Setting up criteria for drug-induced autoimmune-like hepatitis through a systematic analysis of published reports

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.

EASL Clinical Practice Guidelines on the management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic liver disease of unknown aetiology which may affect any patient irrespective of age, sex, and ethnicity. At baseline, the clinical spectrum of the disease varies largely from asymptomatic cases to acute liver failure with massive hepatocyte necrosis. The aim of these EASL guidelines is to provide updated guidance on the diagnosis and management of AIH both in adults and children. Updated guidance on the management of patients with variants and specific forms of AIH is also provided, as is detailed guidance on the management of AIH-associated cirrhosis, including surveillance for portal hypertension and hepatocellular carcinoma, as well as liver transplantation in decompensated cirrhosis.

Histopathology of Autoimmune Hepatitis: An Update

Autoimmune hepatitis (AIH) is a rare immune-mediated chronic liver disease that is diagnosed based on a combination of biochemical, immunologic, and histologic features and the exclusion of other causes of liver disease. According to the new consensus criteria of the International Autoimmune Hepatitis Pathology Group (IAIHPG), the likely histologic features include a chronic hepatitis pattern of injury with a lymphoplasmacytic portal infiltrate, interface activity, and portal-based fibrosis. More than mild lobular hepatitis with any of the above features can also be diagnosed as likely AIH in the absence of features of another liver disease. Centrilobular injury with prominent hepatocellular necrosis and mononuclear inflammation may represent an acute-onset disease and indicate possible AIH in the absence of concurrent liver disease. Kupffer cell hyaline bodies and portal lymphocyte apoptosis are significantly associated with AIH, whereas emperipolesis and hepatocellular rosette formation are nonspecific features indicative of disease severity. Liver histology is an integral part of the clinical diagnostic scoring system and is required to confirm or support AIH diagnosis. Substitution of the histologic component of the simplified AIH scoring system with the consensus IAIHPG criteria has been proposed to optimize clinical diagnosis. This review explores the significant role of histopathology in AIH by analyzing its main features and current histologic diagnostic criteria, different AIH presentations, differential diagnosis, assessment of concurrent liver disease, and identification of AIH variants with primary cholangiopathy.

Clinicopathological characteristics of autoimmune‑like hepatitis after drug‑induced liver injury

Autoimmune hepatitis (AIH) can be induced by drugs, but the underlying mechanisms remain unclear. The present study attempted to elucidate the clinicopathological characteristics of autoimmune-like hepatitis following drug-induced liver injury (DILI-ALH). The medical records of 57 patients diagnosed with AIH at Mie General Medical Center (Yokkaichi, Japan) were retrospectively reviewed, paying particular attention to the history of drug administration. Patients were classified into three groups: De novo AIH, drug-induced ALH (DI-ALH) and DILI-ALH. DILI-ALH was newly defined as cases in which the patient had a history of DILI and where the liver injury initially improved after drug discontinuation, but later worsened and was diagnosed as AIH. Of the 57 patients diagnosed with AIH, 42 patients were included in this study. De novo AIH was diagnosed in 29 patients, DI-ALH in 10 patients and DILI-ALH in 3 patients. Suspected causative drugs for drug-related pathologies were variable, including statins, health foods and supplements. No significant differences in sex or mean age were observed for DI-ALH and DILI-ALH compared with those for AIH. Distinguishing DI-ALH or DILI-ALH from AIH serologically and pathologically is difficult. No significant differences in the number of steroids used or the recurrence rate were observed between any groups. These findings suggest that drugs may present a more diverse cause of ALH than generally predicted. In particular, some AIH cases clearly present with DILI-ALH. Clarifying the involvement of drugs in the pathogenesis of AIH and establishing guidelines for diagnosis and treatment represent important issues for the future.

