Identification of Reduced ERAP2 Expression and a Novel HLA Allele as Components of a Risk Score for Susceptibility to Liver Injury Due to Amoxicillin-Clavulanate

Genetic variants associated with immune-mediated liver injury from checkpoint inhibitors

BACKGROUND

The clinical features, liver histology, and genetic variants in 57 patients with moderate to severe immune-mediated liver injury from checkpoint inhibitors (ILICI) are presented.

METHODS

Between 2010 and 2022, 57 high-causality ILICI cases were enrolled in the Drug-Induced Liver Injury Network. HLA and selected candidate gene variants were tested for association with ILICI risk compared to the general population and other DILI controls.

RESULTS

The 57 high-causality cases were attributed to pembrolizumab (16), ipilimumab (15), ipilimumab and nivolumab (13), and other immune checkpoint inhibitors (13) and occurred at a median of 72 days after the first infusion. Median age was 57.8 years, 66% male, and 89% were non-Hispanic Whites. At DILI onset, 53% had hepatocellular, 35% mixed, and 15% cholestatic, with younger patients more likely to have hepatocellular injury. The incidence of ANA, smooth muscle antibody, and elevated IgG levels was low (17%, 23%, and 0%), but corticosteroids were given to 86%. Microgranulomas and hepatic steatosis were seen in 54% and 46% of the 26 liver biopsies, respectively. The HLA alleles associated with autoimmune hepatitis were not over-represented, but 2 host immune response genes (EDIL3 and SAMA5A) and 3 other genes (GABRP, SMAD3, and SLCO1B1) were associated with ILICI (OR: 2.08-2.4, p<0.01).

CONCLUSIONS

ILICI typically arises within 12 weeks of initiating immunotherapy and is self-limited in most cases. Genetic variants involved in host T-cell regulation and drug disposition were identified, implicating these pathways in the pathogenesis of ILICI. If validated, these findings could lead to improved diagnostic instruments and possible treatments for ILICI.

Insights gained into the injury mechanism of drug and herb induced liver injury in the hepatic microenvironment

Drug-Induced Liver Injury (DILI) and herb Induced Liver Injury (HILI) continues to pose a substantial challenge in both clinical practice and drug development, representing a grave threat to patient well-being. This comprehensive review introduces a novel perspective on DILI and HILI by thoroughly exploring the intricate microenvironment of the liver. The dynamic interplay among hepatocytes, sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, cholangiocytes, and the intricate vascular network assumes a central role in drug metabolism and detoxification. Significantly, this microenvironment is emerging as a critical determinant of susceptibility to DILI and HILI. The review delves into the multifaceted interactions within the liver microenvironment, providing valuable insights into the complex mechanisms that underlie DILI and HILI. Furthermore, we discuss potential strategies for mitigating drug-induced liver injury by targeting these influential factors, emphasizing their clinical relevance. By highlighting recent advances and future prospects, our aim is to shed light on the promising avenue of leveraging the liver microenvironment for the prevention and mitigation of DILI and HILI. This deeper understanding is crucial for advancing clinical practices and ensuring patient safety in the realm of DILI and HILI.

Leveraging Random Effects in Cistrome-Wide Association Studies for Decoding the Genetic Determinants of Prostate Cancer

Cistrome-wide association studies (CWAS) are pivotal for identifying genetic determinants of diseases by correlating genetically regulated cistrome states with phenotypes. Traditional CWAS typically develops a model based on cistrome and genotype data to associate predicted cistrome states with phenotypes. The random effect cistrome-wide association study (RECWAS), reevaluates the necessity of cistrome state prediction in CWAS. RECWAS utilizes either a linear model or marginal effect for initial feature selection, followed by kernel-based feature aggregation for association testing is introduced. Through simulations and analysis of prostate cancer data, a thorough evaluation of CWAS and RECWAS is conducted. The results suggest that RECWAS offers improved power compared to traditional CWAS, identifying additional genomic regions associated with prostate cancer. CWAS identified 102 significant regions, while RECWAS found 50 additional significant regions compared to CWAS, many of which are validated. Validation encompassed a range of biological evidence, including risk signals from the GWAS catalog, susceptibility genes from the DisGeNET database, and enhancer-domain scores. RECWAS consistently demonstrated improved performance over traditional CWAS in identifying genomic regions associated with prostate cancer. These findings demonstrate the benefits of incorporating kernel methods into CWAS and provide new insights for genetic discovery in complex diseases.

