Antismooth muscle and antiactin antibodies are indirect markers of histological and biochemical activity of autoimmune hepatitis

Natural history and long-term management of autoimmune hepatitis

INTRODUCTION

Autoimmune hepatitis (AIH) is a relatively infrequent and complex liver disease characterized by acute or chronic inflammation, interface hepatitis in histology examination, elevation of immunoglobulin G (IgG), production of autoantibodies, and is often responsive to immunosuppression. The incidence of AIH has been increasing worldwide, affecting people of all ages and sexes. AIH represents a diagnostic challenge because of its heterogeneous presentation and the lack of pathognomonic findings. Even when treated, AIH can remain a progressive disease. In this review, we present recent data on the natural history of AIH and the developing evidence on the management of patients with AIH.

AREAS COVERED

This review outlines the clinical presentation, risk factors linked to poorer clinical outcomes, the diagnostic algorithm, and the current management strategies for individuals living with AIH.

EXPERT OPINION

AIH remains a clinical challenge, and new tools for better diagnosis and stratification of risk are needed. In addition, better treatments are needed as a complete response is achieved in less than 60% of cases, and intolerance to first-line treatment is frequent. The use of biological treatment in AIH seems to improve the response rate and minimize the risk of side effects of current medication in this increasingly prevalent disease.

Autoimmune hepatitis presenting as severe anemia

Autoimmune hepatitis (AIH) is relatively rare in children. Herein, our case demonstrates a unique presentation of AIH in a previously healthy 18-year-old female presenting with a mild cough, fatigue, and severe anemia (hemoglobin 2.9 g/dL). Initial evaluation revealed jaundice and scleral icterus, prompting transfer of care and further testing, which demonstrated severe microcytic anemia, pancytopenia, elevated liver enzymes, direct hyperbilirubinemia, and marked splenomegaly. Concern for autoimmune hemolytic anemia resulted in a delayed diagnosis. The combination of triple antibody positivity (anti-nuclear antibodies, anti-actin, and anti-liver-kidney microsomal-1) and liver histology findings confirmed the diagnosis of AIH. Intravenous methylprednisolone was initiated to induce remission. Due to pancytopenia and persistently elevated international normalized ratio, tacrolimus was chosen as the maintenance immunosuppression instead of azathioprine. This case highlights several significant considerations for clinicians, including the importance of a timely clinicopathologic diagnosis, the severe anemia presentation secondary to hypersplenism, and the rare finding of triple autoantibody-positive AIH.

Clinical, biochemical and histological features related to treatment response and prognosis in autoimmune hepatitis

INTRODUCTION AND OBJECTIVES

Autoimmune hepatitis (AIH) is a rare disease with a complex and not fully understood pathogenesis. Prognostic factors that might influence treatment response, relapse rates, and transplant-free survival are not well established. This study investigates clinical and biochemical markers associated with response to immunosuppression in patients with AIH.

MATERIALS AND METHODS

This retrospective cohort study included 102 patients with AIH treated with immunosuppressants and followed at the Federal University of Minas Gerais, Brazil, from 1990 to 2018. Pretreatment data such as clinical profiles, laboratory, and histological exams were analyzed regarding biochemical response at one year, histological remission, relapse, and death/transplantation rates.

RESULTS

Cirrhosis was present in 59 % of cases at diagnosis. One-year biochemical remission was observed in 55.7 % of the patients and was found to be a protective factor for liver transplant. Overall survival was 89 %. Patients with ascites at disease onset showed a higher aspartate aminotransferase (AST)/ alanine aminotransferase (ALT) ratio and elevated Model of end-stage liver disease (MELD) score. The presence of ascites was significantly associated with a 20-fold increase in mortality rate.

CONCLUSIONS

AIH has a severe clinical phenotype in Brazilians, with high rates of cirrhosis and low remission rates. Early diagnosis and treatment are essential for achieving remission and reducing complications. The presence of ascites is significantly associated with mortality, emphasizing the importance of monitoring and prompt intervention. This study also stresses the need for further research on AIH in Latin America.

Primary Biliary Cholangitis (PBC)-Autoimmune Hepatitis (AIH) Variant Syndrome: Clinical Features, Response to Therapy and Long-Term Outcome

INTRODUCTION

Standardization of diagnostic criteria of autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) variant syndrome (AIH-PBC VS) has not been achieved so far and evidence-based recommendations for monitoring and treatment of the disease are still lacking. Our study aimed to assess the prevalence, biochemical, and serological features, as well as the clinical course, of VS.

METHODS

We performed a retrospective study including all patients with VS between 1999 and 2020 in four German centers. Data on demographic parameters, biochemical and serological tests, treatment, and outcome were collected.

RESULTS

Of 90 patients (3.1%) meeting Paris criteria for VS diagnosis, 65.6% showed AIH and PBC histological features, while biochemical Paris criteria were observed comparatively rarely. Further antibodies, which were not part of the diagnostic criteria of VS, were found in a subgroup of patients with available data (ACA: 30.0%; anti-CENP-A: 25.0%; anti-CENP-B: 33.3%; anti-SP100: 21.4%). Biochemical response was more frequently observed in patients treated with a combined therapy of ursodeoxycholic acid (UDCA) and immunosuppression (IS). Liver cirrhosis was detected in 31 patients (34.4%) and 25 patients (27.8%) developed clinical manifestations of portal hypertension.

CONCLUSIONS

Biochemical Paris criteria of VS were rarely detected, thus implying that these cut-off values should be redefined. Regarding pharmacological treatment, combined therapy of UDCA and IS appeared to be more effective than monotherapy with UDCA.

The protective effects of sesamol and/or the probiotic, Lactobacillus rhamnosus, against aluminum chloride-induced neurotoxicity and hepatotoxicity in rats: Modulation of Wnt/β-catenin/GSK-3β, JAK-2/STAT-3, PPAR-γ, inflammatory, and apoptotic pathways

Introduction: Aluminium (Al) is accumulated in the brain causing neurotoxicity and neurodegenerative disease like Alzheimer's disease (AD), multiple sclerosis, autism and epilepsy. Hence, attenuation of Al-induced neurotoxicity has become a "hot topic" in looking for an intervention that slow down the progression of neurodegenerative diseases. Objective: Our study aims to introduce a new strategy for hampering aluminum chloride (AlCl3)-induced neurotoxicity using a combination of sesamol with the probiotic bacteria; Lactobacillus rhamnosus (L. rhamnosus) and also to test their possible ameliorative effects on AlCl3-induced hepatotoxicity. Methods: Sprague-Dawley male rats were randomly divided into five groups (n = 10/group) which are control, AlCl3, AlCl3 + Sesamol, AlCl3 + L. rhamnosus and AlCl3 + Sesamol + L. rhamnosus. We surveilled the behavioral, biochemical, and histopathological alterations centrally in the brain and peripherally in liver. Results: This work revealed that the combined therapy of sesamol and L. rhamnosus produced marked reduction in brain amyloid-β, p-tau, GSK-3β, inflammatory and apoptotic biomarkers, along with marked elevation in brain free β-catenin and Wnt3a, compared to AlCl3-intoxicated rats. Also, the combined therapy exerted pronounced reduction in hepatic expressions of JAK-2/STAT-3, inflammatory (TNF-α, IL-6, NF-κB), fibrotic (MMP-2, TIMP-1, α-SMA) and apoptotic markers, (caspase-3), together with marked elevation in hepatic PPAR-γ expression, compared to AlCl3 -intoxicated rats. Behavioral and histopathological assessments substantiated the efficiency of this combined regimen in halting the effect of neurotoxicity. Discussion: Probiotics can be used as an add-on therapy with sesamol ameliorate AlCl3 -mediated neurotoxicity and hepatotoxicity.

