Optimizing thiopurine therapy in autoimmune hepatitis: A multicenter study on monitoring metabolite profiles and co-therapy with allopurinol.

BACKGROUND AND AIMS: In autoimmune hepatitis, achieving complete biochemical remission (CBR) with current weight-based thiopurine dosing is challenging. We investigated whether patients could be stratified regarding CBR according to a target range of thiopurine metabolites. Moreover, we explored the effects of azathioprine dosage increases and co-therapy of allopurinol with low-dose thiopurines on metabolite profiles and treatment response. APPROACH AND RESULTS: The relation between metabolites and treatment response was assessed in 337 individuals from 4 European centers. In a global, cross-sectional analysis, active metabolites 6-thioguanine nucleotides (6TGN) were similar in those with and without CBR. However, analyzing patients with sequential measurements over 4 years (N = 146) revealed higher average 6TGN levels in those with stable CBR (260 pmol/0.2 mL) compared to those failing to maintain CBR (181 pmol/0.2 mL; p = 0.0014) or never achieving CBR (153 pmol/0.2 mL; p < 0.0001), with an optimal 6TGN cutoff of ≥223 pmol/0.2 mL (sensitivity: 76% and specificity: 78%). Only 42% exhibited 6TGN ≥223 pmol/0.2 mL following weight-based dosing, as doses weakly correlated with 6TGN but with 6-methylmercaptopurine (6MMP), a metabolite associated with toxicity. Azathioprine dose increases led to preferential 6MMP formation (+127% vs. 6TGN +34%; p < 0.0001). Conversely, adding allopurinol to thiopurines in difficult-to-treat patients (N = 36) raised 6TGN (168→321 pmol/0.2 mL; p < 0.0001) and lowered 6MMP (2125→184 pmol/0.2 mL; p < 0.0001), resulting in improved transaminases in all patients and long-term CBR in 75%. CONCLUSIONS: Maintaining CBR in autoimmune hepatitis was associated with 6TGN ≥223 pmol/0.2 mL. For patients who fail to achieve CBR and therapeutic 6TGN levels despite thiopurine dose increase due to preferential 6MMP formation, comedication of allopurinol alongside low-dose thiopurines represents an efficient alternative.

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.

SARS-CoV-2 mRNA vaccines do not worsen autoimmunity in patients with autoimmune liver diseases.

INTRODUCTION AND AIMS: mRNA vaccines against Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) infection have been associated with immune-related adverse reactions. We aimed at investigating whether SARS-CoV-2 vaccines may worsen autoimmune reactions in patients with autoimmune liver diseases. METHODS: We centrally tested a large panel of liver- and non-liver-related autoantibodies in patients with primary biliary cholangitis (PBC), autoimmune hepatitis (AIH), primary sclerosing cholangitis (PSC), and in healthcare workers (HW) before and after SARS-CoV-2 mRNA vaccines. RESULTS: 49 PBC, 35 AIH, 9 PSC and 38 HW were included. The proportion of subjects with at least one autoantibody positivization after vaccination was 11 % for HW, 37 % for AIH, 35 % for PBC and 56 % for PSC patients, patients having a significantly higher frequency of positivization as compared to HW. The proportion of seropositive subjects before vaccination who had at least one autoantibody negativization was 25 % for HW, 57 % for AIH, 40 % for PBC and 50 % for PSC, AIH patients having a significantly higher frequency of negativization as compared to HW. In the AIH group, the number of autoantibody negativizations was higher than the number of positivizations. The BNT162b2 vaccine was associated with a higher risk of developing new autoantibodies as compared to the mRNA-1273 vaccine. No new-onset autoimmune disease was observed after one year. One AIH patient had a relapse after vaccination. CONCLUSION: mRNA SARS-CoV-2 vaccines do not induce short-term worsening of autoimmunity in patients with autoimmune liver diseases.

Hoigné's syndrome, an uncommon mimicker of anaphylaxis: Systematic literature review.

