Drug-Induced Liver Injury in GI Practice

Clinical guidance for cannabidiol-associated hepatotoxicity: A narrative review

There is increasing evidence that cannabidiol (CBD) use is associated with clinically significant liver enzyme (LE) elevations and drug-induced liver injury (DILI). The proportion of LE elevations and DILI events reported in the literature meet the Council for International Organizations of Medical Sciences' (CIOMS) classification of a common adverse drug reaction. However, these potential adverse events are unknown to many clinicians and may be overlooked. The increasing use of CBD for both medical and non-medical use necessitates clear direction in the diagnosis and management of CBD-associated hepatotoxicity. To our knowledge, no such clinical guidance currently exists. For people presenting with elevated LEs, CBD use should be screened for and be considered in the differential diagnosis. This narrative review will provide clinicians with guidance in the prevention, detection, and management of CBD-related hepatotoxicity.

MetaLAB-HOI: Template standardization of health outcomes enable massive and accurate detection of adverse drug reactions from electronic health records

PURPOSE

This study aimed to advance the MetaLAB algorithm and verify its performance with multicenter data to effectively detect major adverse drug reactions (ADRs), including drug-induced liver injury.

METHODS

Based on MetaLAB, we created an optimal scenario for detecting ADRs by considering demographic and clinical records. MetaLAB-HOI was developed to identify ADR signals using common model-based multicenter electronic health record (EHR) data from the clinical health outcomes of interest (HOI) template and design for drug-exposed and nonexposed groups. In this study, we calculated the odds ratio of 101 drugs for HOI in Konyang University Hospital, Seoul National University Hospital, Chungbuk National University Hospital, and Seoul National University Bundang Hospital.

RESULTS

The overlapping drugs in four medical centers are amlodipine, aspirin, bisoprolol, carvedilol, clopidogrel, clozapine, digoxin, diltiazem, methotrexate, and rosuvastatin. We developed MetaLAB-HOI, an algorithm that can detect ADRs more efficiently using EHR. We compared the detection results of four medical centers, with drug-induced liver injuries as representative ADRs.

CONCLUSIONS

MetaLAB-HOI's strength lies in fully utilizing the patient's clinical information, such as prescription, procedure, and laboratory results, to detect ADR signals. Considering changes in the patient's condition over time, we created an algorithm based on a scenario that accounted for each drug exposure and onset period supervised by specialists for HOI. We determined that when a template capable of detecting ADR based on clinical evidence is developed and manualized, it can be applied in medical centers for new drugs with insufficient data.

Liver injury due to endothelin receptor antagonists: a real-world study based on post-marketing drug monitoring data

BACKGROUND

Liver injury is the hallmark adverse reaction of endothelin receptor antagonist (ERA). Since the first drug, bosentan has been widely used in clinical practice, hepatotoxicity has been accompanied by the history of ERA. The new ERA has been proven to have a lower liver risk but the current research findings are inconsistent. ERA-based targeted drug combinations are commonly used in the treatment of pulmonary arterial hypertension, where the risk of liver injury is difficult to estimate.

OBJECTIVES

This study aimed to compare the correlation between ERA and different ERA combination regimens with liver injury in the real world.

DESIGN

This is a retrospective study using data from the Adverse Event Reporting System (Food and Drug Administration AERS, FAERS).

METHODS

The study used proportional imbalance and Bayesian analysis to mine FAERS data from January 2004 to December 2022 to determine the association of three ERAs with liver injury and to further mine the risk of liver injury due to the combination of ERAs with other targeted drugs. In addition, we analyzed the onset time, mortality, and hospitalization rate of liver injury caused by different ERA combination regimens.

RESULTS

We screened out 3581 ERA-related liver injury events, of which bosentan (59.82%) had the largest number of cases. The patients with liver injury were mainly female (60.63%), and the age was concentrated between 61 and 75 years (26.75%). According to different signal mining methods, reporting odds ratio (ROR; 3.38, 95% confidence interval = 3.23-3.53), proportional reporting ratio (PRR; 3.22, χ2 = 37.84), Bayesian confidence propagation neural network (BCPNN; 1.68, 95% confidence interval = 1.61), multi-item gamma Poisson shrinker (MGPS; 3.21, 95% confidence interval = 3.09), bosentan had the strongest association with liver injury compared to ambrisentan and macitentan. Furthermore, bosentan + sildenafil [ROR (2.52, 95% confidence interval = 2.23-2.84), PRR (2.44, χ2 = 15.92), BCPNN (1.29, 95% confidence interval = 1.14), MGPS (2.44, 95% confidence interval = 2.21)], bosentan + epoprostenol [ROR (5.39, 95% confidence interval = 4.29-6.77), PRR (4.94, χ2 = 65.18), BCPNN (2.30, 95% confidence interval = 1.83), MGPS (4.94, 95% confidence interval = 4.08)], bosentan + iloprost [ROR (2.70, 95% confidence interval = 2.11-3.45), PRR (2.61, χ2 = 31.03), BCPNN (1.38, 95% confidence interval = 1.08), MGPS (2.61, 95% confidence interval = 2.12)] had a higher risk of liver injury caused by the three ERA combination regimens. The median time to onset of hepatotoxicity associated with all ERA combination regimens was 259 days (interquartile range: 58-716.5 days). Finally, the hospitalization rate for patients experiencing hepatotoxicity with ERA combination regimens was 47.86% and the mortality rate was 12.67%.

CONCLUSION

By mining the FAERS, we analyzed and compared the risk of liver injury related to different ERA and ERA combination regimens, and the onset time and adverse reaction outcomes of all ERA combination regimens. According to the results of the study, bosentan had the highest risk of liver injury and the combination regimens bosentan + sildenafil, bosentan + epoprostenol, and bosentan + iloprost had a stronger risk of liver injury. From the early stages of treatment, we need to regularly monitor the liver function of patients, especially for females and the elderly, and discontinue the suspected drug as soon as the liver injury occurs.

