The Asian Pacific Association for the Study of the Liver clinical practice guidance: the diagnosis and management of patients with autoimmune hepatitis

Comprehensive analysis of immune signatures in primary biliary cholangitis and autoimmune hepatitis

Primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH) are autoimmune diseases that target hepatocytes and bile duct cells, respectively. Despite their shared autoimmune nature, the differences in immunologic characteristics between them remain largely unexplored. This study seeks to elucidate the unique immunological profiles of PBC and AIH and to identify key differences. We comprehensively analyzed various T cell subsets and their receptor expression in a cohort of 45 patients, including 27 PBC and 18 AIH cases. Both diseases exhibited T cell exhaustion and senescence along with a surge in inflammatory cytokines. Significantly increased CD38+HLA-DR+CD8+ T cell populations were observed in both diseases. AIH was characterized by an upregulation of CD8+ terminally differentiated T, CD4+ effector memory T, and CD4+ terminally differentiated T cells, and a concurrent reduction in regulatory T cells. In contrast, PBC displayed a pronounced presence of T follicular helper (Tfh) cells and a contraction of CD4-CD8- T cell populations. Correlation analysis revealed that NKP46+ natural killer frequency was closely tied to alanine aminotransferase and aspartate aminotransferase levels, and TIGIT expression on T cells was associated with globulin level in AIH. In PBC, there is a significant correlation between Tfh cells and ALP levels. Moreover, the identified immune landscapes in both diseases strongly related to disease severity. Through logistic regression analysis, γδ T, TIGIT+Vδ2 T, and Tfh1 cell frequencies emerged as distinct markers capable of differentiating PBC from AIH. In conclusion, our analyses reveal that PBC and AIH share similarities and differences regarding to immune profiles. γδ T, TIGIT+Vδ2 T, and Tfh1 cell frequencies are potential noninvasive immunological markers that can differentiate PBC from AIH.

Acute presentation of autoimmune hepatitis -from acute hepatitis to ALF and ACLF

Acute presentation of autoimmune hepatitis (AIH) occurs in 22-43% of all AIH cases, and is not a rare condition. Rather than constituting a single disease entity, it represents a clinical spectrum characterized by considerable variability in severity and the presence of preexisting chronic AIH. This spectrum ranges from acute AIH and acute severe AIH to AIH presenting as acute liver failure (ALF) or as acute-on-chronic liver failure (ACLF), contingent upon factors such as coagulopathy, hepatic encephalopathy, and underlying liver disease. Diagnosing acute presentation of AIH can be particularly challenging due to the frequent absence of classical serologic signatures such as autoantibodies and elevated IgG levels. Histopathological examination remains essential for diagnosis, typically necessitating percutaneous or transjugular liver biopsy. Corticosteroids (CS) are recommended for the management of acute AIH and acute severe AIH with coagulopathy. However, the therapeutic response to CS should be meticulously monitored. If a poor response is anticipated, liver transplantation (LT) should be promptly considered. For AIH presenting as ALF with encephalopathy or ACLF with advanced underlying liver disease, LT is generally advised. Nonetheless, there is potential for a trial of CS therapy in cases of ALF with low MELD scores or ACLF without encephalopathy. This review provides an overview of the latest findings concerning the definition, diagnosis, and management of acute presentation of AIH.

Liver fibrosis is closely linked with metabolic-associated diseases in patients with autoimmune hepatitis

BACKGROUND

This cross-sectional study aimed to investigate the impact of metabolic-associated diseases (MADs) on patients with autoimmune hepatitis (AIH).

METHODS

The study analyzed the clinical characteristics of 283 AIH patients who underwent liver biopsy between January 2016 and February 2022 in Ruijin Hospital, Shanghai, China.

RESULTS

Among the identified AIH patients (n = 283), 87.3%, 23.0%, or 43.1% had MADs, non-alcoholic fatty liver disease (NAFLD), or severe fibrosis, respectively. The proportion of diabetes mellitus (DM) was significantly higher in patients with severe liver fibrosis than in those with mild or moderate fibrosis in the AIH cohort (31.1% vs. 18.0%, p < 0.05). Fibrosis was also more severe in patients with NAFLD than in those without (53.8% vs. 39.9%, p < 0.05). Age, Plts, IgG and the presence with MADs were identified as independent predictors of the severity of inflammation in AIH patients. Moreover, severe liver fibrosis (stages 3 to 4) was independently associated with male (OR, 2.855; p = 0.025), γ-GT (OR, 0.997; p = 0.007), and combination with MADs (OR, 4.917; p = 0.006). Furthermore, combination with DM was also an independent predictor of severe liver fibrosis in AIH patients (OR, 2.445, p = 0.038).

CONCLUSIONS

Concurrent MADs, common in AIH patients, is an independent risk factor for severe fibrosis or inflammation; of note, combination with DM was also an independent predictor of severe liver fibrosis in AIH patients. While managing with AIH, routine assessment of co-existing MADs, especially DM, is also important.

Efficacy and safety of infliximab in patients with autoimmune hepatitis

BACKGROUND AND AIMS

A limited number of drugs are used as standard or alternative therapies in autoimmune hepatitis (AIH). No specific recommendations are available for patients failing to respond to these therapies. We analyzed the efficacy and safety of infliximab in patients with AIH.

