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Second-line and third-line therapy for autoimmune hepatitis: A position statement from the European Reference Network on Hepatological Diseases and the International Autoimmune Hepatitis Group

  • Ansgar W. Lohse
    Correspondence
    Corresponding author. Address: I. Department of Medicine, University Medical Centre Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg. Tel.: +40 40 7410 53910; Fax: +40 40 7410 58531.
    Affiliations
    I. Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Marcial Sebode
    Affiliations
    I. Department of Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Marianne H. Jørgensen
    Affiliations
    Department of Paediatrics and Adolescent Medicine, Rigshospitalet, Copenhagen, Denmark

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Henriette Ytting
    Affiliations
    Departments of Medical Gastroenterology and Hepatology, Hvidovre University Hospital and Rigshospitalet, Copenhagen, Denmark

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Tom H. Karlsen
    Affiliations
    Norwegian PSC Research Centre, Department of Transplantation Medicine, Division of Surgery, Inflammatory Diseases and Transplantation, Oslo University Hospital Rikshospitalet, Oslo, Norway

    Institute of Clinical Medicine, University of Oslo, Oslo, Norway

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Deirdre Kelly
    Affiliations
    Liver Unit, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, West Midlands, UK

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Michael P. Manns
    Affiliations
    Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • Mette Vesterhus
    Affiliations
    Department of Clinical Science, University of Bergen, Bergen, Norway

    Norwegian PSC Research Centre, Department of Transplantation Medicine, Division of Surgery, Inflammatory Diseases and Transplantation, Oslo University Hospital Rikshospitalet, Oslo, Norway

    European Reference Network on Hepatological Diseases (ERN RARE-LIVER)
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  • on behalf of theEuropean Reference Network on Hepatological Diseases (ERN RARE-LIVER)
  • Affiliations
    IAIHG steering committee (Joost P. H. Drenth, Michael Heneghan, Nanda Kerkar, Ansgar W. Lohse, Aldo J. Montano-Loza and Diego Vergani), and secretaries (Ynto S. de Boer and Rodrigo Liberal)

      Summary

      Most patients with autoimmune hepatitis respond well to standard immunosuppressive therapy with steroids and azathioprine, and while untreated disease is usually fatal, patients who respond well to therapy have an excellent prognosis. However, insufficient response to standard therapy or intolerable side effects requiring dose adaptions or treatment changes occur in 10–20% of patients. While there is fairly good agreement on second-line treatment options, there is very wide variation in the indication and use of possible third-line therapies. Herein, the European Reference Network on Hepatological Diseases (ERN RARE-LIVER) and the International Autoimmune Hepatitis Group (IAIHG) outline a treatment algorithm for both children and adults that should help to standardise treatment approaches, in order to improve patient care and to enable the comparison of treatment results between scientific publications.

