Hepatic histological findings in suspected drug-induced liver injury: systematic evaluation and clinical associations

Mitophagy-mtROS axis contributes to anti-tuberculosis-induced liver injury through activation of the cGAS-STING pathway in rat hepatocytes

Tuberculosis (TB) remains a major worldwide healthcare issue, with anti-TB drugs playing a pivotal role in its treatment. However, the emergence of anti-TB drug-induced liver injury (ATB-DILI) poses a considerable challenge, undermining treatment efficacy and patient survival. This study investigates the underlying mechanisms of ATB-DILI, focusing on reactive oxygen species (ROS), mitophagy, lysosomal function, and the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling pathway. A rat hepatocyte model treated with standard anti-TB drugs was established to assess liver inflammation, oxidative stress biomarkers, mitochondrial function, and mitophagy processes. The results indicate that anti-TB drug administration induced significant inflammatory injury, characterized by elevated IL-6 and reduced IL-4 and IL-10 levels. ROS overproduction predominantly originates in the mitochondrial level, consequently resulting in oxidative stress and impaired mitochondrial function. A noticeable decline in both the oxygen consumption rate and ATP production is indicative of this phenomenon. Although mitophagy was activated, impaired lysosomal function hindered mitophagic flux, leading to the buildup of damaged mitochondria and ROS. Pharmacological intervention with mitoTEMPO alleviated mitochondrial dysfunction, while clioquinol restored lysosomal function and improved mitophagy. Additionally, the cGAS-STING signaling pathway was found to regulate inflammation in ATB-DILI, with both mitoTEMPO and clioquinol alleviating its effects. These findings elucidate the crucial impact of lysosome-mediated mitophagy dysfunction and mitochondrial ROS in ATB-DILI, highlighting potential therapeutic targets to enhance liver protection during anti-TB treatment.

Natural History of Idiosyncratic Drug-Induced Liver Injury and Prognostic Models

BACKGROUND AND AIMS

Drug-induced liver injury (DILI) remains a leading cause of acute liver failure worldwide. Drugs such as isoniazid, alone or in combination with other anti-tuberculosis drugs, as well as a growing number of herbal and complementary medicines, have been implicated in most cases of acute liver failure in registry studies.

METHODS

This review summarizes current knowdledge on the acute and chronic outcomes in patients with idiosyncratic DILI and discusses several of the existing prognostic models.

RESULTS AND CONCLUSIONS

The reasons why some individuals progress from DILI to end-stage liver disease are still largely unknown. However, collaborative efforts over the past few decades have provided figures on the relative incidence of drug-induced acute liver failure and allowed the development of prognostic models to predict this worse outcome at the onset of the event. The outcome of chronic DILI is less well characterised due to the lack of sufficient follow-up in cohort studies, but several phenotypes of DILI can progress to chronicity, and specific drugs such as nitrofurantoin or amiodarone are classic examples of agents leading to chronic forms of DILI. Therapy for drug-induced acute liver failure and chronic DILI is mainly supportive, although some randomised clinical trials have shown beneficial effects of N-acetylcysteine and corticosteroids.

Mechanisms of drug induced liver injury

Drug induced liver injury (DILI) is a serious and potentially life-threatening condition resulting from an adverse drug reaction. Both the clinical manifestations and pathological mechanisms of DILI vary depending on drug characteristics, dose, duration of exposure as well as host specific factors. Disease onset can occur within days or months after the introduction of a drug. This has challenged identification of disease specific biomarkers and resulted in delayed and even erroneous diagnosis of patients. Apart from discontinuation of current pharmacotherapy, options for DILI patients are scarce and the condition can sometimes continue or worsen after drugs are discontinued or result in irreversible liver damage such as cirrhosis. This illustrates the need to uncover relevant pathological pathways that will pave the road for targeted interventions. In an effort to accommodate these needs, novel insights from preclinical and cellular disease modeling have allowed coupling of specific drugs to potential mechanisms of toxicity. This review outlines three signaling pathways of DILI: organelle stress, cholestasis, and immune responses, discusses their interplay with oxidative stress, and provides examples of drugs specifically targeting one or more steps in these pathways. A systematic approach identifying specific mechanisms of DILI could allow for the assembly of large databases, in turn enabling advanced computational modelling to provide accurate predictions of the DILI potential of both known drugs and future drug candidates.

Two types of regenerative cell populations appear in acute liver injury

The liver has a robust regenerative capacity. However, the mechanisms underlying this process remain unclear. Numerous studies on liver regeneration have been previously conducted using partial hepatectomy models, which may not fully represent acute liver injury with inflammation and necrosis. This is commonly observed in the majority of clinical cases. In this study, we conducted a single-cell RNA sequencing (RNA-seq) analysis of liver regeneration in acetaminophen-treated mice using publicly available data. We found that two distinct populations of regenerative cells simultaneously appeared within the same regenerative process. The two populations significantly differed in terms of cell morphology, differentiation, localization, proliferation rate, and signal response. Moreover, one of the populations was induced by contact with necrotic tissue and demonstrated a higher proliferative capacity with a dedifferentiated feature. These findings provide new insights into liver regeneration and therapeutic strategies for liver failure.

Role of liver biopsy in the management of idiosyncratic DILI

Drug-induced liver injury (DILI) presents unique challenges in clinical practice. While some types of DILI are mild and resolve quickly after removing the drug, other situations are more complex, with competing aetiologies or underlying liver disease. Guidelines from professional societies agree that the liver biopsy retains a role in understanding and managing DILI in certain situations. Liver biopsy allows characterization of the histological pattern of injury as well as assessment of severity. Inflammatory infiltrates, bile duct injury or loss and vascular injury are all revealed by liver biopsy. Communication between the hepatopathologist and clinical team with clinicopathological correlation of the findings is necessary for the best determination of causality and differentiation from other diseases of exclusion, like autoimmune hepatitis and graft-versus-host disease. This review highlights important aspects of the role of liver biopsy in DILI evaluation.