Strategies for mitigating adverse events related to selective RET inhibitors in patients with RET-altered cancers

The US Food and Drug Administration (FDA) approval of the selective RET inhibitors selpercatinib and pralsetinib has led to a paradigm change in the treatment of RET-altered lung and thyroid cancers through a higher response rate and a more tolerable safety and toxicity profile than multi-kinase inhibitors. Recently, selpercatinib has received a tissue-agnostic FDA approval for all RET-fusion-positive cancers, and pralsetinib has shown pan-cancer activity as well. Given the anticipated increase in the use of both drugs across multiple tumor types, it is crucial to recognize the possible side effects and approaches for their optimal management in order to maximize the clinical benefit for treated patients. In this review, we underscore potential toxicities associated with selective RET inhibitors and discuss strategies to mitigate them.

Concurrent administration of farnesol protects acetaminophen-induced acute hepatic necrosis in mice

Acetaminophen (APAP) is known to cause acute liver injury and acute liver failure in Western countries. This study investigates the protective role of farnesol (FAR) (C15 H26 O), a natural sesquiterpene alcohol in essential oils, against APAP-induced acute liver necrosis in mice. Mice were injected with a single dose of APAP (300 mg/kg) via an intraperitoneal route. Different groups of mice were concurrently treated with a single dose of FAR 25 mg/kg, FAR 50 mg/kg, and N-acetylcysteine. APAP administration caused a significant increase in transaminase activities and malondialdehyde (MDA) levels in the serum and liver tissue, respectively, with a concomitant decrease in intracellular antioxidants, including reduced glutathione (GSH) in the liver tissue. APAP intoxication upregulated proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1β (IL-1β), IL-6, nuclear factor-κB (NF-κB), and IκB kinase β in the liver tissue. FAR and N-acetylcysteine (NAC) administrations concurrently with APAP prevented serum transaminase increase in serum and MDA levels in the liver tissue. A high dose of FAR and NAC treatments significantly inhibited GSH and other antioxidant depletion. FAR and NAC treatments also downregulated the expression of proinflammatory markers. FAR treatments protects against APAP-induced acute liver injury and offers antioxidant and anti-inflammatory effects by inhibiting the NF-κB pathway involved in the transcription of genes responsible for inflammatory cytokine synthesis.

Autoimmune liver disease and multiple sclerosis: state of the art and future perspectives

Clinical observations suggest that the prevalence of autoimmune diseases is changing over time. Both autoimmune liver diseases and multiple sclerosis have shown a significant increase in the last decades. Although the coexistence of autoimmune diseases within individuals and families is a common phenomenon, the extent to which liver disease and multiple sclerosis co-occur is not clear. Case reports and few studies have reported the possible coexistence of multiple sclerosis with thyroid diseases, inflammatory bowel disease, psoriasis, and rheumatoid arthritis. It is unknown whether there is a definite association between multiple sclerosis and autoimmune liver diseases. We reviewed the literature to summarize the available studies on the association between different autoimmune liver diseases (autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis) and treated or untreated multiple sclerosis.

[Drug-induced liver injury: diagnosis of exclusion]

Drug-induced liver injury (DILI) is a relevant issue in clinical practice and is still a diagnosis of exclusion. Despite the low incidence in the general population, DILI is the cause of most cases of acute hepatic injury and has a mortality rate of up to 50%. Despite many reports in the medical literature about the DILI mechanisms, a clear causal relationship between them, drugs, and risk factors has not been established. Current clinical practice is based on a combination of a thorough study of a history of risk factors, the timing of drug and dietary supplements' administration, and the analysis of laboratory and instrumental tests. It aligns with the international criteria of the Rousell Uclaf Causality Assessment Method (RUCAM), which is considered one of the main diagnostic algorithms for DILI. The article addresses current DILI classification, risk factors, diagnostic algorithms, causalities, clinical evaluation, promising liver function biomarkers, and specific treatment.

The First Case of Daratumumab-Induced Fulminant Hepatic Failure

Drug-induced liver failure is a relatively uncommon condition with a vast spectrum of clinical manifestations, and it is a leading cause of acute hepatic failure in the United States. We describe the first case of fulminant hepatic failure induced by chemotherapeutic drug daratumumab, a common FDA-approved agent. A 77-year-old male, with a history of multiple myeloma, was admitted for left lower extremity cellulitis, two weeks after receiving his first intravenous infusion of daratumumab. He developed fulminant hepatic failure in the hospital a few days later. Despite multiple doses of N-acetylcysteine, his liver function continued to decline, and he expired shortly after.

The exposome and liver disease - how environmental factors affect liver health

Since the initial development of the exposome concept, much effort has been devoted to the characterisation of the exposome through analytical, epidemiological, and toxicological/mechanistic studies. There is now an urgent need to link the exposome to human diseases and to include exposomics in the characterisation of environment-linked pathologies together with genomics and other omics. Liver diseases are particularly well suited for such studies since major functions of the liver include the detection, detoxification, and elimination of xenobiotics, as well as inflammatory responses. It is well known that several liver diseases are associated with i) addictive behaviours such as alcohol consumption, smoking, and to a certain extent dietary imbalance and obesity, ii) viral and parasitic infections, and iii) exposure to toxins and occupational chemicals. Recent studies indicate that environmental exposures are also significantly associated with liver diseases, and these include air pollution (particulate matter and volatile chemicals), contaminants such as polyaromatic hydrocarbons, bisphenol A and per-and poly-fluorinated substances, and physical stressors such as radiation. Furthermore, microbial metabolites and the "gut-liver" axis play a major role in liver diseases. Exposomics is poised to play a major role in the field of liver pathology. Methodological advances such as the exposomics-metabolomics framework, the determination of risk factors' genomic and epigenomic signatures, and cross-species biological pathway analysis should further delineate the impact of the exposome on the liver, opening the way for improved prevention, as well as the identification of new biomarkers of exposure and effects, and additional therapeutic targets.