ERAP-1 and ERAP-2 Variants in Liver Injury After COVID-19 mRNA Vaccination: A US Multicenter Study

INTRODUCTION

The aim of this study is to describe the presenting features, genetic factors, and outcomes of 23 adults who developed liver injury after coronavirus disease 2019 (COVID-19) mRNA vaccination.

METHODS

Patients with suspected COVID-19 vaccine hepatitis were enrolled into the Drug-Induced Liver Injury Network. Causality was assessed using the Drug-Induced Liver Injury Network expert opinion score. High-resolution HLA sequencing was undertaken using Illumina platform.

RESULTS

Amongst the 16 high causality cases, median time to onset was 16 days, median age was 63 years, and 75% were female. The injury was hepatocellular in 75% with a median alanine aminotransferase of 497 U/L, and 37% had jaundice. An antinuclear antibody and smooth muscle antibody were detectable in 27% and 36%, but only 12% had an elevated immunoglobulin G level. During follow-up, 37% received a short course of corticosteroids, and 88% fully recovered by 6 months with no deaths observed. HLA alleles associated with autoimmune hepatitis were not overrepresented compared with controls, but an ERAP-2 variant (rs1263907) and the ERAP-1 Hap6 haplotype were significantly overrepresented in the high causality cases vs controls ( P = 0.026 and 5 × 10 -5 , respectively).

DISCUSSION

Acute liver injury may arise within 8 weeks of COVID-19 mRNA vaccination that is generally mild and self-limited in most patients. The absence of an association with the AIH HLA alleles combined with the significant ERAP-2 and ERAP-1 Hap6 haplotype associations implicates a unique but very rare host immune response to vaccine-derived antigens in the pathogenesis of COVID-19 vaccine hepatotoxicity.

COVID-19 vaccine-induced liver injury

PURPOSE OF REVIEW

The rapid rollout and uptake of novel coronavirus disease 2019 (COVID-19) vaccines has been accompanied by a small yet noticeable accumulation of reports of liver injury occurring after vaccination. This review describes the present evidence surrounding COVID-19 vaccine-induced liver injury (VILI).

RECENT FINDINGS

Liver injury occurring after the COVID-19 vaccine often presents clinically similar to autoimmune hepatitis, with positive autoantibodies and a portal and lobular inflammatory infiltrate and varying degrees of necrosis on biopsy. The overwhelming majority of patients recover, often spontaneously or with a limited course of immunosuppression. The overall incidence of this phenomenon appears to be exceedingly low.

SUMMARY

Providers should remain vigilant for ongoing reports of VILI after COVID-19 and yet feel reassured by the low incidence and high likelihood of recovery. Ongoing genetic and histological study, as well as longer-term follow-up of presently identified cases, will shed further light on the clinical entity of VILI.

Hepatotoxicity of Antibiotics and Antifungals and Their Safe Use in Hepatic Impairment

Idiosyncratic drug-induced liver injury (DILI) is a rare and unpredictable form of hepatotoxicity. While its clinical course is usually benign, cases leading to liver transplantation or death can occur. Based on modern prospective registries, antimicrobials including antibiotics and antifungals are frequently implicated as common causes. Amoxicillin-clavulanate ranks as the most common cause for DILI in the Western World. Although the absolute risk of hepatotoxicity of these agents is low, as their usage is quite high, it is not uncommon for practitioners to encounter liver injury following the initiation of antibiotic or antifungal therapy. In this review article, mechanisms of hepatoxicity are presented. The adverse hepatic effects of well-established antibiotic and antifungal agents are described, including their frequency, severity, and pattern of injury and their HLA risks. We also review the drug labeling and prescription guidance from regulatory bodies, with a focus on individuals with hepatic impairment.