Mitochondrial dysfunction in drug-induced hepatic steatosis: Recent findings and current concept

Mitochondrial activity is necessary for the maintenance of many liver functions. In particular, mitochondrial fatty acid oxidation (FAO) is required for energy production and lipid homeostasis. This key metabolic pathway is finely tuned by the mitochondrial respiratory chain (MRC) activity and different transcription factors such as peroxisome proliferator-activated receptor α (PPARα). Many drugs have been shown to cause mitochondrial dysfunction, which can lead to acute and chronic liver lesions. While severe inhibition of mitochondrial FAO would eventually cause microvesicular steatosis, hypoglycemia, and liver failure, moderate impairment of this metabolic pathway can induce macrovacuolar steatosis, which can progress in the long term to steatohepatitis and cirrhosis. Drugs can impair mitochondrial FAO through several mechanisms including direct inhibition of FAO enzymes, sequestration of coenzyme A and l-carnitine, impairment of the activity of one or several MRC complexes and reduced PPARα expression. In drug-induced macrovacuolar steatosis, non-mitochondrial mechanisms can also be involved in lipid accumulation including increased de novo lipogenesis and reduced very-low-density lipoprotein secretion. Nonetheless, mitochondrial dysfunction and subsequent oxidative stress appear to be key events in the progression of steatosis to steatohepatitis. Patients suffering from metabolic dysfunction-associated steatotic liver disease (MASLD) and treated with mitochondriotoxic drugs should be closely monitored to reduce the risk of acute liver injury or a faster transition of steatosis to steatohepatitis. Therapies based on the mitochondrial cofactor l-carnitine, the antioxidant N-acetylcysteine, or thyromimetics might be useful to prevent or treat drug-induced mitochondrial dysfunction, steatosis, and steatohepatitis.

The emerging role of alternatively activated macrophages to treat acute liver injury

Acute liver injury (ALI) has a clear requirement for novel therapies. One emerging option is the use of alternatively activated macrophages (AAMs); a distinct subtype of macrophage with a role in liver injury control and repair. In this comprehensive review, we provide an overview of the current limited options for ALI, and the potential advantages offered by AAMs. We describe the evidence supporting their use from in vitro studies, pre-clinical animal studies, and human clinical trials. We suggest why the first evidence for the clinical use of AAMs is likely to be found in acetaminophen toxicity, and discuss the specific evidence for AAM use in this population, as well as potential applications for AAMs in other patient populations. The key domains by which the performance of AAMs for the treatment of ALI will be assessed are identified, and remaining challenges to the successful delivery of AAMs to clinic are explored.

Drug-induced Liver Injury in Latin America: 10-year Experience of the Latin American DILI (LATINDILI) Network

BACKGROUND & AIMS

Latin America is a region of great interest for studying the clinical presentation of idiosyncratic drug-induced liver injury (DILI). A comprehensive analysis of patients enrolled into the LATINDILI Network over a decade is presented.

METHODS

Demographics, clinical presentation, histological findings and outcome of prospectively recruited DILI cases in the LATINDILI Network were analyzed. Suspected culprit drugs were classified according to the Anatomical Therapeutic Chemical classification. Causality was assessed using the Roussel Uclaf Causality Assessment Method (RUCAM) scale.

RESULTS

Overall, 468 idiosyncratic DILI cases were analyzed (62% women; mean age, 49 years). Hepatocellular injury predominated (62%); jaundice was present in 60% of patients, and 42% were hospitalized. Of the cases, 4.1% had a fatal outcome, and 24 patients (12%) developed chronic DILI. The most common drug classes were systemic anti-infectives (31%), musculoskeletal agents (12%), antineoplastic and immunomodulating agents (11%), and herbal and dietary supplements (9%). Notably, none of the patients with DILI due to antibacterials or immunosuppressants had a fatal outcome. In fact, Hy's law showed to have drug-specific predictive value, with anti-tuberculosis drugs, nimesulide, and herbal and dietary supplements associated with the worst outcome, whereas DILI caused by amoxicillin-clavulanate, nitrofurantoin, and diclofenac, which fulfilled Hy's law, did not have a fatal outcome.

CONCLUSION

Features of DILI in Latin America are comparable to other prospective registries. However, the pattern of drugs responsible for DILI differs. An increasing incidence of herbal and dietary supplements, with high mortality rate, and likewise, nimesulide and nitrofurantoin, was noted. Thus, public health policies should raise awareness of the potential adverse effects of these compounds.

Chinese Guideline for the Diagnosis and Management of Drug-Induced Liver Injury in Primary Care (2024)

Drug-induced liver injury (DILI) is a drug-induced disease that not only complicates the treatment of the primary disease but may also lead to acute liver failure or even death in severe cases. Drugs commonly used in primary care, such as anti-infective agents and nonsteroidal anti-inflammatory drugs, are major causes of DILI. In addition, a large elderly population, comorbidities, and combination therapy with multiple drugs increase the risk of DILI in primary care. Therefore, primary care providers should proactively screen and monitor high-risk patients to identify potential DILI timely. Currently, diagnosis of DILI relies on the exclusion of liver diseases of other etiologies. Collection of detailed medical history of the patients and careful exclusion of other potential liver injury of other etiologies are crucial for accurate diagnosis. This guideline, developed based on evidence-based medicine from the latest research, aimed to provide primary care providers with professional guidance on the timely identification of suspected DILI cases and standardized diagnosis and management in clinical practice.

A microRNA signature for valproate-induced steatosis in human hepatocytes and its application to predict fatty liver in paediatric epileptic patients on valproate therapy

Valproate (VPA) has been the first-line, most frequently prescribed antiepileptic drug in children over the past 50 years. VPA causes, idiosyncratic hepatotoxicity in some patients, who often presents with hepatic steatosis. Experimental studies also support that VPA has high potential to induce steatosis. However, there is an apparent lack of significant hepatic problems in neuropediatric units, likely because iatrogenic liver steatosis lacks specific biomarkers. Thus, it is possible that a relevant number of children under VPA have asymptomatic fatty liver. AIMS: 1) to demonstrate VPA-induced triglyceride (TG) accumulation in cultured human upcyte hepatocytes, 2) to identify miRNAs that are deregulated by VPA and associated with TG levels in these cells, and 3) to test these miRNAs, as potential non-invasive biomarkers, in plasma of paediatric epileptic patients on VPA, to identify those with a potential risk of liver steatosis. Human upcyte hepatocytes were exposed to subcytotoxic VPA concentrations. Hepatocytes increased intracellular TGs by 27 % and 45 % after 2 and 4 mM VPA for 24 h. The profiling of cellular miRNAs by microarray analysis after 4 mM VPA identified 43 deregulated human miRNAs (fold-change > 1.5 or < -1.5; FDR p<0.05). Some of them (n=11), which were validated by RTqPCR and showed correlation (Pearson r≥ 0.6) with intracellular TG levels, were selected as potential VPA-induced steatosis biomarkers. Next, we investigated the expression of these miRNAs in human plasma and found that 9 of them could be reliably quantified by RTqPCR: miR-485-3p, miR-127-3p, miR-30a-3p, miR-92b-3p, miR-212-3p, miR-182-5p, miR-183-5p, miR-500a-5p and miR-675-5p. Screening of this 9-miRNA signature in 80 paediatric epileptic patients on VPA identified 18 patients (23 %) that clustered separately because of important alterations in the selected plasma miRNAs. These patients were younger and had higher VPA blood concentrations and serum liver enzyme levels. In conclusion, VPA induced both TG accumulation and deregulation of a set of miRNAs in cultured human hepatocytes. Nine of these miRNAs have demonstrated potential as circulating biomarkers to identify VPA-induced steatosis in epileptic patients, which should require closer clinical follow-up.