Clinico-Pathological Spectrum of Hepatitis A Virus-Induced Autoimmune-Like Hepatitis in Children

There is limited evidence that hepatitis A virus (HAV) infection can trigger hepatic autoimmunity, but this area remains largely unexplored. This study was thus planned with the aim to compare HAV-induced autoimmune-like hepatitis (HAV-ALH) with HAV-related liver dysfunction (HAV-acute viral hepatitis or HAV-AVH) and classical autoimmune hepatitis (AIH). This was a retrospective review of 46 patients with HAV infection who underwent liver biopsy (including 17 cases of HAV-ALH: diagnosis based on histopathology), and they were compared to 46 cases of age- and gender-matched classical AIH. Overall, HAV cohort (n = 46) had higher prevalence of pruritus, higher bilirubin levels, higher proportion of cholestasis, lower IgG levels, higher seronegativity and lack of disease recurrence, while the classical AIH group had higher proportion/severity of interface hepatitis, fibrosis, necrosis and pseudorosetting (p < 0.05). In comparison to the classical HAV-AVH group, HAV-ALH group had higher AST levels, higher presence of autoantibodies, and higher prevalence of severe zone 3 perivenulitis and marked pseudorosetting on histology (p < 0.05). Also, HAV-ALH group, in comparison to the AIH group, had more pruritus (OR 7.29, p < 0.004) and more seronegativity (41% vs. 13%, p < 0.031), while duration of illness (p < 0.003), IgG (p < 0.001) levels and liver stiffness measurement (p < 0.006) were significantly higher in AIH group (versus the HAV-ALH and HAV-AVH groups). Histologically, in comparison to AIH, HAV-ALH group had significantly less interface hepatitis (OR 0.03, p < 0.001) and fibrosis (OR 0.08, p < 0.001) and significantly more cholestasis (OR 4.5, p < 0.021). HAV infection can act as a potential trigger for immune-mediated hepatic damage, akin to drug-induced autoimmune-like hepatitis. Larger multicentric studies are needed to further explore this aspect.

British Society of Gastroenterology guidelines for diagnosis and management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease which, if untreated, often leads to cirrhosis, liver failure and death. The last British Society of Gastroenterology (BSG) guideline for the management of AIH was published in 2011. Since then, our understanding of AIH has advanced in many areas. This update to the previous guideline was commissioned by the BSG and developed by a multidisciplinary group. The aim of this guideline is to review and summarise the current evidence, in order to inform and guide diagnosis and management of patients with AIH and its variant syndromes. The main focus is on AIH in adults, but the guidelines should also be relevant to older children and adolescents.

Liver Injury Following Intravenous Methylprednisolone Pulse Therapy in Multiple Sclerosis: The Experience from a Single Academic Liver Center

Intravenous methylprednisolone (IVMP) pulses, widely used for managing multiple sclerosis (MS) exacerbations, can lead to acute liver injury, presenting a diagnostic challenge in distinguishing between drug-induced autoimmune-like hepatitis (DI-ALH) and idiopathic autoimmune hepatitis (AIH). This study aimed to delineate the clinical and biochemical features of IVMP-induced liver injury, discern its etiology, and evaluate the efficacy of glucocorticoid (GC) therapy in treatment. A retrospective analysis of 13 relapsing MS patients with IVMP-induced liver injury was conducted. Liver injury was classified as hepatocellular, cholestatic, or mixed, with severity assessment guiding liver biopsy in selected cases. Causality was assessed using the Roussel Uclaf Causality Assessment Method (RUCAM) and the Simplified Diagnostic Criteria for AIH. All patients were initially monitored for a minimum of six months, with a mean follow-up period of 4.30 years. The median onset of liver injury was 37.46 days post-IVMP, with a mean peak alanine transaminase (ALT) level of 618.46 U/L. antinuclear antibody (ANA) positivity was observed in 61.53% of cases, with elevated serum immunoglobulin G (IgG) at 15.38%. Hepatocellular injury was universal among patients, and causality assessment predominantly supported DI-ALH. GC therapy was administered in six cases, achieving favorable outcomes in all but one, which necessitated rituximab. Biochemical normalization occurred within a mean of 55.41 days, with GC-treated patients recovering faster (48 days). These findings support the hypothesis that IVMP can induce hepatocellular injury, likely DI-ALH, during MS exacerbations. A tapering GC regimen proved effective in promoting recovery, particularly in severe cases. Additionally, this study introduced a diagnostic and therapeutic algorithm for managing IVMP-induced liver injury, offering a practical framework for clinical application.