APPROACH AND RESULTS

We performed a retrospective study of 42 patients with AIH who received infliximab at 21 liver centers in 12 countries. Patients were categorized according to the reason for infliximab therapy. Patients in group 1 (n=20) had failed standard, second-line (mycophenolate mofetil and 6-mercaptopurine) or third-line (tacrolimus or cyclosporine) therapy. In group 2 (n=22), infliximab was given for treatment of concomitant extrahepatic autoimmune diseases. Patients received a median of 17 (range: 3-104) infliximab infusions. Complete biochemical response (CR) was achieved or maintained in 33 (78%) patients during infliximab therapy. In group 1, infliximab induced CR in 11 of 20 (55%) patients. In group 2, 16 patients with CR prior to infliximab maintained remission, and the remaining 6 patients with active AIH (5 on standard and 1 on both second-line and third-line therapy) showed CR following infliximab therapy. Infliximab led to CR in 75% (6/8) of nonresponders to second-line and in 46% (6/13) of failing third-line therapy. Overall, 65% (17/26) of the patients with active AIH achieved CR on infliximab. Infliximab was discontinued in 3 patients of group 1. One patient had a severe allergic reaction and 2 developed anti-infliximab autoantibodies.

CONCLUSIONS

Our study suggests that infliximab may be an effective and safe rescue therapy in AIH.

The Impact of Histologic Portal T-Cell Density on the Clinical Outcomes in Hepatic Graft-versus-Host Disease and Autoimmune Liver Diseases

Hepatic graft-versus-host disease (GVHD) significantly impacts morbidity and mortality among allogeneic hematopoietic stem cell transplant recipients. However, the relationship between clinical and immunopathological phenotypes and their influence on clinical outcomes in hepatic GVHD is not well understood. In this study, we aimed to study the implications of portal T-cell infiltration on the clinical outcomes in hepatic GHVD and its similarities to autoimmune liver disease. We analyzed 78 patients with biopsy-confirmed hepatic GVHD (n = 38) or autoimmune liver disease (n = 40) between 2016 and 2021. The cholestatic variant was defined by an R-value < 2.0, based on the ratio of alanine aminotransferase to alkaline phosphatase. The primary outcome was the biochemical response at 4 (early) and 8-12 (late) weeks after corticosteroid treatment. In hepatic GVHD patients, the hepatitic variant (n = 19) showed greater CD3+ T-cell infiltration than the cholestatic variant (n = 19; p < 0.001). No significant differences were observed in the infiltration of CD20+, CD38+, or CD68+ cells. The hepatitic variant had significantly better early and late responses and higher liver-related event-free survival than the cholestatic variants (p < 0.05). Concerning autoimmune liver diseases, the autoimmune hepatitis (AIH) group had significantly more portal T-cell infiltration and better treatment responses than the primary biliary cholangitis (PBC) group. In conclusion, higher portal T-cell infiltration may be associated with better clinical outcomes in patients with hepatic GVHD. Additionally, this study highlights similarities in portal T-cell infiltration and treatment response patterns between AIH and the hepatitic variant, as well as PBC and the cholestatic variant.

Drug-induced liver injury associated with savolitinib: a novel case report and causality assessment

BACKGROUND

Savolitinib, a small molecule inhibitor, has gained approval as the inaugural medication in China that specifically targets MET kinase. Patients with advanced non-small cell lung cancer (NSCLC) who show MET exon 14 skipping now have a new and innovative treatment option available.

CASE REPORT

In this case report, we describe a patient who experienced drug-induced liver injury (DILI) due to the administration of savolitinib. After being prescribed with savolitinib (400 mg per day, oral), a 73-year-old male diagnosed with stage IV NSCLC with MET exon 14 skipping mutation experienced an increase in liver enzymes and bilirubin levels according to his laboratory tests conducted one month later. Following a 14-day course of hepatoprotective medication, the liver function reverted back to its normal state. After receiving savolitinib (200 mg per day, oral) for one week, the patient was once again diagnosed with severe liver impairment. Then savolitinib was discontinued and received treatment with hepatoprotective drugs for one week. Following the restoration of normal liver function, another attempt was made to administer a small amount of savolitinib (100 mg per day, oral). Thus far, the patient has been followed up and there has been no recurrence of liver damage. Additionally, the lung CT scan revealed ongoing tumor shrinkage with no apparent indications of spreading or metastasis. The Roussel Uclaf Causality Assessment Method (RUCAM) determined that savolitinib was "highly probable" cause of DILI. Moderate-severe was determined to be the extent of DILI severity.

CONCLUSION

To the best of our understanding, this is the initial instance of DILI resulting from the use of savolitinib as a standalone treatment in a real-world setting. During the administration of savolitinib, healthcare professionals should carefully consider the potential occurrence of DILI. Administering the patient with a small amount of savolitinib resulted in a remarkable response against the tumor, leading us to speculate that the effectiveness of savolitinib might be associated with its plasma concentration. Studying the pharmacokinetics and pharmacodynamics (PK/PD) of savolitinib is beneficial for tailoring and accurately prescribing the medication to each individual.

An optimized short-term steroid therapy for chronic drug-induced liver injury: A prospective randomized clinical trial

BACKGROUND AND AIMS

The use of corticosteroids in chronic drug-induced liver injury (DILI) is an important issue. Our previous randomized controlled trial showed that patients with chronic DILI benefited from a 48-week steroid stepwise reduction (SSR) regimen. However, it remains unclear whether a shorter course of therapy can achieve similar efficacy. In this study, we aimed to assess whether a 36-week SSR can achieve efficacy similar to that of 48-week SSR.

METHODS

A randomized open-label trial was performed. Eligible patients were randomly assigned to the 36- or 48-week (1:1) SSR group. Liver biopsies were performed at baseline and at the end of treatment. The primary outcome was the proportion of patients with relapse rate (RR). The secondary outcomes were improvement in liver histology and safety.

RESULTS

Of the 90 participants enrolled, 84 (87.5%) completed the trial, and 62 patients (68.9%) were women. Hepatocellular damage was observed in 53.4% of the cohort. The RR was 7.1% in the 36-week SSR group but 4.8% in the 48-week SSR group, as determined by per-protocol set analysis (p = 1.000). Significant histological improvements in histological activity (93.1% vs. 92.9%, p = 1.000) and fibrosis (41.4% vs. 46.4%, p = .701) were observed in both the groups. Biochemical normalization time did not differ between the two groups. No severe adverse events were observed.

