Association of autoimmune hepatitis with HLA-Bw54 and DR4 in Japanese patients

Autoimmune Hepatitis: Epidemiology, Subtypes, and Presentation

Autoimmune hepatitis (AIH) is a chronic immunologic disorder in which the immune system targets the liver. The disease has a genetic basis and this accounts for the epidemiologic variation observed in serologic testing and clinical presentation across different populations. The incidence of AIH increases with age into the 70s and seems to be increasing in prevalence. Most patients test positive for antinuclear antibody, ASMA, or anti-LKM but about 20% of patients do not have these serologic markers. At clinical presentation, patients may be asymptomatic, symptomatic, have acute liver failure, or decompensated cirrhosis.

Impact of genetic and environmental factors on autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic non-resolving liver disease characterized by diffuse hypergammaglobulinemia, the presence of autoantibodies and characteristic histological findings. The disease can have catastrophic outcome with the development of end-stage liver disease if misdiagnosed/undiagnosed and left untreated. AIH pathogenesis remains obscure and the main hypothesis supports its development in genetically predisposed individuals after being exposed to certain environmental triggers. Genetic predisposition is linked to the presence of certain HLA alleles, mainly HLA-DR3 and HLA-DR4. However, a wide number of non-HLA epitopes have also been associated with the disease although data vary significantly among different ethnic groups. Therefore, it is likely that epigenetic alterations may also play a crucial role in disease's pathogenesis, although not yet extensively studied. The aim of this review was to summarize the genetic and environmental factors that have been associated with AIH, but also to open new insights towards the role of epigenetic modifications in the etiology of the disease.

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

BACKGROUND

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

Epigenetic changes and their implications in autoimmune hepatitis

BACKGROUND

The genetic risk of autoimmune hepatitis is insufficient to explain the observed risk, and epigenetic changes may explain disparities in disease occurrence in different populations within and between countries. The goal of this review was to examine how epigenetic changes induced by the environment or inherited as a phenotypic trait may affect autoimmune hepatitis and be amenable to therapeutic intervention.

MATERIALS AND METHODS

Pertinent abstracts were identified in PubMed by multiple search terms. The number of abstracts reviewed was 1689, and the number of full-length articles reviewed exceeded 150.

RESULTS

Activation of pro-inflammatory genes in autoimmune disease is associated with hypomethylation of deoxyribonucleic acid and modification of histones within chromatin. Organ-specific microribonucleic acids can silence genes by marking messenger ribonucleic acids for degradation, and they can promote inflammatory activity or immunosuppression. High circulating levels of the microribonucleic acids 21 and 122 have been demonstrated in autoimmune hepatitis, and they may increase production of pro-inflammatory cytokines. Microribonucleic acids are also essential for maintaining regulatory T cells. Drugs, pollutants, infections, diet and ageing can induce inheritable epigenetic changes favouring autoimmunity. Reversal is feasible by manipulating enzymes, transcription factors, gene-silencing molecules and toxic exposures or by administering methyl donors and correcting vitamin D deficiency. Gene targets, site specificity, efficacy and consequences are uncertain.

CONCLUSIONS

Potentially reversible epigenetic changes may affect the occurrence and outcome of autoimmune hepatitis, and investigations are warranted to determine the nature of these changes, key genomic targets, and feasible interventions and their consequences.

Autoimmune hepatitis: current challenges and future prospects

Autoimmune hepatitis (AIH) is a chronic progressive liver disease characterized by high levels of aminotransferases and autoantibodies, hypergammaglobulinemia, and interface hepatitis. AIH affects all races and all ages worldwide, regardless of sex, although a preponderance of females is a constant finding. The etiology of AIH has not been completely elucidated, but immunogenetic background and environmental parameters may contribute to its development. The most important genetic factor is human leukocyte antigens (HLAs), especially HLA-DR, whereas the role of environmental factors is not completely understood. Immunologically, disruption of the immune tolerance to autologous liver antigens may be a trigger of AIH. The diagnosis of classical AIH is fairly easy, though not without pitfalls. In contrast, the diagnosis of atypical AIH poses great challenges. There is confusion as to the definition of the disease entity and its boundaries in the diagnosis of overlap syndrome, drug-induced autoimmune hepatitis, and AIH with concomitant nonalcoholic fatty liver disease (NAFLD) or chronic hepatitis C. Centrilobular zonal necrosis is now included in the histological spectrum of AIH. However, the definition and the significance of AIH presenting with centrilobular zonal necrosis have not been examined extensively. In ~20% of AIH patients who are treated for the first time with standard therapy, remission is not achieved. The development of more effective and better tolerated novel therapies is an urgent need. In this review, we discuss the current challenges and the future prospects in relation to the diagnosis and treatment of AIH, which have been attracting considerable recent attention.

An analysis of drug-induced liver injury, which showed histological findings similar to autoimmune hepatitis

BACKGROUND

Drug-induced liver injury (DILI) sometimes resembles autoimmune hepatitis (AIH) in its hepatic histology. However, there is lacking data of a comparison of the characteristics between such DILI and DILI without histological findings like AIH.

METHODS

We enrolled 62 patients with DILI who were diagnosed using the Roussel Uclaf Causality Assessment Method, and performed a liver biopsy. These patients were classified into two groups: DILI with histology like AIH (group A, n = 23) and DILI without such histology (group B, n = 39). Sixteen patients of group A could be further classified into two groups: patients with relapse of the liver injury (group C, n = 8) and without relapse (group D, n = 8), after the recovery of the DILI. We compared the clinical and histological findings between group A and B, and group C versus D.

RESULTS

Group A was characterized by an older age (p = 0.043), higher immunoglobulin G level (p = 0.017), positive antinuclear antibody status (p = 0.044), and a higher frequency of complementary alternative medicines and Chinese herbal medicines as the causative drug (p = 0.008). There were no significant differences between group C and D regarding the clinical data and liver histological findings.

CONCLUSIONS

The clinical characteristics of DILI, which showed histological findings similar to AIH, were revealed. In such patients, a liver biopsy is recommended in order to determine the appropriate treatment strategy. In DILI with histology like AIH patients, long-term follow-up is needed to perceive the relapse.

Transitioning from Idiopathic to Explainable Autoimmune Hepatitis

Autoimmune hepatitis lacks an identifiable cause, and its diagnosis requires the exclusion of etiologically defined diseases that resemble it. Insights into its pathogenesis are moving autoimmune hepatitis from an idiopathic to explainable disease, and the goal of this review is to describe the insights that are hastening this transition. Two types of autoimmune hepatitis are justified by serological markers, but they also have distinctive genetic associations (DRB1 and DQB1 genes) and autoantigens. DRB1 alleles are the principal susceptibility factors in white adults, and a six amino acid sequence encoded in the antigen-binding groove of class II molecules of the major histocompatibility complex can influence the selection of autoantigens. Polymorphisms, including variants of SH2B3 and CARD10 genes, may affect immune reactivity and disease severity. The cytochrome mono-oxygenase, CYP2D6, is the autoantigen associated with type 2 autoimmune hepatitis, and it shares homologies with multiple viruses that might promote self-intolerance by molecular mimicry. Chemokines, especially CXCL9 and CXCL10, orchestrate the migration of effector cells to sites of injury and are associated with disease severity. Cells of the innate and adaptive immune responses promote tissue damage, and possible deficiencies in the number and function of regulatory T cells may facilitate the injurious process. Receptor-mediated apoptosis is the principal mechanism of hepatocyte loss, and cell-mediated and antibody-dependent mechanisms of cytotoxicity also contribute. Insights that explain autoimmune hepatitis will allow triggering exogenous antigens to be characterized, risk management to be improved, prognostic indices to be refined, and site-specific therapeutic interventions to emerge.

