Autoimmune hepatitis and its variant syndromes

Incidence and Predictors of an Abnormal Liver Function Test Among 674 Systemic Sclerosis Patients: A Cohort Study

Background

Abnormal liver function tests (LFTs) can indicate cirrhosis or liver cancer leading to mortality among systemic sclerosis (SSc) patients. No recent studies have investigated the clinical predictors of an abnormal LFT in SSc. We aimed to determine the incidence of abnormal LFT (including from hepatitis and cholestasis) and to identify its clinical predictors in SSc patients.

Methods

An historical cohort was conducted on 674 adult SSc patients who attended the Scleroderma Clinic, Khon Kaen University, between January 2012 and November 2019 and who underwent routine screening for LFT. A Cox regression was used to analyze the clinical predictors of abnormal LFT.

Results

Four hundred and thirty cases, representing 4190 person-years, had abnormal LFTs (viz, from hepatitis, cholestasis, and cholestatic hepatitis) for an incidence rate of 10.2 per 100 person-years. The respective incidence of hepatitis, cholestasis, and cholestatic hepatitis was 20.5, 12.9, and 20.4 per 100 person-years. The respective median first-time detection of hepatitis, cholestasis, and cholestatic hepatitis was 3.0, 5.9, and 2.8 years, and none had signs or symptoms suggestive of liver disease. According to the Cox regression analysis, the predictors of an abnormal LFT in SSc were elderly onset of SSc (hazard ratio (HR) 1.02), alcoholic drinking (HR 1.74), high modified Rodnan Skin Score (mRSS) (HR 1.03), edematous skin (HR 2.94), Raynaud's phenomenon (HR 1.39), hyperCKaemia (HR 1.88), and methotrexate use (HR 1.55). In contrast, current sildenafil treatment (HR 0.63) and high serum albumin (HR 0.70) were protective factors.

Conclusion

Occult hepatitis, cholestasis, and cholestatic hepatitis can be detected in SSc patients using LFT screening, especially in cases of early disease onset. The long-term outcome is uncertain, and more longitudinal research is required.

Positive familial history for metabolic traits predisposes to early and more severe alcoholic cirrhosis: A cross-sectional study

BACKGROUND & AIMS

Familial aggregation of metabolic traits in NAFLD is well documented. However, relevance of these traits in alcoholic cirrhosis is not well studied. We aimed to explore the association of family history of metabolic traits with age at diagnosis, severity and complications of alcoholic cirrhosis.

METHODS

In a cross-sectional study, all consecutive patients with alcoholic cirrhosis presenting to our tertiary care centre were included. Family and personal history, demographic characteristics, medical history, anthropometric measurements and laboratory data were recorded. The amount and duration of alcohol consumption were also carefully recorded.

RESULTS

Out of 1084 alcoholic cirrhotics (age 48.5 ± 10.1 years, all males), family history for metabolic traits was documented in 688 (63.5%) patients. These patients had younger age at diagnosis, increased incidence of jaundice, ascites, variceal bleed and hepatic encephalopathy with consequently higher MELD and CTP score. These patients developed cirrhosis despite shorter median duration (13 years, IQR 7-20 vs 21, IQR 18-25) and lesser amount of alcohol consumption (74 g/d, IQR 24-96 vs 144, IQR 100-148). Patients with both family and personal history of metabolic traits had a higher risk by 3.3 times (95% CI 2.2-4.8) of an early age at diagnosis, 13.2 times (95% CI 8.7-20.1) of progression to cirrhosis with lesser amount of alcohol consumption and 4.6 times (95% CI 3.1-6.9) with lesser duration of alcohol consumption.

CONCLUSIONS

Positive family and personal history of metabolic traits predispose to alcoholic cirrhosis with an earlier age at onset and more severity despite lesser exposure to alcohol.

The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelines

Primary biliary cholangitis (formerly known as primary biliary cirrhosis, PBC) is an autoimmune liver disease in which a cycle of immune mediated biliary epithelial cell injury, cholestasis and progressive fibrosis can culminate over time in an end-stage biliary cirrhosis. Both genetic and environmental influences are presumed relevant to disease initiation. PBC is most prevalent in women and those over the age of 50, but a spectrum of disease is recognised in adult patients globally; male sex, younger age at onset (<45) and advanced disease at presentation are baseline predictors of poorer outcome. As the disease is increasingly diagnosed through the combination of cholestatic serum liver tests and the presence of antimitochondrial antibodies, most presenting patients are not cirrhotic and the term cholangitis is more accurate. Disease course is frequently accompanied by symptoms that can be burdensome for patients, and management of patients with PBC must address, in a life-long manner, both disease progression and symptom burden. Licensed therapies include ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), alongside experimental new and re-purposed agents. Disease management focuses on initiation of UDCA for all patients and risk stratification based on baseline and on-treatment factors, including in particular the response to treatment. Those intolerant of treatment with UDCA or those with high-risk disease as evidenced by UDCA treatment failure (frequently reflected in trial and clinical practice as an alkaline phosphatase >1.67 × upper limit of normal and/or elevated bilirubin) should be considered for second-line therapy, of which OCA is the only currently licensed National Institute for Health and Care Excellence recommended agent. Follow-up of patients is life-long and must address treatment of the disease and management of associated symptoms.

Adult idiopathic cholestasis: a condition more common in the Canadian Inuit?

Despite extensive investigations, some patients have no identifiable cause for their cholestatic liver enzyme abnormalities. The aim of this study was to document the clinical, laboratory, radiologic and histologic features of adult patients with idiopathic cholestasis (AIC). A computerised database of referred patients to a tertiary care hospital outpatient department for assessment of hepatobiliary disorders between 2005 and 2015 was employed to identify and describe features associated with AIC. Of 6,560 patient referrals, sufficient documentation to warrant a diagnosis of AIC was present in 17 (0.26%) cases. Of the 17, a disproportionate number were Canadian Inuit (7/60, 12% Inuit referrals vs. 10/6,500, 0.16% non-Inuit referrals, p<0.0001). The median age of the 17 subjects was 57 years and nine (53%) were female. Clinical and/or laboratory evidence of autoimmune disorders was present in six (35%) cases. Clinical features of hepatic decompensation, radiologic findings in keeping with cirrhosis and histologic confirmation of cirrhosis were present in 47%, 31% and 42% of individuals, respectively. There were no significant improvements in cholestatic liver enzymes and function tests in those treated with ursodiol and/or immunomodulants (n=7) compared to those left untreated (n=10). In conclusion, AIC is a rare condition diagnosed by exclusion. It appears to be more common in the Canadian Inuit population and those with autoimmune disorders. Advanced liver disease is a frequent finding at presentation. Intervention with ursodiol and/or immunomodulants does not appear to be of therapeutic value.