The term Hoigné's syndrome denotes a mimicker of anaphylaxis, which occurs immediately after the parenteral administration of a drug and is likely caused by non-thrombotic pulmonary and systemic drug micro-embolization. It has so far been documented uniquely in case reports and small case series. Because this condition has never been systematically evaluated, we performed a structured literature review (pre-registered as CRD42023392962). The search was carried out in Excerpta Medica, National Library of Medicine, and Google Scholar. Cases with features consistent with anaphylaxis, urticaria, angioedema, asthma, syncope, anxiety, or panic attack triggered by needle phobia, and local anesthetic systemic toxicity were excluded. For the final analysis, we retained reports published between 1951 and 2021, which presented 247 patients with Hoigné's syndrome: 37 children and 211 adults with a male: female ratio of 2.1 : 1.0. The patients presented within 1 min after parenteral administration of a drug (intramuscular penicillin in 90 % of the cases) with chest discomfort, shortness of breath, fear of death, psychomotor agitation, and auditory or visual hallucinations and impairment. Recovery occurred within 30 min. The diagnosis of Hoigné's syndrome was also established in five patients 66-91 years of age with pre-existing cardiovascular or pulmonary diseases, who suddenly died after the administration of penicillin despite not exhibiting the aforementioned symptoms. It was therefore speculated that pulmonary drug micro-embolization induced a lethal cardiovascular compromise in these individuals. Histologic investigations supporting this hypothesis were performed in only one case. The diagnosis of Hoigné's pulmonary drug micro-embolization was established also in five patients with pre-existing cardiovascular or pulmonary diseases, who suddenly died after the administration of penicillin despite not exhibiting the afore mentioned symptoms. Histologic investigations supporting this hypothesis were performed in only one case. In conclusion, Hoigné's syndrome is an uncommon non-immune-mediated reaction. This report seeks to promote broader awareness and knowledge regarding this alarming mimicker of anaphylaxis. Diagnosis relies solely on clinical evaluation.

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

BACKGROUND & AIMS: Liver injury after COVID-19 vaccination is very rare and shows clinical and histomorphological similarities with autoimmune hepatitis (AIH). Little is known about the pathophysiology of COVID-19 vaccine-induced liver injury (VILI) and its relationship to AIH. Therefore, we compared VILI with AIH. METHODS: Formalin-fixed and paraffin-embedded liver biopsy samples from patients with VILI (n = 6) and from patients with an initial diagnosis of AIH (n = 9) were included. Both cohorts were compared by histomorphological evaluation, whole-transcriptome and spatial transcriptome sequencing, multiplex immunofluorescence, and immune repertoire sequencing. RESULTS: Histomorphology was similar in both cohorts but showed more pronounced centrilobular necrosis in VILI. Gene expression profiling showed that mitochondrial metabolism and oxidative stress-related pathways were more and interferon response pathways were less enriched in VILI. Multiplex analysis revealed that inflammation in VILI was dominated by CD8+ effector T cells, similar to drug-induced autoimmune-like hepatitis. In contrast, AIH showed a dominance of CD4+ effector T cells and CD79a+ B and plasma cells. T-cell receptor (TCR) and B-cell receptor sequencing showed that T and B cell clones were more dominant in VILI than in AIH. In addition, many T cell clones detected in the liver were also found in the blood. Interestingly, analysis of TCR beta chain and Ig heavy chain variable-joining gene usage further showed that TRBV6-1, TRBV5-1, TRBV7-6, and IgHV1-24 genes are used differently in VILI than in AIH. CONCLUSIONS: Our analyses support that SARS-CoV-2 VILI is related to AIH but also shows distinct differences from AIH in histomorphology, pathway activation, cellular immune infiltrates, and TCR usage. Therefore, VILI may be a separate entity, which is distinct from AIH and more closely related to drug-induced autoimmune-like hepatitis. IMPACT AND IMPLICATIONS: Little is known about the pathophysiology of COVID-19 vaccine-induced liver injury (VILI). Our analysis shows that COVID-19 VILI shares some similarities with autoimmune hepatitis, but also has distinct differences such as increased activation of metabolic pathways, a more prominent CD8+ T cell infiltrate, and an oligoclonal T and B cell response. Our findings suggest that VILI is a distinct disease entity. Therefore, there is a good chance that many patients with COVID-19 VILI will recover completely and will not develop long-term autoimmune hepatitis.

Nomenclature, diagnosis and management of drug-induced autoimmune-like hepatitis (DI-ALH): An expert opinion meeting report.