Noninvasive biomarkers for the diagnosis and management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a rare disease of unclear etiology characterized by loss of self-tolerance that can lead to liver injury, cirrhosis, and acute liver failure. First-line treatment consists of systemic corticosteroids, or budesonide, and azathioprine, to which most patients are initially responsive, although predictors of response are lacking. Relapses are very common, correlate with histological activity despite normal serum transaminases, and increase hepatic fibrosis. Furthermore, current regimens lead to adverse effects and reduced quality of life, whereas medication titration is imprecise. Biomarkers that can predict the clinical course of disease, identify patients at elevated risk for relapse, and improve monitoring and medication dosing beyond current practice would have high clinical value. Herein, we review novel candidate biomarkers in adult and pediatric AIH based on prespecified criteria, including gene expression profiles, proteins, metabolites, and immune cell phenotypes in different stages of AIH. We also discuss biomarkers relevant to AIH from other immune diseases. We conclude with proposed future directions in which biomarker implementation into clinical practice could lead to advances in personalized therapeutic management of AIH.

Autoimmune Hepatitis: Serum Autoantibodies in Clinical Practice

Circulating autoantibodies are a key diagnostic tool in autoimmune hepatitis (AIH), being positive in 95% of the cases if tested according to dedicated guidelines issued by the International Autoimmune Hepatitis Group. They also allow the distinction between type 1 AIH, characterized by positive anti-nuclear and/or anti-smooth muscle antibody, and type 2 AIH, characterized by positive anti-liver kidney microsomal type 1 and/or anti-liver cytosol type 1 antibody. Anti-soluble liver antigen is the only AIH-specific autoantibody, and is found in 20-30% of both type 1 and type 2 AIH. Anti-neutrophil cytoplasmic antibody is frequently positive in type 1 AIH, being associated also with inflammatory bowel disease and with primary/autoimmune sclerosing cholangitis. The reference method for autoantibody testing remains indirect immunofluorescence on triple tissue (rodent liver, kidney and stomach), allowing both the detection of the majority of liver-relevant reactivities, including those autoantibodies whose molecular target antigens are unknown. Of note, the current knowledge of the clinical significance of autoantibodies relies on studies based on this technique. However, immunofluorescence requires trained laboratory personnel, is observer-dependent, and lacks standardization, leading to ongoing attempts at replacing this method with automated assays, the sensitivity, and specificity of which, however, require further studies before they can be used as a reliable alternative to immunofluorescence; currently, they may be used as complementary to immunofluorescence.

New agents for immunosuppression

The human abdomen harbors organs that the host's immune system can attack easily. This immunological storm front leads to diseases like Crohn's Disease, Ulcerative Colitis or Autoimmune Hepatitis. Serious symptoms like pain, diarrhea, fatigue, or malnutrition accompany these diseases. Moreover, many patients have an increased risk for developing special kind of malignancies and some autoimmune disease can show a high mortality. The key to treat them consists of a deep understanding of their pathophysiology. In vitro and especially in vivo basic research laid the foundation for our increasing knowledge about it during the past years. This enabled the development of new therapeutic approaches that interact directly with cytokines or immune cells instead of building the treatment on a total immunosuppression. Different kind of antibodies, kinase inhibitors, and regulatory T cells build the base for these approaches. This review shows new therapeutical approaches in gastrointestinal autoimmune diseases in context to their pathophysiological basis.

Sustained Remission After Treatment Withdrawal in Autoimmune Hepatitis: A Multicenter Retrospective Study

BACKGROUND

In patients with autoimmune hepatitis (AIH), relapse rates between 25 and 100% after treatment withdrawal have been reported. The optimal strategy for immunosuppressive treatment withdrawal is controversial.

AIM

To identify the predictive factors of histological remission and to assess the relapse rate after treatment withdrawal in AIH patients with prolonged biochemical response.

METHODS

Patients with AIH and sustained biochemical remission on first-line treatment were retrospectively included. Histological response was defined as complete regression of interface hepatitis and lobular necrosis and no or minimal portal inflammation and relapse as any elevation of serum aminotransferase or gammaglobulin/IgG levels.

RESULTS

Sixty-two patients were included. Forty-seven had a biopsy after a median biochemical response of 49.7 months. Twenty-five of them were histological responders. Independent predictors of histological remission were older age (OR = 1.1; CI 95%: 1.0; 1.2), mild-to-moderate fibrosis at diagnosis (OR = 8; CI: 1.4; 47.6) and aspartate aminotransferases < 0.6 × ULN (OR = 7.1; CI: 1.3; 36.7). Thirty-nine patients stopped therapy after a median biochemical response of 48.6 months. Twenty-four of them had a biopsy before treatment withdrawal: 21 were histological responders. The cumulative rate of relapse was 25% at 64 months.

CONCLUSIONS

This study indicates that older age, mild-to-moderate fibrosis at diagnosis and serum aspartate aminotransferases in the lower range of normal are independent predictors of histological response in AIH with prolonged biochemical response. The relapse rate after treatment withdrawal may be limited to 25% at 64 months when patients are selected on the basis of prolonged biochemical remission and, when available, histological response.

Genetic aspects of adult and pediatric autoimmune hepatitis: A concise review

Autoimmune Hepatitis (AIH) is a heterogenous, mostly chronic liver disease that affects people of all age groups, women more often than men. The aim of therapy is to prevent cirrhosis, as it mainly accounts for liver-related mortality in patients with AIH. Rates of remission are high in patients with AIH, but life-long immunosuppressive therapy is required. AIH is hypothesized to originate from immunologic reactivity targeted against mostly unknown self-antigens, potentially triggered by viral infections among other factors. While AIH does not follow a Mendelian inheritance pattern, part of the risk of developing AIH or worse disease course, is attributed to specific genetic risk factors. Major associations for the risk of development of AIH were found for HLA-DRB1*03:01 and HLA-DRB1*04:01 in adult AIH in the only genome-wide association study on AIH. However, other potential risk loci in SH2B3, CARD10 and KIR genes were described. This review covers the current knowledge on genetic risk factors in adult and pediatric AIH.