[Autoimmune hepatitis: Immunological diagnosis]

Autoimmune hepatopathies (AIHT) including autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune cholangitis (AIC), represent an impressive entities in clinical practice. Their pathogenesis is not perfectly elucidated. Several factors are involved in the initiation of hepatic autoimmune and inflammatory phenomena such as genetic predisposition, molecular mimicry and/or abnormalities of T-regulatory lymphocytes. AIHT have a wide spectrum of presentation, ranging from asymptomatic forms to severe acute liver failure. The diagnosis of AIHT is based on the presence of hyperglobulinemia, cytolysis, cholestasis, typical even specific circulating auto-antibodies, distinctive of AIH or PBC, and histological abnormalities as well as necrosis and inflammation. Anti-F actin, anti-LKM1, anti-LC1 antibodies permit to distinguish between AIH type 1 and AIH type 2. Anti-SLA/LP antibodies are rather associated to more severe hepatitis, and particularly useful for the diagnosis of seronegative AIH for other the antibodies. Due to the relevant diagnostic value of anti-M2, anti-Sp100, and anti-gp210 antibodies, the diagnosis of PBC is more affordable than that of PSC and AIC. Based on clinical data, the immunological diagnosis of AIHT takes advantage of the various specialized laboratory techniques including immunofluorescence, immunodot or blot, and the Elisa systems, provided of a closer collaboration between the biologist and the physician.

Diagnostic considerations for cholestatic liver disease

Cholestatic liver disease results from insufficient bile synthesis, secretion and/or flow through the biliary tract. Common presenting features include fatigue, pruritus, and cholestatic liver enzyme abnormalities wherein elevations of serum alkaline phosphatase and gamma-glutamyltransferases levels exceed those of alanine and aspartate aminotransferases. With prolonged cholestasis, fat soluble vitamin deficiencies, fibrosis, cirrhosis, and, on occasion, carcinoma of the biliary tract or liver can occur. Once mechanical obstruction to bile flow has been ruled out, the majority of causes can be classified as immune-mediated, infectious, or miscellaneous. Because specific therapeutic options are increasing for many causes of cholestasis, an accurate diagnosis is an important first step towards treatment. Thus, this review focuses on the diagnostic features of non-mechanical causes of cholestasis.

Autoimmune Hepatitis Overlap Syndromes and Liver Pathology

Autoimmune hepatitis (AIH) may have an atypical serum alkaline phosphatase elevation, antimitochondrial antibodies, histologic features of bile duct injury/loss, or cholangiographic findings of focal biliary strictures and dilations. These manifestations characterize the overlap syndromes. Patients can be classified as having AIH with features of primary biliary cholangitis, primary sclerosing cholangitis, or a cholestatic syndrome. The gold standard of diagnosis is clinical judgment. Histologic evaluation is a major diagnostic component. Treatment is based on algorithms; outcomes vary depending on the predominant disease component. Combination therapy has been the principal recommendation.

Autoimmune hepatitis and long-term disease course in children in Turkey, a single-center experience

INTRODUCTION

The aim of this study is to determine clinic and laboratory features, treatment protocols, treatment responses, and long term follow-up of children with autoimmune hepatitis (AIH) in a region of Turkey followed at Ege University.

MATERIALS AND METHODS

The records of 47 children with AIH between 1998 and 2012 were retrospectively analyzed for clinical profiles, treatment response, relapse rate, and long-term side effects.

RESULTS

The median age of the children was 10±4.1 years (55.3% females). A total of 29 patients presented with chronic hepatitis (61.7%). According to the autoantibody profiles, 40 (85.1%) and seven (14.9%) cases were classified as type 1 and type 2, respectively. Presentation with acute hepatitis and chronic hepatitis was significantly higher in type 1 disease. Laboratory findings at presentation was found similar among races as well as AIH types (P>0.05). The prednisolone was used for remission induction in 37 patients; 86.4% (n: 32) achieved a complete response, 2.7% (n: 1) achieved a partial response, and four patients (10.8%) showed no response. Maintenance was attained by low-dose steroid plus thiopurine and relapse in steroid responders (n: 32) was 9.4% (n: 3) at 8, 12, and 48 months. A total of 36% (n: 24) had neither acute nor chronic treatment side effects. Bone marrow suppression was observed in five patients and hyperglycemia was observed in one patient (10.6 and 2.1%), respectively.

CONCLUSION

AIH type 1 prevails in children in a region of Turkey during the second decade of life. Low-dose corticosteroids combined with azathioprine are found.

Autoimmune cholangitis: a variant syndrome of autoimmune hepatitis

Autoimmune cholangitis (AIC) or autoimmune cholangiopathy is a chronic inflammation of liver and a variant syndrome of autoimmune hepatitis (AIH). We present a case of an adult female who had biochemical features of cholestasis and transaminasemia but aminotransferases were not in the hepatitis range and had histological evidence of bile duct injury which was subsequently diagnosed as autoimmune cholangitis.

Cholestatic phenotypes of autoimmune hepatitis

Autoimmune hepatitis can have cholestatic features that are outside the codified diagnostic criteria. These features have uncertain effects on the clinical presentation and progression of disease. Patients with autoimmune hepatitis can have antimitochondrial antibodies and coincidental bile duct injury or loss (2%-13% of patients), focal biliary strictures and dilations based on cholangiography (2%-11%), or histologic changes of bile duct injury or loss in the absence of other features (5%-11%). These findings probably represent atypical manifestations of autoimmune hepatitis or variants of primary biliary cirrhosis or primary sclerosing cholangitis, depending on the predominant findings. Serum levels of alkaline phosphatase and γ-glutamyl transferase, histologic features of bile duct injury, and findings from cholangiography are associated with responsiveness to corticosteroid therapy and individualized alternative treatments. Corticosteroid therapy, in combination with low-dose ursodeoxycholic acid, has been promulgated by international societies, but these recommendations are not based on strong evidence. The frequency, variable outcomes, and uncertainties in diagnosis and management of the cholestatic phenotypes must be addressed by a collaborative investigational network. This network should define the genetic and pathologic features of these disorders, standardize their nomenclature, and establish a treatment algorithm. In this review, the different cholestatic phenotypes of autoimmune hepatitis, mechanisms of pathogenesis, current management strategies and outcomes, and opportunities for improving understanding and therapy are presented.