Autoimmune hepatitis in diverse ethnic populations and geographical regions

Autoimmune hepatitis has diverse clinical phenotypes and outcomes in ethnic groups within a country and between countries, and these differences may reflect genetic predispositions, indigenous etiological agents, pharmacogenomic mechanisms and socioeconomic reasons. In the USA, African-American patients have cirrhosis more commonly, treatment failure more frequently and higher mortality than white American patients. Survival is poorest in Asian-American patients. Autoimmune hepatitis in other countries is frequently associated with genetic predispositions that may favor susceptibility to indigenous etiological agents. Cholestatic features influence treatment response; acute-on-chronic liver disease increases mortality and socioeconomic and cultural factors affect prognosis. Ethnic-based deviations from classical phenotypes and the frequency of late-stage disease can complicate the diagnosis and management of autoimmune hepatitis in non-white populations.

Acute and acute severe (fulminant) autoimmune hepatitis

Autoimmune hepatitis frequently has an abrupt onset of symptoms, and it can present with acute liver failure. The abrupt presentation can indicate spontaneous exacerbation of a pre-existent chronic disease, newly created disease, a superimposed infectious or toxic injury, or new disease after viral infection, drug therapy, or liver transplantation. Deficiencies in the classical phenotype may include a low serum immunoglobulin G level and low or absent titers of the conventional autoantibodies. The original revised diagnostic scoring system of the International Autoimmune Hepatitis Group can guide the diagnostic evaluation, but low scores do not preclude the diagnosis. Liver tissue examination is valuable to exclude viral-related or drug-induced liver injury and support the diagnosis by demonstrating centrilobular necrosis (usually with interface hepatitis), lymphoplasmacytic infiltration, hepatocyte rosettes, and fibrosis. Conventional therapy with prednisone and azathioprine induces clinical and laboratory improvement in 68-75 % of patients with acute presentations, and high dose prednisone or prednisolone (preferred drug) is effective in 20-100 % of patients with acute severe (fulminant) presentations. Failure to improve or worsening of any clinical or laboratory feature within 2 weeks of treatment or worsening of a mathematical model of end-stage liver disease within 7 days justifies liver transplantation in acute liver failure. Liver transplantation for acute severe (fulminant) autoimmune hepatitis is as successful as liver transplantation for autoimmune hepatitis with a chronic presentation and other types of acute liver failure (patient survival >1 year, 80-94 %). Liver transplantation should not be delayed or superseded by protracted corticosteroid therapy or the empiric institution of nonstandard medications.

Living-donor liver transplantation for autoimmune hepatitis and autoimmune hepatitis-primary biliary cirrhosis overlap syndrome

AIM

  Recurrent autoimmune hepatitis (AIH) following liver transplantation has been reported in 20-30% of cases, mainly of Western populations. The aim of this study was to review our experience of living-donor liver transplantation (LDLT) in Japanese patients with AIH.

METHODS

  Among 375 adult (age ≥18 years) LDLT performed at our center between 1996 and 2010, 16 (4.2%) were for patients with AIH (n = 12) or AIH-primary biliary cirrhosis overlap syndrome (n = 4). The patient and donor characteristics and post-transplantation course were reviewed.

RESULTS

  All recipients were female with a median age of 48 years (range, 21-58). Low-dose methylprednisolone and calcineurin inhibitors were continued in all patients. Acute cellular rejection occurred in 10 (63%), which was more frequent than in our overall series of 28.5% (107/375 cases). Overall survival rate was 81.2% at 5 years. At the end of the follow up (median, 6.0 years [range, 0.1-9.6]), 13 patients were alive with normal liver function tests (aspartate transaminase, 18 ± 5 IU/mL; alanine transaminase, 16 ± 8 IU/mL). None of the survivors exhibited liver function test results suspicious for recurrent AIH, which might indicate liver biopsy.

CONCLUSION

  Survival after LDLT for AIH and overlap syndrome was excellent and there was no evidence of clinical recurrence. The recurrence rate of AIH after liver transplantation may differ among countries, and requires further investigation.

Long-term outcome of Japanese patients with type 1 autoimmune hepatitis

The long-term outcome of patients with autoimmune hepatitis (AIH) in Japan has not been well-defined. The aim of this study was to clarify the outcome of this disease over a long follow-up period compared with that of the general Japanese population as well as that among patients. A total of 203 AIH patients were enrolled for a mean follow-up period of 131 months. All patients were treated with corticosteroids with or without azathioprine. The overall survival of AIH patients was similar to that of the general population in Japan. The prognosis of AIH subgroups divided according to disease severity, sex, incidence of relapse, liver histology, presence of cirrhosis, probable or definite AIH score, antibody to hepatitis B core antigen antibody positivity, or human leukocyte antigen DR4-positivity did not differ greatly among patients. However, the prognosis of patients experiencing two or more relapses was significantly poorer than that of patients with remission or a single relapse both in univariate (P < 0.001) and multivariate (P = 0.020) analyses. The development of liver malignancy was also a possibility among AIH patients with multiple relapses. Severe adverse effects of corticosteroids were rare, even in patients who underwent long-term treatment.

CONCLUSION

Repeated relapses of AIH are significantly associated with a poorer long-term prognosis in Japan. AIH patients can expect a similar prognosis to that of the general population, provided they are adequately managed with continuous low doses of immunosuppressive therapy, especially after the first relapse.

Current trends in the diagnosis and treatment of autoimmune hepatitis in Japan

While a certain international consensus has been reached regarding the diagnosis and treatment of autoimmune hepatitis (AIH), there are some unique clinical characteristics of AIH in Japan. For diagnosis of AIH using the new simplified criteria proposed by the International Autoimmune Hepatitis Group, it is necessary to re-evaluate the antibody titer determined by using HEp-2 cells, which are widely used in Japan, and the finding of emperipolesis in liver histology, although the criteria are useful for rapid identification of AIH in routine clinical practice. The use of azathioprine as first-line therapy for AIH is limited in Japan because the drug is not covered by the Japanese national health insurance. Concomitant use of ursodeoxycholic acid (UDCA) to reduce corticosteroids and use of UDCA as monotherapy are therefore considered promising. Moreover, a relatively good survival rate has been reported in patients who developed AIH-induced acute liver failure and underwent living-donor liver transplantation. Current trends in the diagnosis and treatment of AIH in Japan are described in this report with a review of recent findings.

The impact of race/ethnicity on the clinical epidemiology of autoimmune hepatitis

GOALS

To evaluate race/ethnicity-specific variations in autoimmune hepatitis (AIH) with a focus on Asians and Hispanics, the fastest growing populations in the United States.

BACKGROUND

AIH is a chronic inflammatory disease in which race/ethnicity-specific variations in clinical epidemiology have been reported. However, earlier studies were small or did not include a comprehensive analysis of Asians and Hispanics, the 2 fastest growing population cohorts in the United States.

STUDY

A retrospective study analyzing patient data from 1999 to 2010 in a large tertiary-care community hospital to assess AIH epidemiology among a racially diverse population.

RESULTS

One hundred eighty-three patients with AIH were included in the study with 81 patients having "definite" AIH by International Autoimmune Hepatitis Group criteria and 63 were diagnosed with overlap syndromes. Women and whites were the largest cohorts. The average age of diagnosis was similar among all groups. Biopsy-confirmed cirrhosis was present in 34% of AIH patients with Hispanics demonstrating the highest prevalence of cirrhosis (55%). When compared with whites, Asians had higher international normalized ratio (INR) (1.4 U vs. 1.1 U, P<0.01), and Hispanics had lower serum albumin (3.3 g/dL vs. 3.7 g/dL, P<0.001) and platelets (123.8 thousand/mcL vs. 187.5 thousand/mcL, P<0.001) and higher international normalized ratio (1.5 U vs. 1.1 U, P=0.05). Kaplan-Meier survival analysis demonstrated a trend toward worse outcomes among Asians.