Drug-Induced Liver Injury-Pharmacological Spectrum Among Children

Drug-induced liver injury (DILI) is one of the main causes of acute liver failure in children. Its incidence is probably underestimated, as specific diagnostic tools are currently lacking. Over 1000 known drugs cause DILI, and the list is expanding. The aim of this review is to describe DILI pathogenesis and emphasize the drugs accountable for child DILI in order to aid its recognition. Intrinsic DILI is well described in terms of mechanism, incriminated drugs, and toxic dose. Conversely, idiosyncratic DILI (iDILI) is unpredictable, occurring as a result of a particular response to drug administration, and its occurrence cannot be foreseen in clinical studies. Half of pediatric iDILI cases are linked to antibiotics, mostly amoxicillin-clavulanate, in the immune-allergic group, while autoimmune DILI is the hallmark of minocycline and nitrofurantoin. Secondly, antiepileptics are responsible for 20% of pediatric iDILI cases, children being more prone to iDILI caused by these agents than adults. A similar tendency was observed in anti-tuberculosis drugs, higher incidences being reported in children below three years old. Current data show growing cases of iDILI related to antineoplastic agents, atomoxetine, and albendazole, so that it is advisable for clinicians to maintain a high index of suspicion regarding iDILI.

Drug-induced autoimmune-like hepatitis: A disproportionality analysis based on the FAERS database

BACKGROUND

Drug-induced autoimmune-like hepatitis (DI-ALH) is a potentially life-threatening condition that can lead to acute liver failure and necessitate liver transplantation. While the association between certain drugs and DI-ALH has been documented, a comprehensive analysis of drug-related signals in a large, real-world pharmacovigilance database is lacking. This study aimed to systematically identify drugs linked to DI-ALH by analyzing adverse event reports from the U.S. Food and Drug Administration's (FDA) Adverse Event Reporting System (FAERS) database.

METHODS

We searched the FAERS database for the term "autoimmune hepatitis" and extracted DI-ALH reports from the first quarter of 2004 to the first quarter of 2024. Positive signal drugs were identified using Proportional Reporting Ratio (PRR), Reporting Odds Ratio (ROR), Bayesian Confidence Propagation Neural Network (BCPNN), and Empirical Bayesian Geometric Mean (EBGM). To confirm a significant drug-adverse event association, each method had to meet predefined thresholds: for PRR and ROR, values were considered significant if the lower 95% confidence interval (CI) was greater than 1 and at least three reports were identified; for BCPNN, an Information Component (IC025) greater than 0 indicated a signal; for EBGM, a value greater than 2 for the lower 95% confidence interval (EBGM05) was used to denote a positive signal.

RESULTS

A total of 5,723 DI-ALH reports were extracted from the FAERS database. Disproportionality analysis identified 50 drugs with strong associations to DI-ALH, with biologics, statins, antibiotics, and antiviral drugs representing the most common categories. Among these, nitrofurantoin (ROR 94.79, CI 78.53-114.41), minocycline (ROR 77.82, CI 65.09-93.05), and nivolumab (ROR 47.12, CI 15.06-147.39) exhibited the strongest signals. Additionally, several previously unreported drugs, including mesalazine, aldesleukin, onasemnogene abeparvovec-xioi, and nefazodone, were identified as having strong associations with DI-ALH. These findings were consistent across all four signal detection methods, further validating the robustness of the associations.

CONCLUSION

This study provides a comprehensive assessment of drugs associated with DI-ALH through a rigorous analysis of the FAERS database using multiple signal detection methods. By identifying both well-known and previously underreported drugs, this study contributes to a more complete understanding of drug-induced liver injury. The findings have important implications for pharmacovigilance strategies and clinical risk assessment. However, limitations inherent in the FAERS database, such as underreporting and the potential for reporting bias, should be considered. Further clinical validation is warranted to confirm these associations.