Total serum bilirubin as a negative prognostic factor in idiopathic canine chronic hepatitis

Total serum bilirubin (TBIL) is used as a prognostic factor in chronic hepatitis (CH) in human beings. To date, the authors are unaware of any studies looking at the value of TBIL as a prognostic factor in idiopathic canine CH. The objective of the current study was to assess if TBIL is a negative prognostic factor in idiopathic canine CH, and to identify other prognostic factors. Thirty-nine dogs with histologically confirmed idiopathic CH admitted to 2 referral centers between 1999 and 2010 were included in the study. Patients with concurrent diseases that could affect TBIL or the survival time were excluded. Total serum bilirubin was measured prior to liver biopsy, and CH was diagnosed according to standardized histological criteria. Survival time was calculated from time of diagnosis to time of death or euthanasia. Cox proportional hazard analysis was performed to identify prognostic factors. The mean survival time for the 39 dogs included in the analysis was 197 days (1-2,677), and the mean total serum bilirubin was 11 μmol/l (2-265). Total serum bilirubin was statistically significantly associated with survival (odds ratio = 1.082, P = 0.047) as were weight (odds ratio = 1.028, P = 0.028) and the presence of ascites (odds ratio = 6.758, P = 0.013). The current study demonstrates that TBIL could be used as an additional prognostic factor in canine CH.

Diagnosis and management of the overlap syndromes of autoimmune hepatitis

BACKGROUND

Autoimmune hepatitis may have cholestatic features that are outside the classical phenotype and that resemble findings in other immune-mediated liver diseases. These cholestatic phenotypes have been designated 'overlap syndromes'.

OBJECTIVES

To recognize the overlap syndromes in adults and manage them appropriately.

METHODS

The MEDLINE database was reviewed for published experiences from 1984 to 2013.

RESULTS

Patients with autoimmune hepatitis may exhibit features of primary biliary cirrhosis (7% to 13%), primary sclerosing cholangitis (6% to 11%) or a cholestatic syndrome without other diagnostic features (5% to 11%). These mixed phenotypes may represent classical autoimmune hepatitis with atypical features, transition states in the evolution of classical cholestatic syndromes, concurrent separate diseases or pathogenically distinct disorders. The 'Paris criteria' have been endorsed for the diagnosis of the overlap syndrome with primary biliary cirrhosis, and treatment with conventional immunosuppressive therapy alone or in combination with low-dose ursodeoxycholic acid can be guided by the serum alkaline phosphatase level. The overlap syndrome with primary sclerosing cholangitis or with cholestasis without diagnostic features is commonly treated with immunosuppressive therapy and ursodeoxycholic acid. Responses are variable and commonly incomplete (20% to 100% improvement) depending on the degree of cholestasis.

DISCUSSION

The overlap syndromes are clinical descriptions rather than pathological entities, and the dominant component of the disease determines its designation and therapy. Cholestatic findings in autoimmune hepatitis influence the response to immunosuppressive therapy.

CONCLUSION

The overlap syndromes must be considered in patients with autoimmune hepatitis and cholestatic findings, concurrent inflammatory bowel disease or steroid-refractory disease.

Overlap syndromes: an emerging diagnostic and therapeutic challenge

Overlap syndrome in hepatology is emerging as a diagnostic and therapeutic challenge, which is further complicated by the present gaps in the information regarding the immunopathogenesis of these diseases. The present review represents a concise review of literature on overlap syndromes with emphasis on prevalence, etiopathogenesis, clinical presentation, diagnosis, and management of true overlap syndromes.

The overlap syndromes of autoimmune hepatitis

Autoimmune hepatitis has two major variant phenotypes in which the features of classical disease are co-mingled with those of primary biliary cirrhosis or primary sclerosing cholangitis. These overlap syndromes lack codified diagnostic criteria, established pathogenic mechanisms, and confident management strategies. Their clinical importance relates mainly to the identification of patients who respond poorly to conventional corticosteroid treatment. Scoring systems that lack discriminative power have been used in their definition, and a clinical phenotype based on pre-defined laboratory and histological findings has not been promulgated. The frequency of overlap with primary biliary cirrhosis is 7-13 %, and the frequency of overlap with primary sclerosing cholangitis is 8-17 %. Patients with autoimmune hepatitis and features of cholestatic disease must be distinguished from patients with cholestatic disease and features of autoimmune hepatitis. Variants of the overlap syndromes include patients with small duct primary sclerosing cholangitis, antimitochondrial antibody-negative primary biliary cirrhosis, autoimmune sclerosing cholangitis, and immunoglobulin G4-associated disease. Conventional corticosteroid therapy alone or in conjunction with ursodeoxycholic acid (13-15 mg/kg daily) has been variably effective, and cyclosporine, mycophenolate mofetil, and budesonide have been beneficial in selected patients. The key cholestatic features that influence the prognosis of autoimmune hepatitis must be defined and incorporated into the definition of the syndrome rather than rely on designations that imply the co-mingling of different diseases with manifestations of variable clinical relevance. The overlap syndromes in autoimmune hepatitis are imprecise, heterogeneous, and unfounded, but they constitute a clinical reality that must be accepted, diagnosed, refined, treated, and studied.

Antibodies to soluble liver antigen in patients with various liver diseases: a multicentre study

BACKGROUND

Antibodies to soluble liver antigen (anti-SLA) are specific serological markers of autoimmune hepatitis (AIH). The clinical significance and frequency of anti-SLA have never been reported among AIH patients from Italy and Turkey. To retrospectively assess the estimated prevalence, sensitivity, specificity and clinical significance of anti-SLA in AIH and various liver diseases.

METHODS

A total of 986 patients who had been tested for serum anti-SLA were included in study. The presence of anti-SLA was detected using recombinant enzyme linked immunosorbent assay and immuno-blot. The general characteristics and outcome of patients were obtained from their medical records.

RESULTS

Antibodies to SLA were found in 30 (3%) of 986 patients. Of these, 27 (90%) had AIH and its variants, whereas the remaining three (10%) had primary biliary cirrhosis. The prevalence of anti-SLA was 9% in AIH patients from Italy and 15% in patients from Turkey. The specificity of these antibodies was 99.5%, whereas sensitivity was 11%. The positive predictive and negative predictive values were 90% and 77.5% respectively (95% confidence interval). Biochemical remission was achieved in 90% of anti-SLA positive AIH patients, but relapse after immunosuppressive withdrawal or during maintenance therapy was observed in 53% of the patients.