Antigen presentation, autoantibody production, and therapeutic targets in autoimmune liver disease

The liver is an important immunological organ that controls systemic tolerance. The liver harbors professional and unconventional antigen-presenting cells that are crucial for tolerance induction and maintenance. Orchestrating the immune response in homeostasis depends on a healthy and well-toned immunological liver microenvironment, which is maintained by the crosstalk of liver-resident antigen-presenting cells and intrahepatic and liver-infiltrating leukocytes. In response to pathogens or autoantigens, tolerance is disrupted by unknown mechanisms. Intrahepatic parenchymal and nonparenchymal cells exhibit unique antigen-presenting properties. The presentation of microbial and endogenous lipid-, metabolite- and peptide-derived antigens from the gut via conventional and nonconventional mechanisms can educate intrahepatic immune cells and elicit effector responses or tolerance. Perturbation of this balance results in autoimmune liver diseases, such as autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. Although the exact etiologies of these autoimmune liver diseases are unknown, it is thought that the disruption of tolerance towards self-antigens and microbial metabolites and lipids, as well as alterations in bile acid composition, may result in changes in effector cell activation and polarization and may reduce or impair protective anti-inflammatory regulatory T and B cell responses. Additionally, the canonical and noncanonical transmission of antigens and antigen:MHC complexes via trogocytosis or extracellular vesicles between different (non) immune cells in the liver may play a role in the induction of hepatic inflammation and tolerance. Here, we summarize emerging aspects of antigen presentation, autoantibody production, and the application of novel therapeutic approaches in the characterization and treatment of autoimmune liver diseases.

Regulatory T Cells in Autoimmune Hepatitis: Unveiling Their Roles in Mouse Models and Patients

Autoimmune hepatitis (AIH) is a severe and chronic liver disease, and its incidence has increased worldwide in recent years. Research into the pathogenesis of AIH remains limited largely owing to the lack of suitable mouse models. The concanavalin A (ConA) mouse model is a typical and well-established model used to investigate T cell-dependent liver injury. However, ConA-induced hepatitis is acute and usually disappears after 48 h; thus, it does not mimic the pathogenesis of AIH in the human body. Several studies have explored various AIH mouse models, but as yet there is no widely accepted and valid mouse model for AIH. Immunosuppression is the standard clinical therapy for AIH, but patient side effects and recurrence limit its use. Regulatory T cells (Tregs) play critical roles in the maintenance of immune homeostasis and in the prevention of autoimmune diseases, which may provide a potential therapeutic target for AIH therapy. However, the role of Tregs in AIH has not yet been clarified, partly because of difficulties in diagnosing AIH and in collecting patient samples. In this review, we discuss the studies related to Treg in various AIH mouse models and patients with AIH and provide some novel insights for this research area.

Particularities of Autoimmune Hepatitis in Latin America

Watch a video presentation of this article.

EVALUATION OF PATIENTS WITH AUTOIMMUNE HEPATITIS IN A SPECIALIZED OUTPATIENT CLINIC IN SOUTHERN BRAZIL

BACKGROUND

Autoimmune hepatitis (AIH) is a chronic liver disease, characterized by necroinflammation and autoimmune etiology. Studies evaluating the characteristics of patients with AIH are scarce in Brazil.

OBJECTIVE

Our objective was to evaluate the profile of patients with AIH in a specialized center in Southern Brazil and to verify factors related to treatment response.

METHODS

this was a retrospective cohort study, which analyzed demographic, epidemiological, clinical, laboratory, and histologic data. Patients with AIH diagnosed according to the criteria of the International Autoimmune Hepatitis Group (IAIHG) were included. In liver biopsies, the degree of fibrosis, histological activity, presence of hepatocyte rosettes, plasma cell infiltrates, and confluent necrosis were evaluated. In the statistical analysis, the significance level was 5%.

RESULTS

Forty adults patients diagnosed with AIH were included. The evaluated population predominantly consisted of women (75.0%) and the average age at diagnosis was 44.2 years. The association with extrahepatic autoimmune diseases occurred in 20.0% of cases. Clinically, 35.0% of patients presented with acute onset hepatitis, 37.5% with cirrhosis, and 27.5% with other forms of presentation. The most common clinical manifestation was jaundice (47.5%). Thirty-five patients were treated, and of these, 97.1% used prednisone combined with azathioprine. The average treatment time was 2.7 years. Response to treatment was complete or partial in 30 (85.7%) and absent in 5 (14.3%) patients. There was no statistically significant difference when evaluating response to treatment in relation to forms of presentation, histological findings, and the presence of autoantibodies. Regarding fibrosis, regression was observed in 18.75% of the cases.

CONCLUSION

Most patients with AIH were young at presentation and of female sex. The association with extrahepatic autoimmune diseases and cirrhosis at presentation was seen in a considerable proportion of patients. Treatment was effective, but there were no clinical, histological or serological parameters capable of predicting treatment response.

[Autoimmune liver diseases]

Autoimmune liver diseases comprise a spectrum of progredient idiopathic inflammatory diseases. Typical histological features of autoimmune hepatitis (AIH) include the pattern of chronic hepatitis with predominant plasma cell-rich interface activity, rosetting of hepatocytes, and emperipolesis. Florid bile duct lesions are the key feature of primary biliary cholangitis (PBC); onion-like periductal fibrosis characterizes the primary sclerosing cholangitis (PSC). Variants of AIH, or overlap syndromes, show intersecting histomorphologic findings with PBC or PSC. The diagnosis of the different autoimmune inflammatory liver diseases is based on clinical presentation, a hepatitic or cholestatic pattern of liver enzymes, immuno-serological findings, image analysis in PSC, and liver biopsy as a facultative or obligatory adjunct. Liver biopsy plays a major role in the diagnosis of AIH, small-duct PSC, AMA-negative PBC, IgG4-related diseases, overlap syndrome, and in the recognition of concurrent liver diseases, especially drug-induced liver diseases. Herewith pathologists can help clinicians find adequate therapy for different autoimmune inflammatory liver diseases.

Permanent immunosuppression in SLA/LP-positive autoimmune hepatitis is required although overall response and survival are similar

BACKGROUND AND AIMS

Antibodies against soluble liver antigen/liver pancreas (anti-SLA/LP) are highly specific for autoimmune hepatitis (AIH) and have been linked with a more severe clinical course of the disease, frequent relapses after treatment withdrawal and worse outcome. To address definitely the clinical significance of anti-SLA/LP, we investigated a large number of anti-SLA/LP-positive and -negative patients followed in three referral centres.