Autoimmune hepatitis associated with statins: a retrospective study of pharmacovigilance databases and review of the literature

BACKGROUND

Statin-associated autoimmune hepatitis (AIH) is a rare but potentially life-threatening adverse event. Currently, no studies have investigated the associationbetween AIH and different statins.

RESEARCH DESIGN AND METHODS

This retrospective analysis of statin-associated AIH utilized the FDA Adverse Event Reporting System (FAERS) database (Q1 2004 to Q1 2024) and a systematic literature review. Disproportionality and Bayesian analyses were used to detect potential AIH signals associated with statin use.

RESULTS

Among 3,581 AIH reports in the FAERS database, 337 (9.41%) were associated with statins. Among all statins, fluvastatin exhibited the strongest signal, with a relative odds ratio (ROR) of 54.85 (95% CI: 32.32-93.10). Stratified analysis revealed stronger signals in patients ≥65 years (ROR 16.83 vs 9.45) and females (ROR 13.88 vs 9.00) compared to patients <65 years and males, respectively. Statins showed a higher risk of AIH compared to evolocumab, and a similar or lower risk when compared to ezetimibe and fenofibrate. Additionally, 30 cases reported in 20 independent studies were summarized.

CONCLUSION

This study demonstrates a significant association between AIH and the use of statins, particularly among older patients and females. Further research is needed to explore additional risk factors for statin-associated AIH.

Protective and stochastic correlation between infectious diseases and autoimmune disorders

A priori, early exposure to a wide range of bacteria, viruses, and parasites appears to fortify and regulate the immune system, potentially reducing the risk of autoimmune diseases. However, improving hygiene conditions in numerous societies has led to a reduction in these microbial exposures, which, according to certain theories, could contribute to an increase in autoimmune diseases. Indeed, molecular mimicry is a key factor triggering immune system reactions; while it seeks pathogens, it can bind to self-molecules, leading to autoimmune diseases associated with microbial infections. On the other hand, a hygiene-based approach aimed at reducing the load of infectious agents through better personal hygiene can be beneficial for such pathologies. This review sheds light on how the evolution of the innate immune system, following the evolution of molecular patterns associated with microbes, contributes to our protection but may also trigger autoimmune diseases linked to microbes. Furthermore, it addresses how hygiene conditions shield us against autoimmune diseases related to microbes but may lead to autoimmune pathologies not associated with microbes.

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.

Serum markers for detecting histological features of autoimmune hepatitis and predicting prognosis in patients with antinuclear antibody‐positive drug‐induced liver injury

Aims

Although useful for distinguishing drug‐induced liver injury (DILI) from autoimmune hepatitis (AIH), liver biopsy is an invasive examination, and the presence of antinuclear antibody (ANA) positivity in patients with DILI could lead to excessive use of biopsy. Hence, we aimed to identify screening markers for histological features of AIH in patients with ANA‐positive DILI and verify their clinical outcomes after 1 year.

Methods

This retrospective study included patients with ANA‐positive DILI, who underwent liver biopsy between January 2017 and April 2022. Two pathologists identified histological features of AIH. We detected the independent indicators associated with histological features of AIH using logistic regression. We evaluated their diagnostic ability for histological features of AIH using the receiver operating characteristic curve. The follow‐up period to determine clinical outcomes was 1 year after DILI onset. The χ2 test or Fisher's exact test was used to compare categorical data and the Wilcoxon rank‐sum test was used to compare continuous variables. Two‐sided p < 0.05 was considered to indicate significance.