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.

Advances in the study of the mechanism of action of miR‑22 in liver lesions (Review)

Globally, nearly 2 million deaths annually are attributed to the development of liver diseases, with liver cancer and cirrhosis being particularly prominent, which makes liver disease a significant global health concern. Cirrhosis is closely linked to the evolution of hepatitis, hepatic fibrosis and fatty liver. However, most liver diseases have an insidious onset, are challenging to treat and the prognosis and efficacy of current therapies are unsatisfactory, which can result in irreversible functional damage to the liver. Therefore, there is an urgent need to explore the molecular mechanisms underlying liver disease and identify new biomarkers and therapeutic targets. In previous years, microRNAs (miRs), a class of short non-coding RNAs comprising 17-25 nucleotides, have attracted attention for their roles in various types of liver diseases. Among them, miR-22 serves a unique role in mediating multiple pathway mechanisms and epigenetic modifications and can act both as an inhibitor of liver cancer and a metabolic blocker. Given its close association with the liver, several studies have reported that the differential expression of miR-22 regulates the metabolic process of liver cancer and is involved in the evolution of hepatic fibrosis and steatohepatitis, making it a potential target for early diagnosis and treatment. The present manuscript aimed to comprehensively review the key role of miR-22 in the evolution of liver diseases and offer valuable references and guidance for subsequent studies by identifying its specific mechanism of action and future development prospects.

Severe acute liver disease in adults: Contemporary role of histopathology

Liver biopsies have consistently contributed to our understanding of the pathogenesis and aetiologies of acute liver disease. As other diagnostic modalities have been developed and refined, the role of biopsy in the management of patients with acute liver failure (ALF), acute-on-chronic liver failure (ACLF) and acute hepatitis, including acute liver injury (ALI), has changed. Liver biopsy remains particularly valuable when first-line diagnostic algorithms fail to determine aetiology. Despite not being identified as a mandatory diagnostic tool in recent clinical guidelines for the management of ALF or ACLF, many centres continue to undertake biopsies given the relative safety of transjugular biopsy in this setting. Several studies have demonstrated that liver biopsy can provide prognostic information, particularly in the context of so-called indeterminate hepatitis, and is extremely useful in excluding conditions such as metastatic tumours that would preclude transplantation. In addition, its widespread use of percutaneous biopsies in cases of less severe acute liver injury, for example in the establishment of a diagnosis of acute presentation of autoimmune hepatitis or confirmation of a probable or definite drug-induced liver injury (DILI), has meant that many centres have seen a shift in the ratio of specimens they are receiving from patients with chronic to acute liver disease. Histopathologists therefore need to be equipped to deal with these challenging specimens. This overview provides an insight into the contemporary role of biopsies (as well as explant and autopsy material) in diagnosing acute liver disease. It outlines up-to-date clinical definitions of liver injury and considers recent recommendations for the diagnosis of AIH and drug-induced, autoimmune-like hepatitis (DI-AIH).

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.

Identification of microbial antigens in liver tissues involved in the pathogenesis of primary biliary cholangitis using 16S rRNA metagenome analysis

BACKGROUND

Multiple factors are involved in the pathogenesis of primary biliary cholangitis (PBC), a chronic cholestatic liver disease, characterized by intrahepatic cholangiopathy. In particular, studies have suggested that environmental factors such as the presence of granulomas in the portal vein region are important for the development of PBC. This study aimed to comprehensively analyze and identify foreign-derived antigens in PBC liver tissue to confirm their involvement in PBC pathogenesis.

METHODS

Portal areas and hepatocyte regions were selectively dissected from formalin-fixed paraffin-embedded PBC liver tissue samples using the microlaser method, followed by total DNA extraction. We then validated whether the bacterial strains identified through 16S rRNA metagenomic analysis were detected in PBC liver tissues.

RESULTS

The most frequently detected bacterial genera in the PBC liver tissue samples were Sphingomonas panacis, Providencia, and Cutibacterium. These bacterial genera were also detected in the other PBC samples. Validation for the detection of S. panacis, the most abundant genus, revealed polymerase chain reaction bands extracted from the portal areas of all samples. They were also more highly expressed than bands detected in the hepatocyte region.

CONCLUSION

S. panacis antigen was specifically detected in the portal areas of PBC liver tissues. The introduction of foreign-derived antigens into the liver as an environmental factor could be a possible mechanism for the development of PBC.

Clinical significance of transjugular liver biopsy in acute liver failure - a real-world analysis

BACKGROUND

Histopathological characterization obtained by transjugular liver biopsy (TJLB) may theoretically contribute to clarification of the exact aetiology of acute liver failure (ALF). It's unclear whether the histopathological information from TJLB, due to the small specimen size, significantly contributes to diagnosing ALF causes, guiding therapy decisions, or predicting overall prognosis. This retrospective study aimed to analyse safety and clinical significance of TJLB in patients with ALF.

METHODS

This retrospective, monocentric study investigated safety and efficacy of TJLB in patients with ALF over a ten-year period at a tertiary care transplant-center. The predictive value of various clinical and laboratory characteristics as well as histopathological findings obtained by TJLB on 28-day liver-transplant-free survival were evaluated by calculating uni- and multivariate Cox-proportional hazard regression models. Additional univariate logistic regression analyses were performed to explore the influence of degree of intrahepatic necrosis on the secondary endpoints intensive-care-unit (ICU) admission, need for endotracheal intubation, renal replacement therapy and high-urgency listing for LTX.