Comparing Intravenous Labetalol and Intravenous Hydralazine for Managing Severe Gestational Hypertension

Background Hypertensive disorders of pregnancy are the leading causes of both maternal morbidity and maternal mortality. Hypertensive disorders are acute obstetric emergencies, which refer to various life-threatening medical challenges known to develop during pregnancy, labor, and delivery, requiring urgent attention to reduce blood pressure (BP) for the benefit of the affected mothers and infants. Hydralazine and labetalol have been widely used as the first-line medications in the management of severe hypertension during pregnancy. However, the choice between these two drugs lacks clear evidence regarding their safety and superiority. Several studies have attempted to study intravenous (IV) labetalol versus hydralazine, but very few such comparison studies have been conducted in Africa.  Objective To compare the effectiveness of IV labetalol and IV hydralazine in reducing systolic and diastolic BP in pregnant women with severe hypertension. Also, to determine the time required for hydralazine and labetalol to lower BP to ≤150/100 mmHg, the number of doses needed for each drug, and evaluating maternal and perinatal outcomes. Study design This study employed an open-label randomized clinical trial design conducted in the labor, delivery, and antenatal ward of the Central and Stella Obasanjo Hospital in Benin City. A total of 120 women with severe pregnancy-induced hypertension were randomly assigned to two groups: Group X, consisting of 60 pregnant women, received IV hydralazine at a slow rate of 5 mg for five minutes, repeated every 20 minutes (maximum of five doses) until a blood pressure of ≤150/100 mmHg was achieved. Group Y, also consisting of 60 pregnant women, received IV labetalol in escalating doses of 25, 50, 75, 75, and 75 mg (maximum of 300 mg) every 20 minutes until the blood pressure reached ≤150/100 mmHg. Statistical analysis was performed using SPSS version 23 (IBM Inc., Armonk, New York). Result IV hydralazine achieved the target BP in an average time of 45.80 +/- 25.17 minutes, while IV labetalol took an average of 72.67 +/- 41.80 minutes (p=0.001). The number of doses required to reach the target BP differed significantly between the two drugs. Hydralazine required an average of 1.72 +/- 0.904 doses, whereas labetalol required an average of 3.72 +/- 1.782 doses (p=0.0001). While 45% of women in the hydralazine group attained the target BP with a single dose of hydralazine, only 31.1% of women in the labetalol group were able to attain the target BP with a single dose of labetalol (p=0.02). Overall, target BP was achieved in 55 out of 60 women (91.7%) who were randomized to receive IV hydralazine, whereas 45 out of 60 women (75%) who received IV labetalol achieved the target blood pressure. While hydralazine demonstrated more favorable results in terms of achieving target blood pressure, there were higher incidences of maternal adverse effects in the hydralazine group compared to the labetalol group. However, these adverse effects were not severe enough to warrant discontinuation of the medication. Conclusion IV hydralazine showed faster achievement of the target BP and a lower number of doses required compared to IV labetalol. Additionally, a higher percentage of women in the hydralazine group achieved the target BP with a single dose. However, there were more maternal adverse effects associated with hydralazine, although they were not severe. Perinatal outcomes did not differ significantly between the two groups.

Protective Effects of Apamin on Acetaminophen-Induced Hepatotoxicity in Mice

Acetaminophen (APAP) overdose can cause severe liver damage, but therapeutic options are limited. Apamin is a natural peptide present in bee venom and has antioxidant and anti-inflammatory properties. Accumulating evidence suggests that apamin has favorable actions in rodent models of inflammatory disorders. Here, we examined the effect of apamin on APAP-evoked hepatotoxicity. Intraperitoneal administration of apamin (0.1 mg/kg) alleviated histological abnormalities and reduced serum levels of liver enzymes in mice injected with APAP. Apamin inhibited oxidative stress through an increase in the amount of glutathione and activation of the antioxidant system. Apamin also attenuated apoptosis with inhibition of caspase-3 activation. Moreover, apamin reduced serum and hepatic levels of cytokines in APAP-injected mice. These effects were accompanied by suppression of NF-κB activation. Furthermore, apamin inhibited chemokine expression and inflammatory cell infiltration. Our results suggest that apamin dampens APAP-evoked hepatotoxicity through inhibiting oxidative stress, apoptosis, and inflammation.

Recent progress in the development of fluorescent probes for imaging pathological oxidative stress

Oxidative stress is closely related to the physiopathology of numerous diseases. Reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive sulfur species (RSS) are direct participants and important biomarkers of oxidative stress. A comprehensive understanding of their changes can help us evaluate disease pathogenesis and progression and facilitate early diagnosis and drug development. In recent years, fluorescent probes have been developed for real-time monitoring of ROS, RNS and RSS levels in vitro and in vivo. In this review, conventional design strategies of fluorescent probes for ROS, RNS, and RSS detection are discussed from three aspects: fluorophores, linkers, and recognition groups. We introduce representative fluorescent probes for ROS, RNS, and RSS detection in cells, physiological/pathological processes (e.g., Inflammation, Drug Induced Organ Injury and Ischemia/Reperfusion Injury etc.), and specific diseases (e.g., neurodegenerative diseases, epilepsy, depression, diabetes and cancer, etc.). We then highlight the achievements, current challenges, and prospects for fluorescent probes in the pathophysiology of oxidative stress-related diseases.

Probable Enoxaparin-Induced Liver Injury in a Young Patient: A Case Report of a Diagnostic Challenge

Low molecular weight heparin (LMWH) is associated with elevated liver enzyme levels in a small percentage of patients. Elevations more than five times the upper limit of normal are uncommon and have been noted to primarily occur in patients receiving higher doses. The literature reports mild, primarily asymptomatic cases, with adverse effects at higher therapeutic doses. We report the case of a 27-year-old woman who developed drug-induced liver injury (DILI) while receiving enoxaparin during admission for a loculated pleural effusion secondary to pulmonary tuberculosis. The Roussel Uclaf Causality Assessment Method (RUCAM) score delineated enoxaparin as the likely cause.