CONCLUSIONS

Both the 36- and 48-week SSR regimens demonstrated similar biochemical response and histological improvements with good safety, supporting 36-week SSR as a preferable therapeutic choice (ClinicalTrials.gov, NCT03266146).

Liver inflammation activity in patients with autoimmune hepatitis with normal alanine aminotransferase and immunoglobulin G levels

Background and aims

Normal serum transaminases and immunoglobulin G (IgG) levels are surrogate markers for hepatic histologic disease activity in autoimmune hepatitis (AIH). This study aimed to evaluate liver inflammation in patients with AIH with normal serum alanine aminotransferase (ALT) and IgG levels.

Methods

Two hundred and five AIH patients who underwent liver biopsy in four medical centers were included. Logistic regression analysis was used to identify risk factors associated with advanced inflammation.

Results

One hundred and thirty-one (63.9 %) AIH patients had advanced liver inflammation, and 108 (52.7 %) patients had advanced liver fibrosis. 60.0 % of patients with normal ALT and 51.7 % of patients with normal ALT and IgG had advanced inflammation. However, 76.7 % and 35.0 % of patients with or without advanced fibrosis with normal ALT had advanced inflammation, while the corresponding proportions of advanced inflammation were 78.6 % and 26.7 % in patients with normal ALT and IgG, respectively. Moreover, 81.0 % and 44.8 % of patients with and without cirrhosis with normal ALT had advanced inflammation, while the corresponding proportions were 83.3 % and 29.4 % in patients with normal ALT and IgG, respectively. Red cell distribution width (OR = 1.325, 95%CI 1.045-1.681, P = 0.020) and PT (OR = 1.514, 95%CI 1.138-2.014, P = 0.004) were independent factors associated with advanced inflammation.

Conclusions

High proportion of advanced inflammation was found in AIH patients with normal ALT and IgG levels despite without advanced fibrosis. Although using non-invasive methods may contribute to rule out liver fibrosis in AIH patients with normal ALT and IgG levels, liver biopsy is encouraged to assess liver inflammation.

The frequency and clinical significance of antibodies to soluble liver antigen/liver pancreas in autoimmune hepatitis: a prospective single-center study

BACKGROUND AND AIMS

Soluble liver antigen/liver pancreas antibodies (anti-SLA/LP) are specific markers for autoimmune hepatitis (AIH) that have been associated with a distinct clinical phenotype and a more aggressive form of AIH. We prospectively evaluated the frequency and clinical significance of anti-SLA/LP in Turkish patients with AIH.

MATERIAL AND METHODS

We prospectively included patients diagnosed with AIH between January 2018 and May 2023. Autoantibodies were detected using by immunofluorescence and immunoblot.

RESULTS

We included 61 (80%, female) AIH patients with a median age of 31 years (15-78) at the time of diagnosis. Anti-SLA/LP was detected in 20% ( n  = 12) of the patients. Baseline characteristics, treatment responses and outcomes were similar among anti-SLA/LP-positive and anti-SLA/LP-negative AIH patients. Anti-SLA/LP-positive patients had significantly higher biochemical response rates after 4 weeks (100 vs. 67%, P  = 0.027), 3 months (100 vs. 39%, P  < 0.001), 6 months (100 vs. 69%, P  = 0.041) of therapy but not after 12 months (100 vs. 76%, P  = 0.103) and at the end of follow-up (100 vs. 91%, P  = 0.328). Relapse rates following treatment response were similar in patients with and without anti-SLA/LP (22 vs. 23%, P  = 0.956). Second-line therapies (tacrolimus and mycophenolate mofetil) were given to seven (11%) patients, all were anti-SLA/LP-negative. Two of these progressed into end-stage liver disease and both underwent liver transplantation.

CONCLUSION

Our study results suggest that anti-SLA/LP positivity does not entail clinically distinct or severe features in AIH. In our cohort, anti-SLA/LP-positive patients showed a quicker response to immunosuppressive therapy.

Insights into the Management of Chronic Hepatitis in Children-From Oxidative Stress to Antioxidant Therapy

Recent research has generated awareness of the existence of various pathophysiological pathways that contribute to the development of chronic diseases; thus, pro-oxidative factors have been accepted as significant contributors to the emergence of a wide range of diseases, from inflammatory to malignant. Redox homeostasis is especially crucial in liver pathology, as disturbances at this level have been linked to a variety of chronic diseases. Hepatitis is an umbrella term used to describe liver inflammation, which is the foundation of this disease regardless of its cause. Chronic hepatitis produces both oxidative stress generated by hepatocyte inflammation and viral inoculation. The majority of hepatitis in children is caused by a virus, and current studies reveal that 60-80% of cases become chronic, with many young patients still at risk of advancing liver damage. This review intends to emphasize the relevance of understanding these pathological redox pathways, as well as the need to update therapeutic strategies in chronic liver pathology, considering the beneficial effects of antioxidants.

Implications of Gender on the Outcome in Patients With Autoimmune Hepatitis

BACKGROUND

Autoimmune hepatitis (AIH) is uncommon and predominantly affects females. Data on AIH from India are scanty. We retrospectively analyzed the spectrum and outcome of adults with AIH and compared it between male and female patients.

METHODS

AIH was diagnosed using a simplified AIH score. For suspected seronegative AIH, the revised score was used. Standard therapies for AIH and portal hypertension were administered and response was assessed at six months. Relapse rates and five-year mortality were also evaluated.