Drug-induced liver injury (DILI) can mimic almost all other liver disorders. A phenotype increasingly ascribed to drugs is autoimmune-like hepatitis (ALH). This article summarises the major topics discussed at a joint International Conference held between the Drug-Induced Liver Injury consortium and the International Autoimmune Hepatitis Group. DI-ALH is a liver injury with laboratory and/or histological features that may be indistinguishable from those of autoimmune hepatitis (AIH). Previous studies have revealed that patients with DI-ALH and those with idiopathic AIH have very similar clinical, biochemical, immunological and histological features. Differentiating DI-ALH from AIH is important as patients with DI-ALH rarely require long-term immunosuppression and the condition often resolves spontaneously after withdrawal of the implicated drug, whereas patients with AIH mostly require long-term immunosuppression. Therefore, revision of the diagnosis on long-term follow-up may be necessary in some cases. More than 40 different drugs including nitrofurantoin, methyldopa, hydralazine, minocycline, infliximab, herbal and dietary supplements (such as Khat and Tinospora cordifolia) have been implicated in DI-ALH. Understanding of DI-ALH is limited by the lack of specific markers of the disease that could allow for a precise diagnosis, while there is similarly no single feature which is diagnostic of AIH. We propose a management algorithm for patients with liver injury and an autoimmune phenotype. There is an urgent need to prospectively evaluate patients with DI-ALH systematically to enable definitive characterisation of this condition.

Autoimmune markers and vascular immune deposits in Finkelstein-Seidlmayer vasculitis: Systematic literature review.

Finkelstein-Seidlmayer vasculitis, also called acute hemorrhagic edema of young children or infantile immunoglobulin A vasculitis, is habitually a benign skin-limited small vessel leukocytoclastic vasculitis that mainly affects infants 24 months or less of age. Since this disease is commonly triggered by an infection, an immune-mediated origin has been postulated. To better appreciate the possible underlying immune mechanism of this vasculitis, we addressed circulating autoimmune markers and vascular immune deposits in patients contained in the Acute Hemorrhagic Edema BIbliographic Database, which incorporates all original reports on Finkelstein-Seidlmayer vasculitis. A test for at least one circulating autoimmune marker or a vascular immune deposit was performed in 243 cases. Subunits of complement system C4 resulted pathologically reduced in 4.7% and C3 in 1.4%, rheumatoid factor was detected in 6.1%, and antinuclear antibodies in 1.9% of cases. Antineutrophil cytoplasmic antibodies were never demonstrated. Immunofluorescence studies were performed on 125 skin biopsy specimens and resulted positive for complement subunits in 46%, fibrinogen in 45%, immunoglobulin A in 25%, immunoglobulin M in 24%, immunoglobulin G in 13%, and immunoglobulin E in 4.2% of cases. Infants testing positive for vascular immunoglobulin A deposits did not present a higher prevalence of systemic involvement or recurrences, nor a longer disease duration. In conclusion, we detected a very low prevalence of circulating autoimmune marker positivity in Finkelstein-Seidlmayer patients. Available immunofluorescence data support the notion that immune factors play a relevant role in this vasculitis. Furthermore, vascular immunoglobulin A deposits seem not to play a crucial role in this disease.

Hepatic safety and efficacy of immunomodulatory drugs used in patients with autoimmune hepatitis.