RESULTS

A total of 43 patients with ALF receiving TJLB were included into the study. In most cases (n = 39/43 cases) TJLB confirmed the initially already clinically presumed ALF aetiology and the therapeutic approach was unchanged by additional histological examination in the majority of patients (36/43 cases). However, in patients with a high suspicion for aetiologies potentially treatable by medical immunosuppression (e.g. AIH, GvHD), TJLB significantly influenced further treatment planning and/or adjustment. While the degree of intrahepatic necrosis showed significance in the univariate analysis (p = 0.04), it did not demonstrate a significant predictive effect on liver transplant-free survival in the multivariate analysis (p = 0.1). Only consecutive ICU admission was more likely with higher extent of intrahepatic necrosis (Odds ratio (OR) 1.04 (95% CI 1-1.08), p = 0.046).

CONCLUSIONS

Performance of TJLB in ALF led to a change in suspected diagnosis and to a significant change in therapeutic measures only in those patients with a presumed high risk for aetiologies potentially responsive to immunosuppressive therapy. Clinical assessment alone was accurate enough, with additional histopathological examination adding no significant value, to predict overall prognosis of patients with ALF.

Drug-induced impairment of mitochondrial fatty acid oxidation and steatosis: assessment of causal relationship with 45 pharmaceuticals

Drug-induced liver injury (DILI) represents a major issue for pharmaceutical companies, being a potential cause of black-box warnings on marketed pharmaceuticals, or drug withdrawal from the market. Lipid accumulation in the liver also referred to as steatosis, may be secondary to impaired mitochondrial fatty acid oxidation (mtFAO). However, an overall causal relationship between drug-induced mtFAO inhibition and the occurrence of steatosis in patients has not yet been established with a high number of pharmaceuticals. Hence, 32 steatogenic and 13 nonsteatogenic drugs were tested for their ability to inhibit mtFAO in isolated mouse liver mitochondria. To this end, mitochondrial respiration was measured with palmitoyl-l-carnitine, palmitoyl-CoA + l-carnitine, or octanoyl- l-carnitine. This mtFAO tri-parametric assay was able to predict the occurrence of steatosis in patients with a sensitivity and positive predictive value above 88%. To get further information regarding the mechanism of drug-induced mtFAO impairment, mitochondrial respiration was also measured with malate/glutamate or succinate. Drugs such as diclofenac, methotrexate, and troglitazone could inhibit mtFAO secondary to an impairment of the mitochondrial respiratory chain, whereas dexamethasone, olanzapine, and zidovudine appeared to impair mtFAO directly. Mitochondrial swelling, transmembrane potential, and production of reactive oxygen species were also assessed for all compounds. Only the steatogenic drugs amiodarone, ketoconazole, lovastatin, and toremifene altered all these 3 mitochondrial parameters. In conclusion, our tri-parametric mtFAO assay could be useful in predicting the occurrence of steatosis in patients. The combination of this assay with other mitochondrial parameters could also help to better understand the mechanism of drug-induced mtFAO inhibition.

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.

Comparison of the recommendation of international autoimmune hepatitis pathology group 2022 and the simplified criteria for autoimmune hepatitis 2008: A preliminary study

Background and Aim

The histological diagnosis of autoimmune hepatitis (AIH) is challenging. A new consensus recommendation was provided by the International AIH Pathology Group to address the problems in the histological diagnosis. The purpose of this study is to compare the 2008 'simplified' criteria for AIH with the 'consensus recommendation' of 2022 in terms of diagnostic sensitivity.

Materials and Methods

A retrospective analysis was conducted on pathological specimens of patients diagnosed with Autoimmune Hepatitis (AIH) between 2010 and 2022. Out of 188 patients enlisted, 88 were selected based on exclusion criteria. The specimens were examined by two experienced hepatopathologists and a resident pathologist. All specimens were analyzed using both the "simplified" criteria and the new consensus recommendations.

Results

Out of a total of 78 patients, the 2022 consensus recommendations raised the diagnostic category of 16 patients (20.5%) to a higher level. Six patients who were previously diagnosed as "atypical" were now considered "possible AIH", while 10 patients with a "compatible" diagnosis were elevated to "likely AIH" category. No patients were found to fall into a lower diagnostic category according to the new recommendations. A significant difference in diagnostic sensitivity was observed between the 2008 criteria and the 2022 consensus report (p<0.001).

Conclusion

The 2022 consensus recommendation may be more sensitive in the diagnosis of AIH in comparison to the 2008 'simplified' histological criteria. More studies are needed both for the validation of the sensitivity of the new consensus recommendation and for the determination of the specificity.

Drug-induced Liver Injury from Intravenous Immunoglobulin for Prevention of Recurrent Gestational Alloimmune Liver Disease: A Clinical Catch-22

Gestational alloimmune liver disease (GALD) is a rare autoimmune syndrome in which maternal antibodies lead to in utero fetal hepatocyte destruction, often presenting as neonatal liver failure and hemochromatosis. Antenatal intravenous immunoglobulin (IVIG) is generally accepted to be safe in pregnancy with demonstrable benefits for reducing GALD recurrence risk in subsequent pregnancies. Here we present a case of a 33-year-old woman with a prior neonatal demise due to GALD who received multiple prophylactic IVIG infusions in a subsequent twin pregnancy complicated by maternal jaundice and acute hepatitis. A liver biopsy demonstrated hepatocellular injury with bridging necrosis and cholestatic features consistent with drug-induced liver injury. This case demonstrates the importance of close clinical monitoring during IVIG therapy and the need for further research into alternative prophylaxis options for GALD. Key Points GALD is a rare antibody-mediated autoimmune syndrome with high recurrence risk.IVIG can be effective in reducing risk of GALD recurrence and fetal loss.Patient's receiving ongoing IVIG therapy should be closely monitored for developing adverse effects, including DILI.

Does drug-induced liver injury still occur after sevoflurane anesthesia? -A case report

BACKGROUND

Several factors contribute to post-anesthetic hepatic dysfunction, including a decrease in oxygen supply to the liver, direct physical compression of the liver, viral hepatitis, blood transfusions, preexisting hepatic dysfunction, and the use of hepatotoxic drugs. Diagnosing volatile anesthetic drug-induced liver injury (VA-DILI) involves excluding these causes.

CASE

The patient underwent total mastectomy under anesthesia using sevoflurane. He had diabetes, and no abnormal results were found on preoperative laboratory examinations, and surgery was uneventful. Abnormal laboratory findings were observed after surgery, including an aspartate aminotransferase level of 1,417 IU/L, an alanine aminotransferase level of 2,176 IU/L, and a total bilirubin level of 3.8 mg/dl. He presented with symptoms of mild icteric sclera, fatigue, and pruritus. After ruling out other causes of liver injury, we concluded that these results indicated VA-DILI.