Retracted and Republished from: "Gut Microbiota Mediates the Therapeutic Effect of Monoclonal Anti-TLR4 Antibody on Acetaminophen-Induced Acute Liver Injury in Mice"

Acetaminophen (APAP) overdose is one of the most common causes of acute liver injury (ALI) in Western countries. Many studies have shown that the gut microbiota plays an important role in liver injury. Currently, the only approved treatment for APAP-induced ALI is N-acetylcysteine; therefore, it is essential to develop new therapeutic agents and explore the underlying mechanisms. We developed a novel monoclonal anti-Toll-like receptor 4 (TLR4) antibody (ATAB) and hypothesized that it has therapeutic effects on APAP-induced ALI and that the gut microbiota may be involved in the underlying mechanism of ATAB treatment. Male C57BL/6 mice were treated with APAP and ATAB, which produced a therapeutic effect on ALI and altered the members of the gut microbiota and their metabolic pathways, such as Roseburia, Lactobacillus, Akkermansia, and the fatty acid pathway, etc. Furthermore, we verified that purified short-chain fatty acids (SCFAs) could alleviate ALI. Moreover, a separate group of mice that received feces from the ATAB group showed less severe liver injury than mice that received feces from the APAP group. ATAB therapy also improved gut barrier functions in mice and reduced the expression of the protein zonulin. Our results revealed that the gut microbiota plays an important role in the therapeutic effect of ATAB on APAP-induced ALI. IMPORTANCE In this study, we found that a monoclonal anti-Toll-like receptor 4 antibody can alleviate APAP-induced acute liver injury through changes in the gut microbiota, metabolic pathways, and gut barrier function. This work suggested that the gut microbiota can be a therapeutic target of APAP-induced acute liver injury, and we performed foundation for further research.

Cannabidiol-associated hepatotoxicity: A systematic review and meta-analysis

BACKGROUND

Findings of liver enzyme elevations in recent cannabidiol studies have raised concerns over liver safety. This study aimed to determine the association between cannabidiol use, liver enzyme elevation, and drug-induced liver injury (DILI).

METHODS

In this systematic review and meta-analysis, a search of EMBASE, CENTRAL, CINAHL, Clinicaltrials.gov, Medline, medRxiv, and Web of Science of records up to February 2022 was conducted. Clinical trials initiating daily cannabidiol treatment with serial liver enzyme measures were included. The proportion of liver enzyme elevations and DILI were independently extracted from published reports. Pooled proportions and probability meta-analyses were conducted.

RESULTS

Cannabidiol use was associated with an increased probability of liver enzyme elevation (N = 12 trials, n = 1229; OR = 5.85 95% CI = 3.84-8.92, p < 0.001) and DILI (N = 12 trials, n = 1229; OR = 4.82 95% CI = 2.46-9.45, p < 0.001) compared to placebo controls. In participants taking cannabidiol (N = 28 trials, n = 1533), the pooled proportion of liver enzyme elevations was 0.074 (95% CI 0.0448-0.1212), and DILI was 0.0296 (95% CI 0.0136-0.0631). High-dose CBD (≥1000 mg/day or ≥20 mg/kg/day) and concomitant antiepileptic drug use were identified as risk factors. No cases were reported in adults using cannabidiol doses <300 mg/day. No cases of severe DILI were reported.

CONCLUSIONS

Cannabidiol-associated liver enzyme elevations and DILI meet the criteria of common adverse drug events. Clinicians are encouraged to screen for cannabidiol use and monitor liver function in patients at increased risk.

Nonalcoholic Fatty Liver Disease Is a Risk Factor for Thiopurine Hepatotoxicity in Crohn's Disease

Background

Patients with Crohn's disease (CD) are predisposed to nonalcoholic fatty liver disease (NAFLD). CD management often includes thiopurines which can promote hepatotoxicity. We aimed to identify the role of NAFLD on the risk of developing liver injury from thiopurines in CD.

Methods

In this prospective cohort analysis, CD patients at a single center were recruited 6/2017-5/2018. Patients with alternative liver diseases were excluded. The primary outcome was time to elevation of liver enzymes. Patients underwent MRI with assessment of proton density fat fraction (PDFF) on enrollment, where NAFLD was defined as PDFF >5.5%. Statistical analysis was performed using a Cox-proportional hazards model.

Results

Of the 311 CD patients studied, 116 (37%) were treated with thiopurines, 54 (47%) of which were found to have NAFLD. At follow-up, there were 44 total cases of elevated liver enzymes in those treated with thiopurines. Multivariable analysis demonstrated that NAFLD was a predictor of elevated liver enzymes in patients with CD treated with thiopurines (HR 3.0, 95% CI 1.2-7.3, P = .018) independent of age, body mass index, hypertension, and type 2 diabetes. Steatosis severity by PDFF positively correlated with peak alanine aminotransferase (ALT) at follow-up. Kaplan-Meier analysis demonstrated poorer complication-free survival (log-rank 13.1, P < .001).

Conclusions

NAFLD at baseline is a risk factor for thiopurine-induced hepatotoxicity in patients with CD. The degree of liver fat positively correlated with the degree of ALT elevation. These data suggest that evaluation for hepatic steatosis be considered in patients with liver enzyme elevations with thiopurine therapy.

COVID-19-related liver injury: Focus on genetic and drug-induced perspectives

BACKGROUND

Empirical use of potentially hepatotoxic drugs in the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is considered as one of the major etiopathogenetic factors for liver injury. Recent evidence has shown that an underlying genetic factor may also occur. Hence, it is important to understand the host genetics and iatrogenic-based mechanisms for liver dysfunction to make timely remedial measures.

AIM

To investigate drug-induced and genetic perspectives for the development of coronavirus disease 2019 (COVID-19)-related liver injury.

METHODS

Reference Citation Analysis, PubMed, Google Scholar and China National Knowledge Infrastructure were searched by employing the relevant MeSH keywords and pertaining data of the duration, site and type of study, sample size with any subgroups and drug-induced liver injury outcome. Genetic aspects were extracted from the most current pertinent publications.

RESULTS

In all studies, the hepatic specific aminotransferase and other biochemical indices were more than their prescribed upper normal limit in COVID-19 patients and were found to be significantly related with the gravity of disease, hospital stay, number of COVID-19 treatment drugs and worse clinical outcomes. In addition, membrane bound O-acyltransferase domain containing 7 rs641738, rs11385942 G>GA at chromosome 3 gene cluster and rs657152 C>A at ABO blood locus was significantly associated with severity of livery injury in admitted SARS-CoV-2 patients.

CONCLUSION

Hepatic dysfunction in SARS-CoV-2 infection could be the result of individual drugs or due to drug-drug interactions and may be in a subset of patients with a genetic propensity. Thus, serial estimation of hepatic indices in hospitalized SARS-CoV-2 patients should be done to make timely corrective actions for iatrogenic causes to avoid clinical deterioration. Additional molecular and translational research is warranted in this regard.