BACKGROUND AND AIMS: There is little data on the hepatic efficacy and safety of immunomodulatory drugs used in patients with autoimmune hepatitis (AIH), despite their established use in dermatology, rheumatology and inflammatory bowel diseases (IBD). Our aim was to collect real-life data on the experience of expert centres in treating AIH patients with these drugs, considered unconventional for AIH management. METHODS: Online survey among hepatology centres being part of the European Reference Network on Hepatological Diseases (ERN RARE-LIVER). RESULTS: 25 AIH patients have been reported. Ten were female, median age at diagnosis was 28 years; median follow-up was 17 months. All had initially received AIH-standard treatment. AIH-unconventional treatment was initiated for concomitant autoimmune diseases in 15 cases: nine for IBD (five vedolizumab and four ustekinumab), and one each for following diseases: autoinflammatory syndrome (tocilizumab), chronic urticaria (omalizumab), rheumatoid arthritis (abatacept), psoriasis (guselkumab), psoriatric arthritis (secukinumab, followed by ustekinumab) and alopecia (ruxolitinib). Three patients were treated with immunomodulatory drugs for side effects of previous treatments, including two patients with IBD treated with vedolizumab and ustekinumab, respectively, and one treated with belimumab. At the end of follow-up, 13 patients were in complete biochemical response, the patient on omalizumab had a relapse, and four patients with concomitant IBD had insufficient response. Seven patients were treated for lack of biochemical remission, of whom six with belimumab, all initially reaching complete biochemical response, but five relapsing during follow-up; and one with secukinumab, having concomitant rheumatoid arthritis and ankylosing spondylitis, reaching complete biochemical response. Only the patient on abatacept received unconventional treatment as monotherapy. Side effects were reported in two patients on belimumab: one recurrent soft tissue infections, one fatigue and arthralgia. CONCLUSION: Among 25 AIH patients who were treated with immunomodulatory drugs for different reasons, the majority had a fovorable course, relapse was frequent in difficult-to-treat patients who received belimumab, and four with concomitant IBD had insufficient response.

Liver injury after SARS-CoV-2 vaccination: Features of immune-mediated hepatitis, role of corticosteroid therapy and outcome.

BACKGROUND AND AIMS: A few case reports of autoimmune hepatitis-like liver injury have been reported after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. We evaluated clinical features, treatment response and outcomes of liver injury following SARS-CoV-2 vaccination in a large case series. APPROACH AND RESULTS: We collected data from cases in 18 countries. The type of liver injury was assessed with the R-value. The study population was categorized according to features of immune-mediated hepatitis (positive autoantibodies and elevated immunoglobulin G levels) and corticosteroid therapy for the liver injury. We identified 87 patients (63%, female), median age 48 (range: 18-79) years at presentation. Liver injury was diagnosed a median 15 (range: 3-65) days after vaccination. Fifty-one cases (59%) were attributed to the Pfizer-BioNTech (BNT162b2) vaccine, 20 (23%) cases to the Oxford-AstraZeneca (ChAdOX1 nCoV-19) vaccine and 16 (18%) cases to the Moderna (mRNA-1273) vaccine. The liver injury was predominantly hepatocellular (84%) and 57% of patients showed features of immune-mediated hepatitis. Corticosteroids were given to 46 (53%) patients, more often for grade 3-4 liver injury than for grade 1-2 liver injury (88.9% vs. 43.5%, p = 0.001) and more often for patients with than without immune-mediated hepatitis (71.1% vs. 38.2%, p = 0.003). All patients showed resolution of liver injury except for one man (1.1%) who developed liver failure and underwent liver transplantation. Steroid therapy was withdrawn during the observation period in 12 (26%) patients after complete biochemical resolution. None had a relapse during follow-up. CONCLUSIONS: SARS-CoV-2 vaccination can be associated with liver injury. Corticosteroid therapy may be beneficial in those with immune-mediated features or severe hepatitis. Outcome was generally favorable, but vaccine-associated liver injury led to fulminant liver failure in one patient.

Acute autoimmune-like hepatitis with atypical anti-mitochondrial antibody after mRNA COVID-19 vaccination: A novel clinical entity?

Autoimmune phenomena and clinically apparent autoimmune diseases, including autoimmune hepatitis, are increasingly been reported not only after natural infection with the SARS-CoV-2 virus, but also after vaccination against it. We report the case of a 63-year old man without a history of autoimmunity or SARS-CoV-2 natural infection who experienced acute severe autoimmune-like hepatitis seven days after the first dose of the mRNA-1273 SARS-CoV-2 vaccine. Liver histology showed inflammatory portal infiltrate with interface hepatitis, lobular and centrilobular inflammation with centrilobular necrosis, in absence of fibrosis and steatosis. Serum immunoglobulin G was slightly elevated. Autoimmune liver serology showed an indirect immunofluorescence pattern on triple rodent tissue compatible with anti-mitochondrial antibody (AMA), but, unexpectedly, this pattern was not mirrored by positivity for primary biliary cholangitis (PBC)-specific molecular tests, indicating that this antibody is different from classical AMA. Anti-nuclear antibody (ANA) was also positive with a rim-like indirect immunofluorescence pattern on liver and HEp2 cell substrates, similar to PBC-specific ANA; however, anti-gp210 and a large panel of molecular-based assays for nuclear antigens were negative, suggesting a unique ANA in our patient. He carries the HLA DRB1*11:01 allele, which is protective against PBC. Response to prednisone treatment was satisfactory. The clinical significance of these novel specificities needs to be further evaluated in this emerging condition.

