78% had jaundice. Herbal and dietary supplement-induced liver injury progressed to acute liver failure in 6% of patients, compared with none of the cases of anabolic androgenic steroid-induced injury and 4% of cases of conventional drugs. Liver injury after repeat exposure to the same product that caused the first DILI episode occurred in 9% of patients with herbal and dietary supplement-induced liver injury vs none of the patients with anabolic androgenic steroid-induced injury and 6% of patients with liver injury from conventional drugs. CONCLUSION: In an analysis of cases of herbal and dietary supplement-induced liver injury in Spain, we found cases to be more frequent among young women than older patients or men, and to associate with hepatocellular injury and high levels of transaminases. Herbal and dietary supplement-induced liver injury is more severe than other types of DILI and re-exposure is more likely. Increasing awareness of the hepatoxic effects of herbal and dietary supplements could help physicians make earlier diagnoses and reduce the risk of serious liver damage.

Autoantibody presentation in drug-induced liver injury and idiopathic autoimmune hepatitis: the influence of human leucocyte antigen alleles.

OBJECTIVES: Positive autoantibody (AAB) titres are commonly encountered in autoimmune hepatitis (AIH) and in a proportion of drug-induced liver injury (DILI) patients. The underlying mechanism for selective AAB occurrence in DILI is unknown, but could be associated with variations in immune-associated genes. Hence, we aimed to analyse human leucocyte antigen (HLA) allele compositions in DILI with positive (+) and negative (-) AAB titres and in AIH patients. METHODS: High-resolution genotyping of HLA class I (A, B, C) and II (DRB1, DQB1) loci was performed on 207 DILI and 50 idiopathic AIH patients and compared with 885 healthy Spanish controls. RESULTS: Compared with controls, HLA-B*08:01 [44 vs. 9.7%, P=3.7E-13/corrected P-value (Pc)=1.0E-11], C*07:01 (46 vs. 24%, P=6.4E-04/Pc=0.012), DRB1*03:01 (58 vs. 21.5%, P=5.0E-09/Pc=1.0E-07) and DQB1*02:01 (56 vs. 22%, P=6.8E-08/Pc=9.0E-07) were significantly more frequent in AIH patients. The HLA-A*01:01 frequency was increased in the same population, but did not reach significance after Bonferroni's correction (34 vs. 19%, P=0.02/Pc=0.37). Fifty-eight of 207 DILI patients presented positive titres for at least one AAB (predominantly antinuclear antibody 76% and antismooth muscle antibody 28%). There was a tendency towards higher representation of DRB1*14:01 and DQB1*05:03 in DILI AAB+ compared with DILI AAB- (13.8 vs. 4.0%, P=0.02/Pc=0.5; 13.8 vs. 4.7%, P=0.04/Pc=0.5). CONCLUSION: The presence of HLA alleles B*08:01, C*07:01, DRB1*03:01, DQB1*02:01 and possibly A*01:01 enhances the risk of AIH (type 1) in Spanish patients. These alleles form part of the ancestral haplotype 8.1. HLA-DRB1*14:01 and DQB1*05:03 could potentially increase the risk of positive AAB (particularly antinuclear antibody) in Spanish DILI patients.

Definition and risk factors for chronicity following acute idiosyncratic drug-induced liver injury.

BACKGROUND & AIMS: Chronic outcome following acute idiosyncratic drug-induced liver injury (DILI) is not yet defined. This prospective, long-term follow-up study aimed to analyze time to liver enzyme resolutions to establish the best definition and risk factors of DILI chronicity. METHODS: 298 out of 850 patients in the Spanish DILI registry with no pre-existing disease affecting the liver and follow-up to resolution or ⩾1year were analyzed. Chronicity was defined as abnormal liver biochemistry, imaging test or histology one year after DILI recognition. RESULTS: Out of 298 patients enrolled 273 (92%) resolved ⩽1year from DILI recognition and 25 patients (8%) were chronic. Independent risk factors for chronicity were older age [OR: 1.06, p=0.011], dyslipidemia [OR: 4.26, p=0.04] and severe DILI [OR: 14.22, p=0.005]. Alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin (TB) median values were higher in the chronic group during follow-up. Values of ALP and TB >1.1 x upper limit of normal (xULN) and 2.8 xULN respectively, in the second month from DILI onset, were found to predict chronic DILI (p<0.001). Main drug classes involved in chronicity were statins (24%) and anti-infectives (24%). Histological examination in chronic patients demonstrated two cases with ductal lesion and seven with cirrhosis. CONCLUSIONS: One year is the best cut-off point to define chronic DILI or prolonged recovery, with risk factors being older age, dyslipidemia and severity of the acute episode. Statins are distinctly related to chronicity. ALP and TB values in the second month could help predict chronicity or very prolonged recovery. LAY SUMMARY: Drug-induced liver injury (DILI) patients who do not resolve their liver damage during the first year should be considered chronic DILI patients. Risk factors for DILI chronicity are older age, dyslipidemia and severity of the acute episode. Chronic DILI is not a very common condition; normally featuring mild liver profile abnormalities and not being an important clinical problem, with the exception of a small number of cases of early onset cirrhosis.