      Graphical abstract

      Keywords

      Linked Article

      Introduction

      Response to initial corticosteroid therapy is so nearly universal in autoimmune hepatitis (AIH) that it is considered a diagnostic criterion.
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      There is consensus that azathioprine should be added within 2 weeks of starting steroids, if total bilirubin levels are <6 mg/dl, and that azathioprine should be the backbone of any maintenance therapy.
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      The exact titration of doses during maintenance therapy, and the decision on whether to use higher doses of azathioprine as a possible monotherapy or low-dose prednisone (e.g. 5 mg/day) combined with low dose azathioprine (around 1 mg/kg body weight) depend on individual risk factors and preferences, and should be decided together with the patient. There is also consensus that relapse rates after withdrawal of therapy are extremely high, and withdrawal should only be attempted in patients who have been in stable remission on low-dose therapy for at least 2 years.
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      Relapse is almost universal after withdrawal of immunosuppressive medication in patients with autoimmune hepatitis in remission.
      Liver biopsy before treatment withdrawal has been recommended by many guidelines on AIH, but is considered optional in the EASL Clinical Practice Guideline. Due to the limitations of liver biopsy with respect to sampling errors, and due to the increasing evidence for biochemical remission as a reliable predictive marker, liver biopsy has become less important in the assessment of remission. Patients with alanine aminotransferase (ALT) levels below half the upper limit of normal in combination with IgG levels below 12 g/L have a very good chance of successful treatment withdrawal
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      and therefore probably do not need liver biopsy before weaning of immunosuppression. The main role of liver biopsy on follow-up is to distinguish remaining AIH activity from other causes of elevated liver enzymes (drug toxicity, associated non-alcoholic steatohepatitis [NASH] etc.), and to adapt management accordingly. Furthermore, whenever there is doubt that biochemical parameters are reliable in the assessment of remission, e.g. if IgG levels were not elevated at the beginning of treatment, or if levels of transaminases are close to the upper limit of normal, liver biopsy may also provide valuable information for patient management. Treatment withdrawal should be avoided during puberty, irrespective of the duration of remission, and it should only be considered with great caution in patients with type 2 AIH and all patients in whom the disease first manifested in childhood.
      There is wide consensus that remission can be defined both biochemically and histologically.
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      • Baggenstoss A.H.
      Laboratory assessment of severe chronic active liver disease during and after corticosteroid therapy: correlation of serum transaminase and gamma globulin levels with histologic features.
      Biochemical remission is defined as normal transaminases and normal IgG levels.
      European Association for the Study of the Liver
      EASL Clinical Practice Guidelines: autoimmune hepatitis.
      ,
      • Mack C.L.
      • Adams D.
      • Assis D.N.
      • Kerkar N.
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      • Mayo M.J.
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      In the paediatric literature, the decrease or even disappearance of autoantibodies is also considered an important marker of remission.
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      However, this may be very closely linked to IgG levels, and has thus far not been confirmed as an independent indicator of remission. Histological remission is defined as a hepatitis activity index (HAI-score) of up to 3 out of 18, as this degree of disease activity is widely regarded as non-progressive.
      European Association for the Study of the Liver
      EASL Clinical Practice Guidelines: autoimmune hepatitis.
      ,
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      Histological grading and staging of chronic hepatitis.
      A recent case series has demonstrated that patients reaching full biochemical remission not only do not progress, but even show regression of liver fibrosis, as measured by repeated evaluation of transient elastography, e.g. by Fibroscan.
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      Usefulness of biochemical remission and transient elastography in monitoring disease course in autoimmune hepatitis.
      On the other hand, this study (and others) have confirmed that remaining disease activity is associated with progressive fibrosis and development of cirrhosis, thus underlining the need to achieve full biochemical remission if possible.
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      • et al.
      Persistent elevation of serum alanine aminotransferase levels leads to poor survival and hepatocellular carcinoma development in type 1 autoimmune hepatitis.
      • Verma S.
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      • Mendler M.
      • Govindrajan S.
      • Redeker A.
      Factors predicting relapse and poor outcome in type I autoimmune hepatitis: role of cirrhosis development, patterns of transaminases during remission and plasma cell activity in the liver biopsy.
      • Muratori L.
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      • Ferri S.
      • Lenzi M.
      Application of the 2010 American Association for the study of liver diseases criteria of remission to a cohort of Italian patients with autoimmune hepatitis.
      • Montano-Loza A.J.
      • Carpenter H.A.
      • Czaja A.J.
      Improving the end point of corticosteroid therapy in type 1 autoimmune hepatitis to reduce the frequency of relapse.
      ,
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      • Krech T.
      • Zenouzi R.
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      Usefulness of biochemical remission and transient elastography in monitoring disease course in autoimmune hepatitis.
      Patients with AIH require alternatives to standard immunosuppressive treatment in two clinical scenarios: insufficient response, i.e. not achieving remission, or intolerance due to side effects.
      While there is growing consensus on the standard management of autoimmune hepatitis, there is a considerable degree of uncertainty regarding how to deal with patients insufficiently responding to standard therapy, or not tolerating standard therapy. The EASL clinical practice guideline and the ESPGHAN position statement recommend mycophenolate mofetil (MMF) for those patients not tolerating azathioprine, and this also appears to be a widely held consensus beyond Europe.
      European Association for the Study of the Liver
      EASL Clinical Practice Guidelines: autoimmune hepatitis.
      ,
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      • Mayo M.J.
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      While the data for MMF in patients intolerant to azathioprine are encouraging, MMF seems of little benefit in those patients not responding sufficiently to first-line therapy, but there are only limited data on this issue.
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      A single center review of the use of mycophenolate mofetil in the treatment of autoimmune hepatitis.
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      Tacrolimus and mycophenolate mofetil as second-line therapies for pediatric patients with autoimmune hepatitis.
      The largest controlled trial in autoimmune hepatitis addressed the role of budesonide as an alternative steroid to prednisone in induction therapy.
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      Budesonide induces remission more effectively than prednisone in a controlled trial of patients with autoimmune hepatitis.
      Besides establishing budesonide as an alternative drug that can induce remission with less steroid-specific side effects, this trial demonstrated the very high rate of patients not achieving biochemical remission within 6 months (using normal ALT as an endpoint). While some authors have criticised this trial for applying a rather low dose of prednisone and for tapering prednisone too strictly and too quickly in some patients, overall the treatment reflected widely used standards, and yet in both treatment arms more than 30% of patients were not in biochemical remission at month 6. Together with epidemiological studies showing increased liver-related mortality in AIH despite therapy, this trial highlights that there is still an unmet need for more effective and better tolerated therapeutic options in AIH.
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      Therefore, in addition to the need for new drugs and new therapeutic approaches, we need recommendations, and in due course better data, on how to deal with patients who are not responding sufficiently or are intolerant to standard therapy in AIH.
      The scarcity of data, with only small studies and case series published so far (Table S1), and the wide variation of inclusion criteria and drug usage, do not currently allow for recommendations regarding which particular third-line therapy should be used in an individual patient. Multicentre studies are needed to accumulate data with sufficient power to make robust conclusions. In order to achieve this most efficiently, we need to structure, standardise and report our approach to patients with AIH in need of third-line therapy. The following position statement is the result of repeated discussions within the scientific community coordinated by the European Reference Network on Hepatological Diseases (ERN RARE-LIVER) and the International Autoimmune Hepatitis Group (IAIHG); it was developed in order to help in the management of these patients, and in order to agree on a standard process, in particular for the use of third-line therapies, that enables the collection of comparable data from treatment centres. It is hoped that, based on this treatment algorithm, such data can be collected in the future, helping us to improve management of this important patient population, with the final goal of establishing third-line treatment options based on high-quality data in adequately powered studies. This position statement will cover both adult and paediatric data and address the two key problems, sometimes intertwined: insufficient response and intolerance (Fig. 1 and 2).
      Figure thumbnail gr1
      Fig. 1Treatment algorithm for patients with an insufficient response to first-line treatment.
      In patients with AIH and an insufficient response under first-line treatment with steroids and azathioprine, the active metabolite of azathioprine, 6-TGN, should be measured. Insufficient response in patients with AIH is defined by not achieving full remission. Biochemical remission is defined as normal transaminases as well as normal IgG levels and histological remission is defined as a HAI-score of up to 3 out of 18. Patients with 6-TGN levels below 220 pmol per 8 × 108 red blood cells should be assessed for non-compliance. After exclusion of non-compliance, optimisation of 6-TGN levels, either by increasing azathioprine dosage or by the combination of low-dose azathioprine and allopurinol, should be performed. In patients with AIH not achieving full response and with 6-TGN levels above 220 pmol per 8 × 108 red blood cells, alternative or concomitant diagnoses to AIH must be considered before steroid and azathioprine treatment is intensified or third-line treatment is started. 6-TGN, 6-thioguanine nucleotide; AIH, autoimmune hepatitis; HAI, hepatitis activity index.
      Figure thumbnail gr2
      Fig. 2Treatment algorithm for patients with side-effects under first-line treatment.
      Patients with AIH who are intolerant to standard treatment with azathioprine due to side effects, should be treated with 6-mercaptopurine or mycophenolate mofetil before starting third-line treatment. Insufficient response in patients with AIH is defined by not achieving full remission. Biochemical remission is defined as normal transaminases as well as normal IgG levels and histological remission is defined as a hepatitis activity index score of up to 3 out of 18.