METHODS

Prospectively collected data from 89 anti-SLA/LP-positive AIH patients (29 from Hamburg-Germany, 20 from Bologna-Italy and 40 from Larissa-Greece) were analysed retrospectively. Age- and sex-matched anti-SLA/LP-negative patients served as disease controls (n = 230; 1:2.5 ratio).

RESULTS

In respect to baseline characteristics, anti-SLA/LP-positive patients were more frequently asymptomatic compared to anti-SLA/LP-negative (P < .05). However, anti-SLA/LP-positive patients did not differ from anti-SLA/LP-negative in terms of the overall response to treatment, disease progression and survival even though, they were less likely to achieve corticosteroid withdrawal (P < .05), needed longer treatment duration to achieve first complete response (P < .001) and relapsed more frequently after treatment withdrawal compared to anti-SLA/LP-negative patients (P = <.001).

CONCLUSIONS

We showed that anti-SLA/LP antibodies do not characterize a group of AIH patients with distinct features and cannot identify patients with a more severe form of the disease or worse survival. Most importantly, however, anti-SLA/LP-positive patients appear to require lifelong immunosuppression as they are less likely to achieve the cessation of corticosteroids and present higher relapse rates after treatment withdrawal. Therefore, close long-term monitoring should be advised in all anti-SLA/LP-positive patients after withdrawal of immunosuppressive treatment.

Examining pathogenic concepts of autoimmune hepatitis for cues to future investigations and interventions

BACKGROUND

Multiple pathogenic mechanisms have been implicated in autoimmune hepatitis, but they have not fully explained susceptibility, triggering events, and maintenance or escalation of the disease. Furthermore, they have not identified a critical defect that can be targeted. The goals of this review are to examine the diverse pathogenic mechanisms that have been considered in autoimmune hepatitis, indicate investigational opportunities to validate their contribution, and suggest interventions that might evolve to modify their impact. English abstracts were identified in PubMed by multiple search terms. Full length articles were selected for review, and secondary and tertiary bibliographies were developed. Genetic and epigenetic factors can affect susceptibility by influencing the expression of immune regulatory genes. Thymic dysfunction, possibly related to deficient production of programmed cell death protein-1, can allow autoreactive T cells to escape deletion, and alterations in the intestinal microbiome may help overcome immune tolerance and affect gender bias. Environmental factors may trigger the disease or induce epigenetic changes in gene function. Molecular mimicry, epitope spread, bystander activation, neo-antigen production, lymphocytic polyspecificity, and disturbances in immune inhibitory mechanisms may maintain or escalate the disease. Interventions that modify epigenetic effects on gene expression, alter intestinal dysbiosis, eliminate deleterious environmental factors, and target critical pathogenic mechanisms are therapeutic possibilities that might reduce risk, individualize management, and improve outcome. In conclusion, diverse pathogenic mechanisms have been implicated in autoimmune hepatitis, and they may identify a critical factor or sequence that can be validated and used to direct future management and preventive strategies.

Autoimmune Hepatitis-Immunologically Triggered Liver Pathogenesis-Diagnostic and Therapeutic Strategies

Autoimmune hepatitis (AIH) is a severe liver disease that arises in genetically predisposed male and female individuals worldwide. Diagnosis of AIH is made clinically applying diagnostic scores; however, the heterotopic disease phenotype often makes a rapid determination of disease challenging. AIH responds favorably to steroids and pharmacologic immunosuppression, and liver transplantation is only necessary in cases with acute liver failure or end-stage liver cirrhosis. Recurrence or development of de novo AIH after transplantation is possible, and treatment is similar to standard AIH therapy. Current experimental investigations of T cell-mediated autoimmune pathways and analysis of changes within the intestinal microbiome might advance our knowledge on the pathogenesis of AIH and trigger a spark of hope for novel therapeutic strategies.

UPDATE OF THE BRAZILIAN SOCIETY OF HEPATOLOGY RECOMMENDATIONS FOR DIAGNOSIS AND MANAGEMENT OF AUTOIMMUNE DISEASES OF THE LIVER

New data concerning the management of autoimmune liver diseases have emerged since the last single-topic meeting sponsored by the Brazilian Society of Hepatology to draw recommendations about the diagnosis and treatment of autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), overlap syndromes of AIH, PBC and PSC and specific complications and topics concerning AIH and cholestatic liver diseases. This manuscript updates those previous recommendations according to the best evidence available in the literature up to now. The same panel of experts that took part in the first consensus document reviewed all recommendations, which were subsequently scrutinized by all members of the Brazilian Society of Hepatology using a web-based approach. The new recommendations are presented herein.

Grand round: Autoimmune hepatitis

Autoimmune hepatitis is a corticosteroid-responsive liver disease arising consequent to immunogenetic and environmental risk factors. The clinical course reflects relapsing and remitting, hepatocyte targeted immunologic damage, which is countered by reparative responses to cell injury. Appropriate and timely immunosuppressive therapy drives the disease into remission, albeit with inevitable side effects. Many challenges faced in the clinic reflect practice that must capture a heterogeneous disease presentation, course, and treatment response, as well as treatment tolerability. In this Grand Round we appraise the evidence supporting current treatment approaches, address the impact of autoimmune liver disease 'crossover or overlap' presentations, explore important clinical correlates to immune-serological classifiers, and discuss the factors influencing choice of alternative therapy in difficult-to-treat situations.

Decreased health-related quality of life in children and adolescents with autoimmune hepatitis

OBJECTIVE

The objective of this study was to evaluate the health-related quality of life in children and adolescents with autoimmune hepatitis.

METHODS

A cross-sectional assessment with the Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0) was completed for 80 patients with autoimmune hepatitis and 45 healthy controls. Demographic data, prednisone dose, disease remission state, disease severity, and abdominal pain were also evaluated.

RESULTS

Based on the child self-reports, physical, emotional, school, and total scores were significantly lower in autoimmune hepatitis patients when compared with controls (p<0.05). Based on the parental reports, only the physical and total scores were significantly lower in autoimmune hepatitis patients versus controls (p<0.05). Further analysis in autoimmune hepatitis patients with abdominal pain in the last month revealed significantly lower physical, social, and total median scores (p<0.05). No differences were observed based on disease remission state or disease severity (p>0.05). Autoimmune hepatitis patients who received a prednisone dose below 0.16mg/kg/day at the time of the interview showed significantly higher physical scores than those who received a dose similar to or above 0.16mg/kg/day (87.5 [50-100] vs. 75 [15.63-100], p=0.006).