Results

The final analysis included 125 patients with ANA‐positive DILI, of whom 18 had AIH‐like histology. Factors independently associated with AIH‐like histology included globulin levels (odds ratio [OR] = 1.154, 95% confidence interval [CI] = 1.046–1.288; p = 0.006) and ANA titer ≥ 1:1000 (OR = 3.531, 95% CI = 1.136–11.303; p = 0.029). The optimal globulin cutoff indicating AIH‐like histology was 31.8 g/L. This globulin level in combination with ANA titer ≥ 1:1000 (area under the curve = 0.785, 95% CI = 0.738–0.832) provided a sensitivity of 100% and a specificity of 57% for indicating histological features of AIH in patients with ANA‐positive DILI. During follow‐up, more patients developed AIH in the group with AIH‐like histology than in the group without AIH‐like histology (35.3% vs. 0, p < 0.001).

Conclusions

For patients with ANA‐positive DILI and ANA titer ≥ 1:1000 or globulin ≥ 31.8 g/L, liver biopsy is recommended to determine the presence of histological features of AIH and guide further monitoring.

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.

Defining characteristics and long-term prognosis of drug-induced autoimmune-like hepatitis: A retrospective cohort study

BACKGROUND

Drug-induced autoimmune-like hepatitis (DI-AILH) is poorly defined and more data are required to better characterise and manage this disease entity.

OBJECTIVES

The aim of this study was to evaluate the clinical characteristics, histology and long-term outcomes of DI-AILH compared with idiopathic autoimmune hepatitis (AIH).

METHODS

This retrospective cohort study reviewed 28 DI-AILH and 39 AIH patients in a single centre. The new (2022) and simplified (2008) AIH histology criteria were used to assess DI-AILH.

RESULTS

DI-AILH were more likely to present with jaundice (p = 0.004) and higher bilirubin levels (p = 0.04) than AIH. AIH patients had higher rate of immunosuppression (IS) use including second- and third-line agents, though the time to reach biochemical remission were comparable. AIH patients had more advanced fibrosis than DI-AILH (Ishak fibrosis score 3.5 vs. 1.9, p < 0.0001). DI-AILH more commonly had eosinophilic aggregates (18% vs. 3%, p = 0.031) and less commonly showed plasma cell aggregates (61% vs. 97%, p < 0.001) than AIH. The simplified AIH histology criteria identified 1 atypical histology within the DI-AILH cohort, although this patient required long-term IS. The new AIH histology criteria classified 23 (82%) as likely AIH and 5 (18%) as possible AIH. Two of the possible DI-AILH did not require IS and one patient had successful IS withdrawal. Four DI-AILH patients with fibrosis stage ≤3 had successful IS withdrawal compared with none in the AIH group. Four patients underwent liver transplantation (LT) in both cohorts with significantly shorter time to LT in DI-AILH as the indication was for (sub)acute liver failure. Two DI-AILH patients died within 60 days of LT.

CONCLUSION

The new AIH histology criteria may be better at identifying DI-AILH. Immunosuppression withdrawal in those without significant fibrosis may be considered. DI-AILH is at risk of (sub)acute liver failure and early discussions with a transplant centre would be desirable.

Long-term outcomes of drug-induced autoimmune-like hepatitis after pulse steroid therapy

AIM

Pulse steroid therapy occasionally causes drug-induced autoimmune-like hepatitis (DI-ALH), but the long-term outcome of treated patients is not well known. In this study, we investigated the long-term outcomes of DI-ALH due to pulse steroid therapy.

METHODS

We retrospectively reviewed the medical records of 405 patients treated with pulse high-dose methylprednisolone in Kurashiki Central Hospital. The frequency and clinicopathological characteristics of acute liver injury that occurred within 3 months after the therapy were analyzed. The diagnosis of DI-ALH was made according to the revised international autoimmune hepatitis group criteria.

RESULTS

Among the 405 patients treated with methylprednisolone, 61 (15.1%) had acute liver injury after the pulse steroid therapy, and DI-ALH was diagnosed in five patients (1.2%). Absence of oral prednisolone tapering after the pulse steroid therapy was a significant risk factor for the subsequent development of DI-ALH (odds ratio 11.9; p = 0.017). One patient was treated with 3 days of intravenous methylprednisolone followed by oral prednisolone. Two patients were treated with glycyrrhizin followed by oral prednisolone due to ineffectiveness of glycyrrhizin. Remission was achieved with glycyrrhizin alone, and spontaneous remission without drug therapy occurred in one patient each. During the median follow-up period of 34 months, no relapse was evident in all the patients without maintenance therapy.