      Insufficient response

      The treatment aim in every patient with autoimmune hepatitis is prevention of progressive liver disease. Lack of progression, and even regression of fibrosis, is observed in more or less all patients with full biochemical remission, defined as normal transaminases and normal IgG levels.
      • Miyake Y.
      • Iwasaki Y.
      • Terada R.
      • Okamaoto R.
      • Ikeda H.
      • Makino Y.
      • et al.
      Persistent elevation of serum alanine aminotransferase levels leads to poor survival and hepatocellular carcinoma development in type 1 autoimmune hepatitis.
      • Verma S.
      • Gunuwan B.
      • Mendler M.
      • Govindrajan S.
      • Redeker A.
      Factors predicting relapse and poor outcome in type I autoimmune hepatitis: role of cirrhosis development, patterns of transaminases during remission and plasma cell activity in the liver biopsy.
      • Muratori L.
      • Muratori P.
      • Lanzoni G.
      • Ferri S.
      • Lenzi M.
      Application of the 2010 American Association for the study of liver diseases criteria of remission to a cohort of Italian patients with autoimmune hepatitis.
      • Montano-Loza A.J.
      • Carpenter H.A.
      • Czaja A.J.
      Improving the end point of corticosteroid therapy in type 1 autoimmune hepatitis to reduce the frequency of relapse.
      ,
      • Hartl J.
      • Ehlken H.
      • Sebode M.
      • Peiseler M.
      • Krech T.
      • Zenouzi R.
      • et al.
      Usefulness of biochemical remission and transient elastography in monitoring disease course in autoimmune hepatitis.
      It is uncertain whether histological proof of remission by demonstration of no or only minimal inflammatory activity (HAI <3/18) on liver biopsy is more reliable than biochemical remission. On the one hand, histology is considered the gold standard; on the other hand, due to the risk of sampling error with biopsy, biochemical remission parameters might provide a better overall picture. The two approaches can be considered complementary. For example, in patients with borderline biochemical parameters, a liver biopsy may help to assess the remaining disease activity more reliably. Furthermore, liver biopsy may be able to detect possible azathioprine hepatotoxicity or comorbidities, such as NASH, responsible for continued abnormal transaminase levels.
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      • Wilcox R.
      Natural history of patients presenting with autoimmune hepatitis and coincident nonalcoholic fatty liver disease.
      When full biochemical remission is achieved, histological confirmation of remission is not required. Similarly, if both IgG and transaminases show a clearly insufficient response, histological confirmation of insufficient response is also not required. For all other cases, histological
      Biochemical remission of AIH is defined as normal transaminases as well as normal IgG levels and histological remission is defined as a hepatitis activity index (HAI-score) of up to 3 out of 18.
      diagnosis is recommended, as the resulting treatment decisions may have important consequences, and are likely to determine the long-term treatment of this chronic disease.
      While insufficient response in the initial treatment period is not well defined, and needs to be assessed individually depending on the severity of disease and comorbidities, we have agreed that insufficient response is failure to achieve full biochemical remission within the first 6 months of treatment.
      • Czaja A.J.
      Rapidity of treatment response and outcome in type 1 autoimmune hepatitis.
      While in many patients full biochemical remission can be achieved even faster than that, 6 months seems a reasonable time to wait, as some patients respond slower than others.
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      • Vrolijk J.M.
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      • Bouma G.
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      Rapid response to treatment of autoimmune hepatitis associated with remission at 6 and 12 months.
      In some patients with initially severe disease and a clear tendency toward improvement, achieving full biochemical remission may even take a few months longer than 6 months, but for the vast majority of patients the 6-month time point is appropriate for assessing response and should therefore be standard. Histological remission does take longer than biochemical remission, and thus histological evaluation for degree of response may need to be delayed for a further 6 months (up to 1 year) if there is uncertainty in the interpretation of biochemical response
      • Soloway R.D.
      • Summerskill W.H.
      • Baggenstoss A.H.
      • Geall M.G.
      • Gitnićk G.L.
      • Elveback I.R.
      • et al.
      Clinical, biochemical, and histological remission of severe chronic active liver disease: a controlled study of treatments and early prognosis.
      – this can be the case if values for transaminases or IgG are borderline, or if there is a discrepancy between transaminase response and IgG response.
      We recommend measuring drug levels of azathioprine metabolites in patients with insufficient response (Fig. 1).
      European Association for the Study of the Liver
      EASL Clinical Practice Guidelines: autoimmune hepatitis.
      ,
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      Characterisation and utility of thiopurine methyltransferase and thiopurine metabolite measurements in autoimmune hepatitis.
      ,
      • Rumbo C.
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      • Shneider B.L.
      Azathioprine metabolite measurements in the treatment of autoimmune hepatitis in pediatric patients: a preliminary report.
      There are two main reasons for this recommendation:
      • Azathioprine drug metabolism varies widely between individuals. It is the group of 6-thioguanine nucleotides (6-TGN) that contain the main active drug 6-tioguanine-triphosphate (6-TGTP), while the 6-methyl-mercaptopurine metabolites (6-MMP) are not immunosuppressive, but can reflect drug toxicity.
      • Non-adherence to recommended treatment is another important reason for insufficient treatment response and can be detected by absent or very low levels of all drug metabolites.
      Unfortunately, 6-TGN measurements are not trivial and can only be undertaken in a few specialised laboratories. Future studies will need to show the reliability and reproducibility of measurements across different laboratories, but data from transplant immunology as well as from inflammatory bowel disease have shown the value of these measurements in patient management.
      • Bergan S.
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      • Stokke O.
      Monitoring of azathioprine treatment by determination of 6-thioguanine nucleotide concentrations in erythrocytes.
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      Pharmacogenomics and metabolite measurement for 6-mercaptopurine therapy in inflammatory bowel disease.
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      Measurement of thiopurine methyltransferase activity and azathioprine metabolites in patients with inflammatory bowel disease.
      A larger, albeit retrospective study of patients with AIH from Sheffield, UK, showed that patients with 6-TGN levels below 220 pmol/8 × 108 red blood cells were more likely to experience relapse or have insufficiently suppressed disease activity.
      • Dhaliwal H.K.
      • Anderson R.
      • Thornhill E.L.
      • Schneider S.
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      • Gleeson D.
      • et al.
      Clinical significance of azathioprine metabolites for the maintenance of remission in autoimmune hepatitis.
      Therefore, it appears reasonable to try to achieve such a level in all patients with insufficient response and lower levels on drug measurement. This can normally be achieved by addressing adherence to therapy and adapting the dose up to 2 mg or even 2.5 mg/kg body weight, as is customary in treatment of patients with inflammatory bowel disease.
      For those patients with suboptimal levels of 6-TGN and high levels of 6-MMP, the alternative drug metabolite, the underlying problem is altered drug metabolism in the presence of good patient adherence. In these patients, again a lesson learned in inflammatory bowel disease, the combination of azathioprine with allopurinol can be very effective, as allopurinol blocks the 6-MMP pathway.
      • Sparrow M.P.
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      • Friedman S.
      • Lim W.C.
      • Reddy S.I.
      • Cao D.
      • et al.
      Allopurinol safely and effectively optimizes tioguanine metabolites in inflammatory bowel disease patients not responding to azathioprine and mercaptopurine.
      ,
      • Sparrow M.P.
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      • Cao D.
      • Hanauer S.B.
      Effect of allopurinol on clinical outcomes in inflammatory bowel disease nonresponders to azathioprine or 6-mercaptopurine.
      This approach involves reducing the dose of azathioprine to about one-fourth of the previous dose and adding 100 mg allopurinol per day to the therapy, in order to achieve similar 6-TGN levels.
      • de Boer Y.S.
      • van Gerven N.M.
      • de Boer N.K.
      • Mulder C.J.
      • Bouma G.
      • van Nieuwkerk C.M.
      Allopurinol safely and effectively optimises thiopurine metabolites in patients with autoimmune hepatitis.