Primary biliary cholangitis with normal alkaline phosphatase: A neglected clinical entity challenging current guidelines.

BACKGROUND & AIM: The diagnosis of primary biliary cholangitis (PBC), an uncommon immune-mediated cholestatic liver disease, is based on positive circulating anti-mitochondrial (AMA) and/or PBC-specific anti-nuclear autoantibodies (ANA), coupled with elevated serum alkaline phopsphatase (ALP) levels. Timely initiation of treatment with ursodeoxycholic acid prevents progression to cirrhosis and liver failure. We aimed at investigating liver histology in patients with normal ALP level and positive AMA and/or PBC-specific ANA. METHODS: We searched the Swiss PBC Cohort Study database, which includes subjects with positive PBC autoimmune serology and normal ALP levels, for patients who underwent a liver biopsy. Histological slides were centrally reviewed by an expert liver pathologist, and sera were centrally re-tested for AMA and ANA. RESULTS: 30 patients were included; 90% females, median age 53 (range 27-72) years. Twenty-four (80%) had liver histology typical for (n = 2), consistent with (n = 16) or suggestive of (n = 6) PBC, including three of four AMA-negative ANA-positive patients. Among 22 ursodeoxycholic acid treated patients, 14 had elevated GGT levels before treatment; a significant decrease of the median GGT level between pre- (1.46 x ULN) and post- (0.43 x ULN) treatment (p = 0.0018) was observed. CONCLUSIONS: In our series, a high proportion of AMA positive patients with normal ALP levels have PBC. For the first time we show histological diagnosis of PBC in AMA-negative/PBC-specific ANA-positive subjects and the potential role of GGT as a biomarker in PBC patients with normal baseline ALP levels. Current guidelines for the diagnosis of PBC do not cover the whole extent of PBC presentation, with important clinical implications in terms of timely treatment initiation.

Autoimmune liver serology before and after successful treatment of chronic hepatitis C by direct acting antiviral agents.

BACKGROUND AND AIMS: Chronic hepatitis C virus (HCV) infection is associated with a wide range of immunopathological manifestations, which are significantly improved by successful interferon-based treatment. There is paucity of data on the impact of interferon-free HCV clearance on immunopathological manifestations, which might be expected to disappear more frequently as compared to what reported in interferon-induced HCV-clearance. We have investigated liver autoimmune serology before and after interferon-free clearance of HCV by treatment with direct acting antiviral agents (DAA). METHOD: Patients within the Swiss Hepatitis C Cohort Study who underwent successful (SVR 12) HCV treatment with DAA were tested for autoimmune liver serology according to dedicated guidelines before and at least 6 months after end of treatment. RESULTS: A total of 235 patients were included; 62% males; median age 56 years; 27% with cirrhosis. Median time between end of DAA treatment and post-treatment serum sampling was 17 months. At least one autoantibody before treatment was found in 175 (74%) patients ; 32 (14%) were positive for 2 autoantibodies; no patient was positive for anti-SLA, anti-LC1 or typical AMA before or after DAA. ANA disappeared in 34%, SMA in 52% and anti-LKM1 in one of two patients after successful treatment, but, unexpectedly, one or more autoantibodies appeared in 27% of pre-treatment negative subjects. CONCLUSION: HCV clearance by DAA is associated with autoantibody disappearance in more than one third of the patients who were positive before treatment. However, the majority of the patients remain autoantibody-positive and 27% of those who were negative before treatment developed autoantibodies after DAA-induced HCV clearance. These data confirm that HCV infection is associated with autoimmunity and show that the autoimmune imprint persists after viral clearance by DAA, suggesting that long-term follow-up may be warranted.