CONCLUSIONS

Pulse steroid therapy can cause DI-ALH, especially when subsequent prednisolone is not tapered. Prednisolone is effective for DI-ALH due to pulse steroid therapy, and can be safely withdrawn once remission is achieved.

Morphologic and molecular analysis of liver injury after SARS-CoV-2 vaccination reveals distinct characteristics

BACKGROUND & AIMS

Liver injury after COVID-19 vaccination is very rare and shows clinical and histomorphological similarities with autoimmune hepatitis (AIH). Little is known about the pathophysiology of COVID-19 vaccine-induced liver injury (VILI) and its relationship to AIH. Therefore, we compared VILI with AIH.

METHODS

Formalin-fixed and paraffin-embedded liver biopsy samples from patients with VILI (n = 6) and from patients with an initial diagnosis of AIH (n = 9) were included. Both cohorts were compared by histomorphological evaluation, whole-transcriptome and spatial transcriptome sequencing, multiplex immunofluorescence, and immune repertoire sequencing.

RESULTS

Histomorphology was similar in both cohorts but showed more pronounced centrilobular necrosis in VILI. Gene expression profiling showed that mitochondrial metabolism and oxidative stress-related pathways were more and interferon response pathways were less enriched in VILI. Multiplex analysis revealed that inflammation in VILI was dominated by CD8+ effector T cells, similar to drug-induced autoimmune-like hepatitis. In contrast, AIH showed a dominance of CD4+ effector T cells and CD79a+ B and plasma cells. T-cell receptor (TCR) and B-cell receptor sequencing showed that T and B cell clones were more dominant in VILI than in AIH. In addition, many T cell clones detected in the liver were also found in the blood. Interestingly, analysis of TCR beta chain and Ig heavy chain variable-joining gene usage further showed that TRBV6-1, TRBV5-1, TRBV7-6, and IgHV1-24 genes are used differently in VILI than in AIH.

CONCLUSIONS

Our analyses support that SARS-CoV-2 VILI is related to AIH but also shows distinct differences from AIH in histomorphology, pathway activation, cellular immune infiltrates, and TCR usage. Therefore, VILI may be a separate entity, which is distinct from AIH and more closely related to drug-induced autoimmune-like hepatitis.

IMPACT AND IMPLICATIONS

Little is known about the pathophysiology of COVID-19 vaccine-induced liver injury (VILI). Our analysis shows that COVID-19 VILI shares some similarities with autoimmune hepatitis, but also has distinct differences such as increased activation of metabolic pathways, a more prominent CD8+ T cell infiltrate, and an oligoclonal T and B cell response. Our findings suggest that VILI is a distinct disease entity. Therefore, there is a good chance that many patients with COVID-19 VILI will recover completely and will not develop long-term autoimmune hepatitis.

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.

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

BACKGROUND & AIMS

Idiosyncratic drug-induced liver injury (DILI) with autoimmune features is a liver condition with laboratory and histological characteristics similar to those of idiopathic autoimmune hepatitis (AIH), which despite being increasingly reported, remains largely undefined. We aimed to describe in-depth the features of this entity in a large series of patients from two prospective DILI registries.

METHODS

DILI cases with autoimmune features collected in the Spanish DILI Registry and the Latin American DILI Network were compared with DILI patients without autoimmune features and with an independent cohort of patients with AIH.

RESULTS

Out of 1,426 patients with DILI, 33 cases with autoimmune features were identified. Female sex was more frequent in AIH patients than in the other groups (p = .001). DILI cases with autoimmune features had significantly longer time to onset (p < .001) and resolution time (p = .004) than those without autoimmune features. Interestingly, DILI patients with autoimmune features who relapsed exhibited significantly higher total bilirubin and transaminases at onset and absence of peripheral eosinophilia than those who did not relapse. The likelihood of relapse increased over time, from 17% at 6 months to 50% 4 years after biochemical normalization. Statins, nitrofurantoin and minocycline were the drugs most frequently associated with this phenotype.