CONCLUSIONS

Reduced scores in the physical, emotional, and school domains were observed in pediatric autoimmune hepatitis patients compared to control patients. Abdominal pain and corticosteroid dose negatively influenced the health-related quality of life in children and adolescents with autoimmune hepatitis.

Variant syndromes of primary biliary cholangitis

Patients with primary biliary cholangitis (PBC) can show biochemical, serological and/or histological features of autoimmune hepatitis (AIH). The term 'AIH-PBC overlap syndrome' has been used frequently for these cases and implies the coexistence of two separate diseases. However, the boundaries between 'classical' PBC, PBC with features of AIH and 'classical' AIH are difficult to define, and therefore the term 'variant syndrome' should be preferred. A variant syndrome must primarily be assumed in PBC patients showing pronounced hepatitic activity, either expressed by elevated transaminases and raised levels of serum IgG/gammaglobulins or more specifically by liver biopsy showing a modified hepatitis activity index (mHAI) score of >4/18. The presence of AIH-specific autoantibodies also supports the diagnosis of a variant syndrome. The diagnosis must not be missed because individually adapted immunosuppressive treatment, analogous to AIH therapy, appears to have an important beneficial impact on the prognosis and should therefore be offered to these patients.

Emerging therapeutic biomarkers of autoimmune hepatitis and their impact on current and future management

Autoimmune hepatitis lacks a quantifiable biomarker that is close to its pathogenic mechanisms and that accurately reflects inflammatory activity, correlates with treatment response, and ensures inactive disease before treatment withdrawal. Areas covered: Micro-ribonucleic acids, programmed death-1 protein and its ligands, macrophage migration inhibitory factor, soluble CD163, B cell activating factor, and metabolite patterns in blood were considered the leading candidates as therapeutic biomarkers after search of PubMed from August 1981 to August 2017 using the search words 'biomarkers of autoimmune hepatitis'. Expert commentary: Each of the candidate biomarkers is close to the putative pathogenic mechanisms of autoimmune hepatitis, and each has attributes that support its potential role as a surrogate marker of inflammatory activity that can be monitored during treatment. Future studies must demonstrate the superiority of each biomarker to conventional indices of inflammatory activity and validate their correlation with treatment response and outcome. A reliable therapeutic biomarker would facilitate the individualization of current management algorithms, ensure that pathogenic mechanisms were disrupted or eliminated prior to treatment withdrawal, and reduce the frequency of relapse or unnecessary protracted therapy. The biomarker might also prove to be a target of next-generation therapies.

Autoimmune hepatitis

Autoimmune hepatitis (AIH) is a severe liver disease that affects children and adults worldwide. The diagnosis of AIH relies on increased serum transaminase and immunoglobulin G levels, presence of autoantibodies and interface hepatitis on liver histology. AIH arises in genetically predisposed individuals when a trigger, such as exposure to a virus, leads to a T cell-mediated autoimmune response directed against liver autoantigens; this immune response is permitted by inadequate regulatory immune control leading to a loss of tolerance. AIH responds favourably to immunosuppressive treatment, which should be started as soon as the diagnosis is made. Standard regimens include fairly high initial doses of corticosteroids (prednisone or prednisolone), which are tapered gradually as azathioprine is introduced. For those patients who do not respond to standard treatment, second-line drugs should be considered, including mycophenolate mofetil, calcineurin inhibitors, mechanistic target of rapamycin (mTOR) inhibitors and biologic agents, which should be administered only in specialized hepatology centres. Liver transplantation is a life-saving option for those who progress to end-stage liver disease, although AIH can recur or develop de novo after transplantation. In-depth investigation of immune pathways and analysis of changes to the intestinal microbiota should advance our knowledge of the pathogenesis of AIH and lead to novel, tailored and better tolerated therapies.

Autoantibodies in Autoimmune Liver Disease-Clinical and Diagnostic Relevance

Testing for liver-related autoantibodies should be included in the workup of patients with hepatitis or cholestasis of unknown origin. Although most of these autoantibodies are not disease specific, their determination is a prerequisite to diagnose autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC), and they are components of the diagnostic scoring system in these diseases. In primary sclerosing cholangitis (PSC), on the other hand, autoantibodies are frequently present but play a minor role in establishing the diagnosis. In PSC, however, data on antibodies suggest a link between disease pathogenesis and the intestinal microbiota. This review will focus on practical aspects of antibody testing in the three major autoimmune liver diseases AIH, PBC, and PSC.

The value of serum antibodies in differentiating inflammatory bowel disease, predicting disease activity and disease course in the newly diagnosed patient

BACKGROUND

Data on serum antibodies in untreated adult inflammatory bowel disease (IBD) patients at diagnosis are scarcely available, and results on the stability of antibody presence over time are inconsistent. Our aim was to investigate antibodies in newly diagnosed, untreated IBD patients in relation to disease phenotype and course. Furthermore, we analyzed antibody presence over time.

METHODS

Baseline anti-Saccharomyces cerevisiae antibodies (ASCA), anti-chitobioside carbohydrate antibodies (ACCA), anti-laminaribioside carbohydrate antibodies (ALCA) and anti-mannobioside carbohydrate antibodies (AMCA) were measured with enzyme-linked immunosorbent assays and perinuclear anti-neutrophilic cytoplasmic antibodies (pANCA) was measured by indirect immunofluorescence in serum of 120 untreated IBD patients at diagnosis and 19 healthy controls. Antibodies were related to disease outcomes. Serial measurements were available in 71 patients.

RESULTS

The combination of pANCA and ASCA enabled good discrimination between UC and CD (p = .004). Antibody presence was relatively stable over time, even though there were significant changes in concentrations. There was a trend towards larger fluctuations in concentration with immunosuppressive medication. Baseline pANCA in UC patients correlated with calprotectin values (rho = .545, p = .019) and change in pANCA status over time was associated with disease activity at that moment. No associations were found with antibodies at diagnosis and disease outcomes.

CONCLUSION

Antibody profiles at diagnosis support the distinction between CD and UC. Anti-glycan antibodies are reasonably stable over time, but may fluctuate under the influence of immunosuppressive treatment which may explain the inconsistency in findings hitherto. The appearance or disappearance of pANCA antibodies during follow-up correlated with disease activity in UC and may be used in disease monitoring.