The challenges of primary biliary cholangitis: What is new and what needs to be done.

Primary Biliary Cholangitis (PBC) is an uncommon, chronic, cholangiopathy of autoimmune origin and unknown etiology characterized by positive anti-mitochondrial autoantibodies (AMA), female preponderance and progression to cirrhosis if left untreated. The diagnosis is based on AMA- or PBC-specific anti-nuclear antibody (ANA)-positivity in the presence of a cholestatic biochemical profile, histologic confirmation being mandatory only in seronegative cases. First-line treatment is ursodeoxycholic acid (UDCA), which is effective in preventing disease progression in about two thirds of the patients. The only approved second-line treatment is obeticholic acid. This article summarizes the most relevant conclusions of a meeting held in Lugano, Switzerland, from September 23rd-25th 2018, gathering basic and clinical scientists with various background from around the world to discuss the latest advances in PBC research. The meeting was dedicated to Ian Mackay, pioneer in the field of autoimmune liver diseases. The role of liver histology needs to be reconsidered: liver pathology consistent with PBC in AMA-positive individuals without biochemical cholestasis is increasingly reported, raising the question as to whether biochemical cholestasis is a reliable disease marker for both clinical practice and trials. The urgent need for new biomarkers, including more accurate markers of cholestasis, was also widely discussed during the meeting. Moreover, new insights in interactions of bile acids with biliary epithelia in PBC provide solid evidence of a role for impaired epithelial protection against potentially toxic hydrophobic bile acids, raising the fundamental question as to whether this bile acid-induced epithelial damage is the cause or the consequence of the autoimmune attack to the biliary epithelium. Strategies are needed to identify difficult-to-treat patients at an early disease stage, when new therapeutic approaches targeting immunologic pathways, in addition to bile acid-based therapies, may be effective. In conclusion, using interdisciplinary approaches, groundbreaking advances can be expected before long in respect to our understanding of the etiopathogenesis of PBC, with the ultimate aim of improving its treatment.

Autoimmune sclerosing cholangitis: Evidence and open questions.

Juvenile sclerosing cholangitis is a rare chronic hepatobiliary disorder characterized by inflammation of the intra- and/or extrahepatic bile ducts, bile duct dilatation, narrowing and obliteration, and, histologically, by inflammatory bile duct damage leading to periductular fibrosis. The diagnosis is based on endoscopic retrograde cholangiopancreatography or magnetic resonance cholangiopancreatography. In children, it may be associated to a variety of systemic and hepatic conditions: thus, the term "primary" sclerosing cholangitis should be reserved for the rare cases without a known cause. Small duct disease is diagnosed in the presence of histological features diagnostic of sclerosing cholangitis and normal cholangiography. Autoimmune sclerosing cholangitis (ASC) is a form of sclerosing cholangitis with strong autoimmune features overlapping with those of autoimmune hepatitis (AIH). It is a well-recognized nosological entity in paediatrics, where it accounts for the majority of sclerosing cholangitis cases. It is as prevalent as AIH in children, is equally frequent in males and females, half of the patients have concomitant inflammatory bowel disease, virtually all patients have raised immunoglobulin G levels and positive anti-nuclear and/or anti-smooth muscle antibodies. Half of the ASC patients respond well to standard immunosuppressive treatment for AIH with the addition of ursodeoxycholic acid, but the transplant rate is higher than in AIH, and post-transplant recurrence is frequent. A number of open questions remain: are ASC and AIH distinct entities or different manifestations of the same condition? What is the role of histology? Is small duct disease a specific entity? What is the relationship between ASC and adult primary sclerosing cholangitis? What is the role of inflammatory bowel disease? In addition, validated diagnostic criteria for ASC are needed.

The clinical usage and definition of autoantibodies in immune-mediated liver disease: A comprehensive overview.