RESULTS

Of the 157 patients with AIH, 85 (male: female 25: 60) were included in the study. The median age at diagnosis was 46 (interquartile range (IQR) 32-55.5) years in males vs 45 (IQR 34.2-54) years in females (p=0.91). A similar proportion of male and female patients presented with cirrhosis, acute severe AIH, or AIH-related acute on chronic liver failure (ACLF); Extra-hepatic autoimmune diseases were less common in male patients (16% vs 35.5% p=0.02). Other laboratory and histological features were comparable in both groups. During the median follow-up period of 51 months (IQR 45-67 months). The biochemical and clinical response at six months were seen in 64% of male patients and 63.3% of female patients (p= 0.57). Of patients, 75% relapsed in the male AIH group (12 of 16 patients) after initial remission compared to 42% in the female group (p=0.02). Five-year mortality was 14.1%, and no patient developed hepatocellular carcinoma.

CONCLUSION

Male and female patients with AIH have similar clinical, biochemical, and histological profiles. More male patients relapsed after an initial response to therapy.

Advancements in autoimmune hepatitis management: Perspectives for future guidelines

The first-line treatment for autoimmune hepatitis involves the use of prednisone or prednisolone either as monotherapy or in combination with azathioprine (AZA). Budesonide has shown promise in inducing a complete biochemical response (CBR) with fewer adverse effects and is considered an optional first-line treatment, particularly for patients without cirrhosis; however, it is worth noting that the design of that study favored budesonide. A recent real-life study revealed higher CBR rates with prednisone when equivalent initial doses were administered. Current guidelines recommend mycophenolate mofetil (MMF) for patients who are intolerant to AZA. It is important to mention that the evidence supporting this recommendation is weak, primarily consisting of case series. Nevertheless, MMF has demonstrated superiority to AZA in the context of renal transplant. Recent comparative studies have shown higher CBR rates, lower therapeutic failure rates, and reduced intolerance in the MMF group. These findings may influence future guidelines, potentially leading to a significant modification in the first-line treatment of autoimmune hepatitis. Until recently, the only alternative to corticosteroids was lifelong maintenance treatment with AZA, which comes with notable risks, such as skin cancer and lymphoma. Prospective trials are essential for a more comprehensive assessment of treatment suspension strategies, whether relying on histological criteria, strict biochemical criteria, or a combination of both. Single-center studies using chloroquine diphosphate have shown promising results in significantly reducing relapse rates compared to placebo. However, these interesting findings have yet to be replicated by other research groups. Additionally, second-line drugs, such as tacrolimus, rituximab, and infliximab, should be subjected to controlled trials for further evaluation.

STING modulates iron metabolism to promote liver injury and inflammation in acute immune hepatitis

The pathogenesis of Autoimmune Hepatitis (AIH) is closely associated with perturbations in iron ion metabolism, during which Stimulator of Interferon Genes (STING) plays an important role. However, the precise regulatory mechanism remains elusive. In this study, we investigated the relationship between iron dysregulation and STING activation in Concanavalin A (ConA)-induced AIH liver injury. STING knockout (STING-/-) mice and AAV (Adeno-Associated virus)-Sting1-RNAi-treated mice were involved and subjected in AIH. We observed that increased iron dysregulation was linked with STING activation, but this effect was effectively reversed by the administration of iron chelating agent Desferoxamine (DFO) and the antioxidant Ferrostatin-1 (Fer-1). Notably, the iron transport protein Transferrin (TF) and Transferrin Receptor (TfR) exhibited significant accumulation in AIH along with upregulated expression of ferritin protein. Additionally, the deficiency of STING reduced hepatic iron accumulation, mitigated oxidative stress, and attenuated macrophage activation during ConA treatment. Furthermore, liver-specific knockdown of STING using AAV-Sting1-RNAi significantly ameliorated liver iron dysregulation and oxidative stress response induced by Kupffer cells (KCs). KC-derived STING exacerbates liver damage severity in AIH through promoting disturbances in hepatic iron ion metabolism as well as oxidative stress response. These findings provide valuable insights into the pathogenesis of AIH and may pave the way for potential therapeutic strategies targeting STING and iron metabolism in the future.

Unveiling the interplay between NSAID-induced dysbiosis and autoimmune liver disease in children: insights into the hidden gateway to autism spectrum disorders. Evidence from ex vivo, in vivo, and clinical studies

Autism spectrum disorders (ASD) represent a diverse group of neuropsychiatric conditions, and recent evidence has suggested a connection between ASD and microbial dysbiosis. Immune and gastrointestinal dysfunction are associated with dysbiosis, and there are indications that modulating the microbiota could improve ASD-related behaviors. Additionally, recent findings highlighted the significant impact of microbiota on the development of autoimmune liver diseases, and the occurrence of autoimmune liver disease in children with ASD is noteworthy. In the present study, we conducted both an in vivo study and a clinical study to explore the relationship between indomethacin-induced dysbiosis, autoimmune hepatitis (AIH), and the development of ASD. Our results revealed that indomethacin administration induced intestinal dysbiosis and bacterial translocation, confirmed by microbiological analysis showing positive bacterial translocation in blood cultures. Furthermore, indomethacin administration led to disturbed intestinal permeability, evidenced by the activation of the NLRP3 inflammasomes pathway and elevation of downstream biomarkers (TLR4, IL18, caspase 1). The histological analysis supported these findings, showing widened intestinal tight junctions, decreased mucosal thickness, inflammatory cell infiltrates, and collagen deposition. Additionally, the disturbance of intestinal permeability was associated with immune activation in liver tissue and the development of AIH, as indicated by altered liver function, elevated ASMA and ANA in serum, and histological markers of autoimmune hepatitis. These results indicate that NSAID-induced intestinal dysbiosis and AIH are robust triggers for ASD existence. These findings were further confirmed by conducting a clinical study that involved children with ASD, autoimmune hepatitis (AIH), and a history of NSAID intake. Children exposed to NSAIDs in early life and complicated by dysbiosis and AIH exhibited elevated serum levels of NLRP3, IL18, liver enzymes, ASMA, ANA, JAK1, and IL6. Further, the correlation analysis demonstrated a positive relationship between the measured parameters and the severity of ASD. Our findings suggest a potential link between NSAIDs, dysbiosis-induced AIH, and the development of ASD. The identified markers hold promise as indicators for early diagnosis and prognosis of ASD. This research highlights the importance of maintaining healthy gut microbiota and supports the necessity for further investigation into the role of dysbiosis and AIH in the etiology of ASD.