CONCLUSIONS

Among AIH patients, Hispanics had the highest prevalence of cirrhosis, and Asians had poorer survival outcomes. Race/ethnicity-specific disparities in AIH epidemiology may reflect underlying genetic differences, contributing to variations in disease severity, response to therapy, and overall mortality.

Characteristics of autoimmune hepatitis in the Asia-Pacific Region: historical review

BACKGROUND

Autoimmune hepatitis (AIH) has been considered a relatively rare disease in Asia, including Japan, where there is a high frequency of infection with hepatitis viruses.

METHOD

We reviewd the ethnic differences of clinical features of autoimmume hepatitis by reported paper.

RESULT

Immunogenetic predisposition, especially differences in human leukocyte antigens (HLAs), has been pointed out as one of the factors for the occurrence of AIH. In other words, HLA-DR3, which is the first disease-susceptibility gene for AIH discovered in UK and the USA, is extremely rare in Asia including Japan. Moreover, HLA-DR4, which is more frequent than HLA-DR3 in Asia, is associated with a favorable response to treatment and improved prognosis. This also explains why diagnosis and treatment of AIH have not drawn as much attention as viral hepatitis. However, as a survey conducted in Japan shows, the number of patients diagnosed with AIH is increasing. However, the number of elderly patients positive for HLA-DR4 is also increasing in UK and the USA.

CONCLUSION

In the era of genome-wide association studies, further progress of studies on AIH, a typical disease model for immunological liver cell damage, is expected.

Polymyositis associated with autoimmune hepatitis, primary biliary cirrhosis, and autoimmune thrombocytopenic purpura

We describe a 40-year-old woman with polymyositis (PM) who developed autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and autoimmune thrombocytopenic purpura (AITP) concurrently. About 4 years earlier, she suffered from muscle weakness probably due to PM. When she visited our hospital, she had polyarthritis, myalgia, symmetrical proximal limb-muscle weakness, elevated muscle enzymes, and myogenic abnormalities on electromyogram. Pathological findings obtained by muscle biopsy showed histological findings consistent with PM. Her serum liver enzymes were also elevated. The histology obtained by liver biopsy revealed the mixture findings of chronic active hepatitis and biliary cirrhosis. As antibodies to mitochondria M2 and liver/kidney microsome type 1 (LKM-1) were present, we concluded her liver disease was due to an overlap of AIH and PBC. Furthermore, purpura on the legs with thrombocytopenia appeared in parallel with liver dysfunction. She was diagnosed as having AITP by clinical and laboratory findings. Her serum showed a speckled pattern in immunofluorescence antinuclear antibody testing, but the antigen specificities were distinct from those of the known myositis-related autoantigens. This is a first case report of PM accompanied by AIH, PBC, and AITP. It was notable that there was an overlap of disease-associated immunological findings and immunogenetic backgrounds. This case provides a possible insight into the mechanisms and interplay of autoimmune diseases.

Genetic background of autoimmune hepatitis in Japan

Autoimmune hepatitis (AIH) is an organ-specific autoimmune disease characterized by chronic inflammation of the liver. Several studies from ethnically different countries have clarified that the genetic predisposition to type 1 AIH is linked mainly to human leukocyte antigen (HLA)-class II genes. Recently, molecular analysis using polymerase chain reaction (PCR)-based DNA typing has revealed that susceptibility to type 1 AIH is primarily associated with the HLA class II DRB1 locus, which encodes a polymorphic β chain of the HLA-DR antigen. However, additional susceptibility genes (either HLA or non-HLA) and/or environmental factors may also contribute to the development of type 1 AIH; in Japanese type 1 AIH patients, although the most influential gene in disease susceptibility is HLA-DRB1*04:05, several other genes have been identified as being involved in AIH pathogenesis or resistance and are the currently the focus of single nucleotide polymorphism analysis.

Clinical characteristics of patients with autoimmune hepatitis seropositive for anticentromere antibody

AIM

Recent studies have revealed that primary biliary cirrhosis patients with anticentromere antibody (ACA) commonly develop portal hypertension. However, the clinical characteristics of autoimmune hepatitis (AIH) remain uncertain. We investigated the clinical features of patients with AIH seropositive for ACA (ACA-AIH), comparing them with those of patients with AIH seropositive for other immunofluorescent patterns of antinuclear antibodies (ANA) (other-AIH).

METHODS

AIH was diagnosed on the basis of the scoring system proposed by the International Autoimmune Hepatitis Group. Seropositivity for ACA was determined by a discrete speckled pattern on HEp-2 cells by an immunofluorescent technique. The severity of histological grading and staging was evaluated by the histological activity index (HAI) score.

RESULTS

Eight (17%) of 47 patients with AIH had ACA. No significant differences in age, sex, onset pattern of the disease, progression to hepatic failure and relapse rate were present between the ACA-AIH and other-AIH groups. The frequency of concurrent autoimmune diseases in ACA-AIH was significantly higher than that in other-AIH (75% vs 36%, P = 0.0406). Biochemical analysis revealed a significantly lower mean immunoglobulin G (IgG) level than that in other-AIH (2176 +/- 641 vs 3013 +/- 923 mg/dL, P = 0.0150). However, there were no differences in serum alanine aminotransferase levels, titers of ANA, HAI scores or the positive rate of human leukocyte antigen (HLA)-DR4 between the groups.

CONCLUSION

These results suggest that the emergence of ACA is not a distinct entity of AIH, despite its clinical characteristics of a significantly higher frequency of concurrent autoimmune diseases and lower serum IgG levels.

HLA and autoimmune digestive disease: a clinically oriented review for gastroenterologists

OBJECTIVES

The human leukocyte antigen (HLA) system includes genes involved in graft-vs-host rejection and in immune response. The discovery that HLAs are associated with several diseases led to appealing developments both in basic biomedical research and in clinical medicine, and offered the opportunity to improve the understanding of pathogenesis and classification of diseases, as well as to provide diagnostic and prognostic indicators. The aim of this article is to review the association between HLA alleles and autoimmune digestive disease and its current relationship with modern HLA nomenclature and clinical practice.

METHODS

Articles dealing with the association between HLAs and autoimmune digestive disease (including celiac disease, inflammatory bowel disease, autoimmune hepatitis, sclerosing cholangitis and primary biliary cirrhosis) were searched for using Pubmed and SCOPUS databases from earliest records to January 2008.

RESULTS

The review has provided two sections. In the first, we explain the basic principles of HLA structure, function, and nomenclature, as an introduction to the second section, which describes current associations between HLA alleles and digestive diseases. The clinical implications of each HLA association are critically discussed. Actually, a clinical role for HLA typing is suggested for only a few conditions, e.g., celiac disease.

CONCLUSIONS

The knowledge of current HLA nomenclature and of its association with some digestive diseases such as celiac disease can be useful in clinical practice for diagnostic and prognostic purposes. This can avoid improper HLA typing as well as stressing the need for further studies on other possible clinical applications.

Favorable outcomes of autoimmune hepatitis in a community clinic setting

BACKGROUND AND AIM

Autoimmune hepatitis (AIH) is an idiopathic disease with diverse clinical manifestations. The aims of the present study were: (i) to describe the clinical characteristics of AIH patients in a community clinic setting; and (ii) to determine factors which were associated with poor clinical outcomes.