Discontinuation of immunosuppression in patients with immune-mediated drug-induced liver injury or idiopathic autoimmune hepatitis: A case-control study

Background and Aim

Drug-induced liver injury (DILI) may present with autoimmune features and require immunosuppressive therapy (IST) to reach biochemical response. Discontinuation of IST without hepatitis relapse may be more frequent in these patients as compared to patients with classical autoimmune hepatitis (AIH). We aimed to determine baseline characteristics and outcome of patients with immune-mediated drug induced liver injury (IMDILI) with particular emphasis on IST during follow-up.

Methods

We performed a single-center retrospective study of consecutive patients presenting at a tertiary care center between January 2005 and December 2019 either with IMDILI or with classical AIH, for whom full baseline characteristics and a close follow-up were available over a 12-month period.

Results

Overall, 31 patients (IMDILI n = 16, mean age 59 [34-74] years; AIH n = 15, mean age 47 [15-61] years) were included, showing similar biochemical, serological, and histological characteristics. Incriminating drugs in IMDILI patients were mostly represented by nonsteroidal antiinflammatory drugs and sartans. Initial corticosteroids combined with IST led to biochemical response in all patients. Compared to idiopathic AIH, more patients with IMDILI were weaned off corticosteroids at the end of follow-up (11/16 [68.7%] vs 4/15 [26.6%], P < 0.02). At 1 year of follow-up, more patients in the IMDILI group compared to the classical AIH group were off any type of IST (13/16 [81%] vs 15/15 [100%], P = 0.08).

Conclusions

Although presenting with similar baseline biochemical and histological characteristics as idiopathic AIH, patients with IMDILI may not require long-term IST.

Role of silymarin as antioxidant in clinical management of chronic liver diseases: a narrative review

Chronic liver disease (CLD), manifested as hepatic injury, is a major cause of global morbidity and mortality. CLD progresses to fibrosis, cirrhosis, and-ultimately-hepatocellular carcinoma (HCC) if left untreated. The different phenotypes of CLD based on their respective clinical features and causative agents include alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), metabolic-associated fatty liver disease (MAFLD), and drug-induced liver injury (DILI). The preferred treatment modality for CLD includes lifestyle modification and diet, along with limited pharmacological agents for symptomatic treatment. Moreover, oxidative stress (OS) is an important pathological mechanism underlying all CLD phenotypes; hence, the use of antioxidants to manage the disease is justified. Based on available clinical evidence, silymarin can be utilized as a hepatoprotective agent, given its potent antioxidant, antifibrotic, and anti-inflammatory properties. The role of silymarin in suppressing OS has been well established, and therefore silymarin is recommended for use in ALD and NAFLD in the guidelines approved by the Russian Medical Scientific Society of Therapists and the Gastroenterology Scientific Society of Russia. However, to discuss the positioning of the original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies, an expert panel of international and Russian medical professionals was convened on 11 November 2020. The panel reviewed approaches for the prevention and treatment of OS, existing guidelines for patient management for CLD, and available evidence on the effectiveness of silymarin in reducing OS, fibrosis, and hepatic inflammation and presented in the form of a narrative review. Key messagesAn expert panel of international and Russian medical professionals reviewed existing guidelines for ALD, NAFLD, MAFLD, and DILI to establish consensus recommendations that oxidative stress is the common pathophysiological mechanism underlying these conditions.The panel also discussed the positioning of original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies.The panel reviewed the effectiveness of 140 mg original silymarin three times a day in reducing oxidative stress in chronic liver diseases such as ALD, NAFLD, MAFLD, and DILI.

Severe Cholestatic Drug-Induced Liver Injury With Cephalosporin Use

Drug-induced liver injury (DILI) is a phenomenon that occurs with nearly all classes of medications. Cholestatic DILI represents a fraction of these cases and can present as bland cholestasis, cholestatic hepatitis, secondary sclerosis cholangitis, and vanishing bile duct syndrome. Risk factors have been identified for cholestatic DILI, including older age, genetic determinants, and certain medications such as amoxicillin-clavulanate. Here, we describe a complicated case of severe cholestatic DILI secondary to cephalosporin use. A 27-year-old female presented to the hospital initially with fever and abdominal pain for four weeks after an emergency C-section for pre-eclampsia and hemolysis, elevated liver enzymes, lowered platelets (HELLP) syndrome. She was found to have a retroperitoneal abscess and underwent bilateral drain placement. She was initially started on cefazolin, and then coverage was broadened to cefepime. Shortly after, alkaline phosphatase (ALP) rose and peaked at 3498 IU/L, with aspartate aminotransferase (AST) and alanine transaminase (ALT) elevated at 274 IU/L and 122 IU/L, respectively. Extensive testing for secondary causes and a liver biopsy were consistent with DILI. Liver enzymes down-trended with the cessation of cefepime. This case report highlights that prompt recognition of the culprit medication is paramount to recovering normal liver function.

Drug-induced Liver Injury in Pediatrics

Drug-induced liver injury (DILI) is a rare, underdiagnosed cause of liver disease in children. The incidence of DILI in the pediatric population is unknown but it represents around 10% of all DILI cases. The most common hepatotoxic drugs in children are antibiotics and antiepileptics. DILI is classified as intrinsic or idiosyncratic and it presents mostly with 2 patterns of injury: hepatocellular or cholestatic. Diagnosis can be done with help of the Roussel Uclaf Causality Assessment Method (RUCAM) casualty assessment. The mainstay of treatment is prompt withdrawal of the suspect drug.