      Allopurinol dosing for this indication is not standardised, as it is normally only used for chemotherapy-induced hyperuricaemia in paediatrics with very high doses up to 10 mg/kg body weight.
      • Krakoff I.H.
      • Murphy M.L.
      Hyperuricemia in neoplastic disease in children: prevention with allopurinol, a xanthine oxidase inhibitor.
      The dose required for the desired drug interaction is closer to 2–3 mg/kg body weight, thus allowing a very good safety margin. In order to achieve therapeutic levels, azathioprine then needs to be carefully increased keeping the allopurinol dosage constant, and drug levels need to be monitored along the way.
      In countries in which 6-TGN measurements are unavailable, some colleagues have used mean corpuscular erythrocyte volume (MCV) as a surrogate marker for azathioprine dosage, as MCV should increase during sufficiently dosed azathioprine.
      • Armstrong L.
      • Sharif J.A.
      • Galloway P.
      • McGrogan P.
      • Bishop J.
      • Russell R.K.
      Evaluating the use of metabolite measurement in children receiving treatment with a thiopurine.
      ,
      • Bouguen G.
      • Sninsky C.
      • Tang K.L.
      • Colombel J.F.
      • DʼHaens G.
      • Kornbluth A.
      • et al.
      Change in erythrocyte mean corpuscular volume during combination therapy with azathioprine and infliximab is associated with mucosal healing: a post hoc analysis from SONIC.
      That said, this approach has not been validated systematically and can only be regarded as a simplistic alternative when drug level testing is not available. However, normal MCV levels in azathioprine-treated patients should, once other causes of microcytosis such as iron deficiency or thalassaemia have been excluded, always raise suspicion of below target drug levels, be they due to non-adherence or to altered drug metabolism.
      In addition to optimising azathioprine dosing, patients with insufficient response should be re-evaluated diagnostically (Fig. 1). This entails questioning the initial diagnosis (Is this really AIH?) as well as excluding alternative and additional diagnoses. Primary sclerosing cholangitis (PSC) as well as primary biliary cholangitis (PBC) should be excluded in any patient with persisting cholestatic features. For possible PBC, tests should be done not only for antimitochondrial autoantibodies (AMA), but also for the PBC-associated antinuclear autoantibodies (ANA), anti-SP100 and anti-gp210, all of which can be tested by highly reliable immunoserological tests.
      European Association for the Study of the Liver
      EASL Clinical Practice Guidelines: autoimmune hepatitis.
      ,
      • Schulz L.
      • Sebode M.
      • Weidemann S.A.
      • Lohse A.W.
      Variant syndromes of primary biliary cholangitis.
      Drug-induced liver injury is another important differential diagnosis to consider, including the possibility of azathioprine-induced liver toxicity. However, the diagnosis of azathioprine hepatotoxicity is often given to patients only based on raised liver enzymes during therapy, and may be a misinterpretation of insufficient response, leading to an unnecessary change to second-line therapy.
      For AIH patients not achieving remission under standard treatment, optimisation of azathioprine dosage on the basis of 6-TGN levels should be aimed at first, before starting alternative immunosuppressants.
      In view of the excellent treatment efficacy of azathioprine in most patients, drug toxicity should not be simply assumed, but needs to be proven, either by liver biopsy, or by drug withdrawal associated with improvement, and re-exposure associated with worsening of liver tests. Histological features of azathioprine drug toxicity are usually quite characteristic and, at least by an experienced liver pathologist, can be well differentiated from AIH activity.
      • Siramolpiwat S.
      • Sakonlaya D.
      Clinical and histologic features of azathioprine-induced hepatotoxicity.
      ,
      • Björnsson E.S.
      • Gu J.
      • Kleiner D.E.
      • Chalasani N.
      • Hayashi P.H.
      • Hoofnagle J.H.
      DILIN Investigators
      Azathioprine and 6-mercaptopurine-induced liver injury: clinical features and outcomes.
      If in doubt, liver biopsy should be sent to a reference centre for re-evaluation. Furthermore, viral infections, in particular Epstein-Barr virus and cytomegalovirus infection in previously seronegative patients, must also be excluded as reasons for raised liver enzymes in patients being treated for AIH.
      Non-alcoholic fatty liver disease (NAFLD) and NASH are frequent diseases in the general population, but they may be even more frequent in AIH as a side-effect of initial steroid therapy. Thus, NAFLD may develop in a patient in whom initial liver biopsy did not show any suspicious features, and should be considered in insufficient responders, especially if the liver test pattern is compatible, usually normal alkaline phosphatase (ALP), high gamma-glutamyltransferase (GGT) and ALT higher than aspartate aminotransferase (AST).
      • De Luca-Johnson J.
      • Wangensteen K.J.
      • Hanson J.
      • Krawitt E.
      • Wilcox R.
      Natural history of patients presenting with autoimmune hepatitis and coincident nonalcoholic fatty liver disease.
      Ultrasound screening showing increased echogenicity of the liver parenchyma, as well as high values of ‘controlled attenuation parameter’ (CAP) on Fibroscan can help in the diagnosis – and again liver biopsy may be required to make the final diagnosis and to try to differentiate the relative role of NAFLD/NASH and AIH activity in explaining the laboratory values.
      Relapse during maintenance therapy may also be considered a version of insufficient response but should be viewed slightly differently depending on the reasons for relapse. The most common form of relapse is due to lowering of maintenance therapy down to a level lower than required in the individual patient. Dose adaption and perhaps a transiently higher steroid dose, depending on the degree of relapse, will solve the problem in the majority of patients, who can then be managed on acceptable levels of standard maintenance therapy. Relapse may also be due to non-adherence; this problem is particularly common in adolescents and young adults but can occur in any age group. Patient preferences and the risks and benefits of therapy should be discussed in these patients; psychological help is sometimes necessary. Repeated relapses despite adequate maintenance therapy and adherence also represent insufficient response.
      In patients with insufficient response, in whom alternative and additional liver disease has been excluded, standard drug therapy should be intensified taking into consideration disease activity, comorbidities, and drug-related side effects (Fig. 1). Third-line therapy should be attempted in patients who are adherent to therapy, and in whom the disease is active and presumably progressive despite intensified therapy; in such cases, third-line therapy should be attempted according to one of the protocols given in Table 1. In non-adherent patients, psychological support and interventions to improve adherence are to be preferred, which may or may not also include third-line therapy. As an alternative to starting third-line therapy directly after unsuccessful intensification of first-line treatment, mycophenolate mofetil (MMF) can be considered as a second-line drug, although its effectiveness in poor responders to first-line therapy seems to be limited.
      • Hennes E.M.
      • Oo Y.H.
      • Schramm C.
      • Denzer U.
      • Buggisch P.
      • Wiegard C.
      • et al.
      Mycophenolate mofetil as second line therapy in autoimmune hepatitis?.
      Fibroscan can be very helpful in assessing disease progression: Fibroscan measures the combination effect of inflammatory infiltration in the liver and fibrosis, and should thus improve upon remission induction.
      • Hartl J.
      • Denzer U.
      • Ehlken H.
      • Zenouzi R.
      • Peiseler M.
      • Sebode M.
      • et al.
      Transient elastography in autoimmune hepatitis: timing determines the impact of inflammation and fibrosis.
      Worsening of Fibroscan during follow-up, especially beyond the first 6 months of therapy, indicates either re-activation of disease, or fibrosis progression, possibly even both.
      • Hartl J.
      • Ehlken H.
      • Sebode M.
      • Peiseler M.
      • Krech T.
      • Zenouzi R.
      • et al.
      Usefulness of biochemical remission and transient elastography in monitoring disease course in autoimmune hepatitis.
      The reasons for starting third-line therapy should be recorded, its pros and cons discussed with the patient, and the results of this discussion recorded. A liver biopsy before the start of third-line treatment is recommended in order to prove the necessity of third-line therapy, to exclude alternative diagnoses, and to have detailed information on disease activity (grading) and fibrosis (staging) prior to starting these experimental therapies. Patient (and in children also parents') preferences need to be taken into consideration when deciding on third-line therapy, both on initiation and on the drugs chosen. The recommendations for patients with insufficient response are summarised in Fig. 1.
      Table 1Third-line therapy in autoimmune hepatitis: Expert opinion and suggestions for standards.
      TherapyDose - AdultsDose - ChildrenComments
      Tacrolimus0.1 mg/kg twice daily, or prolonged-release formulation of tacrolimus in lower dose.