CONCLUSIONS

Seropositivity for anti-SLA occurs at similar frequencies in AIH patients from different geographical regions and ethnic groups. The sensitivity of anti-SLA is low, but it has high specificity for AIH. Additional studies are necessary to prove clinical significance of anti-SLA in AIH.

[Primary biliary cirrhosis-autoimmune hepatitis overlap syndrome in a patient with chronic hepatitis B infection]

We describe the case of a female patient with a previous diagnosis of primary biliary cirrhosis (PBC) and chronic hepatitis B in inactive phase who developed increased transaminase levels with no evidence of hepatitis B virus reactivation while receiving ursodeoxycholic acid treatment. A liver biopsy showed changes compatible with overlapping autoimmune hepatitis (AIH). Budesonide treatment achieved normalization of transaminase levels. We provide a review of PBC and AIH overlap syndrome and discuss the particular features of this case that led us to this diagnosis, as well as the treatment provided.

Immunological diseases of the pancreatico-hepatobiliary system: update on etiopathogenesis and cross-sectional imaging findings

Immunological diseases of the hepatobiliary system and the pancreas include a broad spectrum of disorders that manifest characteristic histopathology/serology and variable clinical features and imaging findings. Recent studies have thrown fresh light on the complex role of genetics and autoimmunity in the pathogenesis and natural history of these diverse disorders that include autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis, IgG4-related cholangitis, overlap/outlier syndromes, and autoimmune pancreatitis.

Autoimmune hepatitis in special patient populations

Autoimmune hepatitis has diverse clinical phenotypes that challenge conventional diagnostic criteria and treatment strategies. The goals of this review are to characterize these special populations and provide guidelines for their management. Patients with acute or acute severe (fulminant) presentations may have centrilobular zone 3 hepatic necrosis, but they can respond to conventional corticosteroid therapy. Asymptomatic mild disease warrants corticosteroid treatment because spontaneous resolution is uncertain and 10-year survival is less than expected. Male gender or the absence of conventional autoantibodies does not preclude the diagnosis or need for treatment, and patients with cholestatic changes warrant cholangiography and possible combination therapy with ursodeoxycholic acid. Different ethnic groups commonly have advanced hepatic fibrosis, rapidly progressive disease, or cholestatic features, and elderly patients typically respond well to corticosteroid therapy. Pregnancy is usually well-tolerated by mother and foetus but requires protection against postpartum exacerbation. Special populations must be recognized and treated with tailored regimens.

Performance parameters of the conventional serological markers for autoimmune hepatitis

BACKGROUND

Autoimmune hepatitis is defined by a conventional battery of autoantibodies that may also be present in other liver diseases.

AIMS

To define the performance parameters of the conventional autoantibodies for autoimmune hepatitis, determine the diagnostic implications of simultaneous autoantibody production, and assess the performances of serological assays based on indirect immunofluorescence and enzyme immunoassay.

METHODS

In this study, 265 adults satisfying codified criteria for autoimmune hepatitis and 342 adults who satisfied conventional diagnostic criteria for another chronic liver disease were each assessed for the conventional autoantibodies.

RESULTS

Antinuclear antibodies, smooth muscle antibodies, and antibodies to liver kidney type 1 had sensitivities of only 32, 16, and 1%, respectively, for the diagnosis of autoimmune hepatitis, and their diagnostic accuracy ranged from 56 to 61%. The combination of antinuclear antibodies and smooth muscle antibodies at presentation had superior sensitivity (43%), specificity (99%), positive (97%) and negative (69%) predictabilities, and diagnostic accuracy (74%) than each marker alone. The occurrence of multiple autoantibodies was lower in other chronic liver diseases than in autoimmune hepatitis (8% versus 51%, p < 0.000001). The enzyme immunoassay for antinuclear antibodies had an accuracy that was not discriminative for autoimmune hepatitis (p = 0.06).

CONCLUSIONS

Isolated autoantibodies have a low diagnostic accuracy for autoimmune hepatitis. Concurrent antinuclear antibodies and smooth muscle antibodies have superior performance parameters. The enzyme immunoassay for antinuclear antibodies performs less well than the assay based on indirect immunofluorescence.

Overlap syndromes: the International Autoimmune Hepatitis Group (IAIHG) position statement on a controversial issue

Some patients present with overlapping features between disorders within the spectrum of autoimmune liver diseases (i.e. autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC)) and are commonly classified as having an "overlap syndrome". Standardized definitions of "overlap syndromes" are lacking. The aim of this report by the International Autoimmune Hepatitis Group (IAIHG) is to evaluate if there are important reasons to classify conditions with overlapping features between autoimmune liver diseases as separate diagnostic entities. Definition of diagnostic criteria for overlap conditions can only be arbitrary. The IAIHG scoring system for diagnosis of AIH has been widely used to diagnose "overlap syndromes", but was not intended for such use and has not proven to be an efficient tool for this purpose. Some patients with overlapping features between a cholestatic and hepatitic disorder appear to benefit from treatment with a combination of ursodeoxycholic acid and immunosuppressants, but this strategy is not evidence-based, and it seems unjustified to define new diagnostic groups in this regard. The IAIHG suggests that patients with autoimmune liver disease should be categorized according to the predominating feature(s) as AIH, PBC, and PSC/small duct PSC, respectively, and that those with overlapping features are not considered as being distinct diagnostic entities. The IAIHG scoring system should not be used to establish subgroups of patients. Patients with PBC and PSC with features of AIH should be considered for immunosuppressive treatment. Due to the low prevalence of such "overlap syndromes", prospective interventional therapeutic trials cannot be expected in the foreseeable future.

Evaluating distinctive features for early diagnosis of primary sclerosing cholangitis overlap syndrome in adults with autoimmune hepatitis

AIMS

Overlap syndromes constitute a significant proportion of autoimmune liver disease. Our aim was to describe our cohort and evaluate practical methods of correctly diagnosing autoimmune hepatitis/primary sclerosing cholangitis overlap syndrome as early as possible clinically.

METHODS

118 autoimmune hepatitis patients were screened for cholestatic liver function tests. 24 patients with cholestatic liver function tests were investigated for possible primary sclerosing cholangitis by clinicopathological review and magnetic resonance cholangiography. Retrospectively, potential predictors of autoimmune hepatitis/primary sclerosing cholangitis overlap syndrome were compared with a control group.