Syringic acid and silymarin concurrent administration inhibits sodium valproate-induced liver injury in rats

Sodium valproate (SV) is a well-known anti-epileptic drug, also used to control convulsions, bipolar disorders and migraines. SV has been shown to induce liver toxicity in clinical subjects. Syringic acid (SA), a natural polyphenolic compound has potential antioxidant, anti-inflammatory and several beneficial effects. Therefore, in this study, we evaluated hepatoprotective effect of SA against SV-induced liver injury in rats. Wistar rats were treated with SV orally at a dose of 500 mg/kg, once daily, for 14 days. Another three groups of rats were administered with SV and concurrently treated with SA (40 and 80 mg/kg) and silymarin (SIL) (100 mg/kg) for 14 days. SV administration for 14 days caused significant (p < .001) elevation of liver transaminases and ALP in serum. Liver MDA level was significantly (p < .001) increased with a concomitant decrease (p < .001) in enzymic antioxidants activities in SV administered rats. SV administration also caused the upregulation of proinflammatory markers such as tumor necrosis factor α, c-Jun N-terminal kinase, nuclear factor kappa B, cyclooxygenase-2 and Interleukin 6 expressions in liver tissue. Histopathological studies also revealed the presence of inflammatory cell infiltration and hepatocellular necrosis upon SV administration. At both doses, concurrent administration of SA and SIL significantly (p < .001) inhibited the liver transaminase activities in serum, oxidative stress, and proinflammatory markers expression in liver tissue. Our current results suggest that SA can be a promising herbal drug that can inhibit SV-induced hepatotoxicity when administered together due its potential anti-inflammatory effects.

The Hepatoprotective and Hepatotoxic Roles of Sex and Sex-Related Hormones

Most liver diseases, including acute liver injury, drug-induced liver injury, viral hepatitis, metabolic liver diseases, and end-stage liver diseases, are strongly linked with hormonal influences. Thus, delineating the clinical manifestation and underlying mechanisms of the “sexual dimorphism” is critical for providing hints for the prevention, management, and treatment of those diseases. Whether the sex hormones (androgen, estrogen, and progesterone) and sex-related hormones (gonadotrophin-releasing hormone, luteinizing hormone, follicle-stimulating hormone, and prolactin) play protective or toxic roles in the liver depends on the biological sex, disease stage, precipitating factor, and even the psychiatric status. Lifestyle factors, such as obesity, alcohol drinking, and smoking, also drastically affect the involving mechanisms of those hormones in liver diseases. Hormones deliver their hepatic regulatory signals primarily via classical and non-classical receptors in different liver cell types. Exogenous sex/sex-related hormone therapy may serve as a novel strategy for metabolic liver disease, cirrhosis, and liver cancer. However, the undesired hormone-induced liver injury should be carefully studied in pre-clinical models and monitored in clinical applications. This issue is particularly important for menopause females with hormone replacement therapy (HRT) and transgender populations who want to receive gender-affirming hormone therapy (GAHT). In conclusion, basic and clinical studies are warranted to depict the detailed hepatoprotective and hepatotoxic mechanisms of sex/sex-related hormones in liver disease. Prolactin holds a promising perspective in treating metabolic and advanced liver diseases.

Gut Microbiota Mediates the Therapeutic Effect of Monoclonal Anti-TLR4 Antibody on Acetaminophen-Induced Acute Liver Injury in Mice

Acetaminophen (APAP) overdose is one of the most common causes of acute liver injury (ALI) in Western countries. Many studies show that the gut microbiota plays an important role in liver injury. Currently, the only approved treatment for APAP-induced ALI is N-acetylcysteine; therefore, it is essential to develop new therapeutic agents and explore the underlying mechanisms. We developed a novel monoclonal anti-Toll-like receptor 4 (TLR4) antibody (ATAB) and hypothesized that it has therapeutic effects on APAP-induced ALI and that gut microbiota may be involved in the underlying mechanism of ATAB treatment. Male C57BL/6 mice were treated with APAP and ATAB, which produced a therapeutic effect on ALI and altered the gut microbiota and their metabolic pathway, such as Roseburia, Lactobacillus, Akkermansia, and the fatty acid pathway, etc. Furthermore, we verified that purified short-chain fatty acids (SCFAs) could alleviate ALI. Moreover, a separate group of mice that received feces from the ATAB group showed less severe liver injury compared with the mice receiving feces from the APAP group. ATAB therapy also improved the gut barrier functions in mice and reduced the expression of protein zonulin. Our results revealed that gut microbiota plays an important role in the therapeutic effect of ATAB on APAP-induced ALI. IMPORTANCE In this study, we found the monoclonal anti-Toll-like receptor 4 antibody can alleviate APAP-induced acute liver injury through the change of the gut microbiota, metabolic pathways, and gut barrier function. This work suggested the gut microbiota can be the therapeutic target of the APAP-induced acute liver injury, and we performed the fundamental research for further research.

The Potential Role of Metabolomics in Drug-Induced Liver Injury (DILI) Assessment

Drug-induced liver injury (DILI) is one of the most frequent adverse clinical reactions and a relevant cause of morbidity and mortality. Hepatotoxicity is among the major reasons for drug withdrawal during post-market and late development stages, representing a major concern to the pharmaceutical industry. The current biochemical parameters for the detection of DILI are based on enzymes (alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP)) and bilirubin serum levels that are not specific of DILI and therefore there is an increasing interest on novel, specific, DILI biomarkers discovery. Metabolomics has emerged as a tool with a great potential for biomarker discovery, especially in disease diagnosis, and assessment of drug toxicity or efficacy. This review summarizes the multistep approaches in DILI biomarker research and discovery based on metabolomics and the principal outcomes from the research performed in this field. For that purpose, we have reviewed the recent scientific literature from PubMed, Web of Science, EMBASE, and PubTator using the terms “metabolomics”, “DILI”, and “humans”. Despite the undoubted contribution of metabolomics to our understanding of the underlying mechanisms of DILI and the identification of promising novel metabolite biomarkers, there are still some inconsistencies and limitations that hinder the translation of these research findings into general clinical practice, probably due to the variability of the methods used as well to the different mechanisms elicited by the DILI causing agent.

Garcinia cambogia—A Supplement-Related Liver Injury

Drug-induced liver injury, and specifically supplement-related liver injury, accounts for an increasing proportion of acute liver injury cases. We present the case of acute liver injury due to a Garcinia cambogia-containing weight-loss supplement not previously associated with liver injury. Identifying supplements as a potential cause is a key to managing acute liver injury of uncertain etiology.