METHODS

A retrospective review was performed on 72 AIH patients who: (i) had pretreatment sera: (ii) were treatment-naïve at presentation; and (iii) had a minimum of 24 months of follow up.

RESULTS

On initial presentation, 22 (30%) had an acute onset of symptoms simulating acute viral hepatitis, 34 (47%) had chronic symptoms of greater than 6 months duration, and the remaining 16 (22%) were asymptomatic. Twenty-six (36%) had coexisting autoimmune diseases. Anti-nuclear antibody (ANA) was positive in 73% of the patients, and antismooth muscle antibody was positive in 15% of ANA-negative patients. Those few patients who tested positive for soluble liver antigen, anti-liver-kidney, microsomal antibody type-1, and anti-mitochondrial antibody were all also ANA positive. The median (range) duration of follow up was 98 (24-331) months. After immunosuppressive therapy, 26 of 72 (36%) remained in remission without further treatment. However, 46 (64%) required maintenance immunosuppression. Three patients who presented under the age of 20 years progressed to liver failure while on therapy and died while waiting for liver transplantation. Two other patients developed hepatocellular carcinoma (HCC) while on therapy and died.

CONCLUSIONS

A majority of AIH patients have an excellent prognosis. However, presentation at a younger age is a predictor of poor disease outcome and, although uncommon, HCC may develop during the late stages of cirrhosis.

Genetic factors affecting the occurrence, clinical phenotype, and outcome of autoimmune hepatitis

Autoimmune hepatitis is a polygenic disorder of unknown cause in which the genetic risk factors that affect occurrence, clinical phenotype, severity, and outcome still are being clarified. The susceptibility alleles in white North American and northern European patients reside on the DRB1 gene, and they are DRB1*0301 and DRB1*0401. These alleles encode a 6 amino acid sequence at positions 67-72 in the DRbeta polypeptide chain of the class II molecules of the major histocompatibility complex. This sequence is associated with susceptibility, and lysine at position DRbeta71 is the key determinant. Molecular mimicry between foreign and self-antigens may explain the loss of self-tolerance and the occurrence of concurrent immune diseases in anatomically distant organs. Disease severity is associated with the number of alleles encoding lysine at DRbeta71 (gene dose) and the number of polymorphisms, including those of the tumor necrosis factor-alpha gene, cytotoxic T lymphocyte antigen-4 gene, and tumor necrosis factor-receptor superfamily gene, that can modify the immune response. Individuals in different geographic regions may have different susceptibility alleles that reflect indigenous triggering antigens, and these may provide clues to the etiologic agent. Knowledge of the genetic predispositions for autoimmune hepatitis may elucidate pathogenic mechanisms, identify etiologic agents, characterize susceptible populations, foresee outcomes, and target new therapies. These lessons may be applicable to autoimmune disease in general.

Molecular therapy and prevention of liver diseases

Molecular analyses have become an integral part of biomedical research as well as clinical medicine. The definition of the molecular and genetic basis of many human diseases has led to a better understanding of their pathogenesis and has in addition offered new perspectives for their diagnosis, therapy and prevention. Genetically, liver diseases can be classified as hereditary monogenic, acquired monogenic, complex genetic and diseases. Based on this classification, gene therapy is based on six concepts: gene repair, gene substitution, cell therapy, block of gene expression or function, DNA vaccination as well as gene augmentation. While recent developments are promising, various delivery, targeting and safety issues need to be addressed before gene therapy will enter clinical practice. In the future, molecular diagnosis and therapy liver diseases will be part of our patient management and complement existing diagnostic, therapeutic and preventive strategies.

De novo autoimmune hepatitis following living-donor liver transplantation for primary biliary cirrhosis

Since first being described in 1998, de novo autoimmune hepatitis (AIH) after liver transplantation has been reported in several cases suffering from non-autoimmune liver diseases and primary biliary cirrhosis (PBC). Glutathione S-transferase (GST) T1 genotype mismatches between donor and recipient have also been suggested to constitute a risk factor for de novo AIH. Here, we report a 33-yr-old woman who presented complaining of marked fatigue and jaundice four yr after living-donor liver transplantation for PBC. On examination, transaminase levels were highly elevated and ANA and antimitochondrial antibody M2 were positive. Histological findings showed zonal necrosis with lymphoplasmacytic infiltration closely resembling AIH. She had pretreatment AIH score of 16 and 19 points after relapse of de novo AIH. Two color fluorescence in situ hybridization with X and Y chromosome-specific probes clearly revealed that the hepatocytes were of donor origin and lymphocytes were of patient origin. The GSTT1 genotype of the patient and the donor were the same null type, suggesting that mechanisms other than GSTT1 mismatches may exist in de novo AIH development. In conclusion, recipient immune cells attacked the allogeneic transplanted liver of the patient via de novo AIH, although the exact participation of autoimmune mechanisms is unclear.

Susceptibility to type 1 autoimmune hepatitis is associated with shared amino acid sequences at positions 70-74 of the HLA-DRB1 molecule

BACKGROUND/AIMS

The risk of developing autoimmune hepatitis (AIH) has been suggested to be associated with the presence of HLA-DRB1 alleles encoding the 'shared epitope' at amino acid positions 67-72 in the third hypervariable region (HVR3) of DRbeta. We aimed to identify the specific HLA alleles that are susceptible to type 1 AIH in Koreans, and to validate the shared epitope hypothesis in this single ethnic group.

METHODS

Sixty-two adult patients with definite type 1 AIH and 154 healthy controls were enrolled. Alleles of HLA class I and II genes were genotyped using sequence-based typing.

RESULTS

By high-resolution analysis, the frequencies of DRB1 *0405 and DQB1 *0401 were significantly increased in patients with AIH (P = 0.0001, OR = 3.74; P = 0.00006, OR = 3.95, respectively). The six amino acid motif represented by the single letter code LLEQRR or LLEQKR at positions 67-72 of the DRbeta polypeptide was not sufficient to show an increased risk for the disease. Interestingly, the QRRAA motif at positions 70-74 was significantly increased in Korean patients (P=0.04, OR=1.84).

CONCLUSIONS

The shared epitope hypothesis may be extended to the amino acid motif at positions 70-74 of HLA-DRbeta in order to better predict the susceptibility to type 1 AIH.

Genetic contribution of major histocompatibility complex class II region to type 1 autoimmune hepatitis susceptibility in Venezuela

AIMS

Autoimmune hepatitis (AIH) is a progressive liver disease characterized by the presence of circulating autoantibodies, hypergammaglobulinaemia and a favourable response to immunosuppressive treatment. Although the pathogenesis of type 1 AIH is unknown, disease susceptibility is partially determined by genes linked to the class II region of the major histocompatibility complex. Type 1 AIH has been associated with DRB1*03, DRB1*04 and DRB3 alleles in European and North American Caucasians, with DRB1*0405 in Japanese, with DRB1*0404 in Mexican, and with DRB1*1301 in Argentinean populations.

METHODS

To analyse the molecular basis of these associations in Venezuela (mestizo population), we examined the frequency of human leucocyte antigens (HLA)-A -B -C, HLA-DQ and HLA-DR genes by low- and high-resolution oligonucleotide typing in a population of 41 type 1 AIH patients and 111 ethnic- and aged-matched healthy subjects.

RESULTS

The frequencies of both DRB1(*)1301 (P<0.0001) and DRB1*0301 (P<0.005) were significantly higher in patients than in controls. In addition, patients showed a strong association with the DRB3 allele (P<0.01). In contrast, the DQB1*04 allele was significantly decreased in the patient group (P<0.01). The frequencies of haplotypes A*01-B*08-DQB1*02-DRB1*03-DRB3, DQB1*05-DRB1*1301, DQB1*06-DRB1*1301 and A*02-DRB1*1301, B*45-DRB3 were significantly increased in type 1 AIH patients compared with the controls (P<0.01).