Advances in Understanding and Managing Autoimmune Hepatitis: A Narrative Review

Autoimmune hepatitis (AIH) is a chronic liver disease characterized by immune-mediated destruction of hepatocytes, leading to inflammation and fibrosis. In recent years, significant advances have been made in understanding the pathogenesis, epidemiology, diagnosis, and treatment of AIH. This comprehensive narrative review aims to provide an up-to-date overview of these advances. The review begins by outlining the historical background of AIH, dating back to its initial recognition in the 1940s, and highlights the evolution of diagnostic criteria and classification based on autoantibody profiles. The epidemiology of AIH is explored, discussing its varying prevalence across different regions and the role of genetic predisposition, viral infections, and drug exposure as risk factors. Furthermore, the review delves into the pathogenesis of AIH, focusing on the dysregulated immune response, involvement of T cells, and potential contribution of the gut microbiome. Clinical presentation, diagnostic criteria, and liver biopsy as crucial tools for diagnosis are also discussed. Regarding management, the review provides an in-depth analysis of the standard first-line treatments involving glucocorticoids and azathioprine, as well as alternative therapies for non-responsive cases. Additionally, emerging second and third-line treatment options are examined. In conclusion, this narrative review highlights the complexity of AIH and underscores the importance of early diagnosis and individualized treatment approaches to improve patient outcomes. Further research and clinical trials are needed to optimize AIH management and ensure a better long-term prognosis for affected individuals.

Infections after organ transplantation and immune response

Organ transplantation has provided another chance of survival for end-stage organ failure patients. Yet, transplant rejection is still a main challenging factor. Immunosuppressive drugs have been used to avoid rejection and suppress the immune response against allografts. Thus, immunosuppressants increase the risk of infection in immunocompromised organ transplant recipients. The infection risk reflects the relationship between the nature and severity of immunosuppression and infectious diseases. Furthermore, immunosuppressants show an immunological impact on the genetics of innate and adaptive immune responses. This effect usually reactivates the post-transplant infection in the donor and recipient tissues since T-cell activation has a substantial role in allograft rejection. Meanwhile, different infections have been found to activate the T-cells into CD₄⁺ helper T-cell subset and CD₈⁺ cytotoxic T-lymphocyte that affect the infection and the allograft. Therefore, the best management and preventive strategies of immunosuppression, antimicrobial prophylaxis, and intensive medical care are required for successful organ transplantation. This review addresses the activation of immune responses against different infections in immunocompromised individuals after organ transplantation.

[Treatment of Autoimmune Hepatitis]

Autoimmune hepatitis (AIH) is a chronic liver disease, characterized by elevated levels of transaminases, immunoglobulin G, and positive autoantibodies. The disease course is dynamic and presents heterogeneous disease manifestations at diagnosis. This review summarizes the issues regarding the treatment and monitoring of AIH in adult patients. Glucocorticoids and azathioprine are the first line of treatment. Alternative first-line treatments include budesonide or mycophenolate mofetil (MMF). Although no randomized controlled trials have been performed, MMF, cyclosporine, tacrolimus, 6-mercaptopurine, 6-thioguanine, allopurinol, sirolimus, everolimus, infliximab, or rituximab have been attempted in patients not responding to or intolerant to first-line treatments. Most patients require life-long special monitoring, with or without maintenance treatment.

[Diagnosis of Autoimmune Hepatitis]

Autoimmune hepatitis (AIH) is an immune-mediated inflammatory liver disease with an uncertain cause. The diagnosis of AIH is based on the characteristic clinical and laboratory findings (elevated liver enzyme and hypergammaglobulinemia), the presence of characteristic autoantibodies, and compatible histological abnormalities. AIH lacks a signature diagnostic marker, and the diagnosis requires the exclusion of other diseases (viral hepatitis, alcoholic liver disease, non-alcoholic steatohepatitis, drug-induced liver injury, Wilson's disease, and hereditary hemochromatosis). Therefore, collaboration between the clinical physician, laboratory medicine experts, and pathologists is important for a diagnosis. In December 2022, the Korean Association for the Study of the Liver (KASL) clinical practice guidelines were established. This review article summarizes the diagnosis part of these guidelines.

Diagnosis and management of autoimmune hepatitis

Autoimmune hepatitis is an inflammatory disease of the liver of unknown cause that may progress to liver cirrhosis and end stage liver failure if diagnosis is overlooked and treatment delayed. The clinical presentation is often that of acute hepatitis, sometimes very severe; less frequently, it can be insidious or completely asymptomatic. The disease can affect people of any age and is more common in women; its incidence and prevalence seem to be on the rise worldwide. An abnormal immune response targeting liver autoantigens and inducing persistent and self-perpetuating liver inflammation is the pathogenic mechanism of the disease. A specific set of autoantibodies, increased IgG concentrations, and histological demonstration of interface hepatitis and periportal necrosis are the diagnostic hallmarks of autoimmune hepatitis. Prompt response to treatment with corticosteroids and other immunomodulatory drugs is almost universal and supports the diagnosis. The aims of treatment are to induce and maintain long term remission of liver inflammation. Treatment can often even reverse liver fibrosis, thus preventing progression to advanced cirrhosis and its complications. Most patients need lifelong maintenance therapy, and repeated follow-up in experienced hands improves the quality of care and quality of life for affected patients.

