Acute autoimmune hepatitis: many open questions

Autoimmune Hepatitis: From Evolution to Current Status-A Pathologist's Perspective

Autoimmune hepatitis (AIH) is a chronic, relapsing and remitting, immune-mediated liver disease that progresses to cirrhosis if left untreated. A significant number of patients may present with acute hepatitis or acute liver failure, which are often misdiagnosed as toxic liver injury. AIH shows a preponderance in young women but may be seen in children and the elderly. Diagnosis requires the integration of clinical, biochemical, and serologic parameters, along with supportive liver histology and exclusion of other causes of liver disease. Liver biopsy is a prerequisite for diagnosis of AIH, to assess severity and stage of disease, exclude other entities, and recognize any concurrent morbidities. No single biomarker or histologic feature is pathognomonic for AIH. The diagnostic and histologic criteria have undergone several modifications since the original scoring system was proposed by the International Autoimmune Hepatitis Group (IAIHG) in 1993. Recently, the IAIHG has proposed consensus recommendations for histologic criteria, relevant for both acute and chronic AIH. This review article will describe the evolving diagnostic criteria for AIH, with their limitations and utility, and with an emphasis on the role of liver histology in the diagnosis and management of AIH.

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.

Early liver transplantation for corticosteroid non-responders with acute severe autoimmune hepatitis: The SURFASA score

BACKGROUND & AIMS

In acute severe autoimmune hepatitis (AS-AIH), the optimal timing for liver transplantation (LT) remains controversial. The objectives of this study were to determine early predictive factors for a non-response to corticosteroids and to propose a score to identify patients in whom LT is urgently indicated.

METHODS

This was a retrospective, multicenter study (2009-2016). A diagnosis of AS-AIH was based on: i) Definite or probable AIH based on the simplified IAIHG score; ii) international normalized ratio (INR) ≥1.5 and/or bilirubin >200 μmol/L; iii) No previous history of AIH; iv) Histologically proven AIH. A treatment response was defined as LT-free survival at 90 days. The evolution of variables from corticosteroid initiation (day-D0) to D3 was estimated from: Δ%3 = (D3-D0)/D0.

RESULTS

A total of 128 patients were included, with a median age of 52 (39-62) years; 72% were female. Overall survival reached 88%. One hundred and fifteen (90%) patients received corticosteroids, with a LT-free survival rate of 66% at 90 days. Under multivariate analysis, D0-INR (odds ratio [OR] 6.85; 95% CI 2.23-21.06; p <0.001), Δ%3-INR ≥0.1% (OR 6.97; 95% CI 1.59-30.46; p <0.01) and Δ%3-bilirubin ≥-8% (OR 5.14; 95% CI 1.09-24.28; p <0.04) were predictive of a non-response. The SURFASA score: -6.80+1.92∗(D0-INR)+1.94∗(Δ%3-INR)+1.64∗(Δ%3-bilirubin), created by combining these variables, was highly predictive of LT or death (AUC = 0.93) (88% specificity; 84% sensitivity) with a cut-off point of <-0.9. Below this cut-off, the chance of responding was 75%. With a score higher than 1.75, the risk of dying or being transplanted was between 85% and 100%.

CONCLUSION

In patients with AS-AIH, INR at the introduction of corticosteroids and the evolution of INR and bilirubin are predictive of LT or death. Within 3 days of initiating corticosteroids, the SURFASA score can identify non-responders who require a referral for LT. This score needs to be validated in a prospective cohort.

LAY SUMMARY

The management of patients with acute severe autoimmune hepatitis is highly challenging, particularly regarding their early referral for liver transplantation. We found that international normalized ratio at the initiation of corticosteroid therapy and the evolution of international normalized ratio and bilirubin values after 3 days of therapy were highly predictive of liver transplantation or death. We are thus proposing a score that combines these variables and identifies patients in whom liver transplantation is urgently required.

Autoimmune hepatitis-is histology conclusive?