Liver Injury in Patients Hospitalized for COVID-19: Possible Role of Therapy

Patients with COVID-19 show a high prevalence of liver injury. The pattern of this liver damage is still not fully understood. Different etiopathogenetic factors may concur; from a direct cytopathic effect, once the virus binds to the ACE-2 receptors, to the immune-mediated collateral damage, due to cytokine storm. The presence of pre-existing chronic liver disease is a contributing factor for acute organ damage during SARS-CoV2 infection. Last but not least, treatments probably play a role, also, in determining hepatotoxicity: many of the drugs we have used or are still using to treat COVID-19, combined with non-invasive ventilation, are known to sometimes determine acute liver injury. Although liver damage associated with COVID-19 is often transient and can resolve without any special treatment, it is important to understand the underlying mechanisms, particularly to better treat its more severe forms.

Specificities of lipotoxicity of free fatty acids and cytokine profile in patients with chronic diffuse liver diseases

Non-alcoholic fatty liver disease is an important cause of global liver disease characterized by diffuse hepatocytes with hepatocellular ballooning, intrahepatic inflammation and progressive fibrosis. A relevant task is the study of the relationship between content of free fatty acids and serum cytokine profile in patients with chronic diffuse liver diseases. A total of 74 people with chronic diffuse liver diseases were examined, including 32 patients with non-alcoholic fatty liver disease, 22 patients with alcoholic liver disease, 20 patients with toxic hepatitis. Chromatographic examination of free fatty acids (FFA) in blood serum was carried out using a Chromatek-Crystal 5000 gas chromatography system. Patients with chronic diffuse liver diseases had a significant increase in the level of unsaturated free fatty acids (USFA) in cases of toxic hepatitis (by 2.92 times, P > 0.05) and a decrease in the level of saturated free fatty acids (SFA) in cases of non-alcoholic fatty liver disease (by 1.52 times, P > 0.05) compared with the control group; the balance between omega-6 and omega-3 PUFA significantly changed due to increase in linoleic acid in patients with alcoholic liver disease and toxic hepatitis (by 1.91 and 2.11 times, respectively) and arachidonic acid in patients with toxic hepatitis (by 1.78 times). The level of interleukin (IL)-6, IL-10, tumor necrosis factor alpha (TNF-α) were determined. In patients suffering chronic diffuse liver diseases there were multidirectional changes in the composition of free fatty acids of blood serum: a significant increase in the level of USFA, levels ІL-6 in toxic hepatitis; a decrease in the level of SFA, levels ІL-6 and TNF-α during non-alcoholic fatty liver disease; increased TNF-α production, ІL-6 during alcoholic liver disease compared with the control group. Significant change occurred in the balance between omega-6 and omega-3 PUFA due to increase in linoleic acid in cases of alcoholic liver disease and toxic hepatitis and arachidonic acid in cases of toxic hepatitis. The revealed correlations support the hypothesis that inflammation and lipotoxicity of FFA of blood serum contribute to the development and progression of structural changes in the liver. However, the pathomechanism of lipid metabolism and cytokine regulation with different etiological factors have their own characteristics, which should be taken into account when treating patients of these groups. Prospects for further research: these parameters may be used for serologic biomarkers of liver disease and development and implementation of the ratio between FFA and cytokines for the differential diagnosis of chronic diffuse liver disease in medical practice.

Drug-Induced Liver Injury Induced by Bioflavonoids

Drug-induced liver injury (DILI) is a relatively rare disease with a vast spectre of clinical manifestations. Its diagnosis is based on the exclusion of other causes of liver disease. The identification of a causal agent is based on the temporal relation between the symptoms and their resolution after stopping the suspected drug. Many drugs have been described as causative agents of DILI; however, bioflavonoids have never been implied with an idiosyncratic DILI in the literature.

An Activatable Probe with Aggregation-Induced Emission for Detecting and Imaging Herbal Medicine Induced Liver Injury with Optoacoustic Imaging and NIR-II Fluorescence Imaging

Whilte herbal medicines are widely used for health promotion and therapy for chronic conditions, inappropriate use of them may cause adverse effects like liver injury, and accurately evaluating their hepatotoxicity is of great significance for public health. Herein, an activatable probe QY-N for diagnosing herbal-medicine-induced liver injury by detecting hepatic NO with NIR-II fluorescence and multispectral optoacoustic tomography (MSOT) imaging is demonstrated. The probe includes a bismethoxyphenyl-amine-containing dihydroxanthene serving as electron donor, a quinolinium as electron acceptor, and a butylamine as recognition group and fluorescence quencher. The hepatic level of NO reacts with butylamine, thereby generating the activated probe QY-NO which exhibits a red-shifted absorption band (700-850 nm) for optoacoustic imaging and generates strong emission (910-1110 nm) for NIR-II fluorescence imaging. QY-NO is aggregation-induced-emission (AIE) active, which ensures strong emission in aggregated state. QY-N is utilized in the triptolide-induced liver injury mouse model, and experimental results demonstrate the QY-N can be activated by hepatic NO and thus be used in detecting herbal-medicine-induced liver injury. The temporal and spatial information provided by three-dimensional MSOT images well delineates the site and size of liver injury. Moreover, QY-N has also been employed to monitor rehabilitation of liver injury during treatment process.

Rhabdomyolysis due to rosuvastatin in a patient with ROHHAD syndrome

We report a 13-year-old female with rapid-onset obesity, hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome, panhypopituitarism, dyslipidemia, type 2 diabetes mellitus, and nonalcoholic fatty liver disease, who developed rhabdomyolysis and acute kidney injury, two weeks after switching from lovastatin to rosuvastatin. She had been on lovastatin for eight years without any adverse effects.

Hydralazine-induced liver injury: a review and discussion

Hydralazine is a commonly prescribed antihypertensive agent. Some of its labelled adverse reactions include lupus-like syndrome, tachycardia, headache and fever. Despite its well-known side effects, little is known about hydralazine's hepatotoxic effects. We report the case of a 54-year-old female patient who was started on hydralazine for hypertension management but later presented with hydralazine-induced liver injury. Her initial presentation consisted of non-specific symptoms and a hepatocellular injury pattern. Liver biopsy revealed hepatic steatosis. Three weeks after discontinuation of hydralazine, the patient's liver enzymes normalised, and her symptoms resolved. Few studies have examined the incidence and mechanism by which hydralazine induces a liver injury pattern. With this case, we review the literature, the pathogenesis involved and the eventual management of hydralazine-induced liver injury. We propose close monitoring of liver enzymes for patients on hydralazine throughout their treatment course.