RESULTS

Overlap syndrome was diagnosed in twelve (50%) of 24 autoimmune hepatitis patients with recent cholestasis. The cholestatic group had a lower AST (p=0.012) and International Autoimmune Hepatitis Group (IAHG) score (p=0.102), and higher IgM (p=0.002) at disease presentation. More patients in the cholestatic group developed ulcerative colitis (p=0.138).

CONCLUSIONS

Identifying AIH / PSC overlap syndrome at diagnosis is often difficult. Certain clinical and biochemical features should alert the clinician. All patients with AIH, and biochemical cholestasis should be investigated with MRC.

A girl with type 1 diabetes and a yellowish appearance

Type 1 diabetes mellitus in children has been associated with other autoimmune diseases, especially coeliac disease and autoimmune thyroiditis. This association may be the result of a common pathogenic background. We describe the case of a girl with type 1 diabetes mellitus who developed icterus due to autoimmune hepatitis, a disease rarely found in children. Thyroiditis-associated and diabetes-associated autoantibodies were also present. Human leucocyte antigen typing revealed DRB1*03 heterozygosity, which has been associated with the occurrence of both autoimmune hepatitis and type 1 diabetes. This finding implies that similar pathogenic pathways may be involved in different autoimmune diseases including type 1 diabetes and autoimmune hepatitis. The patient was successfully treated with prednisolone and azathioprine. Autoimmune hepatitis can be a serious co-occurring disease in patients with type 1 diabetes.

[Autoimmune hepatitis: diagnostic and therapeutic up-to-date]

Autoimmune hepatitis is a disorder of unknown aetiology that occurs in children and adults of all ages with a female predominance. The spectrum of presentation is wide, ranging from no symptoms to acute liver failure. The diagnosis is based on high level serum gammaglobulins, characteristic circulating autoantibodies and histologic abnormalities (necrosis and inflammation). Autoimmune hepatitis is classified on the basis of the autoantibody pattern: type 1 (antinuclear and/or smooth muscle antibodies) is the classic form whereas type II (liver-kidney microsome 1 antibody) is much less common and occurs mainly in childhood. Mixed forms of autoimmune hepatitis that share features with other putative autoimmune liver diseases, primary biliary cirrhosis and primary sclerosing cholangitis, have been described. Because of therapeutic issues, it is important to distinguish autoimmune hepatitis from other forms of hepatitis and the use of diagnostic scoring systems may be helpful. The treatment of autoimmune hepatitis has not changed for the past 30 years. It consists of corticosteroids associated with azathioprine. This treatment is rapidly effective but usually only suspensive. Relapse after treatment withdrawal is the rule (80% of cases). The main risk factor of recurrence is the degree of residual inflammation on liver biopsy. The frequency of side effects justifies an attempt of drug discontinuation provided that criteria of clinical, biochemical and histological remission are achieved after at least 2 years of treatment.

Overlap syndrome of autoimmune chronic liver diseases: MRI findings

PURPOSE

To describe the MR findings of overlap syndromes of autoimmune chronic liver diseases.

METHODS

Review of clinical and radiological databases between March 2001 and July 2008 for patients with a clinical diagnosis and liver biopsy features compatible with overlap syndrome who had also undergone an abdominal MRI yielded 15 adult patients. MR features of overlap syndrome were reviewed by two radiologists by consensus. Two radiologists independently reviewed the studies in a blinded fashion for primary sclerosing cholangitis (PSC)-type or non-PSC-type features to assess interobserver agreement.

RESULTS

PSC-type and non-PSC-type overlap syndrome had distinctive MR features. In the consensus review, all 12 patients with PSC-type overlap syndrome were correctly identified. Imaging findings included central macroregeneration (N = 9), peripheral atrophy (N = 7), biliary duct beading (N = 12), biliary dilation (N = 10), or a combination of all four findings (N = 7). The presence of any of the first three features had 100% specificity for a PSC-type overlap syndrome. Patients with non-PSC-type overlap (N = 3) showed relatively normal liver morphology (N = 3) and minimal biliary ductal dilatation in one patient. There was good interobserver agreement (kappa = 0.76).

CONCLUSION

Patients with serologic or pathologic evidence of AIH or PBC with imaging features of PSC may have PSC-type overlap syndrome.

Difficult treatment decisions in autoimmune hepatitis

Treatment decisions in autoimmune hepatitis are complicated by the diversity of its clinical presentations, uncertainties about its natural history, evolving opinions regarding treatment end points, varied nature of refractory disease, and plethora of alternative immunosuppressive agents. The goals of this article are to review the difficult treatment decisions and to provide the bases for making sound therapeutic judgments. The English literature on the treatment problems in autoimmune hepatitis were identified by Medline search up to October 2009 and 32 years of personal experience. Autoimmune hepatitis may have an acute severe presentation, mild inflammatory activity, lack autoantibodies, exhibit atypical histological changes (centrilobular zone 3 necrosis or bile duct injury), or have variant features reminiscent of another disease (overlap syndrome). Corticosteroid therapy must be instituted early, applied despite the absence of symptoms, or modified in an individualized fashion. Pursuit of normal liver tests and tissue is the ideal treatment end point, but this objective must be tempered against the risk of side effects. Relapse after treatment withdrawal requires long-term maintenance therapy, preferably with azathioprine. Treatment failure or an incomplete response warrants salvage therapy that can include conventional medications in modified dose or empirical therapies with calcineurin inhibitors or mycophenolate mofetil. Liver transplantation supersedes empirical drug therapy in decompensated patients. Elderly and pregnant patients warrant treatment modifications. Difficult treatment decisions in autoimmune hepatitis can be simplified by recognizing its diverse manifestations and individualizing treatment, pursuing realistic goals, applying appropriate salvage regimens, and identifying problematic patients early.

Comparing the simplified and international autoimmune hepatitis group criteria in primary sclerosing cholangitis

BACKGROUND AND AIMS

Although highly sensitive and specific, the revised International Autoimmune Hepatitis Group (IAIHG) diagnostic criteria for autoimmune hepatitis (AIH) are cumbersome to use in clinical practice and rely upon a number of autoantibodies that are costly and are not widely available. The simplified scoring system for AIH attempts to rectify the complexity of the IAIHG criteria. To date, there have been few studies assessing the specificity of the simplified score for AIH when applied to patients with cholestatic liver diseases. The purpose of this study was to examine the specificity of the simplified scoring system for AIH as compared to the revised IAIHG criteria in a large cohort of patients with primary sclerosing cholangitis (PSC).