CONCLUSIONS

In conclusion, our data indicate that type 1 AIH predisposition in a Venezuelan mestizo population of different ethnic backgrounds is associated with DRB1*1301 and DRB1*0301 alleles. In addition, our findings suggest that protection against disease might be conferred by the DQB1*04 allele, with distinct ethnic differences from other populations.

Lack of association between FCRL3 and FcγRII polymorphisms in Japanese type 1 autoimmune hepatitis

Autoimmune hepatitis (AIH) is an organ-specific autoimmune disease characterized by chronic inflammation of the liver. Although the HLA-DRB1*0405 allele is associated with type 1 AIH in Japanese, the exact genetic etiology of AIH remains undefined. Recently, polymorphisms of Fcgamma receptors (FcgammaR) and Fc receptor-like gene 3 (FCRL3) were linked to a variety of autoimmune diseases, and may be at least partially responsible for susceptibility to AIH. In this study, we genotyped FcgammaRIIA, FcgammaRIIB, and four FCRL3 polymorphisms in 87 Japanese patients with type 1 AIH and 97 ethnically matched controls using the TaqMan assay. Although we were able to detect significantly lower serum IgG concentrations in AIH patients specifically with the FCRL3-110A/A genotype, we observed no difference in the distribution of the genotypes between patients and controls, implying that susceptibility to type 1 AIH in Japanese patients is not influenced by FcgammaRIIA, FcgammaRIIB, or FCRL3 polymorphisms.

A genomewide DNA microsatellite association study of Japanese patients with autoimmune hepatitis type 1

Genetic predisposition to type 1 autoimmune hepatitis (AIH) is linked mainly to HLA class II genes. We previously searched the whole HLA region for AIH susceptibility genes using microsatellite markers and found only HLA-DR/DQ to be a candidate region for this suspected multifactorial disease. As such, the aim of this study was to broaden our search and screen the whole genome for additional genes that might contribute to type 1 AIH susceptibility. Eighty-one patients with type 1 AIH (15 men, 66 women, average age 55.9) and 80 healthy sex- and age-matched Japanese controls were enrolled in this study. We performed a case-control association study using 400 polymorphic microsatellite markers with an average spacing of 10.8 cM distributed throughout the whole genome. Two markers, one on chromosome 11 (D11S902, Pc = 0.013) and one on chromosome 18 (D18S464, Pc = 0.008), were revealed to have statistically significant associations with AIH. An additional 7 markers (D2S367, D6S309, D9S273, D11S1320, D16S423, D17S938, and D18S68) were also found to be candidate susceptibility regions. In addition, our results showed there were 17 regions that may contain genes of resistance to AIH. No specific markers were detected in HLA-DR4-negative patients, and no differences were seen in the clinical courses of patients (severe versus mild to moderate).

CONCLUSION

This first genomewide scan of Japanese AIH patients revealed at least 26 candidate AIH susceptibility or resistance regions other than HLA class II loci. These results also suggested that the products of several genes interact to determine heritable susceptibility to AIH.

Sarcoidosis accompanied by systemic lupus erythematosus and autoimmune hepatitis

A 52-year-old woman was admitted to our hospital for further examination of blurred vision, abnormal lung shadows and an elevated level of angiotensin-converting enzyme. Sarcoidosis was suspected, however, careful history taking revealed the existence of photosensitivity and polyarthralgia. Laboratory tests showed lymphocytopenia, liver dysfunction, hypergammaglobulinemia, and positive anti-nuclear, anti-double stranded DNA and anti-smooth muscle antibodies. Liver biopsy examination showed chronic active hepatitis. She was diagnosed with the triplex of sarcoidosis, systemic lupus erythematosus and autoimmune hepatitis. Marked improvement was noted after corticosteroid therapy.

Type 1 autoimmune hepatitis in Taiwan: diagnosis using the revised criteria of the International Autoimmune Hepatitis Group

Autoimmune hepatitis (AIH) is rare in Asian countries compared to the West, and an exceptionally low prevalence was noted previously in Taiwan. Using the revised criteria of the IAIHG, 48 cases of AIH patients were diagnosed. All patients were consecutively diagnosed over a period of 5 years. Detailed medical histories including disease onset, hepatitis B and C, alcohol, drugs, blood transfusion, and family history of autoimmune disease were recorded. Clinical manifestations, result of steroid therapy, outcome, and survival rate were investigated and analyzed. Clinical data on AIH patients with cirrhosis and without cirrhosis were compared and analyzed for their outcome. The statistical methods used were Fisher's exact test, Wilcoxon rank sum test, and Kaplan-Meier curve. Forty-eight patients were diagnosed as AIH type 1, with a median age of 58 years and a female:male ratio of 37:11. The most common clinical features at presentation were fatigue, jaundice, and anorexia. Ninety-eight percent of patients were ANA positive, and most of the patients showed elevated values of AST, ALT, serum globulin, and bilirubin. A substantial proportion of patients presented with poor liver function at entry and 35% of patients had liver cirrhosis, with relatively prolonged PT (P=0.001) and poorer outcome (P=0.005) compared to the noncirrhotics. As a whole there was a favorable treatment response and the overall survival rate was 85%. We conclude that the incidence of AIH in Taiwan is much higher than previously presumed and AIH type 1 is the predominant type of the disease. Although a substantial proportion of AIH patients presented with poor hepatic function at entry, as a whole there was a favorable clinical outcome.

A case of polyglandular autoimmune syndrome type III complicated with autoimmune hepatitis

A 58-year-old woman complaining of finger tremor was referred to our hospital. The diagnosis of Graves' disease was made based on increased free triiodothyronine (18.88 pg/ml) and free thyroxine (7.47 ng/dl), low TSH (<0.005 microIU/ml) and increased TSH receptor binding antibody activity (70.9%). Serum level of AST (62 U/l) and ALT (93 U/l) were increased and liver biopsy revealed linkage of adjacent portal areas by lymphoplasmacytic infiltrates and fibrosis with piecemeal necrosis. Although antinuclear antibody was negative, these findings indicated that she had autoimmune hepatitis (AIH) according to the criteria of the International Autoimmune Hepatitis Scoring System. Slowly progressive type 1 diabetes mellitus (DM) was confirmed by a diabetic response pattern due to 75 g-oral glucose tolerance test, and seropositivity towards anti-glutamic acid decarboxylase (725 U/ml) and islet cell (80 JDF Units) antibodies. This case exhibited an extremely rare combination of three different autoimmune diseases, including Graves' disease, slowly progressive type 1 DM and AIH, and had no known sensitive human leukocyte antigen (HLA) typing or haplotype for these disorders. Although it is common for patients with Graves' disease to exhibit abnormal liver function, it is important to make an accurate diagnosis of AIH because of this life-threatening disorder.