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.

The Need for Alternatives to Liver Biopsies: Non-Invasive Analytics and Diagnostics

Histology remains essential for the diagnosis and management of many disorders affecting the liver. However, the biopsy procedure itself is associated with a low risk of harm to the patient and cost to the health services; samples may not be adequate and are subject to sampling variation. Furthermore, interpretation often depends on the skill of the pathologist. Increasingly, new techniques are becoming available that are altering the indications for liver biopsy. Many diseases of the liver can be diagnosed and managed using serological and radiological techniques; the degree of fibrosis and fat can often be assessed by serological or imaging techniques and the nature of space occupying lesions defined by serology, imaging and use of liquid biopsy. However, these techniques, too, are subject to limitations: sensitivity and specificity is not always adequate for diagnosis or management; some techniques are expensive and often also require expert interpretation. Although there may be less need for liver biopsy today, histology remains the gold standard as well as an essential tool for the diagnosis and management of many conditions, especially where there are multiple pathologies, or where a diagnosis cannot or has not been made by alternative approaches. Until less invasive techniques become more reliable and accessible, liver histology will remain a key investigation.

Statin use in patients with elevated serum hepatic transaminases at baseline: A meta-analysis

AIMS

Clinical trials showed that statin therapy decreased cardiovascular events without significantly raising the level of transaminases. However, the information in subjects with altered liver test at baseline is more limited. The objectives of this meta-analysis were to analyze the liver safety and cardiovascular benefit when using a statin-based lipid-lowering treatment compared to a less intensive treatment or placebo, in subjects with abnormal liver tests at baseline.

DATA SYNTHESIS

We performed a meta-analysis including randomized trials of statin-based lipid-lowering therapy versus less intensive lipid-lowering therapy or placebo, reporting worsening hepatic test (>3 ULN) and cardiovascular events in patients with abnormal liver tests at baseline. The random-effects model was performed. This meta-analysis was performed according to PRISMA guidelines. Five eligible trials, including 2548 patients were identified and considered eligible for the analyses. A more intensive statin-based lipid-lowering therapy were associated with a similar occurrence of serious alteration of liver tests (OR: 0.90, 95% confidence interval: 0.21-3.99; I²: 64%) compared to less intensive or placebo treatments. Likewise, more intensive lipid-lowering strategies were associated with a significant reduction in major cardiovascular events (OR: 0.34, 95% confidence interval: 0.17-0.70; I²: 66%).

CONCLUSIONS

In this study, a more intensive statin-based lipid-lowering treatment, compared with less intensive treatment or placebo, showed a similar incidence of worsening transaminases levels in patients with abnormal liver tests at baseline. Also, a reduction in cardiovascular events was observed when a more intensive lipid-lowering therapy was used.

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.

Nafcillin-Induced Hepatic Injury: A Case Report and Literature Review

Background: Drug-induced liver injury (DILI) is the most common cause of acute liver failure in the Western world. While it requires a diagnosis of exclusion, it is exceedingly prevalent in patients taking multiple hepatotoxic agents, the foremost of which are antibiotics, followed by herbal and dietary supplements. Below we will discuss a case of nafcillin-induced liver injury suggested by a thorough work-up and rule-out of other hepatic and biliary pathologies.

Case presentation: We report the case of a 66-year-old white male who presented with painless jaundice. Clinical, laboratory and radiographic features demonstrated a cholestatic pattern of liver injury without significant abnormalities in the biliary tract. All workup for viral hepatitis and autoimmune diseases with liver involvement was negative. Liver biopsy showed acute necro-inflammatory changes suggestive of drug-induced liver injury. The patient had received 18 days of IV nafcillin for blood culture positive methicillin-susceptible Staphylococcus aureus (MSSA) four weeks prior to his presentation. He showed clinical and laboratory improvement of his liver functions with supportive care only.

Conclusion: Nafcillin is a safe and effective antibiotic for the treatment of methicillin-susceptible Staphylococcal infections. However, physicians and prescribing healthcare professionals should be aware of the rare, but serious side effects, especially one of drug-induced liver injury with emphasis on the need for early cessation of nafcillin if liver function abnormalities develop.

Intestinal Dysbiosis Amplifies Acetaminophen-Induced Acute Liver Injury

BACKGROUND & AIMS

Acute liver failure (ALF) represents an unmet medical need in Western countries. Although the link between intestinal dysbiosis and chronic liver disease is well-established, there is little evidence for a functional role of gut-liver interaction during ALF. Here we hypothesized that intestinal dysbiosis may affect ALF.

METHODS

To test this hypothesis, we assessed the association of proton pump inhibitor (PPI) or long-term antibiotics (ABx) intake, which have both been linked to intestinal dysbiosis, and occurrence of ALF in the 500,000 participants of the UK BioBank population-based cohort. For functional studies, male Nlrp6-/- mice were used as a dysbiotic mouse model and injected with a sublethal dose of acetaminophen (APAP) or lipopolysaccharide (LPS) to induce ALF.

RESULTS

Multivariate Cox regression analyses revealed a significantly increased risk (odds ratio, 2.3-3) for developing ALF in UK BioBank participants with PPI or ABx. Similarly, dysbiotic Nlrp6-/- mice displayed exacerbated APAP- and LPS-induced liver injury, which was linked to significantly reduced gut and liver tissue microbiota diversity and correlated with increased intestinal permeability at baseline. Fecal microbiota transfer (FMT) from Nlrp6-/- mice into wild-type (WT) mice augmented liver injury on APAP treatment in recipient WT mice, resembling the inflammatory phenotype of Nlrp6-/- mice. Specifically, FMT skewed monocyte polarization in WT mice toward a Ly6Chi inflammatory phenotype, suggesting a critical function of these cells as sensors of gut-derived signals orchestrating the inflammatory response.

CONCLUSIONS

Our data show an important yet unknown function of intestinal microbiota during ALF. Intestinal dysbiosis was transferrable to healthy WT mice via FMT and aggravated liver injury. Our study highlights intestinal microbiota as a targetable risk factor for ALF.