Autoimmune serology is key to the diagnosis and management of autoimmune liver diseases. Its correct use in clinical practice requires a basic knowledge of the laboratory techniques used for autoantibody detection. Indirect immunofluorescence (IIF) on triple rodent tissue is still the gold standard screening procedure for liver-relevant autoantibodies, while HEp2 cells and human ethanol-fixed neutrophils are used as substrates to characterize nuclear reactivities and to detect anti-neutrophil cytoplasm antibody, respectively. Assays based on purified or recombinant antigens are increasingly used, having the main advantage of being observer-independent and the disadvantage of detecting only autoantibodies whose antigenic target has been identified. The AIH-specific anti-soluble liver antigen antibody cannot be detected by IIF and a molecular-based assay should be used at the screening level. Since autoantibodies may be present in the context of viral hepatitides and other inflammatory liver diseases it is important to exclude these conditions before diagnosing autoimmune liver disease. Anti-nuclear antibody (ANA), most often with a homogeneous IIF pattern on HEp2 cells, characterizes type 1 autoimmune hepatitis (AIH), and is found in association with anti-smooth muscle antibody in about half of the cases. Two IIF ANA patterns are specific for primary biliary cholangitis, namely the rim-like/membranous pattern, and the multiple nuclear dots pattern. Anti-liver kidney microsomal antibody type 1 is the serological hallmark of type 2 AIH, often in association with anti-liver cytosol type 1 antibody. Atypical perinuclear anti-neutrophil antibody, referred to as perinuclear anti-neutrophil nuclear antibody, is frequently detected in primary sclerosing cholangitis, in AIH type 1 and in inflammatory bowel diseases. The anti-asiaglycoprotein receptor antibody is liver-specific but not disease-specific, and reliable commercial assays for its detection are lacking. Anti-mitochondrial antibody is the hallmark of primary biliary cholangitis (PBC), being disease-specific and present in about 95% of the PBC patients. Its incidental detection presages the future development of PBC.

Juvenile autoimmune hepatitis: A comprehensive review.

Autoimmune hepatitis (AIH) is a rare, chronic disease that affects both adults and children, including infants. The disease is probably triggered by environmental factors in genetically predisposed individuals. The clinical presentation ranges from asymptomatic patients or patients with non-specific symptoms, such as fatigue, to fulminant liver failure, many children presenting with symptoms indistinguishable from those of acute hepatitis. Raised transaminase and immunoglobulin G (IgG) levels, in association with circulating autoantibodies, guide towards the diagnosis. The histological hallmark is interface hepatitis, which however is non-specific and may be absent. There are no bile duct changes on cholangiography. Presence of anti-nuclear antibody (ANA) and/or anti-smooth muscle antibody (SMA) is characteristic for type 1 AIH, whereas presence of anti-liver kidney microsomal type 1 (LKM1) antibody and/or anti-liver cytosol type 1 (LC1) antibody defines type 2 AIH. The latter accounts for about one third of the juvenile AIH cases, presents more acutely than type 1 AIH and is very rare in adults. Immunosuppressive therapy, based on steroids and azathioprine, is required, and in the vast majority of patients leads to clinical and biochemical remission, defined as absence of symptoms, normal transaminase and IgG levels, and negative or low-titer autoantibodies. In patients intolerant or non-responder to standard therapy, a number of second line drugs have been employed with variable results. For the rare cases who progress to end-stage liver disease, liver transplantation is life-saving, but recurrence of the disease is possible. A better understanding of the underlying pathogenic mechanisms will help to develop new, more effective and less toxic therapies, and to tailor treatment regimens to the individual patient.

Autoimmune liver disease serology in acute hepatitis E virus infection.

The etiology of autoimmune hepatitis (AIH) is unknown, though hepatotropic viruses may be potential triggers. Hepatitis E virus (HEV) infection, an increasingly recognized cause of acute hepatitis, has been misdiagnosed as AIH due to the occurrence of autoantibodies during its acute phase. It has also been suggested that HEV infection may lead to or unmask AIH. The HEV seroprevalence has been ascertained in patients with AIH, but the prevalence of AIH-related autoantibodies in patients with HEV infection has not been systematically tested. We aimed to investigate whether acute HEV infection is associated with the presence of AIH-relevant autoantibodies, following the liver autoimmune serology guidelines of the International AIH Group. We tested 48 patients with acute HEV infection. Half of them had at least one autoantibody, 17% two autoantibodies. Anti-nuclear antibody (ANA) were detected in 16 (33%), anti-smooth muscle antibody (SMA) in 10 (21%), and anti-neutrophil cytoplasmic antibody (ANCA) in 7 (14.6%). Of note, two patients showed SMA with VG or VGT patterns and five had ANA with homogeneous appearance, both being typical of AIH type 1. Other AIH-specific autoantibodies were negative. Atypical anti-mitochondrial antibody, without evidence of primary biliary cholangitis, was positive in one patient, disappearing at follow-up. Follow-up (median 12 months) serum was available from seven autoantibody positive patients: two became negative, while five remained positive, although no patient developed AIH to date. In conclusion, autoantibodies are frequently present during acute HEV infection, indicating that HEV should always be excluded before diagnosing AIH. Importantly, a minority of patients with acute hepatitis E develops AIH-specific autoantibodies, and, though they did not progress to autoimmune liver disease in the short-term, they warrant long-term monitoring.