METHODS

The patient population consisted of 147 patients enrolled in two prospective trials at the Mayo Clinic examining the use of ursodeoxycholic acid in PSC. All of the patients underwent baseline blood work (including standard serologic testing to exclude other liver diseases), liver biopsy, and cholangiogram to confirm PSC. Demographic, laboratory, and histologic data were extracted for each subject. Simplified and revised IAIHG scores were calculated for each subject and compared.

RESULTS

The simplified scoring system identified 2 patients with probable AIH and no patients with definite AIH. Comparatively, the revised IAIHG scoring system identified no patients with probable or definite AIH.

CONCLUSION

As with the revised IAIHG criteria, the simplified scoring system for AIH has excellent specificity when applied to a PSC population.

Significance of antibodies to soluble liver antigen/liver pancreas: a large French study

BACKGROUND

Antibodies to soluble liver antigen (SLA)/liver pancreas (LP) are generally considered as highly specific diagnostic markers of type 1 auto-immune hepatitis (AIH-1), and are particularly useful in patients without conventional antibodies. However, the presence of anti-SLA/LP in type 2 auto-immune hepatitis (AIH-2), primary sclerosing cholangitis (PSC) and hepatitis C has recently been reported. The aim was thus to describe the characteristics of anti-SLA/LP-positive patients in the largest series reported to date.

METHODS

Sera were selected from the period between 1998 and 2005, based on the presence of antibodies to SLA/LP detected by two methods. The clinical status of patients was determined from their medical records.

RESULTS

Eighty-one anti-SLA/LP-positive patients with available clinical data were included: 89% (72/81) had a diagnosis of AIH-1, including 10 (12%) associated with cholestatic diseases (primary biliary cirrhosis in seven cases and PSC in three cases). Six patients (7%) suffered from another liver disease: hepatitis C (n=3) and drug-induced hepatitis (n=3). No specific diagnosis was made in three patients.

CONCLUSIONS

Antibodies to SLA/LP are of a major diagnostic value for AIH-1, including paediatric forms and overlap syndromes with cholestatic diseases, but are not found in association with anti-liver/kidney/microsome type 1 or antibodies to liver cytosol type 1. They are rarely present in other liver diseases such as hepatitis C and drug-induced hepatitis.

Seronegative autoimmune hepatitis presenting after diagnosis of coeliac disease: a case report

The relationship between liver dysfunction and coeliac disease is well established, ranging from transaminitis to chronic liver disease. In this report, we describe for the first time the development of a 'seronegative' autoimmune hepatitis in a teenager previously diagnosed with coeliac disease. He had normal liver function tests (LFTs) at diagnosis and was strictly compliant with a gluten-free diet. On screening blood tests at 1 year post diagnosis, he presented with raised LFTs leading to a diagnosis of autoimmune hepatitis on liver biopsy, successfully treated with mycophenolate mofetil. By using screening LFTs, we may well have prevented this patient from developing disease complications.

Overlap syndromes among autoimmune liver diseases

The three major immune disorders of the liver are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Variant forms of these diseases are generally called overlap syndromes, although there has been no standardized definition. Patients with overlap syndromes present with both hepatitic and cholestatic serum liver tests and have histological features of AIH and PBC or PSC. The AIH-PBC overlap syndrome is the most common form, affecting almost 10% of adults with AIH or PBC. Single cases of AIH and autoimmune cholangitis (AMA-negative PBC) overlap syndrome have also been reported. The AIH-PSC overlap syndrome is predominantly found in children, adolescents and young adults with AIH or PSC. Interestingly, transitions from one autoimmune to another have also been reported in a minority of patients, especially transitions from PBC to AIH-PBC overlap syndrome. Overlap syndromes show a progressive course towards liver cirrhosis and liver failure without treatment. Therapy for overlap syndromes is empiric, since controlled trials are not available in these rare disorders. Anticholestatic therapy with ursodeoxycholic acid is usually combined with immunosuppressive therapy with corticosteroids and/or azathioprine in both AIH-PBC and AIH-PSC overlap syndromes. In end-stage disease, liver transplantation is the treatment of choice.

Diagnosis and treatment of autoimmune hepatitis

Autoimmune hepatitis (AIH) is an idiopathic hepatitis characterized by inflammation of the liver, presence of autoantibodies, and evidence of increased gamma globulins in the serum. It represents an enigmatic interaction between the immune system, autoantigens, and unknown triggering factors. This article provides a brief summary of the diagnosis of AIH, the natural history of AIH, an approach to the treatment and follow-up of AIH, and the role of liver transplantation in the treatment of AIH.

Current topics relating to autoimmune hepatitis diagnosis and therapy

Autoimmune hepatitis (AIH) was first reported by Professor Ian R. Mackay. Environmental factors (such as viral infection), chemical substances (including some drugs) and genetic factors (such as human leukocyte antigen-DR) are believed to participate in the pathogenesis of AIH. Because satisfactory prognosis depends upon the patient being diagnosed with AIH correctly and receiving proper therapy immediately, it isvery important to make a correct diagnosis and perform the suitable therapy as soon as possible. In this review, current topics relating to AIH diagnosis and therapy are summarized.

The revised international autoimmune hepatitis score in chronic liver diseases including autoimmune hepatitis/overlap syndromes and autoimmune hepatitis with concurrent other liver disorders

BACKGROUND

We conducted a study in order to determine the usefulness and diagnostic value of International Autoimmune Hepatitis Group (IAHG) score in non-autoimmune hepatitis (AIH) hepatic disorders as well as in AIH/overlap syndromes and in cases with coexistence of AIH and other liver diseases.

METHODS

We applied the IAHG score in 423 patients with liver diseases excluding patients with AIH, AIH/overlap syndromes and AIH with concurrent other liver disease namely, patients with chronic hepatitis B (n = 109), chronic hepatitis C (n = 95), chronic hepatitis D (n = 4), alchoholic liver disease (n = 28), non-alcoholic fatty liver disease (n = 55), autoimmune cholestatic liver diseases (n = 77), liver disorders of undefined origin (n = 32) and with miscellaneous hepatic disorders (n = 23). 24 patients with AIH associated with any kind of liver disorder including 10 patients with AIH/overlap syndromes and 14 AIH with concurrent other liver disease were also investigated. 43 patients with AIH consisted the control group.