CONCLUSIONS

DILI with autoimmune features shows different clinical features than DILI patients lacking characteristics of autoimmunity. Higher transaminases and total bilirubin values with no eosinophilia at presentation increase the likelihood of relapse in DILI with autoimmune features. As the tendency to relapse increases over time, these patients will require long-term follow-up.

Research gaps and opportunities in autoimmune hepatitis-Results of the international autoimmune hepatitis group research workshop 2022

Autoimmune hepatitis (AIH) is a rare autoimmune liver disease that is characterised by a chronic inflammatory immune reaction directed against hepatocytes. The disease results in a substantial reduction in quality of life and potentially leads to liver-related complications or death. The International Autoimmune Hepatitis Group (IAIHG) initiated a series of research workshops to uncover the scientific gaps and opportunities in AIH. This review summarises the results of the latest workshop in Maastricht in 2022 and reviews the current challenges in adult AIH, particularly in relation to four important aspects of AIH: diagnostics; new immunomodulatory therapies; clinical trial design; and unmet clinical needs. This review also summarises the progress made since the AIH workshop in 2017. Patients and patient representatives were actively involved in the parallel working groups alongside clinicians and researchers. Despite 40 years of experience with diagnosing and treating AIH, false diagnoses occur and treatment is still based on nonselective immunosuppression. In addition to the need for more specific diagnostic tests, prognostic markers and tailor-based treatments, a major unmet clinical need was identified in areas of care delivery and health-related quality of life.

The Evolving Profile of Idiosyncratic Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is an infrequent but important cause of liver disease. Newly identified causes of DILI include the COVID vaccines, turmeric, green tea extract, and immune checkpoint inhibitors. DILI is largely a clinical diagnosis of exclusion that requires evaluation for more common causes of liver injury and a compatible temporal association with the suspect drug. Recent progress in DILI causality assessment includes the development of the semi-automated revised electronic causality assessment method (RECAM) instrument. In addition, several drug-specific HLA associations have been identified that can help with the confirmation or exclusion of DILI in individual patients. Various prognostic models can help identify the 5%-10% of patients at highest risk of death. Following suspect drug cessation, 80% of patients with DILI fully recover, whereas 10%-15% have persistently abnormal laboratory studies at 6 months of follow-up. Hospitalized patients with DILI with an elevated international normalized ratio or mental status changes should be considered for N-acetylcysteine therapy and urgent liver transplant evaluation. Selected patients with moderate to severe drug reaction with eosinophilia and systemic symptoms or autoimmune features on liver biopsy may benefit from short-term corticosteroids. However, prospective studies are needed to determine the optimal patients and dose and duration of steroids to use. LiverTox is a comprehensive, freely accessible Web site with important information regarding the hepatotoxicity profile of more than 1000 approved medications and 60 herbal and dietary supplement products. It is hoped that ongoing "omics" studies will lead to additional insight into DILI pathogenesis, improved diagnostic and prognostic biomarkers, and mechanism-based treatments.

Drug-Induced Liver Injury due to Biologics and Immune Check Point Inhibitors

Biological agents have in the last two decades become very important therapeutic agents, particularly for the treatment of various autoimmune disorders. The most widely used biologics are the tumor necrosis factor-α (TNF-α) receptor antagonists: infliximab, adalimumab, and etanercept. Other commonly used biological agents are interleukin (IL)-1 receptor antagonist (Anakinra), interleukin (IL)-6 receptor antagonist (tocilizumab), and CD20 surface antigen antagonist (rituximab). The current review will however focus on TNF-α receptor antagonists.