The many faces and pathologic diagnostic challenges of autoimmune hepatitis

Autoimmune hepatitis (AIH) is an immune-mediated chronic inflammatory liver disease, characterized by hypergammaglobulinemia, the presence of specific autoantibodies, and typical abnormalities in liver histology. Prompt diagnosis and initiation of immunosuppressive treatment are necessary for both chronic and acute onset AIH to prevent progression to end-stage liver disease or fatal liver failure. However, the diagnosis of AIH is challenging mainly because of its heterogeneous clinical, serological and pathological features. Although portal lymphoplasmacytosis and interface hepatitis are the most typical histological features of AIH, many other histological features can be observed in AIH, including emperipolesis, hepatocyte rosettes, and Kupffer cell hyaline globules. Recent studies have questioned emperipolesis and hepatocyte rosette formation as typical features of AIH, and atypical clinical and histological presentations have also been recognized. This led an international working group to propose the modified AIH diagnostic criteria. However, it is well recognized that there are no pathognomonic characteristics that can be used to diagnose AIH and careful clinicopathological correlation is required to arrive at the correct diagnosis. The aim of this review is to summarize the histological features of AIH, its varied histopathologic spectrum, recent updates and major differential diagnoses in routine clinical practice.

Myeloid-derived suppressor cells ameliorate liver mitochondrial damage to protect against autoimmune hepatitis by releasing small extracellular vesicles

BACKGROUND

Autoimmune hepatitis (AIH) is an inflammatory liver disease that is associated with impaired self-tolerance. Myeloid-derived supprfessor cells (MDSCs) have been considered to exert counterregulatory effects on AIH. However, the specific mechanism underlying these effects is unclear. Herein, we investigated the efficacy and safety of MDSCs in protecting against AIH and explored the underlying mechanism.

METHODS

Circulating and liver MDSC expression levels in 71 AIH patients and 47 healthy control (HC) individuals were detected by flow cytometry and immunohistochemistry. The adoptive transfer of induced bone marrow-derived MDSCs (BM MDSCs) to AIH mice was used to explore the function of MDSCs. Hepatic injury and mitochondrial damage were evaluated by transaminase levels, histopathology, immunohistochemistry, transmission electron microscopy and western blotting. MDSCs were pretreated with the small extracellular vesicle (sEV) generation inhibitor GW4869 to explore the mechanism. Importantly, sEVs derived from MDSCs and MDSCs-GW4869 were injected into model mice to monitor mitochondrial function and biogenesis.

RESULTS

Circulating and liver MDSCs were expanded in AIH patients and mouse model. Furthermore, the follow-up data of AIH patients showed that immunosuppressive therapy further promoted the expansion of MDSCs. More importantly, the adoptive transfer of BM MDSCs to AIH mice effectively ameliorated liver injury and regulated the imbalance of the immune microenvironment. Additionally, BM MDSCs reduced liver mitochondrial damage and improved mitochondrial biogenesis. Mechanistically, sEVs derived from BM MDSCs showed the same biological effects as cells, and blocking sEV production weakened the function of BM MDSCs. Finally, multiple long-term administrations of BM MDSCs were proven to be safe in general.

CONCLUSION

In conclusion, MDSCs ameliorate liver mitochondrial damage to protect against autoimmune hepatitis by releasing small extracellular vesicles.

The progression of chronicity and autoimmune hepatitis in recurrent drug-induced liver injury

BACKGROUND AND AIMS

Recurrent drug-induced liver injury (DILI) is not well documented. We retrospectively analysed the characteristics of patients who had a history of two separate DILI episodes due to different drugs.

METHODS

We collected data from 57 patients with recurrent DILI from 9582 confirmed DILI cases. Demographic, laboratory, and clinical data from both episodes were collected and analysed to determine the relationship between recurrent DILI, chronic DILI, and autoimmune hepatitis (AIH).

RESULTS

The incidence rate of recurrent DILI in our cohort was 0.59%. Most of the 57 patients with recurrent DILI were female (73.68%). The latency period of the initial episode was 30 days, whereas that of the second episode was 13 days (P = 0.003). The pattern of liver injury was not significantly different between episodes (P = 0.52). Laboratory indicators, such as alanine aminotransferase, aspartate transaminase, alkaline phosphatase, and total bilirubin, were significantly lower in the second episode than in the initial episode (P < 0.05). The incidence of chronic DILI was 43.86% during the initial episode and increased to 63.16% during the second episode. After the initial episode, 15 patients developed AIH during the second episode.

CONCLUSIONS

The latency period of recurrent DILI was gradually shortened. The clinical indices of liver injury tended to be less elevated during the second episode. Female post-menopausal patients with abnormal serum immunoglobulin G levels may be predisposed to AIH. The second DILI episode was more likely to have features of AIH.

Role of triglycerides as a predictor of autoimmune hepatitis with cirrhosis

Background

Metabolism-related indicators have been suggested as possible prognostic indicators of liver disease in recent relevant studies, but their value in predicting autoimmune hepatitis (AIH) cirrhosis is unclear. This study evaluated the role of lipid levels in determining the prognosis of AIH-related cirrhosis.

Methods

We retrospectively included 345 patients with AIH who were initially diagnosed at Beijing Ditan Hospital from 2010-2019, and ultimately screened 196 patients who met the criteria. A logistic regression analysis was performed to screen factors associated with cirrhosis. Kaplan–Meier (KM) curves were constructed to analyze the effects of different triglyceride (TG) levels on the survival of patients with cirrhosis. A restricted cubic spline fitted Cox regression model was used to analyze the nonlinear relationship between serum TG levels and patient prognosis.