      Serum trough levels <8 ng/ml
      0.05 mg/kg/day.

      Initial serum trough levels 6–8 ng/ml, tapering to 3–5 ng/ml after full biochemical remission has been achieved.
      The best studied alternative. Variable and generally lower doses have been applied in retrospective and prospective studies (e.g. 0.5–6 mg/day or 2–3 mg twice daily). Several of these studies have reported a significant, but insufficient effect (full remission was not achieved). Hence, by expert opinion, we recommend standardisation of the dose at a higher serum trough level as given in this table and tapering the trough levels after remission has been achieved.

      Renal function (eGFR) should be assessed prior to and during treatment; consider dose reduction in cases of eGFR reduction >25%.
      Ciclosporin2 mg/kg twice daily;

      Serum trough levels <120 ng/ml
      4 mg/kg twice daily to initial trough levels at 200–250 ng/ml, tapering to trough levels <120 ng/ml after full biochemical remission has been achieved.Doses of 2–5 mg/kg/day were assessed in a small open-label clinical trial. A dose of 2.5 mg/kg twice daily is frequently advised for non-transplant indications (e.g. nephrotic syndrome) and tapering the trough levels after remission has been achieved.

      Renal function (eGFR) should be assessed prior to and during treatment; consider dose reduction in cases of eGFR reduction >25%.
      Infliximab5 mg/kg/day; at week 0, 2, 6, and every 4–8 weeks thereafterNo dataThe proposed dose corresponds to standard recommendations for other indications (e.g. inflammatory bowel disease, ankylosing arthritis). Maintenance therapy in AIH appears to usually require a 4-week interval contrary to most IBD patients
      Rituximab1,000 mg at week 0 and 2, to be repeated whenever transaminases rise (e.g. after 6–12 months)375 mg/m2Surveillance of CD20+ B-cells is recommended. Supplement with immunoglobulins may be necessary. Paediatric data limited to single case reports.
      Methotrexate7.5–15 mg per week10 mg/m2 per weekData are scarce and limited to case series.

      Some case reports associate development of autoimmune hepatitis with ongoing methotrexate therapy for other indications.
      Cyclophosphamide1–1.5 mg/kg/day or pulse therapy 1 g i.v. every 4 weeksNo dataData are scarce and limited to case series.
      Everolimus0.75–1.5 mg/day

      Serum trough level 3–6 ng/ml
      No dataData are scarce and limited to case series.
      eGFR, estimated glomerular filtration rate; IBD, inflammatory bowel disease.