Distinctive clinical phenotype and treatment outcome of type 1 autoimmune hepatitis in the elderly

Autoimmune hepatitis is classically a disease of young women. Our aims were to determine its occurrence, clinical phenotype, and outcome in elderly patients and contrast findings to young adults. Two-hundred-and-five white North American adults with definite type 1 autoimmune hepatitis were grouped according to age at presentation and the groups compared. Forty-seven patients (23%) were aged > or = 60 years (median age, 68 years), and 31 patients (15%) were aged < or = 30 years (median age, 25 years). The patients > or = 60 years had a higher frequency of cirrhosis at presentation than the patients < or = 30 years (33% versus 10%, P = .03). They also had thyroid or rheumatic diseases more commonly (42% vs. 13%, P = .006). HLA DR3 occurred more frequently in the patients < or = 30 years than in those > or = 60 years (58% vs. 23%, P = .004), and HLA DR4 occurred more often in the patients > or = 60 years (47% vs. 13%, P = .003). Patients aged > or = 60 years failed corticosteroid treatment less commonly than those aged < or = 30 years (5% vs. 24%, P = .03). Autoimmune hepatitis occurred in patients aged 18-30 years (15%), 31-39 years (15%), 40-49 years (21%), 50-59 years (25%), and > or = 60 years (23%). Differences in age distribution, HLA frequencies, and treatment outcome occurred after age > or = 40 years. In conclusion, elderly patients have a greater frequency of cirrhosis at presentation and HLA DR4 than patients < or = 30 years, and they have a lower occurrence of treatment failure. Transitions in clinical and genetic phenotypes occur after age > or = 40 years. Genetic susceptibilities may favor etiologic factors that are age-related.

A murine model of acute liver injury induced by human monoclonal autoantibody

We have previously reported an immunoglobulin (Ig) M autoantibody to hepatocyte-related 190-kd molecules in patients with type 1 autoimmune hepatitis (AIH). This molecule was first isolated by hepatocyte-specific human monoclonal antibody (MoAb). To elucidate the role of this IgM autoantibody in hepatocyte injury, we examined the reactivity of this MoAb to murine hepatocytes and then questioned whether acute hepatic injury could be induced in mice via injection of this MoAb. The reactivity of MoAb was examined via both FACS analysis using murine hepatocytes and immunostaining of liver tissues. We then identified the murine hepatocyte membrane molecule recognized by this MoAb. The role of this MoAb in the immunopathogenesis of AIH was assessed by testing whether its injection into mice could increase serum aminotransferase levels as well as cause changes in liver histology. The present results demonstrate that this MoAb cross-reacted with murine hepatocytes and recognized a 190-kd molecule on the murine hepatocyte membrane just as in human hepatocytes. One hour after the injection of MoAb, the deposition of both IgM and complement component 3 was found in liver tissues. At 8 hours after the injection, serum aminotransferase levels were significantly increased in MoAb-injected mice compared with controls. Histological study revealed massive hepatocyte necrosis in MoAb-injected mice. In conclusion, human MoAb recognized a 190-kd molecule of both human and murine hepatocytes, and the injection of this MoAb to mice resulted in acute liver injury, indicating that this type of autoantibody may play an important role in the immunopathogenesis of AIH.

Fas polymorphisms influence susceptibility to autoimmune hepatitis

BACKGROUND AND AIMS

Genetic factors associated with autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC), immune-mediated chronic inflammatory liver diseases of unknown etiology, remain to be elucidated. Polymorphisms of the gene encoding Fas have been linked to a variety of autoimmune diseases. We hypothesized that Fas gene polymorphisms might be genetic markers for AIH and PBC.

METHODS

To determine the frequency and significance of Fas polymorphisms in patients with AIH and PBC, 74 Japanese AIH patients, 98 Japanese PBC patients, and 132 ethnically matched control subjects were investigated by the use of the Taqman assay.

RESULTS

We found significant differences between AIH patients and controls in allele frequencies of Fas-670 (p=0.009), Fas IVS (intervening sequence) 2nt176 (p=0.018), Fas IVS3nt46 (p=0.031), and Fas IVS5nt82 (p=0.013) polymorphisms. Haplotype analysis revealed that one of the haplotypes, GATGC, was associated with increased AIH prevalence. On the other hand, we found no statistically significant differences between PBC patients and controls in allele frequencies of the Fas polymorphisms genotyped in this study.

CONCLUSIONS

These results indicate a genetic link of Fas polymorphisms to the development of AIH. Further studies are needed to determine the genetic factors contributing to the development of AIH.

An unusual form of autoimmune hepatitis in young Somalian men

BACKGROUND

Significant diversity in disease severity has been identified for autoimmune disorders among different ethnic groups. Current knowledge of both the natural history and management of autoimmune hepatitis (AIH) has been derived from European or Japanese patients, and there is limited information about the disease in patients from other ethnic groups.

AIMS

To assess the clinical, histological and immunological features of AIH in patients from Somalia and to determine their response to therapy.

METHODS

Retrospective review of a cohort of young Somalian men with atypical AIH compared with a control group of European patients.

RESULTS

The six Somalian men were younger at presentation (median age 37 (range 24-59) years) than the seven female and three male European controls (55 (34-54) years, P = 0.06). The Somalians had slightly more severe disease at presentation-median modified Ishak stage of 2.5 compared with 2 in Europeans (P = 0.61) and four (66%) had features of cholestasis compared with only one (10%) European patient (P = 0.04). Therapy with prednisolone and azathioprine was completely effective for eight of 10 Europeans but only one of seven Somalians (P = 0.04). Analysis of human leucocyte antigen types revealed differences between the Somalian and European patients, although these differences did not reach statistical significance.

CONCLUSIONS

Somalian men with AIH present with cholestatic features and respond poorly to standard immunosuppressive regimes.

Genetic analysis of the HLA region of Japanese patients with type 1 autoimmune hepatitis

BACKGROUND/AIMS

Genetic predisposition to type 1 autoimmune hepatitis (AIH) is linked mainly to HLA-class II genes. The aim of this study is to scan the HLA region for additional genes which may contribute to type 1 AIH susceptibility.

METHODS

We performed association analysis using HLA class I and II alleles and 18 polymorphic microsatellite markers distributed throughout the HLA region. We specifically assessed tumor necrosis factor (TNF)-alpha gene polymorphisms.

RESULTS

The frequencies of HLA-DRB1*0405, DRB4 and DQB1*0401 alleles were significantly higher in AIH patients. The association study revealed the presence of three segments in the HLA region showing significantly low P (Pc) values. The first segment was located around the HLA-DR/-DQ subregion, the second was around the HLA-B54 allele, and the third was around two microsatellites near the TNF gene cluster. However, stratification analysis for the effect of DRB1*0405 eliminated association of the latter two segments. Haplotype D of the TNF-alpha promoter gene polymorphisms was weakly associated with susceptibility, but was found to be not significant after stratification analysis.

CONCLUSIONS

The most influential gene on type 1 AIH pathogenesis in Japanese is the HLA-DRB1. Other genes in the HLA region, including TNF-alpha, have little or no association with type 1 AIH susceptibility.

Genetic distinctions between autoimmune hepatitis in Italy and North America

AIM: Our goals were to analyze the known genetic predispositions for autoimmune hepatitis (AIH) in AIH Italian population and to compare them with North American counterparts.

METHODS: Human leukocyte antigens (HLA) B8, C7, DR3, DR4, DR7, DR11, DR13, DQ2 and the B8-DR3-DQ2 phenotype were determined by microlymphocytotoxicity and polymerase chain reaction in 74 Italian patients (57 with type 1 and 17 with type 2 AIH) and 149 North American patients with type 1 AIH, and in adequate controls.

RESULTS: B8-DR3-DQ2 occurred more frequently in Italian patients with type 1 AIH than in Italian controls (30% vs 7%, P<0.0001), but less frequently than in North American counterparts (30% vs 48%, P = 0.02). DR4 occurred less frequently in Italian patients with type 1 AIH (23% vs 43%, P = 0.01) and in controls (16% vs 34%, P = 0.0003) than in North American counterparts. No differences were found in alleles’ frequency between type 1 and type 2 Italian AIH patients. DR11 had a frequency lower in type 1 Italian AIH patients than controls (17% vs 35%, P = 0.01).