RESULTS

The specificity of the score was 98.1% while the sensitivity in unmasking AIH in patients with either AIH/overlap syndromes or AIH with concurrent other liver diseases was only 50% and 78.6%. In the binary logistic regression model, the presence of other autoimmune diseases (p < 0.001), the total histological score (p < 0.001) and positivity for autoantibodies (p < 0.05) were identified as independent predictors for the presnce of AIH/ovea syndromes o AI with concurren other liver diseass.

CONCLUSION

The IAHG scoring system has very good specificity for excluding AIH in patients with chronic liver diseases but not that sensitivity in order to unmask AIH/overlap syndromes or AIH with concurrent other liver diseases. The presence of other autoimmune diseases or autoantibody markers in the absence of hepatitis viral markers should alarm physicians for the possible presence of AIH either as "pure" AIH or in association with other liver disorders (AIH/overlap syndromes or AIH with concurrent other liver diseases). Under these conditions, liver histology seems essential and it must always be included in the work up of hepatic patients.

Autoimmune hepatitis: diagnosis, treatment, and prognosis

Autoimmune hepatitis (AIH) is an idiopathic hepatitis of unknown cause characterized by histologic evidence of chronic inflammation, liver autoantibodies, and increased gamma globulins in the serum. The clinical manifestations of AIH have been known since the 1950s and are essentially unchanged over the past 50 years. The cornerstone of therapy for AIH is immunosuppression using prednisone and azathioprine, with the vast majority of patients achieving clinical remission. This review provides a concise summary of the diagnostic criteria for AIH, describes its proposed pathogenic mechanisms and epidemiology, and offers an algorithmic approach to its initial treatment and follow-up.

Applicability of the IAIHG scoring system to the diagnosis of antimitochondrial/anti-M2 seropositive variant form of autoimmune hepatitis

BACKGROUND AND AIMS

According to the International Autoimmune Hepatitis Group (IAIHG) criteria, circulating antimitochondrial antibodies (AMA) do not support the diagnosis of autoimmune hepatitis (AIH). The aims of this study were to characterize a subset of patients with AIH who have AMA and antiM2 seropositivity, and to assess the applicability of the revised scoring system of the IAIHG in the diagnosis of this variant form of AIH.

METHODS

Eighteen patients with AMA-AIH were enrolled and compared with 206 classical AIH and 85 primary biliary cirrhosis (PBC) controls. Human leukocyte antigen (HLA) class II alleles were determined by polymerase chain reaction (PCR) amplification with sequence-specific primers, and biopsies were blindly reevaluated.

RESULTS

The patients with AMA-AIH were, on average, older than patients with classical AIH and had an hepatocellular pattern of elevated liver enzymes, hypergammaglobulinemia and lower levels of cholesterol, when compared with PBC controls. There were no histological signs of PBC or overlapping forms in any AMA-AIH biopsies. The majority of patients with AMA-AIH carried HLA antigens associated with classical AIH (DRB1*03, n = 5; DRB1*04, n = 7, and DRB1*13, n = 6). Pretreatment scores classified all AMA-AIH patients with probable (n = 17) or improbable (n = 1) AIH. After treatment, only 28% of AMA-AIH patients reached scores for definite diagnosis, compared with 90.1% of AIH-1 and 96.4 AIH-2. In the AMA-AIH group, only patients who relapsed after immunosuppressive drug withdrawal could be classified with definite AIH.

CONCLUSIONS

AMA-AIH shares common features with classical AIH. The diagnosis of AMA-AIH may be swayed by the IAIHG criteria, rendering questionable the applicability of the revised scoring system to this variant form of AIH.

Overlap syndromes of cholestatic liver diseases and auto-immune hepatitis

Approximately 18% of patients with auto-immune liver disease present with features characteristic of a second auto-immune liver disease. These cases have been termed "overlap syndromes."The pathogenesis of overlap syndromes is poorly understood, and few data are available regarding the clinical characteristics and outcome of this disease. Therefore, a consensus on the definition of overlap syndromes has not been reached. A common genetic background between auto-immune hepatitis (AIH) and its overlap with primary biliary cirrhosis(PBC) or primary sclerosing cholangitis (PSC) might confer susceptibility to a more inflammatory phenotype, probably requiring combined immunosuppressive treatment. This article focuses on the prevalence, diagnosis, and treatment of the overlap syndrome of AIH and PBC or PSC.

[Autoimmune hepatitis in a HIV-HCV co-infected patient: diagnostic ant therapeutic difficulties]

INTRODUCTION

Autoimmune hepatitis (AIH) is a chronic inflammatory hepatic disorder, characterized by hypergammaglobulinemia and autoantibodies. In some cases, AIH can be associated with another liver disease; such as the hepatitis C-AIH overlap syndrome, which diagnosis and treatment may be delicate.

EXEGESE

We report a type 1 AIH case in a HIV-HCV co-infected woman. AIH remission and HCV eradication were obtained with prednisone and interferon plus ribavirine. AIH relapse appeared with corticosteroid withdrawal and a new remission was obtained with immunosuppressive treatment associating prednisone and azathioprine, without opportunistic infection.

CONCLUSION

This case illustrates diagnostic and therapeutic difficulties of hepatitis C-AIH overlap syndromes in an HIV-infected patient. To our knowledge, it is the first AIH case report in a HIV-HCV co-infected patient.

Long term outcome and response to therapy of primary biliary cirrhosis-autoimmune hepatitis overlap syndrome

BACKGROUND/AIMS

Whether primary biliary cirrhosis (PBC)-autoimmune hepatitis (AIH) overlap syndrome requires immunosuppressive therapy in addition to ursodeoxycholic acid (UDCA) is a controversial issue.

METHODS

Seventeen patients with simultaneous form of strictly defined overlap were followed for 7.5 years. First-line treatment was UDCA alone (UDCA) in 11 and combination of immunosuppressors and UDCA (UDCA + IS) in 6.

RESULTS

Characteristics at presentation were not significantly different between the 2 groups. In the UDCA + IS group (f-up 7.3 years), biochemical response in terms of AIH features (ALT<2ULN and IgG < 16 g/L) was achieved in 4/6 and fibrosis did not progress. In the UDCA group, biochemical response was observed in three patients together with stable or decreased fibrosis (f-up 4.5 years) whereas the eight others were non-responders with increased fibrosis in four (f-up 1.6 years). Seven of these eight patients subsequently received combined therapy for 3 years. Biochemical response was obtained in 6/7 and no further increase of fibrosis was demonstrated. Overall, fibrosis progression in non-cirrhotic patients occurred more frequently under UDCA monotherapy (4/8) than under combined therapy (0/6) (P = 0.04).