Hepatitis E virus as a cause of acute hepatitis acquired in Switzerland.

BACKGROUND: Autochthonous hepatitis E is increasingly recognized as zoonotic infection in western countries. Serological assays have varying sensitivity and specificity. METHODS: We implemented molecular testing to identify and characterize acute hepatitis E acquired in Switzerland. RESULTS: Ninety-three cases of mostly symptomatic acute hepatitis E acquired in Switzerland were documented by PCR between November 2011 and December 2016. Median HEV RNA was 7.5 x 104 IU/mL (range, 5.3 to 4.7 x 107 IU/mL). HEV genotyping was successful in 78 patients, revealing genotype 3 in 75 and genotype 4 in three patients. Phylogenetic analyses revealed a few limited geographical and temporal clusters. Of the 91 patients with available anti-HEV IgM serology, four were negative; three of these were also IgG-negative, likely as a result of immunosuppression, and one was IgG-positive, a constellation compatible with HEV reinfection. Median age of the patients was 58 years (range, 20-80 years); 71 (76.3%) were men and 49 of these (69.0%) were ≥ 50 years old. The clinical course was particularly severe in patients with underlying chronic liver disease, with fatal outcome in two patients. Six patients (6.5%) presented with neuralgic amyotrophy. CONCLUSIONS: Nucleic acid-based diagnosis reveals HEV as a relevant cause of acute hepatitis in Switzerland. Middle-aged and elderly men constitute the majority of symptomatic patients. Testing for HEV should be included early in the diagnostic workup of acute hepatitis and of neuralgic amyotrophy, a typical extrahepatic manifestation of HEV genotype 3 infection.

Direct antiviral agent treatment of chronic hepatitis C results in rapid regression of transient elastography and fibrosis markers fibrosis-4 score and aspartate aminotransferase-platelet ratio index.

BACKGROUND: Novel direct antiviral agents (DAA) targeting hepatitis C virus (HCV) have revolutionized the treatment of chronic hepatitis C infection (CHC). Rates of sustained virological response (SVR) to treatment have drastically improved since introduction of DAA. Transient Elastography (TE) is an ultrasound based, non-invasive technique to assess liver stiffness (LS). We examined the changes in TE values and fibrosis scores FIB-4 and APRI after DAA treatment of CHC. METHODS: 549 patients who received a DAA based treatment for CHC were screened and 392 were included. TE values recorded prior to therapy and within 18 months after therapy were evaluated. In addition, FIB-4 and APRI scores were calculated and histopathological results were recorded if available. RESULTS: Median TE prior to DAA treatment was 12.65 kPa (IQR 9.45-19.2 kPa) and decreased to 8.55 kPa (IQR 5.93-15.25) post-treatment. This finding is statistically significant (P<.001) and equals a TE regression of 32.4% after DAA treatment. Median FIB-4 and APRI values significantly decreased from 2.54 (IQR 1.65-4.43) and 1.10 (IQR 0.65-2.43) to 1.80 (IQR 1.23-2.84, P<.001) and 0.43 (IQR 0.3-0.79, P<.001) respectively. CONCLUSION: Patients with SVR after DAA therapy showed significant regression of TE values. Rapid decrease in TE was in concordance with regression of validated fibrosis scores FIB-4 and APRI. It remains to be examined whether this indicates a true regression of fibrosis or merely resolution of chronic liver inflammation with subsequent improvement of TE values and laboratory parameters.