      Intolerance

      Drug intolerance precludes the use of azathioprine in a fair proportion of patients, estimated to be between 3% and 5%. Reliable prospective studies of the true incidence of azathioprine intolerance are missing. It is an idiosyncratic reaction usually manifesting within the first 2 weeks of therapy, and clinically characterised by general malaise and nausea, often associated with any of the following symptoms: fever, diarrhoea, muscle and body pain, vomiting. Symptoms may mimic acute gastroenteritis, which is a differential diagnosis. Symptoms typically subside within 2 to 3 days of stopping treatment and resume rather more quickly upon re-exposure. Many colleagues will attempt a trial of re-exposure to be certain that it really is azathioprine intolerance, and the first recommendation is to undertake such an attempt by switching from azathioprine to 6-mercaptopurine (6-MP; Fig. 2), thus limiting possible intolerance to 6-MP and its metabolites and avoiding the pre-drug azathioprine. 6-MP is the first metabolite of azathioprine on the way to its active agent 6-TGN.
      • Chan G.L.
      • Erdmann G.R.
      • Gruber S.A.
      • Matas A.J.
      • Canafax D.M.
      Azathioprine metabolism: pharmacokinetics of 6-mercaptopurine, 6-thiouric acid and 6- thioguanine nucleotides in renal transplant patients.
      6-MP is thus just as effective a drug as azathioprine, and in some countries the first drug of choice in this drug class of purine analogues. As only azathioprine, and not 6-MP, is licensed for use as an immunosuppressive agent in most countries, and as azathioprine tablets are available in a wider variety of doses in most countries, most physicians prefer azathioprine, but from a pharmacological point of view, 6-MP is just as effective. The problem of inadequate dosing alternatives may also sometimes hamper optimal therapy in very young children, as azathioprine fluid, which allows exact dosing, is not available everywhere. At the same time steroid maintenance therapy can be problematic in young children due to its negative growth effects, hence some specialists choose MMF as an alternative first-line therapy due to its wider availability in liquid form, allowing individual dosing. Systematic data are lacking, and drug preference should be individualised depending on the steroid dose required and possible side effects of MMF.
      6-mercaptopurine or mycophenolate mofetil are the treatment of choice for AIH patients who are intolerant to standard treatment.
      More data are required to allow for general recommendations. Furthermore, as children develop, a change to standard therapy should be considered.
      Up to 50–75% of patients intolerant to azathioprine are not intolerant to 6-MP, or their side-effects are markedly weaker.
      • Hübener S.
      • Oo Y.H.
      • Than N.N.
      • Hübener P.
      • Weiler-Normann C.
      • Lohse A.W.
      • et al.
      Efficacy of 6-mercaptopurine as second-line treatment for patients with autoimmune hepatitis and azathioprine intolerance.
      It therefore appears prudent to attempt a challenge with 6-MP in a patient suspected of being intolerant to azathioprine (Fig. 2); patients with only milder, mainly gastrointestinal symptoms due to azathioprine are particularly likely to tolerate 6-MP therapy. If symptoms of intolerance recur, this drug class should probably be avoided completely, even though there are some reports of better tolerance with thioguanine, an alternative agent from this drug class.
      • van den Brand F.F.
      • van Nieuwkerk C.M.J.
      • Verwer B.J.
      • de Boer Y.S.
      • de Boer N.K.H.
      • Mulder C.J.J.
      • et al.
      Biochemical efficacy of tioguanine in autoimmune hepatitis: a retrospective review of practice in The Netherlands.
      If 6-MP is tolerated, it should be used, and its dose adapted based on optimal 6-TGN blood levels (starting usually at a dose of mercaptopurine of 0.5–1 mg/kg body weight).
      In patients intolerant to both azathioprine and 6-MP, MMF should be used as a second-line drug, starting at a dose of 500 mg twice daily and increasing to 1 g twice daily; in children, MMF should be started at a dose of 5 mg/kg body weight twice daily up to a maximum of 20 mg/kg body weight twice daily (Fig. 2). MMF seems to be generally better tolerated than azathioprine, but does cause gastrointestinal symptoms in a fair proportion of patients, as well as impaired wound healing, increasing the risk of organ perforation, for example, in peptic ulcer disease. Furthermore, MMF is strictly contraindicated in pregnancy, and for men reliable contraception is recommended because the risk of genotoxicity cannot be completely ruled out.
      • Coscia L.A.
      • Armenti D.P.
      • King R.W.
      • Sifontis N.M.
      • Constantinescu S.
      • Moritz M.J.
      Update on the teratogenicity of maternal mycophenolate mofetil.
      ,
      Mycophenolate: updated recommendations for contraception for men and women. EMA/828208/2017.
      Long-term family planning needs to be discussed with every patient at reproductive age before switching to MMF. This way treatment changes can be avoided if family planning becomes relevant after starting MMF. This is particularly relevant in adolescents and young adults, who may have been put on MMF at some stage, and in whom planned or unplanned pregnancies may lead to a complicated situation. The effectiveness for AIH appears to be good, and it has been reported that up to two-thirds of patients intolerant to azathioprine achieve full biochemical remission using an MMF regimen.
      • Santiago P.
      • Schwartz I.
      • Tamariz L.
      • Levy C.
      Systematic review with meta-analysis: mycophenolate mofetil as a second-line therapy for autoimmune hepatitis.
      • De Lemos-Bonotto M.
      • Valle-Tovo C.
      • Costabeber A.M.
      • Mattos A.A.
      • Azeredo-da-Silva A.L.F.
      A systematic review and meta-analysis of second-line immunosuppressants for autoimmune hepatitis treatment.
      • Giannakopoulos G.
      • Verbaan H.
      • Friis-Liby I.L.
      • Sangfelt P.
      • Nyhlin N.
      • Almer S.
      Swedish Hepatology study group, SweHep
      Mycophenolate mofetil treatment in patients with autoimmune hepatitis failing standard therapy with prednisolone and azathioprine.
      This approach is summarised in Fig. 2.
      In paediatrics and adolescents, growth development, problems with adherence and availability of liquid formulations of immunosuppressive drugs for small children can be additional reasons to adapt the treatment strategy.
      Side effects of corticosteroids may also be severe and be considered to cause intolerance in some patients. During adolescence, non-adherence to steroid-based therapy may be a major problem, both due to real as well as to perceived or feared potential side effects. As high-dose steroids are usually only required for short periods, dose adaptation should first be tried in this situation, preferably by optimising azathioprine treatment as rapidly as possible in order to spare steroids. Budesonide can be considered as an alternative in patients with severe steroid side effects, but is contraindicated in all patients with cirrhosis, in whom the first-pass effect is impaired, increasing the risk of steroid-related side effects and portal vein thrombosis.
      • Hempfling W.
      • Grunhage F.
      • Dilger K.
      • Reichel C.
      • Beuers U.
      • Sauerbruch T.
      Pharmacokinetics and pharmacodynamic action of budesonide in early- and late-stage primary biliary cirrhosis.
      While being an option for remission induction, budesonide is more difficult to taper due to its short half-life and limited dose availability on the market. Both prednisolone and budesonide can cause considerable long-term side effects, and in view of the better long-term effectiveness of systemic immunosuppressants, steroids should in any case not be the mainstay of therapy in AIH.
      • Manns M.P.
      • Woynarowski M.
      • Kreisel M.
      • Lurie Y.
      • Rust C.
      • Zuckerman E.
      • et al.
      Budesonide induces remission more effectively than prednisone in a controlled trial of patients with autoimmune hepatitis.
      ,
      • Woynarowski M.
      • Nemeth A.
      • Baruch Y.
      • Koletzko S.
      • Melter M.
      • Rodeck B.
      • et al.
      Budesonide versus prednisone with azathioprine for the treatment of autoimmune hepatitis in children and adolescents.
      ,
      • Peiseler M.
      • Liebscher T.
      • Sebode M.
      • Zenouzi R.
      • Hartl J.
      • Ehlken H.
      • et al.
      Efficacy and limitations of budesonide as a second-line treatment for patients with autoimmune hepatitis.
      Nonetheless, in patients intolerant to azathioprine, and also intolerant to MMF, steroid monotherapy may be a valid treatment alternative, if bone mineral density is good and remains good, and if the prednisolone dose required can be kept at a maximum of 10 mg/day (in children probably at a maximum of 2.5–5 mg/day). This approach is summarised in Fig. 3 and should be discussed as a possible option with the patient before starting an alternative third-line therapy. In this discussion, it needs to be mentioned that depression is quite frequently observed in patients with AIH, and this seems to be closely associated with steroid use, thus hinting towards a pathogenetic role of steroids in AIH-associated depression.
      • Wong L.L.
      • Fisher H.F.
      • Stocken D.D.
      • Rice S.
      • Khanna A.
      • Heneghan M.A.
      • et al.
      The impact of autoimmune hepatitis and its treatment on health utility.
      Therefore, existing depression and depression risk should be assessed carefully, and psychological support may be required in these patients. An algorithm summarising all recommendations is given in Fig. 3.
      Figure thumbnail gr3
      Fig. 3AIH treatment algorithm.
      In selected patients with AIH who are intolerant to second-line treatment with 6-mercaptopurine and mycophenolate mofetil, steroid monotherapy can be an option. All patients with AIH requiring third-line treatment, should first be discussed in an expert panel, such as the CPMS for patients with rare liver diseases, hosted by the ERN RARE-LIVER. Before starting third-line treatment, inclusion of the patient into a clinical trial should be considered. Insufficient response in patients with AIH is defined by not achieving full remission. Biochemical remission is defined as normal transaminases as well as normal IgG levels and histological remission is defined as a hepatitis activity index score of up to 3 out of 18. 6-TGN, 6-thioguanine nucleotide; AIH, autoimmune hepatitis; CPMS, clinical patient management system; ERN RARE-LIVER, European Reference Network on Hepatological Diseases.