CONCLUSIONS

VA-DILI, though rare, we should be aware of the association between the disease and the use of halogenated anesthetics.

Inflammatory Bowel Disease Therapies and Acute Liver Injury

Drug-induced liver disease (DILI) represents one of the main problems in the therapeutic field. There are several non-modifiable risk factors, such as age and sex, and all drugs can cause hepatotoxicity of varying degrees, including those for the treatment of inflammatory bowel diseases (IBD). The aim of this review is to illustrate the adverse effects on the liver of the various drugs used in the treatment of IBD, highlighting which drugs are safest to use based on current knowledge. The mechanism by which drugs cause hepatotoxicity is not fully understood. A possible cause is represented by the formation of toxic metabolites, which in some patients may be increased due to alterations in the enzymatic apparatus involved in drug metabolism. Various studies have shown that the drugs that can most frequently cause hepatotoxicity are immunosuppressants, while mesalazine and biological drugs are, for the most part, less associated with such complications. Therefore, it is possible to assume that in the future, biological therapies could become the first line for the treatment of IBD.

Drug-induced liver injury (DILI) ascribed to non-steroidal anti-inflammatory drugs (NSAIDs) in the USA-Update with genetic correlations

OBJECTIVE

To describe patients with NSAID-DILI, including genetic factors associated with idiosyncratic DILI.

METHODS

In DILIN, subjects with presumed DILI are enrolled and followed for at least 6 months. Causality is adjudicated by a Delphic approach. HLA sequencing of multiethnic NSAID-DILI patients and HLA allele imputation of matching population controls were performed following overall, class and drug-based association analysis. Significant results were tested in a non-Hispanic White (NHW) case-control replication cohort.

RESULTS

Between September 2004 and March 2022, causality was adjudicated in 2498, and 55 (41 [75%] women) were assessed as likely due to NSAIDs. Median age at onset was 55 y (range 22-83 y). Diclofenac was the causative drug in 29, celecoxib in 7, ibuprofen in 5, etodolac and meloxicam each in 4. Except for meloxicam and oxaprozin (n = 2), the liver injury was hepatocellular with median R 15-25. HLA-DRB1*04:03 and HLA-B*35:03 were significantly more frequent in NSAID-DILI patients than in non-NSAID DILI controls. Interestingly, 85% of the HLA-DRB1*04:03 carriers developed DILI due to the use of acetic acid derivative NSAIDs, supporting the hypothesis that HLA-DRB1*04:03 could be a drug and/or class risk factor. HLA-B*35:03 but not HLA-DRB1*04:03 association was confirmed in the independent NHW replication cohort, which was largely driven by diclofenac.

CONCLUSIONS

Despite prevalent use, NSAID-DILI is infrequent in the United States. Diclofenac is the most commonly implicated, and adherence to warnings of risk and close observation are recommended. The increased frequency of HLA-B*35:03 and DRB1*04:03, driven by diclofenac, suggests the importance of immune-mediated responses.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Granulomas in Pediatric Liver Biopsies: Single Center Experience

BACKGROUND

Granulomas in pediatric liver biopsies (GPLB) are rare with the largest pediatric cohort reported over 25 years ago.

METHODS

Single-center retrospective study of GPLB.

RESULTS

Seventeen liver biopsies from 16 patients with granulomas were identified (9 boys, 56%) with a median age of 13 years (range: 1-18) for which the most common indication was the presence of a nodule/mass (47%). Significant comorbidities were seen in 13 patients (81%) and included: liver transplant (25%), history of a neoplasm (25%), autoimmune hepatitis (6%), Crohn disease (6%), bipolar disorder (6%), severe combined immunodeficiency (6%), and sickle cell disease (6%). Eleven patients were taking multiple medications at the time of biopsy. Granulomas were more commonly pan-acinar (11 cases) followed by subcapsular (4 cases), portal (1 case), and periportal (1 case). Necrosis was seen in 10 cases (59%). GMS stain was positive in 2 cases for Histoplasma-like yeast; microbiological cultures were negative in all cases (no: 4). A 18S and 16S rRNA gene sequencing performed in 15 cases revealed only 1 with a pathogenic microorganism, Mycobacterium angelicum.

CONCLUSION

In our experience, GPLB are heterogenous with only 3 cases having an identifiable infectious etiology and many of the remaining cases being associated to multiple medications, suggesting drug-induced liver injury as possible etiology.

Validation of the revised electronic version of RUCAM for diagnosis of DILI in Chinese patients

BACKGROUND AIMS

The Revised Electronic Causality Assessment Method (RECAM), a computerized update of the Roussel Uclaf Causality Assessment Methodology (RUCAM), was recently proposed. In this study, we validated and compared the utility of the RECAM and RUCAM in Chinese patients with a single conventional or herbal agent-induced liver injury.

METHODS

In this retrospective multicenter cohort of well-established DILI and non-DILI patients from 5 centers in China, the diagnostic performance of the RUCAM and RECAM was compared by AUC analysis. The consistency was evaluated by weighted kappa. The major causes of discrepancy were explored.

RESULTS

A total of 481 DILI and 100 non-DILI patients were included. In total, 62.6% of the DILI cases were induced by conventional agents, and 37.4% were induced by herbs. The RECAM had relatively higher AUC than RUCAM for overall [0.947 (0.926-0.964) vs. 0.867 (0.836-0.893), p=0.0016], conventional agents [0.923 (0.890-0.949) vs. 0.819 (0.775-0.858), p=0.0185], and herbs [0.972 (0.941-0.989) vs.0.911 (0.866-0.944), p=0.0199]. Latency, scores associated with hepatitis B, and hepatotoxicity information of the insulting drugs were the 3 main causes for the inconsistency between RECAM and RUCAM scores.

CONCLUSIONS

The RECAM had relatively better diagnostic performance than RUCAM, with a higher AUC for Chinese DILI patients. Timely updates of the LiverTox category and refinement of serum markers to exclude hepatitis B activity would further improve the applicability of RECAM in areas where the use of herbs and resolution of past HBV infections are common.

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

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

Granulomatous liver diseases

A granuloma is a discrete collection of activated macrophages and other inflammatory cells. Hepatic granulomas can be a manifestation of localized liver disease or be a part of a systemic process, usually infectious or autoimmune. A liver biopsy is required for the detection and evaluation of granulomatous liver diseases. The prevalence of granulomas on liver biopsy varies from 1% to 15%. They may be an incidental finding in an asymptomatic individual, or they may represent granulomatous hepatitis with potential to progress to liver failure, or in chronic disease, to cirrhosis. This review focuses on pathogenesis, histological features of granulomatous liver diseases, and most common etiologies, knowledge that is essential for timely diagnosis and intervention.