Results

Patients with AIH cirrhosis have lower TG levels than those without cirrhosis. Lower serum TG levels correlated with the severity of cirrhosis. The survival analysis showed that TG levels were associated with the overall survival of patients with AIH, as a lower 5-year survival rate (log-rank P<0.05) was observed for patients in the TG≤0.95 mmol/L group (hazard ratio (HR)=3.79, 95% CI: 1.528-9.423). In addition, lower TG levels were associated with a higher incidence of death in patients with AIH cirrhosis. The risk of death gradually increased for the interval of TG levels of 0.5-0.8 mmol/L (P for nonlinearity<0.001), and the hazard ratio per standard deviation increase in the TG level was 0.97 (95% CI: 0.94-0.99). The plot showed a U-shaped relationship between TG levels and the survival of patients with decompensated cirrhosis. The risk ratio progressively decreased with lower TG levels (P for nonlinearity=0.002). Below 0.6 mmol/L, the probability of TG risk per standard deviation prediction was 1.49 (95% CI: 1.00-2.24).

Conclusion

Serum TG levels are closely related to the disease severity and overall survival of patients with AIH cirrhosis and may be used as a new indicator of advanced liver disease and long-term prognosis.

Drug-induced liver injury associated with dacomitinib: A case report

Dacomitinib, the second-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been used as a first-line treatment in non-small cell lung cancer (NSCLC) patients harboring EGFR mutation. In this case, we report a patient with drug-induced liver injury (DILI) associated with the use of dacomitinib. A 59-year-old man with stage IV NSCLC was prescribed with dacomitinib; 37 days after dacomitinib administration, he was admitted to our hospital because of jaundice. Laboratory examinations revealed elevated serum levels of liver enzymes and bilirubin. Following the immediate discontinuation of dacomitinib, liver enzymes decreased but bilirubin continued to rise. Total bilirubin reached the peak (18-fold) on day 26 after dacomitinib termination and normalized on day 146 after dacomitinib discontinuation. A "probable" cause of DILI by dacomitinib was determined based on the Roussel Uclaf Causality Assessment Method. The severity of DILI was assessed as acute liver failure. To our knowledge, this is the first case of DILI caused by dacomitinib monotherapy in a real-world setting. Clinicians should pay particular attention to the possibility of DILI during dacomitinib treatment.

Metabolic heterogeneity caused by HLA-DRB1*04:05 and protective effect of inosine on autoimmune hepatitis

Autoimmune hepatitis (AIH) is an autoimmune disease caused by disruption of liver immune homeostasis. Genetic studies have revealed the predisposition of AIH with the human leukocyte antigen (HLA) region. Recently, metabolomics integrated with genomics has identified many genetic loci of biomedical interest. However, there is no related report in AIH. In the present study, we found that HLA-DRB1*04:05 was linked to the clinical features and prognosis of AIH in Chinese patients. Furthermore, our patients were divided into DRB1*04:05 positive and DRB1*04:05 negative groups and the metabolic profiling was done by HPLC/MS. We chose inosine, one of the highly altered metabolites, to explore the effect on an acute severe hepatitis murine model. The results showed that inosine treatment attenuated hepatocyte apoptosis, enhanced antioxidant ability and inhibited the activation and glycolysis of CD4⁺ T cell. We propose that inosine participates in the regulation of AIH through its protective effect on hepatocytes and inhibition of overactivated immune cells, which might provide a potential novel approach in treating acute form of AIH.

Epidemiology and surveillance of autoimmune hepatitis in Asia

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease that mainly injures the hepatocytes. The autoimmune disease might be involved in its aetiology, but this remains to be confirmed. Recently epidemiological studies of AIH in Asia have been broadly conducted, revealing characteristics and management of AIH patients in Asia. In East Asia, most AIH patients are type 1, and type 2 AIH is very rare. However, type 2 AIH in South Asia is as frequent as in Europe and the USA. HLA-DR4 is associated with the characteristics of type 1 AIH in East Asia, whereas HLA-DR3 occurs in AIH patients from South Asia. AIH prevalence worldwide is increasing, and several studies have reported a prevalence of 19.44, 22.80 and 12.99 per 100 000 people in Europe, the USA and Asia respectively. A meta-analysis of studies on AIH showed similar annual incidence rates for all regions, with 1.31, 1.37 and 1.00 per 100 000 people in Asia, Europe and the USA respectively. The increase in the rates could be attributable to the increased awareness of disease concepts and diagnosis. In South Asia, most cases were diagnosed as AIH only after having progressed to cirrhosis, which may cause a higher mortality rate in South Asia than in East Asia. Therefore, the early diagnosis and treatment of AIH patients can improve the current situation in Asia.

Coronavirus disease 2019 (COVID-19) in autoimmune hepatitis

Severe acute respiratory syndrome coronavirus 2 is a highly transmissible and pathogenic virus that leads to coronavirus disease 2019 (COVID-19). The preexisting liver diseases alter the course of COVID-19. Therefore, specific management strategies must be considered in individuals with chronic liver diseases (CLDs) and COVID-19. Autoimmune hepatitis (AIH) is a rare immune-mediated liver disease. Patients with AIH require life-long treatment with immunosuppressive drugs that may increase the risk of poor COVID-19 outcomes. The stage of underlying liver disease is another factor that can affect the clinical outcomes of COVID-19 in patients with AIH. In this review, we aim to provide relevant issues that will be helpful to clinicians in understanding and improving the clinical care for patients with AIH during the pandemic.

Effects of immunosuppressive drugs on COVID-19 severity in patients with autoimmune hepatitis

BACKGROUND

We investigated associations between baseline use of immunosuppressive drugs and severity of Coronavirus Disease 2019 (COVID-19) in autoimmune hepatitis (AIH).