Liver biopsy is an essential and necessary element in the diagnosis and management of autoimmune hepatitis, and is of very special importance in the scoring system for diagnosis. Histopathology shows moderate to severe inflammatory infiltrates with abundant plasma cells in the enlarged portal tracts with interface hepatitis and moderate to severe necroinflammatory lesions in the lobules with lymphoplasmacytic reaction. Regeneration develops with rosette formation and regenerative nodules. One important issue is the differentiation between acute onset of autoimmune hepatitis and a flare up of chronic disease; this cannot be diagnosed in some cases clinically and therefore requires a biopsy to evaluate the stage of the disease. There are some variants of the disease with cholestatic features such as autoantibody negative autoimmune hepatitis and giant cell hepatitis as well as overlap syndromes with primary biliary cholangitis and primary sclerosing cholangitis. Clinically, three types of autoimmune hepatitis are differentiated according to autoantibody formation and the clinical picture, however, histopathologically there is no difference between these three types. Differential diagnosis of autoimmune hepatitis includes drug-induced liver injury with minocycline, alpha methyldopa, nitrofurantoin and checkpoint inhibitors such as infliximab. Wilson´s disease is also an important differential diagnosis especially in young adults. A liver biopsy is mandatory to confirm the diagnosis of autoimmune hepatitis but histopathology alone is not conclusive.

miRNAs Signatures In Patients With Acute Liver Injury: Clinical Concerns and Correlations

Non-coding RNAs can be highly exploited for their biological significance in living systems. miRNAs are in the upstream position of cellular regulation cascade and hold merit in its state. A plethora of information is available on a wide variety of miRNAs that undergo alterations in experimentally induced models of liver injuries. The underlying mechanisms governed by these miRNAs have been inferred through cellbased experiments but the scientific knowledge on miRNA signatures in patients with liver injury are primordial and lack scientific clarity. Hence, it is crucial to get insight into the status and synergy of miRNAs in patients, with varying degrees of acute toxic manifestations in the liver. Though some miRNAs are being investigated in clinical trials, a major research lacuna exists with regard to the functional role of other miRNAs in liver diseases. This review article is a meticulous compilation of disease based or drug/alcohol based acute liver injuries in patients and resultant alteration in their miRNA profile. Investigative reports on underlying miRNA-liver crosstalk in cell-based or murine models are also discussed herein to draw a correlation with clinical findings.

Plasmacytoid dendritic cells protect against immune-mediated acute liver injury via IL-35

Acute liver failure (ALF) is a life-threatening condition, and liver transplantation is the only therapeutic option. Although immune dysregulation is central to its pathogenesis, the precise mechanism remains unclear. Here, we show that the number of peripheral and hepatic plasmacytoid DCs (pDCs) decrease during acute liver injury in both humans and mice. Selective depletion of pDCs in Siglechdtr/+ mice exacerbated concanavalin A-induced acute liver injury. In contrast, adoptively transferred BM-derived pDCs preferentially accumulated in the inflamed liver and protected against liver injury. This protective effect was independent of TLR7 and TLR9 signaling, since a similar effect occurred following transfer of MyD88-deficient pDCs. Alternatively, we found an unexpected immunosuppressive role of pDCs in an IL-35-dependent manner. Both Il12a and Ebi3, heterodimeric components of IL-35, were highly expressed in transferred pDCs and CD4+CD25+ Tregs. However, the protective effect of pDC transfer was completely lost in mice depleted of Tregs by anti-CD25 antibody. Moreover, pDCs derived from IL-35-deficient mice had less of a protective effect both in vivo and in vitro even in the presence of Tregs. These results highlight a unique aspect of pDCs in association with Tregs, serving as a guide for immunotherapeutic options in ALF.

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

ABSTRACT 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.

Hellenic Association for the Study of the Liver Clinical Practice Guidelines: Autoimmune hepatitis