      Third-line therapy

      A number of drugs have been reported to help in the treatment of patients with AIH who do not respond sufficiently to first- and second-line therapy (Table S1). Various schedules of third-line drugs have been used, often depending on local expertise as well as reimbursement rules. To study and evaluate the effectiveness of each third-line protocol, a collaborative effort between all expert centres managing such patients is required. We suggest that patients should only receive third-line therapy on the basis of the algorithm presented in Fig. 3. Patients should be stratified according to why they are receiving third-line therapy: because of insufficient response to standard therapy (expected to be difficult-to-treat), or because of intolerance to standard therapy (expected to be easier-to-treat). Furthermore, third-line protocols should be as standardised as possible, and therefore we have listed the possible regimens including dosing and dosing intervals in Table 1. Results of case series of patients treated according to these protocols should be shared and the results published. Collection of data can be undertaken via the ERN RARE-LIVER.
      This paper does not give firm guidance on the choice of third-line therapy, nor on the question of whether third-line drugs should be combined with standard drugs, or given as an alternative, as no reliable data for such a recommendation are available. However, experience suggests that for patients who are intolerant to first- and second-line treatment, a well-tolerated single third-line drug will probably be sufficient to control liver inflammation. However, for cases with insufficient response under first- and second-line therapy, double or even triple immunosuppression may frequently be needed to induce remission, at least during the initiation of the third-line drug. But the aim of starting third-line treatment is always that the third-line drug will maintain remission on its own. However, for future evaluation of the effectiveness of third-line drugs, it is important to stratify results according to the reason (intolerance or insufficient response) for giving third-line drugs, and to record if (and in what form) combination therapy has been applied. When initiating third-line therapy, in addition to checking and proving the need according to the above recommendations, re-evaluation of the overall health status of the patient is required, not only in order to evaluate the indication for third-line therapy, but to also determine and limit the risks. First of all, in older patients and patients with comorbidities, overall life expectancy and quality of life need to be assessed: Is AIH really the most important disease in this patient, and would progressive disease limit life-expectancy and quality of life more than the side-effects of higher dose standard therapy? Secondly, particularly in children, growth and developmental assessments need to be performed regularly to determine the risks of disease, side-effects of previous therapy and potential risks of alternative third-line therapies. Body weight should be tested in all patient populations, and additional measures for weight control may be required in overweight patients, particularly in those still requiring steroids. Furthermore, cardiovascular and renal risk factors should be checked, as many of the third-line drugs have relevant cardiovascular and renal side-effects. Chronic infections need to be excluded, particularly tuberculosis in the case of anti-TNF therapy. Finally, vaccination status should be assessed and (re-)vaccinations performed as required, preferably prior to commencing third-line therapy.
      No clear preference can be given for single immunosuppressants as third-line treatment since comparative studies are missing and none of the therapies used are approved, yet. However, standardised approaches are needed to make studies comparable and to enable comparative analysis of efficacy in the future.
      Checking the need for third-line therapy by carefully re-assessing disease history, patient adherence, patient preferences and comorbidities will benefit difficult-to-treat patients. Applying the above recommendations should not only lead to better patient care but should also form the basis for scientific progress in evaluating the utility and risks of third-line therapies in AIH.