Clinical features, outcomes, and HLA risk factors associated with nitrofurantoin-induced liver injury

BACKGROUND & AIMS

Nitrofurantoin (NTF) is widely used for the treatment (short-term) and prevention (long-term) of urinary tract infections. We aimed to describe the clinical characteristics, outcomes, and HLA risk factors for NTF-induced liver injury (NTF-DILI) among individuals enrolled in the Drug Induced Liver Injury Network (DILIN).

METHODS

Seventy-eight individuals with definite, highly likely, or probable NTF-DILI were enrolled into DILIN studies between 2004-2020. HLA alleles were compared between NTF-DILI and three control groups: population (n = 14,001), idiopathic autoimmune hepatitis (n = 231), and non-NTF DILI (n = 661).

RESULTS

Liver injury was hepatocellular in 69% and icteric in 55%. AST > ALT was more common in the 44 long-exposure (≥1 year) NTF-DILI cases than in the 18 short (≤7 days) and 16 intermediate (>7 to <365 days) exposure cases (73% vs. 33% vs. 50%, respectively, p = 0.018), as was ANA or SMA positivity (91% vs. 44% vs. 50%, respectively, p <0.001), and corticosteroid use (61% vs. 27% vs. 44%, respectively, p = 0.06). In long-term NTF-DILI, bridging fibrosis, nodularity or cirrhosis, or clinical and imaging evidence for cirrhosis were present in 38%, with massive or sub-massive necrosis in 20%. No one in the short-term exposure group died or underwent transplantation, whereas 7 (12%) patients from the other groups died or underwent transplantation. After covariate adjustments, HLA-DRB1∗11:04 was significantly more frequent in NTF-DILI compared to population controls (odds ratio [OR] 4.29, p = 1.15 × 10-4), idiopathic autoimmune hepatitis (OR 11.77, p = 7.76 × 10-5), and non-NTF DILI (OR 3.34, p = 0.003).

CONCLUSION

NTF-DILI can result in parenchymal necrosis, bridging fibrosis, cirrhosis, and death or liver transplantation, especially with long-term exposure, and is associated with HLA-DRB1∗11:04. To mitigate against serious liver injury associated with NTF, regulators should revise the prescribing information and consider other mitigation strategies.

IMPACT AND IMPLICATIONS

Nitrofurantoin is a recognized cause of drug-induced liver injury (DILI). In this study consisting of a large cohort of well-phenotyped individuals with nitrofurantoin-induced liver injury, two distinct patterns of liver injury were identified: liver injury associated with short-term exposure, which is generally self-limiting, and liver injury associated with long-term exposure, which can lead to advanced fibrosis, cirrhosis and liver failure. HLA DRB1∗11:04 is a risk factor for liver injury due to long-term nitrofurantoin exposure. Our findings are important for regulators as well as physicians prescribing and pharmacists dispensing nitrofurantoin.

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.

Recreational Drugs and the Risk of Hepatocellular Carcinoma

Recreational or aesthetic drug use is a distinctive behavior of humans, principally attested in the last century. It is known that recreational and illegal drugs are major contributors to the universal morbidity rate worldwide. Many of these substances have a well-established hepatotoxic potential, causing acute or chronic liver injury, liver fibrosis and cirrhosis, but their implications for hepatocellular carcinoma or other varieties of liver tumors are little known. In this article, we perform an extensive literature review, aiming to provide updated information about recreational drug use and the risk of developing liver tumors. Khat use and pyrrolizidine alkaloid consumption (present in some natural plants) have been linked to liver cirrhosis. Kava intake is associated with different liver tumors in animal models but not in humans. Cannabis' potential to accelerate liver fibrosis in chronic hepatitis is controversial according to the existing data. Cigarette smoking is an important contributor to hepatocellular carcinoma, and anabolic androgen steroids are well-defined causes of a variety of liver cancers and other hepatic tumors. Long-term follow-up studies of subjects who have developed injuries in association with the use of recreational drugs are warranted so as to better define the risk of developing hepatocellular carcinoma in association with these substances and, thus, to implement health care policies to combat this preventable cause of cancer.