Comparative histologic features among liver biopsies with biliary-pattern injury and confirmed clinical diagnoses

Biliary-pattern injury in the liver (eg, duct injury, ductular reaction, cholestasis) can occur in several conditions, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), large duct obstruction (LDO), and drug-induced liver injury (DILI). While the histologic changes in these conditions have been individually well described, distinguishing among them remains often challenging, particularly when biopsy samples are limited in size, robust clinical information is unavailable, and/or the pathologist does not feel confident in evaluating liver disease. This study evaluated histologic features that could aid the diagnosis of biliary-pattern injury on biopsy. We reviewed 121 liver biopsies from clinically confirmed cases of PBC, PSC, chronic LDO, or DILI for multiple clinical and histologic parameters. The rates of these histologic findings were then compared among different entities. Onion-skin fibrosis was seen in 14% of PSC in comparison to 0%, 5%, and 0% of PBC, DILI, and chronic LDO (P = 0.031). Florid duct lesions were identified in 21% of PBC compared to 2% of PSC and 0% of DILI and LDO (P = 0.0065). Similarly, 42% of PBC showed lobular granulomas, compared to 7% of PSC, 11% of DILI, and 33% of chronic LDO (P = 0.0001). Cholestasis was more commonly seen in DILI (42%) and chronic LDO (83%) than in PBC (4%) and PSC (16%) (P < 0.0001). Lobular chronic inflammation was found in a significantly higher percentage of PBC and LDO than of PSC and DILI (P = 0.0009). There were significantly fewer cases of PBC showing neutrophils in ductular reaction than PSC, DILI, and LDO (P = 0.0063). Histologic findings that can help suggest a diagnosis in liver biopsies with biliary-pattern injury include florid duct lesions, lobular granulomas, lack of neutrophils in ductular reaction, and lobular chronic inflammation in PBC; onion-skin fibrosis in PSC; cholestasis and feathery degeneration in DILI; and lobular granulomas, lobular chronic inflammation, cholestasis, and feathery degeneration in chronic LDO. These findings are likely most helpful when complicating factors interfere with biopsy interpretation.

CONCURRENT IRON OVERLOAD AND NEOPLASIA IN LESCHENAULT'S ROUSETTES (ROUSETTUS LESCHENAULTII): A CASE SERIES

This case series investigates a cluster of deaths in a captive colony of Leschenault's rousettes (Rousettus leschenaultii). Six of seven bats that died between March and September 2021 were diagnosed postmortem with both iron overload (IO) and neoplasia, neither of which have previously been reported in this species. Iron status was assessed via hepatic histopathological grading, hepatic iron concentration, and, in two cases, serum iron concentration. On histopathological grading, all cases had hemochromatosis except one, which had hemosiderosis. Hepatic iron concentrations did not correlate with histopathological grading. Neoplasms in these six bats included hepatocellular carcinoma (HCC; 4), bronchioloalveolar adenocarcinoma (1), pancreatic adenocarcinoma (1), and sarcoma of the spleen and stomach (1). One bat had two neoplasms (HCC and sarcoma of the spleen and stomach). One additional case of HCC in 2018 was identified on retrospective case review. Etiology was investigated to the extent possible in a clinical setting. Nutritional analysis and drinking water testing found oral iron intake within acceptable bounds; however, dietary vitamin C was potentially excessive and may have contributed to IO. Panhepadnavirus PCR testing of liver tissue was negative for all bats. A species-associated susceptibility to IO, as seen in Egyptian fruit bats (Rousettus aegyptiacus), is possible. The high incidence of HCC is suspected to be related to IO; other differentials include viral infection. Causes or contributing factors were not definitively identified for the other neoplasms seen but could include age, inherited risk (given a high level of inbreeding), or an oncogenic virus. Pending further research in this species, it is recommended that keepers of Leschenault's rousettes offer conservative amounts of vitamin C and iron (as for Egyptian fruit bats), submit for postmortem examination any euthanized or found dead, and share records of similar cases.

Recent advances in the diagnosis of drug-induced liver injury

Drug-induced liver injury (DILI) is a major problem in the United States, commonly leading to hospital admission. Diagnosing DILI is difficult as it is a diagnosis of exclusion requiring a temporal relationship between drug exposure and liver injury and a thorough work up for other causes. In addition, DILI has a very variable clinical and histologic presentation that can mimic many different etiologies of liver disease. Objective scoring systems can assess the probability that a drug caused the liver injury but liver biopsy findings are not part of the criteria used in these systems. This review will address some of the recent updates to the scoring systems and the role of liver biopsy in the diagnosis of DILI.

UDCA for Drug-Induced Liver Disease: Clinical and Pathophysiological Basis

Drug-induced liver injury (DILI) is an adverse reaction to medications and other xenobiotics that leads to liver dysfunction. Based on differential clinical patterns of injury, DILI is classified into hepatocellular, cholestatic, and mixed types; although hepatocellular DILI is associated with inflammation, necrosis, and apoptosis, cholestatic DILI is associated with bile plugs and bile duct paucity. Ursodeoxycholic acid (UDCA) has been empirically used as a supportive drug mainly in cholestatic DILI, but both curative and prophylactic beneficial effects have been observed for hepatocellular DILI as well, according to preliminary clinical studies. This could reflect the fact that UDCA has a plethora of beneficial effects potentially useful to treat the wide range of injuries with different etiologies and pathomechanisms occurring in both types of DILI, including anticholestatic, antioxidant, anti-inflammatory, antiapoptotic, antinecrotic, mitoprotective, endoplasmic reticulum stress alleviating, and immunomodulatory properties. In this review, a revision of the literature has been performed to evaluate the efficacy of UDCA across the whole DILI spectrum, and these findings were associated with the multiple mechanisms of UDCA hepatoprotection. This should help better rationalize and systematize the use of this versatile and safe hepatoprotector in each type of DILI scenarios.