PATIENTS AND METHODS

Data of AIH patients with laboratory confirmed COVID-19 were retrospectively collected from 15 countries. The outcomes of AIH patients who were on immunosuppression at the time of COVID-19 were compared to patients who were not on AIH medication. The clinical courses of COVID-19 were classified as (i)-no hospitalization, (ii)-hospitalization without oxygen supplementation, (iii)-hospitalization with oxygen supplementation by nasal cannula or mask, (iv)-intensive care unit (ICU) admission with non-invasive mechanical ventilation, (v)-ICU admission with invasive mechanical ventilation or (vi)-death and analysed using ordinal logistic regression.

RESULTS

We included 254 AIH patients (79.5%, female) with a median age of 50 (range, 17-85) years. At the onset of COVID-19, 234 patients (92.1%) were on treatment with glucocorticoids (n = 156), thiopurines (n = 151), mycophenolate mofetil (n = 22) or tacrolimus (n = 16), alone or in combinations. Overall, 94 (37%) patients were hospitalized and 18 (7.1%) patients died. Use of systemic glucocorticoids (adjusted odds ratio [aOR] 4.73, 95% CI 1.12-25.89) and thiopurines (aOR 4.78, 95% CI 1.33-23.50) for AIH was associated with worse COVID-19 severity, after adjusting for age-sex, comorbidities and presence of cirrhosis. Baseline treatment with mycophenolate mofetil (aOR 3.56, 95% CI 0.76-20.56) and tacrolimus (aOR 4.09, 95% CI 0.69-27.00) were also associated with more severe COVID-19 courses in a smaller subset of treated patients.

CONCLUSION

Baseline treatment with systemic glucocorticoids or thiopurines prior to the onset of COVID-19 was significantly associated with COVID-19 severity in patients with AIH.

Presence of Serum Antinuclear Antibodies Does Not Impact Outcomes in HBV-Related Acute-on-Chronic Liver Failure

BACKGROUND

The aim of this study was to provide new insights into the prevalence of positive antinuclear antibody (ANA) in patients with HBV-related acute-on-chronic liver failure (ACLF) and its impact on clinical outcomes.

METHODS

A total of 116 patients with HBV-related ACLF treated at three clinical centers were retrospectively recruited. Serum concentrations of ANA were detected using the enzyme-linked immunosorbent assay kit. Multiple nuclear dots, rim-like, and centromere patterns of ANA were detected using indirect immunofluorescence assay on HEp-2 cells.

RESULTS

Among the 116 patients with HBV-related ACLF, 17 (14.66%) were ANA positive. Most patients in both ANA positive and negative groups were males (88.2% and 83.8%). Patients with negative ANA had a higher international normalized ratio, model for end-stage liver disease (MELD), and MELD-sodium scores than those with positive ANA (all P < 0.05). Multiple nuclear dot pattern was detected in half of the patients (8/17, 47.06%), rim-like/membranous pattern was found in six patients, and centromere pattern was detected in the last three patients. For patients with ANA (+), IgM was lower, and it was positively correlated with IgG. For patients with ANA (-), C3 was positively correlated with C4, and both C3 and C4 were negatively correlated with INR and MELD (all P < 0.05). In addition, TBIL, INR, WBC, and PLT, but not ANA, resulted as independent risk factors associated with 90-day mortality.

CONCLUSION

Positive ANA is frequent in HBV-related ACLF, and it does not seem to be associated with poor outcomes, but the pathogenesis of ACLF may be different between ANA (+) and ANA (-) groups.

First Results From a Propensity Matching Trial of Mycophenolate Mofetil vs. Azathioprine in Treatment-Naive AIH Patients

Background/Aims

As previous real-world studies and meta-analyses have shown that mycophenolate mofetil (MMF) might have better efficacy than azathioprine (AZA) in autoimmune hepatitis (AIH), we conducted a propensity matching study to assess the efficacy and safety of MMF vs. AZA.

Methods

All 126 consecutive treatment-naive adult AIH patients, diagnosed and followed in our department since 2016, were included. Patients received prednisolone 0.5-1 mg/kg/day plus either AZA 1-2 mg/kg/day or 1.5-2 g/day MMF. The tapering of prednisolone was identical between groups.

Results

After propensity matching score and adjustment for known factors affecting response to treatment and outcome, 64 patients were included in the study (MMF = 32 and AZA = 32). Rates of non-response, complete biochemical response (CBR) at 6 and 12 months, and prednisolone withdrawal (6 months, 12 months, and end of follow-up) were identical between groups. However, MMF treatment was significantly associated with CBR at the end of follow-up [odds ratio (OR) 11.259; 95% CI: 1.3-97.4, p = 0.028]. AZA patients were more prone to stop treatment due to AZA intolerance/insufficient response (p = 0.0001). At the end of follow-up, the overall efficacy of each schedule was also significantly higher in the MMF group compared to the AZA group (p = 0.0001).

Conclusion

We showed for the first time in a propensity matching study that MMF can be used as first-line therapy in AIH as attested by the significantly higher CBR at end of follow-up compared to AZA. Whether this better efficacy is also associated with higher histological remission rates and sustained CBR off immunosuppression needs further evaluation.

Impact of genetic and environmental factors on autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic non-resolving liver disease characterized by diffuse hypergammaglobulinemia, the presence of autoantibodies and characteristic histological findings. The disease can have catastrophic outcome with the development of end-stage liver disease if misdiagnosed/undiagnosed and left untreated. AIH pathogenesis remains obscure and the main hypothesis supports its development in genetically predisposed individuals after being exposed to certain environmental triggers. Genetic predisposition is linked to the presence of certain HLA alleles, mainly HLA-DR3 and HLA-DR4. However, a wide number of non-HLA epitopes have also been associated with the disease although data vary significantly among different ethnic groups. Therefore, it is likely that epigenetic alterations may also play a crucial role in disease's pathogenesis, although not yet extensively studied. The aim of this review was to summarize the genetic and environmental factors that have been associated with AIH, but also to open new insights towards the role of epigenetic modifications in the etiology of the disease.