"Autoimmune(-Like)" Drug and Herb Induced Liver Injury: New Insights into Molecular Pathogenesis

Idiosyncratic drug-induced liver injury (DILI) and hepatic injury due to herbal and dietary supplements (HDS) can adapt clinical characteristics of autoimmune hepatitis (AIH), such as the appearance of autoantibodies and infiltration of the liver by immune competent cells. To describe these cases of DILI/HDS, the poorly-defined term "autoimmune(-like)" DILI/HDS came up. It is uncertain if these cases represent a subgroup of DILI/HDS with distinct pathomechanistic and prognostic features different from "classical" DILI/HDS. Besides, due to the overlap of clinical characteristics of "immune-mediated" DILI/HDS and AIH, both entities are not easy to differentiate. However, the demarcation is important, especially with regard to treatment: AIH requires long-term, mostly lifelong immunosuppression, whereas DILI/HDS does not. Only through exact diagnostic evaluation, exclusion of differential diagnoses and prolonged follow-up can the correct diagnosis reliably be made. Molecular mechanisms have not been analysed for the subgroup of "autoimmune(-like)" DILI/HDS yet. However, several pathogenetic checkpoints of DILI/HDS in general and AIH are shared. An analysis of these shared mechanisms might hint at relevant molecular processes of "autoimmune(-like)" DILI/HDS.

Seropositivity and Titers of Anti-Smooth Muscle Actin Antibody Are Associated with Relapse of Type 1 Autoimmune Hepatitis

Background

It is important to avoid relapse in autoimmune hepatitis (AIH) because repeated multiple relapses have been associated with a worse prognosis. However, risk factors for relapse before initiation of treatment are not fully understood. The aim of this study was to find predictive markers for relapse of type 1 AIH.

Material/Methods

We reviewed the records of 53 patients diagnosed with type 1 AIH based on the revised scoring system proposed by the International Autoimmune Hepatitis Group (IAIHG) between 2009 and 2014 at 4 hospitals belonging to the Saga Study Group of Liver Diseases (SASLD). We analyzed the differences in background characteristics between patients with or without relapse.

Results

All patients achieved remission after treatment, and 9 (17%) subsequently relapsed. The relapsed patients were significantly younger and had a higher positive rate of anti-smooth muscle antibody (ASMA) than the non-relapsed patients (100% vs. 25%, P=0.0012). Moreover, relapse rate increased with titer of ASMA, while titer of antinuclear antibody was not associated with relapse rate.

Conclusions

ASMA is a useful predictive marker for relapse of type 1 AIH during or after withdrawal of medical therapy. More careful attention should be paid to immunosuppressive therapy in patients with high titers of ASMA.

Gut barrier failure biomarkers are associated with poor disease outcome in patients with primary sclerosing cholangitis

AIM

To assess the prevalence of a panel of serologic markers that reflect gut barrier dysfunction in a mixed cohort of pediatric and adult primary sclerosing cholangitis (PSC) patients.

METHODS

Sera of 67 PSC patients [median age (range): 32 (5-79) years, concomitant IBD: 67% and cirrhosis: 20%] were assayed for the presence of antibodies against to F-actin (AAA IgA/IgG) and gliadin (AGA IgA/IgG)] and for serum level of intestinal fatty acid-binding protein (I-FABP) by ELISA. Markers of lipopolysaccharide (LPS) exposure [LPS binding protein (LBP)] and various anti-microbial antibodies [anti-OMP Plus IgA and endotoxin core IgA antibody (EndoCAb)] were also determined. Poor disease outcome was defined as orthotopic liver transplantation and/or liver-related death during the follow-up [median: 99 (14-106) mo]. One hundred and fifty-three healthy subjects (HCONT) and 172 ulcerative colitis (UC) patients were the controls.

RESULTS

A total of 28.4%, 28.0%, 9% and 20.9% of PSC patients were positive for AAA IgA, AAA IgG, AGA IgA and AGA IgG, respectively. Frequencies of AAA IgA and AAA IgG (P < 0.001, for both) and AGA IgG (P = 0.01, for both) but not AGA IgA were significantly higher compared to both of the HCONT and the UC groups. In survival analysis, AAA IgA-positivity was revealed as an independent predictor of poor disease outcome after adjusting either for the presence of cirrhosis [HR = 5.15 (1.27-20.86), P = 0.022 or for the Mayo risk score (HR = 4.24 (0.99-18.21), P = 0.052]. AAA IgA-positivity was significantly associated with higher frequency of anti-microbial antibodies (P < 0.001 for EndoCab IgA and P = 0.012 for anti-OMP Plus IgA) and higher level of the enterocyte damage marker (median I-FABPAAA IgA posvsneg: 365 vs 166 pg/mL, P = 0.011), but not with serum LBP level.

CONCLUSION

Presence of IgA type AAA identified PSC patients with progressive disease. Moreover, it is associated with enhanced mucosal immune response to various microbial antigens and enterocyte damage further highlighting the importance of the gut-liver interaction in PSC.

Diagnostic approach to autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease which, if left without treatment, can evolve into cirrhosis and possibly liver failure. The diagnosis of AIH is hampered by the lack of specific and reliable markers of the disease and a number of clinical, biochemical, immunological, histological and genetic factors should be considered to reach a confident diagnosis Areas covered: Clinical expression of AIH, histological features, serological and genetic profiles, differential diagnosis, overlap with other autoimmune liver diseases, assessed on the basis of personal experience and review of published literature in the last 10 years through a systematic Medline search (keywords: autoimmune hepatitis, diagnosis) Expert commentary: Notwithstanding numerous efforts to identify simple and reliable markers of the disease, the diagnosis of AIH is still based on the combination of histological, immunological and biochemical features and often can represent a real challenge for the hepatologist.

Clinical efficacy and safety of integrated traditional Chinese and Western medicine in elderly autoimmune liver disease patients with gastritis

AIM

To evaluate the clinical efficacy and safety of integrated traditional Chinese and Western medicine in elderly autoimmune liver disease patients with gastritis.

METHODS

From January 2010 to June 2016, 56 elderly autoimmune liver disease patients with gastritis were randomly divided into a control group (n = 28) and an observation group (n = 28). Both groups were treated by Western medicine symptomatic support, and the observation group was additionally given Chinese medicine decoction. The clinical efficacy and safety of the two groups were compared.

RESULTS

Before treatment, there was no significant difference in alanine transaminase (ALT) or glutamyl transpeptidase (GGT) between the two groups (P > 0.05). After treatment, ALT (45.31 IU/L ± 10.04 IU/L vs 68.42 IU/L ± 11.46 IU/L) and GGT (41.46 IU/L ± 10.24 IU/L vs 52.17 IU/L ± 11.25 IU/L) were significantly lower in the observation group than in the control group (P < 0.05). There was no significantly difference in the rate of adverse effects between the two groups (P > 0.05).

CONCLUSION

Traditional Chinese medicine decoction combined with Western medicine symptomatic support can improve the liver function of elderly autoimmune liver disease patients with gastritis, without increasing the rate of adverse effects.