      Special recommendations for paediatric and adolescent patients with AIH

      While generally speaking AIH is probably the same disease across all age groups, a number of special considerations for paediatric patients need to be stressed. Children and adolescents with AIH may differ from adult patients in several ways: they often present with a cholestatic variant of AIH, certain autoantibodies are more frequently found in children, such as anti-liver-kidney microsome antibodies or anti-liver cytosol type 1,
      • Jiménez-Rivera C.
      • Ling S.C.
      • Ahmed N.
      • Yap J.
      • Aglipay M.
      • Barrowman N.
      • et al.
      Incidence and characteristics of autoimmune hepatitis.
      and the questions of growth and development, as well as psychosocial aspects and questions of adherence, may present special challenges in paediatric care.
      Up to about 50% of children presenting with features of AIH may later be found to have underlying cholestatic liver disease, termed by some autoimmune sclerosing cholangitis or AIH/PSC overlap syndrome. Therefore, sclerosing cholangitis should be excluded by cholangiography (magnetic resonance cholangiopancreatography), and possibly by repeating liver biopsy.
      • Mieli-Vergani G.
      • Vergani D.
      • Baumann U.
      • Czubkowski P.
      • Debray D.
      • Dezsofi A.
      • et al.
      Diagnosis and management of pediatric autoimmune liver disease: ESPGHAN Hepatology Committee Position Statement.
      As typical findings of sclerosing cholangitis may be subtle and can be missed by both methods, follow-up cholangiography and sometimes also follow-up liver biopsy may be required, and are strongly recommended for all children and adolescents failing to reach remission. These children should also be screened for underlying inflammatory bowel disease by measuring faecal calprotectin followed by a colonoscopy if elevated.
      • Mieli-Vergani G.
      • Vergani D.
      • Baumann U.
      • Czubkowski P.
      • Debray D.
      • Dezsofi A.
      • et al.
      Diagnosis and management of pediatric autoimmune liver disease: ESPGHAN Hepatology Committee Position Statement.
      Other differential diagnoses must also be considered in an age-related fashion: In toddlers, careful evaluation of metabolic disorders must be undertaken. In both children and young adults, Wilson's disease must be excluded by measuring ferroxidase and 24-hour urine copper excretion, by slit-lamp examination for Kayser-Fleischer rings, by genetic analysis and, if in doubt, by measuring liver tissue copper content quantitatively in a liver biopsy sample.
      Previous studies on the treatment of paediatric AIH include only one randomized trial.
      • Woynarowski M.
      • Nemeth A.
      • Baruch Y.
      • Koletzko S.
      • Melter M.
      • Rodeck B.
      • et al.
      Budesonide versus prednisone with azathioprine for the treatment of autoimmune hepatitis in children and adolescents.
      That is why treating this patient group is mainly based on case reports, observational and retrospective studies, adult studies, and experience. Despite these difficulties, a paediatric scoring system for autoimmune liver disease and a treatment algorithm have been proposed by The European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN), which may help in the management of paediatric AIH.
      • Mieli-Vergani G.
      • Vergani D.
      • Baumann U.
      • Czubkowski P.
      • Debray D.
      • Dezsofi A.
      • et al.
      Diagnosis and management of pediatric autoimmune liver disease: ESPGHAN Hepatology Committee Position Statement.
      Paediatric patients have a comparable remission rate as adults on first-line therapy, with about 50% of patients achieving normal ALT levels 2–3 months after starting treatment.
      • Cuarterolo M.
      • Ciocca M.
      • López S.
      • Araujo M.
      • Álvarez F.
      Autoimmune hepatitis in children: prednisone plus azathioprine vs cyclosporine: a randomized trial.
      ,
      • Pniewska A.
      • Sobolewska-Pilarczyk M.
      • Pawłowska M.
      Evaluation of the effectiveness of treatment with prednisone and azathioprine of autoimmune hepatitis in children.
      If remission is not achieved, monitoring of azathioprine metabolites should rely on the 6-MMP/6-TG ratio being below 4 rather than on sole 6-TGN levels. On their own, 6-TGN levels appear to only poorly correlate with biochemical remission in paediatrics.
      • Sheiko M.A.
      • Sundaram S.S.
      • Capocelli K.E.
      • Pan Z.
      • McCoy A.M.
      • Mack C.L.
      Outcomes in pediatric autoimmune hepatitis and significance of azathioprine metabolites.
      ,
      • Bolia R.
      • Rajanayagam J.
      • Hardikar W.
      Lower 6-MMP/6-TG ratio may be a therapeutic target in pediatric autoimmune hepatitis.
      Although studies on the combination of allopurinol and low-dose azathioprine in children with AIH have not been published, it seems reasonable to use the same approach in children as in adults, with special attention to 6-MMP/6-TGN ratio.
      Relapse during maintenance therapy in childhood and adolescence requires a special diagnostic and therapeutic approach: one reason may be accidental undertreatment, because as children grow, continued re-evaluation and adaptation of dosage per body weight is needed. Non-adherence is a challenge in any age group, but is much more commonly seen and at the same time more complex in adolescence. It is probably the most common cause of relapse during this phase in life. Managing adherence well must be considered a multidisciplinary task.
      • Trevizoli I.C.
      • Pinedo C.S.
      • Teles V.O.
      • Seixas R.B.P.M.
      • de Carvalho E.
      Autoimmune hepatitis in children and adolescents: effect on quality of life.
      In smaller children, non-adherence may also occur, for example if the child dislikes the medication or cannot swallow the tablet. Furthermore, psychosocial problems of parenting may also be responsible for non-adherence. In type 2 AIH, representing about 10% of the paediatric patients with AIH,
      • Cuarterolo M.
      • Ciocca M.
      • López S.
      • Araujo M.
      • Álvarez F.
      Autoimmune hepatitis in children: prednisone plus azathioprine vs cyclosporine: a randomized trial.
      ,
      • Vitfell-Pedersen J.
      • Jørgensen M.H.
      • Müller K.
      • Heilmann C.
      Autoimmune hepatitis in children in Eastern Denmark.
      repeated relapse is not uncommon, and second- or third-line treatment is frequently needed.
      Because of the longer expected lifespan of a child with AIH, the long-term effects of immunosuppressive treatment should be taken into consideration in a paediatric patient with AIH, and therapy may need to be adapted in different life phases accordingly. Intolerance and side effects of therapy may have a more severe impact on adherence and quality of life in paediatric patients. Studies on 6-MP in paediatric AIH are lacking, however, data from acute lymphoid leukaemia and inflammatory bowel disease in childhood support the safety of 6-MP in this age group. Therefore, 6-MP is also an option in children if azathioprine is not tolerated. MMF is available as a liquid formulation, is often used for transplantation in children and its dosing can be easily regulated in small children. In general, if monotherapy with prednisolone on a higher dose appears to be required to reach and maintain remission, other alternatives should be discussed with the parents and child, in particular in adolescents. Growth and bone mineralisation should be monitored closely, and third-line treatment may be considered if side effects on standard therapy become worrisome, even if the child is in remission. Non-adherence due to the cosmetic side effects of prednisolone can be a major issue during adolescence and can also be considered a form of drug intolerance leading to second- and third-line therapy. Patient involvement in the decision process seems important. Furthermore, as patients transition into adult life, a return to standard therapy should probably be attempted.
      The number of paediatric studies on third-line therapy is very low and the number of patients included small (Table S1). This highlights the need for multicentre studies and close collaborations together with adult hepatologists. Two observational paediatric studies on calcineurin inhibitors indicate that remission can be achieved in about 75% of cases within 6 months and that well-monitored usage of tacrolimus is safe in children.
      • Cuarterolo M.
      • Ciocca M.
      • López S.
      • Araujo M.
      • Álvarez F.
      Autoimmune hepatitis in children: prednisone plus azathioprine vs cyclosporine: a randomized trial.
      ,
      • Marlaka J.R.
      • Papadogiannakis N.
      • Fischler B.
      • Casswall T.H.
      • Beijer E.
      • Németh A.
      Tacrolimus without or with the addition of conventional immunosuppressive treatment in juvenile autoimmune hepatitis.
      However, we lack long-term data, which are urgently needed due to the possible toxic effects of these drugs. Other third-line drugs (Table S1) in paediatrics can only be supported by case reports or adult data. The lack of data in this area underlines the need for prospective databases and multicentre paediatric studies.

      Abbreviations

      AIH, autoimmune hepatitis; ALP, alkaline phosphatase; ALT, alanine aminotransferase; CAP, controlled attenuation parameter; HAI, hepatitis activity index; MCV, mean corpuscular erythrocyte volume; NAFLD, non-alcoholic fatty liver disease; NASH, non-alcoholic steatohepatitis; PBC, primary biliary cholangitis; PSC, primary sclerosing cholangitis.

      Financial support

      This position statement was supported by the European Reference Network on Hepatological Diseases (ERN RARE-LIVER).

      Authors' contributions

      AWL and MV wrote the manuscript. AL and MS designed the figures. MV and MHJ created the tables. AWL, MV, MS, MHJ, HY, THK, DK and MPM reviewed and edited the manuscript, figures and tables.

      Conflict of interest

      The authors declare no conflicts of interest that pertain to this work.
      Please refer to the accompanying ICMJE disclosure forms for further details.

      Acknowledgements

      The authors thank EASL and ESPGHAN for supporting ERN RARE-LIVER in their efforts for the care of patients with rare liver diseases, and to the European Commission and the Free and Hanseatic State of Hamburg for financial support for the ERN RARE-LIVER.

      Supplementary data

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