CONCLUSION: HLA DR4 is not associated with AIH in Italy. The known HLA risk factors for AIH occur similarly in Italian patients with type 1 and type 2 AIH, and they are less frequent than in North American patients. B8-DR3-DQ2 is the predominant phenotype of type 1 AIH also in Italy, and HLA DR11 may be a regionally distinctive protective factor against type 1 AIH.

Human leukocyte antigen allele associations in type-1 autoimmune hepatitis patients from western India

BACKGROUND AND AIMS

The immunogenetic basis of autoimmune diseases has become more and more evident. We have analyzed the human leukocyte antigen (HLA) associations with type-1 autoimmune hepatitis (AIH) among patients from western India.

METHODS

In 20 patients and 120 healthy controls, polymerase chain reaction amplified with sequence specific primers and hybridized with oligoprobes was carried out to elucidate the HLA A, B, C and DRB1 allele associations.

RESULTS

The study revealed that A*0222 (20% vs 1.66%; P = 0.0001), A*3201 (15% vs 0.83%; P = 0.0004), A*680102 (30% vs 6.66%; P = 0.001), B*35 (40% vs 11.66%; P = 0.001), B*5501 (10% vs 0.83%; P = 0.008), Cw*0102 (15% vs 1.66%; P = 0.002) and Cw*070101 (50% vs 11.66%; P = 2.5E-05) were significantly increased among the A, B and C alleles of AIH patients. Among the HLA DRB1 alleles, DRB1*0301 (20% vs 6.19%; P = 0.03), DRB1*1301 (15% vs 2.65%; P = 0.01), DRB1*14 (30% vs 11.5%; P = 0.02) and DRB1*1501 (40% vs 22.12%; P = 0.08) were increased in AIH patients when compared with the controls.

CONCLUSIONS

The present study indicates that the HLA susceptibility to type 1 AIH in the different populations studied is complex.

Clinical features and biochemical data of Caucasian children at diagnosis of autoimmune hepatitis

OBJECTIVE

Evaluation of systematic epidemiological data regarding clinical characteristics, sex distribution and autoantibody pattern in Caucasian children with autoimmune hepatitis (AIH).

STUDY DESIGN

Data of 142 children presenting with AIH (97 girls and 45 boys) have been analysed for their clinical, serological, and histological profile.

RESULTS

Clinical findings were jaundice (58%), unspecific weakness (57%), anorexia (47%), abdominal pain (38%) and paleness (26%). One hundred and three children (73%) (68 girls, 35 boys, 1.9:1) had AIH type 1 and 35 patients (25%) (27 girls, 8 boys, 3.4:1) type 2 due to specific autoantibodies. Four children could not be classified. Histology of 122 children revealed active hepatitis in 64 (52%), cirrhosis in 46 (38%), and mild inflammatory activity in 12 individuals (10%). The most prevalent HLA type was B8.

CONCLUSION

In our cohort the prevalence of AIH was half as frequent in boys as in girls. Type 1 was the most frequent diagnosis (73%) and was more prevalent in older children. Type 2 was equally age distributed. The clinical presentation of AIH in children was unspecific and type I and type II could only be differentiated by the determination of the specific autoantibodies. Ninety percent of patients presented with high inflammatory activity or liver cirrhosis.

Autoimmune hepatitis accompanied by systemic lupus erythematosus

We report a series of five patients with autoimmune hepatitis (AIH) accompanied by systemic lupus erythematosus (SLE) (AIH-SLE overlap). Serologic tests showed that all patients were positive for antinuclear antibody and double-stranded DNA antibody. Histological examination of the liver showed that three of the patients had chronic hepatitis with severe activity. One of the other two had acute and severe hepatitis with submassive necrosis in both portal and lobular areas. The last patient already had liver cirrhosis. All patients had a mild form of SLE and showed a rapid response to corticosteroid. There was no serious involvement of organs other than the liver in any of the patients, and the prognoses were comparatively good in all patients.

Epidemiology of autoimmune liver disease

Primary biliary cirrhosis (PBC), autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC) are chronic liver diseases that likely have an autoimmune basis to their pathogenesis. Although significant strides have been made in the clinical management of these conditions, their pathogenesis remains obscure. Understanding of various epidemiological factors may shed light on predisposing or causative factors for these diseases. Most is known about the epidemiology of PBC, with only minimal information on that of PSC and AIH. In this review, the current data on the epidemiology of PBC, AIH and PSC are summarized and suggestions are made for future work in this important area.

Individual and common antigen-recognition sites of liver-derived T cells in patients with autoimmune hepatitis

Autoimmune hepatitis (AIH) is characterized by dense T-cell infiltrations in the liver tissue, but little is known how T cells influence the pathogenesis. To address this question, the distribution of T-cell receptor variable beta-chain (TCR Vbeta) transcripts of peripheral blood and liver-infiltrating T cells from previously untreated patients with newly diagnosed acute exacerbated AIH was investigated. Furthermore, the lengths and sequences of complementary-determining region 3 (CDR3) were studied. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and CDR3 spectratyping revealed multiple clonal expansions of liver-infiltrating T cells but not peripheral T cells within various TCR Vbeta families. Further analysis of overexpressed TCR Vbeta transcripts using TCR beta-chain-joining element (TCR Jbeta)-specific primers in a nested PCR showed characteristic Vbeta/Jbeta combinations. Subsequent sequencing of CDR3 regions from PCR products confirmed the clonality of T-cell expansions and the usage of common and individual CDR3 motifs. In conclusion, the clonality of expanded T cells within the liver tissue during early clinical manifestation of untreated AIH indicated that autoantigen-specific T cells accumulate at the inflammation site. Individual and common CDR3 motifs argued for predominant epitopes that were recognized by liver-infiltrating T cells in AIH patients.

Clinical distinctions and pathogenic implications of type 1 autoimmune hepatitis in Brazil and the United States

BACKGROUND/AIMS

Type 1 autoimmune hepatitis has a strong genetic predisposition that varies among different ethnic groups. Our aims were to determine if the clinical manifestations differed between patients with type 1 autoimmune hepatitis from Brazil and the United States and if classical disease could be associated with region-specific susceptibility markers.

METHODS

The clinical manifestations and genetic risk factors of 161 patients from the United States were compared to those of 115 patients from Brazil.

RESULTS

The patients from Brazil had earlier disease onset, lower frequency of concurrent immune diseases, higher serum levels of aspartate aminotransferase and gamma-globulin, greater occurrence of smooth muscle antibodies, and lower frequency of antinuclear antibodies than the patients from the United States. Human leukocyte antigen (HLA) DR13 and DRB1*1301 occurred more commonly in the Brazilian patients and HLA DR4 less often. Normal subjects from each country had similar frequencies of HLA DR13 and DR3.

CONCLUSIONS

Type 1 autoimmune hepatitis in Brazil has different features at presentation than the disease in Caucasoid patients from the United States, and it is associated with HLA DR13. Background populations in each country have similar frequencies of HLA DR13 and DR3, and region-specific etiologic factors may determine the HLA association.

Treatment strategies in autoimmune hepatitis

Prednisone alone or a lower dose in combination with azathioprine is effective in improving symptoms, resolving laboratory and histologic features, and prolonging survival in patients with autoimmune hepatitis. The combination regimen of prednisone and azathioprine is preferred because of its lower frequency of corticosteroid-related side effects. Only patients with severe inflammatory activity have absolute indications for therapy. Treatment must be individualized in patients with mild-to-moderate disease. Medication should be continued at fixed daily maintenance levels until a remission, treatment failure, drug intolerance, or incomplete response has been established. Histologic examination before drug withdrawal ensures remission when symptoms and laboratory tests are normal or near normal. Treatment failure warrants high-dose therapy, whereas drug toxicity and incomplete response compel regimens that are modified individually according to response. Low-dose prednisone or indefinite azathioprine therapy are indicated in patients who have relapsed multiply. Empiric nonsteroidal treatments include ursodeoxycholic acid, cyclosporine, mycophenolate mofetil, and tacrolimus, and they have been used in limited studies to treat recalcitrant disease or corticosteroid intolerance. Investigational therapies promise to target critical pathogenic mechanisms affecting immunocyte activation, autoantigen recognition, cytokine interactions, and regenerative activity.