Diagnostic autoantibodies for autoimmune liver diseases

Autoimmune liver diseases are conditions of low prevalence that comprise the triad of autoimmune hepatitis, primary biliary cholangitis (cirrhosis) and primary sclerosing cholangitis and their poorly characterised overlapping syndromes. Diagnostic autoantibodies are associated with autoimmune hepatitis and primary biliary cholangitis but not with primary sclerosing cholangitis. Autoantibodies are useful disease markers that facilitate early diagnosis of autoimmune hepatitis and primary biliary cholangitis and allow for therapeutic intervention to prevent progression to liver cirrhosis and associated complications. Adult onset type 1 autoimmune hepatitis is associated with F-actin reactive smooth muscle autoantibody, antinuclear autoantibody in 60% of patients, and autoantibody to SLA/LP in 15–20%. Juvenile onset type 2 autoimmune hepatitis is associated with LKM-1 and LC-1 autoantibodies. Primary biliary cholangitis is associated with a mitochondria-associated autoantibody designated M2 in >90% of patients and with disease-specific antinuclear autoantibodies in 50% that bind to antigens in the nuclear core complex and in multiple nuclear dots. Autoantibodies to the nuclear core complex target gp210, nucleoporin p62 and nuclear lamin B receptor. Autoantibodies to multiple nuclear dots target Sp100 and PML antigens. Liver autoantibodies in asymptomatic patients with normal liver function may precede the subsequent development of overt autoimmune liver disease. For routine diagnostic immunology laboratories, initial screening for liver autoantibodies by immunofluorescence remains the method of choice with confirmation for reactivity with their target antigen by enzyme-linked immunosorbent assay (ELISA) or line blot when required.

Extracellular Actin in Health and Disease

This review considers the functions of extracellular actin - cell surface bound, associated with extracellular matrix, or freely circulating. The role of this protein in different pathological processes is analyzed: its toxic effects and involvement in autoimmune diseases as an autoantigen. The extracellular actin clearance system and its role in protection against the negative effects of actin are characterized. Levels of free-circulating actin, anti-actin immunoglobulins, and components of the actin clearance system as prognostic biomarkers for different diseases are reviewed. Experimental approaches to protection against excessive amounts of free-circulating F-actin are discussed.

Concurrent extrahepatic autoimmunity in autoimmune hepatitis: implications for diagnosis, clinical course and long-term outcomes

BACKGROUND

Concurrent extrahepatic autoimmune disease (CEHAID) associated with autoimmune hepatitis (AIH) have been incorporated into the diagnostic criteria stipulated by the International Autoimmune Hepatitis Group (IAIHG). Large comprehensive cohort data on the extrahepatic autoimmunity in AIH remain scanty.

AIM

To systematically assess features and clinical impact of CEHAID on AIH.

METHODS

Clinical records of 562 patients with AIH from two tertiary centres in the UK were retrospectively reviewed.

RESULTS

Prevalence of CEHAID in patients with AIH was 42%. Autoimmune thyroid disease was the commonest CEHAID associated with AIH (101/562, 18%). Autoimmune skin diseases were more prevalent in AIH-2 than AIH-1 (21.9% vs 7%, P=.009). Personal history of CEHAID was more commonly found in AIH patients with than without first-degree family history of CEHAID [48/86 (55.8%) vs 169/446 (37.9%), P=.002]. AIH patients with CEHAID were more often women (85.2% vs 76.1%, P=.008), had higher post-treatment IAIHG score (22 vs 20, P<.001), less reactivity to smooth muscle antibodies (49.8% vs 65%, P<.001), more likely to have mild fibrosis at diagnosis (20.9% vs 6.5%, P<.001) and less often had ascites (6.3% vs 13.6%, P=.008) and coagulopathy (1.18 vs 1.27, P=.013) at presentation. Presence of CEHAID, however, did not significantly affect disease progression, prognosis and survival in AIH.

CONCLUSIONS

Our study confirms the strong association of CEHAID with AIH. Association between personal and familial extrahepatic autoimmunity especially among first-degree relatives was evident. Presence of CEHAID may influence clinical phenotype of AIH at presentation, but without notable impact on the long-term clinical outcomes.

Predictive factors of poor response to therapy in Autoimmune Hepatitis

AIM

To evaluate "ex ante" the predictive factors of incomplete/absent response to the standard therapy in a well characterized series of Autoimmune Hepatitis (AIH) patients from Italy.

METHODS

Of 282 AIH patients screened from our database 166 (59%) had a sustained response and 116 (41%) had an incomplete/absent response to the therapy; all patients were analyzed for the clinical, serological and histological parameters at diagnosis.

RESULTS

The patients with incomplete/absent response were characterized by significantly younger age (30 aa vs 42 aa p=0.001) and a significantly higher frequency of cirrhosis at diagnosis than patients who had a complete response to therapy (26% vs 3% p<0.0001); furthermore, patients with incomplete/absent response were distinguished from those with a complete response for significantly lower serum levels of both AST (7.9×upper normal limit [unl] vs 13×unl p<0.005) and ALT (10.9×unl vs 18×unl p=0.002) at diagnosis, and by an increase in IgG serum levels (1.43×unl vs 1.27×unl p=0.009). After stepwise logistic regression, cirrhosis at diagnosis (p=0.003, OR 0.12, 95% CI 0.03-0.49) and younger age (p=0.001, OR 1.03, 95% CI 1.01-1.05) represent two independent variables of incomplete/absent response.

CONCLUSIONS

Younger age and cirrhosis are predictive of lack of response to the standard therapy in AIH patients.

Autoimmune Liver Disease Post-Liver Transplantation: A Summary and Proposed Areas for Future Research

Autoimmune liver diseases (AILD) are rare diseases with a reported prevalence of less than 50 per 100 000 population. As the research landscape and our understanding of AILDs and liver transplantation evolves, there remain areas of unmet needs. One of these areas of unmet needs is prevention of disease recurrence after liver transplantation. Disease recurrence is not an insignificant event because allograft loss with the need for retransplantation can occur. Patients transplanted for AILD are more likely to experience acute rejection compared to those transplanted for non-AILD, and the reason(s) behind this observation is unclear. Tasks for the future include a better understanding of the pathogenesis of AILD, definition of the precise pathogenetic mechanisms of recurrent AILD, and development of strategies that can identify recipients at risk for disease recurrence. Importantly, the role of crosstalk between alloimmune responses and autoimmune responses in AILD is an important area that needs further study.

This article reviews the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements, and future scientific goals to enhance our understanding of these diseases.

A review of the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements and future scientific goals to enhance our understanding of these diseases.

Clinical Characteristics and Prognosis in Children and Adolescents With Autoimmune Hepatitis and Overlap Syndrome

Objectives:

This is a cohort study of 134 children and adolescents with a known diagnosis of autoimmune hepatitis (AIH). During follow‐up, some of them developed autoimmune sclerosing cholangitis (ASC). This study describes the characteristics of the patients upon diagnosis, and their response to treatment and any complications, and compares the patients who developed ASC during follow‐up (ASC group) with those who did not (AIH group).