Chronic Drug-Induced Liver Injury from Labetalol during the Postpartum Period: A Case Report

Drug-induced liver injury (DILI) is a common cause of transaminitis in pregnancy. A 34-year-old G3P2012 presented 3 weeks postpartum for preeclampsia with severe features. After receiving acute antihypertensive medications, she was discharged home with labetalol. She presented 5 months later with general malaise, scleral icterus, nausea, and mild right upper quadrant pain and found to have significantly elevated transaminitis. She had a negative infectious, autoimmune, biliary, and steatohepatitis workup. A liver biopsy was performed supporting the diagnosis of DILI. After patient self-discontinued labetalol, her hepatitis significantly improved. However, she developed chronic DILI and liver enzymes normalized during her subsequent pregnancy at 34 weeks. Patient's written consent was obtained for this case report. Chronic DILI secondary to labetalol use is a rare and potentially fatal condition that should be considered on the differential for transaminitis during pregnancy and postpartum period.

Liver biopsy for assessment of suspected drug-induced liver injury in metabolic dysfunction-associated steatohepatitis clinical trials: Expert consensus from the Liver Forum

BACKGROUND

Causality assessment of suspected drug-induced liver injury (DILI) during metabolic dysfunction-associated steatohepatitis (MASH) clinical trials can be challenging, and liver biopsies are not routinely performed as part of this evaluation. While the field is moving away from liver biopsy as a diagnostic and prognostic tool, information not identified by non-invasive testing may be provided on histology.

AIM

To address the appropriate utilisation of liver biopsy as part of DILI causality assessment in this setting.

METHODS

From 2020 to 2022, the Liver Forum convened a series of webinars on issues pertaining to liver biopsy during MASH trials. The Histology Working Group was formed to generate a series of consensus documents addressing these challenges. This manuscript focuses on liver biopsy as part of DILI causality assessment.

RESULTS

Expert opinion, guidance and recommendations on the role of liver biopsy as part of causality assessment of suspected DILI occurring during clinical trials for a drug(s) being developed for MASH are provided. Lessons learned from prior MASH programs are reviewed and gaps identified.

CONCLUSIONS

Although there are no pathognomonic features, histologic evaluation of suspected DILI during MASH clinical trials may alter patient management, define the pattern and severity of injury, detect findings that favour a diagnosis of DILI versus MASH progression, identify prognostic features, characterise the clinicopathological phenotype of DILI, and/or define lesions that influence decisions about trial discontinuation and further development of the drug.

Histopathological characteristics of liver biopsy performed at different time points in drug-induced liver injury

BACKGROUND AND AIMS

Liver biopsy can provide critical information in patients with drug-induced liver injury (DILI). Our study aimed to compare the histopathological features of DILI at different time points from the onset to liver biopsy.

METHODS

We conducted a single-centre retrospective observational study. The clinical and follow-up data were extracted, and the pathological slides were reviewed.

RESULTS

129 patients were included. The median age was 52 and 75% were women. They were divided into <1 month, 1-3 months, and >3 months groups according to the durations from onset of the disorder to liver biopsy. The aminotransferase, alkaline phosphatase, and bilirubin levels showed no significant differences at onset but significantly decreased with time among the three groups (all p<0.05) at the time of liver biopsy. Histological injury patterns were significantly different among the three groups (p<0.01). Hepatocellular, canalicular, and cholestasis of Kupffer cells were significantly less frequent in the >3 months group (p<0.01). For patients taking herbs, bridging necrosis and cholestatic injury were significantly more frequent in the <1 month group (p<0.01). Furthermore, ductopenia, cholate stasis, and foam-like cells were equally distributed in the three groups but were significantly associated with poor prognosis.

CONCLUSIONS

Biopsy time significantly affects liver pathology: the earlier, the more acute cholestatic-hepatitic pattern, the later, the more chronic injury patterns. The prognostic features (ductopenia, cholate stasis, and foam-like cells) occurred equally in all three groups. Our study provides valuable information for liver pathologists aiding in their better interpretation of the liver biopsy from patients with DILI.

Fatty liver disease that is neither metabolic nor alcoholic

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. This article aims to summary less common etiologies of fatty liver and their key clinicopathological features.

Histopathological Features Predicting Long-term Clinical Outcomes in Patients with Vanishing Bile Duct Syndrome

Background and Aims

The clinicopathological features and long-term outcomes of patients with vanishing bile duct syndrome (VBDS) have yet to be elucidated. The study aims to investigate these features and identify factors associated with poor prognosis.

Methods

This multicenter retrospective study recruited patients with liver biopsy-proven VBDS who were followed up at five hospitals in northern China from January 2003 to April 2022. Clinical and pathological data at time of biopsy were reviewed. Clinical outcomes including cirrhosis, decompensation events, liver transplantation (LT), and liver-related death were recorded. Cox regression analysis was used to identify the risk factors associated with poor outcomes.

Results

A total of 183 patients were included. The median age was 47 years, with 77.6% being women. During a median follow-up of 4.8 years, 88 patients developed compensated or decompensated cirrhosis, 27 died, and 15 received LT. Multivariate Cox regression analysis showed that hepatocellular cholestasis (HR 2.953, 95% CI: 1.437-6.069), foam cells (HR 2.349, 95% CI: 1.092-5.053), and advanced fibrosis (HR 2.524, 95% CI: 1.313-4.851) were independent predictors of LT or liver-related deaths. A nomogram formulated with the above factors showed good consistency with a concordance index of 0.746 (95% CI: 0.706-0.785).

Conclusions

Nearly half of VBDS patients studied progressed to end-stage liver disease and 23% of them had LT or liver-related death within two years of diagnosis. Hepatocellular cholestasis, foam cells and advanced fibrosis rather than the degree of bile duct loss or underlying etiologies were independently associated with poor prognosis in VBDS patients.

Application of multiple-finding segmentation utilizing Mask R-CNN-based deep learning in a rat model of drug-induced liver injury

Drug-induced liver injury (DILI) presents significant diagnostic challenges, and recently artificial intelligence-based deep learning technology has been used to predict various hepatic findings. In this study, we trained a set of Mask R-CNN-based deep algorithms to learn and quantify typical toxicant induced-histopathological lesions, portal area, and connective tissue in Sprague Dawley rats. We compared a set of single-finding models (SFMs) and a combined multiple-finding model (MFM) for their ability to simultaneously detect, classify, and quantify multiple hepatic findings on rat liver slide images. All of the SFMs yielded mean average precision (mAP) values above 85%, suggesting that the models had been successfully established. The MFM showed better performance than the SFMs, with a total mAP value of 92.46%. We compared the model predictions for slide images with ground-truth annotations generated by an accredited pathologist. For the MFM, the overall and individual finding predictions were highly correlated with the annotated areas, with R-squared values of 0.852, 0.952, 0.999, 0.990, and 0.958 being obtained for portal area, infiltration, necrosis, vacuolation, and connective tissue (including fibrosis), respectively. Our results indicate that the proposed MFM could be a useful tool for detecting and predicting multiple hepatic findings in basic non-clinical study settings.