Incidence of amoxycillin-clavulanic acid associated hepatotoxicity in an Australian children's hospital

OBJECTIVES

Amoxycillin/clavulanic acid is the most common antimicrobial cause of drug-induced liver injury in adults. It is a less common cause of severe drug-related hepatotoxicity in children despite its frequent use. We studied the incidence, characteristics and predictive factors for amoxycillin/clavulanic acid hepatoxicity in children.

DESIGN

Retrospective cohort study of children who received oral or intravenous amoxycillin/clavulanic acid at a quaternary children's hospital over a 5-year period. Children were included if they had liver function tests (LFTs) determined at baseline, during and within 3 months after the treatment course. Causality was assessed using the Naranjo criteria for adverse drug reactions and Roussel Uclaf Causality Assessment Method.

RESULTS

Of 3271 children prescribed amoxycillin/clavulanic acid, 374 were included. Forty-nine (13%) had LFT abnormalities related to amoxycillin/clavulanic acid. Fourteen (3.6%) fulfilled Common Terminology Criteria for Adverse Events (CTCAE) grade 2 criteria with clinically significant hepatotoxicity. Age <2 years, sepsis, post-gastrointestinal surgical indications, prolonged treatment course of >7 days and higher cumulative amoxycillin (>10 g) and clavulanic acid dose (>1 g) were predictive of hepatotoxicity. The median time to resolution of LFT abnormalities was 4 weeks (range 3-7).

CONCLUSIONS

The incidence of amoxycillin/clavulanic acid related LFT abnormalities (CTCAE Grade 2 or above) in children was 3.6%. A prolonged treatment course >7 days, high cumulative amoxycillin (10 g) and clavulanic acid (>1 g) doses, those aged <2 years, and patients with sepsis or post-gastrointestinal surgery were predictive of a higher likelihood of abnormal LFTs. LFT monitoring should be considered in children receiving ≥7 days of treatment, particularly in those with other predisposing factors.

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

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

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Polygenic modelling and machine learning approaches in pharmacogenomics: Importance in downstream analysis of genome-wide association study data

Genome-wide association studies (GWAS) have identified genetic variations associated with adverse drug effects in pharmacogenomics (PGx) research. However, interpreting the biological implications of these associations remains a challenge. This review highlights 2 promising post-GWAS methods for PGx. First, we discuss the polygenic architecture of the PGx traits, especially for drug-induced liver injury. Experimental modelling using multiple donors' human primary hepatocytes and human liver organoids demonstrated the polygenic architecture of drug-induced liver injury susceptibility and found biological vulnerability in genetically high-risk tissue donors. Second, we discuss the challenges of interpreting the roles of variants in noncoding regions. Beyond methods involving expression quantitative trait locus analysis and massively parallel reporter assays, we suggest the use of in silico mutagenesis through machine learning methods to understand the roles of variants in transcriptional regulation. This review underscores the importance of these post-GWAS methods in providing critical insights into PGx, potentially facilitating drug development and personalized treatment.

Relevance of Pharmacogenomics to the Safe Use of Antimicrobials

There has been widespread implementation of pharmacogenomic testing to inform drug prescribing in medical specialties such as oncology and cardiology. Progress in using pharmacogenomic tests when prescribing antimicrobials has been more limited, though a relatively large number of pharmacogenomic studies on aspects such as idiosyncratic adverse drug reactions have now been performed for this drug class. Currently, there are recommendations in place from either National Regulatory Agencies and/or specialist Pharmacogenomics Advisory Groups concerning genotyping for specific variants in MT-RNR1 and CYP2C19 before prescribing aminoglycosides and voriconazole, respectively. Numerous additional pharmacogenomic associations have been reported concerning antimicrobial-related idiosyncratic adverse drug reactions, particularly involving specific HLA alleles, but, to date, the cost-effectiveness of genotyping prior to prescription has not been confirmed. Polygenic risk score determination has been investigated to a more limited extent but currently suffers from important limitations. Despite limited progress to date, the future widespread adoption of preemptive genotyping and genome sequencing may provide pharmacogenomic data to prescribers that can be used to inform prescribing and increase the safe use of antimicrobials.