Type 1 autoimmune hepatitis in Turkish patients: absence of association with HLA B8

BACKGROUND

There is very little information about autoimmune hepatitis (AIH) in populations other than of white European or Japanese descent.

GOALS

To investigate the presenting features, immunogenetic background, and response to standard immunosuppressive therapy in native Turkish patients with AIH.

METHODS

Retrospective analysis of all patients referred between 1994 and 2000 to our hepatology clinic in Ankara who fulfilled international criteria for definite or probable type 1 or type 2 AIH.

RESULTS

Seventeen patients (15 female; median age, 31 years; range, 13-56 years) were identified. All had type 1 AIH. Clinical and laboratory features were broadly similar to those reported for white or Japanese patients. Five had the HLA DR3 allotype and 10 had DR4; however, in contrast to white and Japanese patients, DR4 was not associated with an older age at onset. Importantly, no patient had the B8 allotype (vs. 10.9% in 110 healthy Turkish subjects). Thus, none had the classic A1-B8-DR3 autoimmune haplotype: a major distinction from white individuals.

CONCLUSIONS

There appears to be genetic differences in type 1 AIH between Turkish and other populations. Genotyping of Turkish patients to identify alleles that may confer susceptibility or resistance to AIH may progress understanding of the genetic basis of the disease.

Prevalence and epidemiology of autoimmune hepatitis

The incidence and characteristics of AIH differ in various geographic regions. Based on limited epidemiologic studies, the incidence of type 1 AIH among Caucasoid populations of Europe and North America ranges from 0.1 to 1.9/100,000/year. The disease is considerably less frequent in Japan. The relative proportion of AIH among cases with chronic hepatitis is low in regions with a high prevalence of viral hepatitis. Type 2 AIH is more frequent in southern Europe than in northern Europe, the United States, and Japan. The occurrence of anti-SLA/LP is also higher in European than in Japanese patients with type 1 AIH. The frequency of HLA markers that affect susceptibility to AIH varies between ethnic groups. DRB1*0301 (DR3) and DRB1*0401 (DR4) are the major risk factors for type 1 AIH in white European and North American populations. DRB1*0405 (DR4) is the principal risk factor in Japanese and adult Argentine patients with type 1 AIH, and DRB1*0404 (DR4) is the main susceptibility allele in Mestizo Mexicans. Children may have different clinical manifestations than adults, and the diagnoses of type 2 AIH, autoimmune sclerosing cholangitis, and APS1 should be considered. Uniform application of diagnostic criteria formulated by the International Autoimmune Hepatitis Group should strengthen future epidemiologic studies and extend awareness of AIH to yet unstudied minority groups.

HLA DRB10405-DQB10401 haplotype is associated with autoimmune pancreatitis in the Japanese population

BACKGROUND & AIMS

Autoimmune pancreatitis is a distinctive disease entity characterized by high serum immunoglobulin G4 concentrations. Because of the close association between some autoimmune diseases and particular alleles of major histocompatibility complex genes, we investigated the association between HLA alleles and autoimmune pancreatitis.

METHODS

HLA-A, -B, -C, -DR, and -DQ gene typing and HLA-DRB1, -DQB1, and -DPB1 allele typing were performed by the polymerase chain reaction sequence-specific primers method and the restriction fragment length polymorphism method, respectively, in 40 patients with autoimmune pancreatitis, 43 patients with chronic calcifying pancreatitis, and 201 healthy subjects.

RESULTS

In patients with autoimmune pancreatitis compared with healthy subjects, we found a significant increase in DR4 (73% vs. 44%, corrected P = 0.01) and DRB1*0405 (58% vs. 21%, corrected P = 0.000026) and DQ4 (58% vs. 26%, corrected P = 0.001) and DQB1*0401 (58% vs. 21%, corrected P = 0.000017). The DRB1*0405-DQB1*0401 haplotype in autoimmune pancreatitis showed no significant association with any HLA class I antigens, in contrast to the B54-DRB1*0405-DQB1*0401 haplotype reported in autoimmune hepatitis. The frequencies of DRB1*0405 and DQB1*0401 were significantly high in patients with autoimmune pancreatitis compared with chronic calcifying pancreatitis.

CONCLUSIONS

It is probable that DRB1*0405-DQB1*0401 haplotype is associated with autoimmune pancreatitis in the Japanese population.

Characteristics of autoimmune hepatitis in patients who are not of European Caucasoid ethnic origin

BACKGROUND

Significant diversity in disease severity has been identified for autoimmune disorders among different ethnic groups but there is a lack of data on autoimmune hepatitis (AIH) in populations other than those of European Caucasoid (EC) or Japanese extraction.

AIMS

To assess the clinical features, response to therapy, and eventual outcome in AIH patients of non-EC ethnicity.

METHODS

A retrospective review of a regularly updated database of patients with AIH referred to liver outpatient clinics at King's College Hospital, London, since 1983.

RESULTS

Twelve patients were identified (10 female; six African, five Asian, one Arabic; median age at presentation 30 years (range 12-58)) who satisfied international criteria for type 1 (11 cases) or type 2 (one case) AIH. Nine (75%) had cholestatic serum biochemistry and three (25%) had mild biliary changes on liver biopsy without definitive features of primary biliary cirrhosis or cholangiographic evidence of primary sclerosing cholangitis. Four showed a complete biochemical response to standard prednisolone with or without azathioprine therapy, three partial, and five no response. Four have required liver transplantation for intractable disease. By comparison with 180 EC patients with definite AIH attending during the same period, the non-EC patients were younger (p<0.05), presented with cholestatic biochemistry (p=0.014), and morphological biliary features more frequently (p<0.0005) and showed a poorer initial response to standard therapy (p<0.0005).

CONCLUSIONS

Clinical expression of AIH in non-EC patients seems to differ in important respects from that in EC or Japanese patients. Management of such patients is challenging and may require alternative or more aggressive treatment strategies.

Current concepts in the diagnosis, pathogenesis, and treatment of autoimmune hepatitis

Autoimmune hepatitis has a global distribution and affects all ages. Genetic factors strongly influence susceptibility, clinical expression, and treatment response. The diagnosis of autoimmune hepatitis has been codified by an international panel. An acute or fulminant presentation is recognized but not a cholestatic form. Subclassifications by predominant autoantibody profile have been proposed, but they lack etiologic and prognostic differences. Autoantibodies continue to be characterized to improve diagnostic specificity, predict outcome, and identify pertinent antigenic targets. Cytosolic enzymes are prime candidates as autoantigens. DRB1*0301 and DRB1*0401 are the susceptibility alleles in Caucasoid Northern Europeans and North Americans, and they also affect clinical expression and treatment outcome. Other autoimmune promoters affecting cytokine production and immunocyte activation may act in synergy with the susceptibility alleles to affect disease behavior. Cell-mediated and antibody-dependent forms of cytotoxicity are probably interactive pathogenic mechanisms, and novel site-specific therapies are feasible because these mechanisms are defined. Potent new immunosuppressive agents are emerging from the transplantation arena, but prednisone alone or in combination with azathioprine remains the mainstay of treatment. Corticosteroid therapy is effective but not ideal.