A gene expression profile-based approach to screen the occurrence and predisposed host characteristics of drug-induced liver injury: a case study of Psoralea corylifolia Linn

Drug-induced liver injury (DILI) is one of the most common causes of a drug being withdrawn, and identifying the culprit drugs and the host factors at risk of causing DILI has become a current challenge. Recent studies have found that immune status plays a considerable role in the development of DILI. In this study, DILI-related differentially expressed genes mediated by immunoinflammatory cytokines were obtained from the Gene Expression Omnibus (GEO) database to predict the occurrence of DILI (named the DILI predictive gene set, DILI_PGS), and the predictability of the DILI_PGS was verified using the Connectivity Map (CMap) and LiverTox platforms. The results obtained DILI_PGS from the GEO database could predict 81.25% of liver injury drugs. In addition, the Coexpedia platform was used to predict the DILI_PGS-related characteristics of common host diseases and found that the DILI_PGS mainly involved immune-related diseases and tumor-related diseases. Then, animal models of immune stress (IS) and immunosuppressive (IP) were selected to simulate the immune status of the above diseases. Meanwhile, psoralen, a main component derived from Psoralea corylifolia Linn. with definite hepatotoxicity, was selected as an experimental drug with highly similar molecular fingerprints to three idiosyncratic hepatotoxic drugs (nefazodone, trovafloxacin, and nimesulide) from the same DILI_PGS dataset. The animal experiment results found a single administration of psoralen could significantly induce liver injury in IS mice, while there was no obvious liver function change in IP mice by repeatedly administering the same dose of psoralen, and the potential mechanism of psoralen-induced liver injury in IS mice may be related to regulating the expression of the TNF-related pathway. In conclusion, this study constructed the DILI_PGS with high accuracy to predict the occurrence of DILI and preliminarily identified the characteristics of host factors inducing DILI.

Toxicity of targeted anticancer treatments on the liver in myeloproliferative neoplasms

The liver has a central role in metabolism, therefore, it is susceptible to harmful effects of ingested medications (drugs, herbs, and nutritional supplements). Drug-induced liver injury (DILI) comprises a range of unexpected reactions that occur after exposure to various classes of medication. Even though most cases consist of mild, temporary elevations in liver enzyme markers, DILI can also manifest as acute liver failure in some patients and can be associated with mortality. Herein, we briefly review available data on DILI induced by targeted anticancer agents in managing classical myeloproliferative neoplasms: Chronic myeloid leukemia, polycythemia vera, essential thrombocythemia, and myelofibrosis.

Liver Pathology After Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation is used to treat a variety of hematologic malignancies and autoimmune conditions. The immunosuppressive medications as well as other therapies used both before and after transplantation leave patients susceptible to a wide spectrum of complications, including liver injury. Causes for liver damage associated with stem cell transplantation include sinusoidal obstruction syndrome, graft-versus-host disease, iron overload, and opportunistic infection. Here, the authors review the clinical and pathological findings of these etiologies of liver injury and provide a framework for diagnosis.

Biomarkers of liver diseases

The liver is one of the pivotal organs in the human body and is fundamentally responsible for detoxification and metabolism. Various disorders such as non-alcoholic fatty liver disease, fibrosis, cirrhosis, hepatocellular carcinoma, and hepatitis are associated with improper functions of the liver. Hence, biomarkers are needed to determine the severity. Further, many liver enzymes, including the cascade of aspartate aminotransferase (AST)/serum glutamic oxaloacetic transaminase (SGOT), alanine aminotransferase (ALT)/serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), and total bilirubin (TBIL), are conventional liver biomarkers. They are not, however, unique to the liver; hence, efforts are being made to identify the precise biomarkers for liver illness that can target liver diseases. HMGB1, cytokeratin 18 (K18), glutathione-S-transferase-α (GST-α), glutamate dehydrogenase (GLDH), malate dehydrogenase (MDH), and microRNAs (miRNA) are a few examples of developing biomarkers used to detect many liver diseases. Hence, the review has highlighted various novel biomarkers of the liver so that various pathophysiological pathways and treatments can be made easier.

The Impact of Patient Age and Corticosteroids in Patients With Sulfonamide Hepatotoxicity

INTRODUCTION

Sulfonamides are widely used to treat and prevent various bacterial and opportunistic infections. The aim of this study was to describe the clinical presentation and outcomes of a large cohort of patients with sulfonamide hepatotoxicity.

METHODS

Between 2004 and 2020, 105 patients with hepatotoxicity attributed to trimethoprim/sulfamethoxazole (TMP-SMZ) (n = 93) or other sulfonamides (n = 12) were enrolled. Available liver biopsies were reviewed by a single hepatopathologist.

RESULTS

Among the 93 TMP-SMZ cases, 52% were female, 7.5% younger than 20 years, and the median time to drug-induced liver injury (DILI) onset was 22 days (range: 3-157). Younger patients were significantly more likely to have rash, fever, eosinophilia, and a hepatocellular injury pattern at onset that persisted at the peak of liver injury compared with older patients ( P < 0.05). The 18 (19%) TMP-SMZ patients treated with corticosteroids had more severe liver injury and a higher mortality but a trend toward more rapid normalization of their laboratory abnormalities compared with untreated patients. During follow-up, 6.2% of the TMP-SMZ patients died or underwent liver transplantation. Chronic DILI developed in 20% and was associated with cholestatic injury at onset and higher peak total bilirubin levels.

DISCUSSION

Sulfonamide hepatotoxicity is characterized by a short drug latency with frequent hypersensitivity features at onset. Subject age is an important determinant of the laboratory profile at presentation, and patients with cholestasis and higher total bilirubin levels were at increased risk of developing chronic DILI. Corticosteroids may benefit a subgroup of patients with severe injury, but further studies are needed.

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.

Pathology of Acute and Acute-on-Chronic Liver Failure

Liver failure can develop as either acute liver failure in the absence of preexisting liver disease, or as acute-on-chronic liver failure in a patient with underlying chronic liver disease or cirrhosis. A timely liver biopsy is helpful to distinguish acute and chronic liver disease, identify precipitating factors, provide prognostic information based on pathologic changes, and aid in making appropriate decisions for patient management. This article will discuss the pathologic features of acute and acute-on-chronic liver failure. Developing an appreciation for the histopathologic patterns of injury observed in these entities is essential for a practical understanding of the diagnostic process.