Methods:

A total of 73.1% of the patients were girls with a median age upon diagnosis of 10.41 (7.41–12.53) years.

Results:

Of 134 patients, 28 (20.9%) developed cholestatic manifestations, with features of ASC. A few differences were observed between the AIH and ASC groups when they were analyzed by χ2 test, such as the smaller predominance of girls in ASC group (P = 0.04), and more common asymptomatic presentation in the ASC group (P = 0.01). Cirrhosis was observed in 68% of biopsies, with no significant difference between groups (P = 0.43). Of 16 deaths, 15 were in the AIH group and 1 in the ASC group (P = 0.22). Of 11 transplants, 10 were in the AIH group and one in the ASC group (P = 0.53). The presence of cirrhosis at baseline was associated with a smaller survival probability (P = 0.015). The survival rate by Kaplan‐Meier method was 94% at 5 years and 80% at 10 years, and was similar in both the groups (P = 0.08).

Conclusions:

No statistically significant difference was observed between the groups in relation to prognosis and response to treatment.

Diagnosis and Management of Autoimmune Hepatitis: Current Status and Future Directions

Autoimmune hepatitis is characterized by autoantibodies, hypergammaglobulinemia, and interface hepatitis on histological examination. The features lack diagnostic specificity, and other diseases that may resemble autoimmune hepatitis must be excluded. The clinical presentation may be acute, acute severe (fulminant), or asymptomatic; conventional autoantibodies may be absent; centrilobular necrosis and bile duct changes may be present; and the disease may occur after liver transplantation or with features that suggest overlapping disorders. The diagnostic criteria have been codified, and diagnostic scoring systems can support clinical judgment. Nonstandard autoantibodies, including antibodies to actin, α-actinin, soluble liver antigen, perinuclear antineutrophil antigen, asialoglycoprotein receptor, and liver cytosol type 1, are tools that can support the diagnosis, especially in patients with atypical features. Prednisone or prednisolone in combination with azathioprine is the preferred treatment, and strategies using these medications in various doses can ameliorate treatment failure, incomplete response, drug intolerance, and relapse after drug withdrawal. Budesonide, mycophenolate mofetil, and calcineurin inhibitors can be considered in selected patients as frontline or salvage therapies. Molecular (recombinant proteins and monoclonal antibodies), cellular (adoptive transfer and antigenic manipulation), and pharmacological (antioxidants, antifibrotics, and antiapoptotic agents) interventions constitute future directions in management. The evolving knowledge of the pathogenic pathways and the advances in technology promise new management algorithms.

Brazilian society of hepatology recommendations for the diagnosis and management of autoimmune diseases of the liver

ABSTRACT In order to draw evidence-based recommendations concerning the management of autoimmune diseases of the liver, the Brazilian Society of Hepatology has sponsored a single-topic meeting in October 18th, 2014 at São Paulo. An organizing committee comprised of seven investigators was previously elected by the Governing Board to organize the scientific agenda as well as to select twenty panelists to make a systematic review of the literature and to present topics related to the diagnosis and treatment of autoimmune hepatitis, primary sclerosing cholangitis, primary biliary cirrhosis and their overlap syndromes. After the meeting, all panelists gathered together for the discussion of the topics and the elaboration of those recommendations. The text was subsequently submitted for suggestions and approval of all members of the Brazilian Society of Hepatology through its homepage. The present paper is the final version of the reviewed manuscript organized in topics, followed by the recommendations of the Brazilian Society of Hepatology.

The clinical phenotypes of autoimmune hepatitis: A comprehensive review

Autoimmune hepatitis (AIH) fulfills the generally accepted contemporary criteria of an autoimmune liver disease: the presence of autoantibodies and autoreactive T cells, a female gender bias, association with other autoimmune diseases, response to immunosuppressive therapy and strong associations with the major histocompatibility complex HLA loci. It occurs worldwide in both children and adults and is marked by both etiopathogenic and clinical heterogeneity, differing from the other putative autoimmune liver diseases, primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), albeit occasionally presenting with overlapping features of PBC or PSC. Although diagnostic criteria have been established and validated, there are still major issues to be clarified due to its variability, such as autoantibody-negative AIH, drug-induced AIH, AIH sharing features with PBC or PSC, and post-transplant de novo AIH. In view of the diverse presentations and courses, including classical chronic onset, acute and acute severe onset, cirrhosis and decompensated cirrhosis, individualized management of patients is indicated. Each patient should receive a personalized analysis of the benefits and side effect risks of drugs. Herein we describe a comprehensive review of the clinical phenotypes of AIH underscoring its clinical heterogeneity.

A novel "humanized mouse" model for autoimmune hepatitis and the association of gut microbiota with liver inflammation

Autoimmune hepatitis (AIH) in humans is a severe inflammatory liver disease characterized by interface hepatitis, the presence of circulating autoantibodies, and hyper-gammaglobulinemia. There are two types of AIH, type 1 (AIH-1) and type 2 (AIH-2), characterized by distinct autoimmune serology. Patients with AIH-1 are positive for anti-smooth muscle and/or antinuclear autoantibodies, whereas patients with AIH-2 have anti-liver kidney microsomal type 1 and/or anti-liver cytosol type 1 autoantibodies. Cytochrome P4502D6 is the antigenic target of anti-liver kidney microsomal type 1, and formiminotransferase cyclodeaminase is the antigenic target of anti-liver cytosol type 1. It is known that AIH, both types 1 and 2, is strongly linked to the human leukocyte antigen (HLA) alleles -DR3, -DR4, and -DR7. However, direct evidence of the association of HLA with AIH is lacking. We developed a novel mouse model of AIH using the HLA-DR3 transgenic mouse on the nonobese-diabetic background by immunization of HLA-DR3- and HLA-DR3+ nonobese-diabetic mice with a DNA plasmid, coding for human cytochrome P4502D6/formiminotransferase cyclodeaminase fusion protein. Immunization with cytochrome P4502D6/formiminotransferase cyclodeaminase leads to a sustained elevation of alanine aminotransferase, development of antinuclear autoantibodies and anti-liver kidney microsomal type 1/anti-liver cytosol type 1 autoantibodies, chronic immune cell infiltration, and parenchymal fibrosis on liver histology in HLA-DR3+ mice. Immunized mice also showed an enhanced T helper 1 immune response and paucity of the frequency of regulatory T cells in the liver. Moreover, HLA-DR3+ mice with exacerbated AIH showed reduced diversity and total load of gut bacteria.

CONCLUSION

Our humanized animal model has provided a novel experimental tool to further elucidate the pathogenesis of AIH and to evaluate the efficacy and safety of immunoregulatory therapeutic interventions in vivo.