Autoimmune hepatitis (AIH) is a relatively rare acute or chronic liver disease of unknown etiology characterized by large heterogeneity. Its distribution is global, covering all ages, both sexes and all ethnic groups. The aim of the present Clinical Practice Guidelines (CPG) of the Hellenic Association for the Study of the Liver was to provide updated guidance and help to gastroenterologists, hepatologists, internists and general practitioners for AIH diagnosis and management. AIH diagnosis is based on clinicopathological characteristics: namely, polyclonal hypergammaglobulinemia, particularly of immunoglobulin G (IgG), circulating autoantibodies, interface hepatitis on liver histology, absence of viral hepatitis, and a favorable response to immunosuppression. Clinical manifestations at disease onset are variable, ranging from asymptomatic to the acute/severe form. Aminotransferase and bilirubin levels vary, while the presence of hepatitis at the histological level is a prerequisite for diagnosis. Autoantibodies are the hallmark for AIH diagnosis; therefore, the CPG describe the appropriate serological algorithm for their detection. AIH therapy should aim to achieve complete biochemical (normalization of IgG and aminotransferases) and histological remission. All patients who have active disease, even those with cirrhosis, should be treated with individualized and response-guided induction therapy using prednisolone in combination with azathioprine or mycophenolate mofetil as first-line therapy. Immunosuppression should be given for at least 3 years and for at least 2 years after the achievement of complete biochemical response, while a liver biopsy should be recommended before treatment discontinuation. Current CPG are also provided for several specific conditions and difficult-to-treat patients.

Autoimmune Hepatitis in the Asia-Pacific Area

Autoimmune hepatitis has been considered as a relatively rare immunological liver disease, especially in the Asia-Pacific area. Although the diagnosis criteria and immunosuppressive treatment regimens have been established, there are still some challenges. According to the different presentations, the personalized management of patients who suffer from this disease, including those with chronic or acute severe onset, the autoantibody-negative phenotype and cirrhosis are necessarily descriptive. Each subgroup of patients should receive an individualized therapy. Here, we review the recent studies of autoimmune hepatitis, mainly focusing on the epidemiology and genetics, personalized diagnostics, individualized treatment strategies, special subgroups and outcomes. Most of the research in the literature is based on Japanese and Chinese populations.

Clinical and Pathological Characteristics of Autoimmune Hepatitis with Acute Presentation

Aim. To study the differences between acute presentation-autoimmune hepatitis (A-AIH) and chronic autoimmune hepatitis (C-AIH). Methods. Through long-term follow-up, 80 patients were included in our study by using the revised international autoimmune hepatitis group (IAIHG) score and were divided into acute and chronic groups for comparison. Results. No significant difference was found in the gender, age, IAIHG score (pretreatment/posttreatment), definite diagnosis rate, extrahepatic autoimmune disease, onset time, or treatment before biopsy between the acute and chronic groups. In terms of clinical symptoms, A-AIH patients were more prone to jaundice, anorexia, yellow urine, and detesting oil than C-AIH patients, but melena only occurred in chronic group (P < 0.05). The acute group exhibited more severe injury upon histological evaluation, with lobular inflammation and bile duct injury, especially central necrosis of the lobule, more pronounced in this group (P < 0.05). Conclusion. A-AIH had manifestations of acute hepatitis and presented cholestasis. Serum indicators could preliminarily distinguish A-AIH and C-AIH. Histologically, the primary manifestation of A-AIH was lobular inflammation, which was usually accompanied by lobular central necrosis. For the diagnosis of A-AIH, more attention should be paid to long-term follow-up. This study was registered at ClinicalTrials.gov (identifier: NCT02994537).

Autoimmune hepatitis: From current knowledge and clinical practice to future research agenda

Autoimmune hepatitis is a chronic inflammatory liver disease. Unknown triggers lead to a mainly T cell-mediated immune response targeting the liver, the main auto-antigen of which has not been identified yet. The diagnosis of autoimmune hepatitis is based on the elevation of immunoglobulin G/hypergammaglobulinemia, detection of characteristic autoantibodies as well as a typical pattern on liver histology. Exclusion of other causes of hepatitis and response to immunosuppressive treatment support the diagnosis of autoimmune hepatitis. The mainstay of autoimmune hepatitis treatment has, from its first description to the current time, consisted of predniso(lo)ne to induce remission, in combination with azathioprine, which is used to maintain it. Nonetheless, side effects and non-response with ongoing inflammation despite standard therapy demand treatment alternatives. Only through a better understanding of the pathogenesis of autoimmune hepatitis can a more selective and effective treatment be offered to patients in the future. Until this goal is reached, improvement of diagnostic approaches and optimization of current therapy rank highest on the research agenda for autoimmune hepatitis.

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.