CONCLUSIONS

Combination of UDCA and immunosuppressors appears to be the best therapeutic option for strictly defined PBC-AIH overlap syndrome.

MR Imaging Findings in Autoimmune Hepatitis: Correlation with Clinical Staging

PURPOSE

To retrospectively evaluate the morphologic and enhancement features of the liver on magnetic resonance (MR) images obtained in patients with autoimmune hepatitis (AIH) and to determine if there is a correlation between MR imaging findings and severity of clinical disease as measured with the Mayo end-stage liver disease (MELD) score.

MATERIALS AND METHODS

This study was compliant with the Health Insurance Portability and Accountability Act and approved by the institutional review board. The need for informed consent was waived. Thirty-two patients (29 female and three male patients; mean age, 44 years; age range, 14-69 years) undergoing treatment for AIH underwent unenhanced and gadolinium-enhanced MR imaging. Two radiologists reviewed all cases independently to determine the presence of patchy or heterogeneous liver enhancement, biliary duct changes, lymphadenopathy, and findings of portal hypertension. Fibrosis was graded as mild, moderate, or severe reticular (corresponding to a grading scale of 1-3) or as confluent. Agreement between radiologists was assessed by using kappa coefficients. Mean MELD scores were compared across fibrosis categories by using the Kruskal-Wallis analysis of variance.

RESULTS

Of the 32 patients, two (6%) had no imaging findings of cirrhosis. Thirty patients (94%) had reticular fibrosis with a mean grade of 1.8. Six patients had confluent fibrosis, and all six had associated reticular fibrosis. Mild intrahepatic biliary duct dilatation involving the right and left lobes was observed in four patients (12%). Lymphadenopathy was observed in 12% of patients. None of the patients had hepatocellular carcinoma. There was no significant overall association between fibrosis grade and MELD score (P = .36).

CONCLUSION

Although fibrosis is a common feature in AIH and is often moderate to severe, no significant correlation between fibrosis grade and MELD score was found.

Unnecessary repeat requesting of tests: an audit in a government hospital immunology laboratory

Unnecessary repeat requesting of tests can make up a large proportion of a laboratory's workload. This audit set out to establish the size of this problem and to identify the circumstances under which these repeat requests were made in a government tertiary hospital immunology laboratory. The numbers of tests for immunoglobulin measurement, common autoantibodies, and tumour markers that were repeated over a 12 month period were analysed by interrogating the Delphic laboratory computer system using a management information system for raw data enquiry protocol. Repeat requests within 12 weeks of a previous request made up 16.78% of the total workload. The total cost of the tests was estimated at 132 151 US dollars. The waste of technician time and reagents as a result of unnecessary repeat testing is excessive. Many of these tests might be eliminated with the use of interventions such as computerised reminders.

Viral diseases of the liver in children: diagnostic and differential diagnostic considerations

This review summarizes the general histologic features of acute and chronic hepatitides and highlights those morphologic findings that may suggest or be diagnostic of a specific agent or etiology. The main epidemiologic, clinical, and pathologic features of the hepatotropic viruses are discussed, with an emphasis on pediatric studies and the differential diagnosis of hepatitis in childhood.

Frequency and predictive factors for overlap syndrome between autoimmune hepatitis and primary cholestatic liver disease

OBJECTIVES

To evaluate the frequency of cholestatic pattern in patients with autoimmune hepatitis (AIH) and to identify predictive factors associated with the development of the overlap syndrome.

METHODS

Eighty-two consecutive patients diagnosed with AIH at the referral centre between January 1998 and June 2002 were included in the study. The new scoring system modified by the International Autoimmune Hepatitis Group was used to classify patients as definite/probable. Overlap syndrome was considered when the patient had clinical, serological and histological characteristics of two conditions: AIH and primary biliary cirrhosis (PBC) or AIH and primary sclerosing cholangitis (PSC).

RESULTS

From the 82 AIH patients (76 female and six male), 84.1% presented definite AIH (> 15 points) and 15.9% probable AIH (10 - 15 points). The frequency of the overlap syndrome was 20%: 13% with PBC and 7% with PSC. In the univariate analysis the overlap syndrome was associated with male gender (P = 0.01), age < 35 years (P < 0.0001), histopathological aspect of cholestasis (P < 0.0001), suboptimal response to treatment (P < 0.0001) and probable AIH (P < 0.0001). Age < 35 years, probable AIH and the absence of anti-nuclear antibody (ANA) have been identified as independent indicators of the overlap diagnosis by the logistic regression analysis.

CONCLUSION

Patients with overlap syndrome between AIH and primary cholestatic liver disease are frequently diagnosed in clinical practice, representing 20% of AIH cases in our study. The independent predictive factors associated with the diagnosis of overlap syndrome are young age, ANA(-) profile, and probable diagnosis according with the scoring system for AIH.

Chronic hepatitis in dogs: a review of current understanding of the aetiology, progression, and treatment

Chronic hepatitis is common in dogs in primary and referral practice but the cause is usually unknown. This paper reviews the literature on potential causes of chronic hepatitis in dogs (infectious, autoimmune, metabolic, toxic, and breed-associated) together with the literature on the progression of the disease and on treatments. This is compared with the current understanding of aetiology, progression, and treatment of chronic hepatitis in man. Unfortunately, little is known about the aetiology and progression of the canine disease and very few therapies have been subjected to critical trials. It is difficult therefore to draw conclusions about causes and effective treatment in dogs. Even the histological description for canine chronic hepatitis has yet to be standardised. Much research remains to be done and this review suggests some potential areas for future investigation.

Overlap syndromes of autoimmune hepatitis: what is known so far

The pattern of some autoimmune hepatitis can be difficult to classify, sometimes due to the overlap of these with primary biliary cirrhosis, primary sclerosing cholangitis and chronic viral hepatitis. The etiology of these variant forms remains unclear. The distinction among the overlap syndromes poses different problems both of prognosis and therapeutic approach. Presently, the utility of the scoring system devised and revised by the International Autoimmune Hepatitis Group regarding these cases is under discussion. Histological examination seems to be an important tool, but often the result does not help in defining a correct diagnosis. To date, the overlap syndromes can be classified at an intermediate level between cholestatic forms of autoimmune hepatitis or hepatic forms of cholestatic syndromes, but it cannot be excluded that the syndromes represent independent disorders.