How many types of autoimmune hepatitis are there?

Autoimmune hepatitis in Italy: the Bologna experience

BACKGROUND/AIMS

Autoimmune hepatitis affects mainly women. It is subdivided into type 1 and type 2 according to the autoantibody profile and without immunosuppression usually evolves to cirrhosis and end-stage liver failure.

METHODS

We evaluated clinical, biochemical, immunological and genetic features and treatment response of 163 consecutive Italian patients with autoimmune hepatitis.

RESULTS

At diagnosis, type 1 autoimmune hepatitis showed more inflamed liver histology and more pronounced cholestasis, whereas type 2 was more common in children. Male and female patients shared similar clinical, biochemical and immunological features. Of 89 patients with 5-year follow-up or longer, 23 patients irrespective of presenting clinical, biochemical and immunological features achieved complete remission (normal transaminases and gammaglobulin levels) which was maintained with minimal steroid dosage; attempt at treatment withdrawal led to disease exacerbation. Complete responders had more often HLA DRB1*0401 (p = 0.011) and their risk of disease progression was lower (p < 0.0001).

CONCLUSIONS

Type 1 and type 2 autoimmune hepatitis is one and the same disease. Autoimmune hepatitis has similar features in male and female patients. HLA DRB1*0401 positive patients are more likely to achieve complete remission. Continuous low-dose steroids are necessary to maintain remission, significantly reducing the risk of disease progression.

Autoimmune hepatitis: diagnostic criteria, subclassifications, and clinical features

The diagnosis of AIH depends on the finding of several suggestive features together with careful exclusion of liver diseases of other etiologies. Wherever possible, the diagnosis should be confirmed histologically by an experienced hepatopathologist. Seronegativity for the conventional autoantibodies at presentation does not exclude a diagnosis of AIH. It is important to test for anti-LKM1 antibodies to avoid missing a diagnosis of type 2 AIH, with potentially serious consequences. Although the syndrome is associated with characteristic biochemical abnormalities, and biochemical parameters are commonly used for monitoring response to therapy, it should be borne in mind that neither these nor autoantibody titers are completely reliable indices of disease activity. Although the various systems that have been promulgated for classification of the disease may identify different groups of patients on pathogenetic or clinical criteria and are useful for research purposes, none is yet sufficiently exclusive in terms of defining prognosis or planning treatment strategies to be applicable to the individual patient seen in the clinic. Clinical management should therefore continue to be individually tailored.

Clinical significance of autoantibodies to soluble liver antigen in autoimmune hepatitis

BACKGROUND/AIMS

Classification of autoimmune hepatitis (AIH) into different subgroups according to autoantibody status has been proposed: type I (ANA/SMA), type II (LKM-1) and type III (anti-SLA). However, whether type III AIH forms a clinically distinct disease entity remains controversial. The aim of this study was to evaluate the subclassification of AIH into ANA/SMA and anti-SLA positive patients with regard to clinical, biochemical and histologic differences.

METHODS

Ninety-seven consecutive patients with a well-documented long-term course of AIH with ANA/SMA and/or anti-SLA autoantibodies were studied. Clinical, biochemical and histological features of patients with ANA/SMA and/or anti-SLA autoantibodies were compared in a secondary analysis of data acquired prospectively.

RESULTS

Anti-SLA autoantibodies were found in 21.6% of patients. Anti-SLA-positive patients tended to have lower transaminases (mean: 153 vs. 247 IU/l), gamma-globulins (25 vs. 31%) and bilirubin (1.8 vs. 3.3 mg/dl) in comparison to ANA/SMA positive patients, but there was a large overlap. HLA-type A1 B8 was more frequent in anti-SLA positive patients, while there was no difference in HLA DR3 and DR4 allotype. Response to immunosuppressive therapy was excellent, but relapse occurred frequently. Diagnosis of anti-SLA positive AIH was often delayed (mean: 68 months from first elevation of transaminases) since testing for anti-SLA autoantibodies is currently not generally available.

CONCLUSIONS

ANA/SMA and anti-SLA positive patients share most clinical, biochemical, histologic and prognostic features. Distinction between type I and type III AIH is therefore clinically not helpful. However, testing for anti-SLA autoantibodies helps in the diagnosis of AIH in many patients who may otherwise be misdiagnosed.

Factors associated with progression of the disease before transplantation in patients with autoimmune hepatitis

AIMS/BACKGROUND

Studies on transplanted patients may provide clinically useful data on factors influencing progression of autoimmune hepatitis (AIH) since transplantation rather than death may now be considered as the most likely end-point of the disease. The aim of this work was to analyze risk factors related to progression of AIH before transplantation and provide guidelines for further prognostication with regards to the timing of transplantation.

METHODS

80 liver transplants in 68 patients with AIH were performed in our unit. The diagnosis was established on conventional clinical criteria. Parameters such as sex, age at diagnosis and transplantation or duration of the disease were evaluated in relation to: patient HLA DR status, disease presentation (aggressive or non-aggressive), presence of anti-LKM antibodies and concurrent immune disease.

RESULTS

AIH with concurrent immune disease occurred more commonly in females (90 vs. 61%; p = 0.0075) and was linked with markedly slower progression of the disease (125 vs. 66 mo; p = 0.002) as compared to subjects without such association. AIH without concurrent autoimmune disease occurred significantly more commonly in patients with DR3 phenotype (p = 0.01). Patients with positive anti-LKM autoantibodies were younger at transplantation (25.6 vs. 43.5 yr; p = 0.006) and had more rapid progression of their disease (14.3 vs. 103 mo; p = 0.001). Unlike previously reported series of non-transplanted patients, all anti-LKM positive subjects had no concurrent autoimmune disease.

CONCLUSIONS

Coincidence with another autoimmune disease is associated with a significantly longer disease history prior to transplantation and may possibly reflect greater responsiveness to immunosuppressive therapy before grafting. AIH without concurrent autoimmune disease, particularly if associated with DR4 negative phenotype, male sex and anti-LKM antibodies may characterize patients with rapid progression of the disease. None of these factors had a significant influence on 5 year survival after surgery.

Is severe cryptogenic chronic hepatitis similar to autoimmune hepatitis?

BACKGROUND/AIMS

It has been reported that severe cryptogenic chronic hepatitis may be a subgroup of autoimmune hepatitis. The aims of this study were to investigate the clinical features, liver function tests, human leukocyte antigens and response to immunosuppressive therapy in severe cryptogenic chronic hepatitis, and to compare the findings in such patients with those in patients with autoimmune hepatitis.

METHODS

History of alcohol and hepatotoxic drug intake, markers of metabolic liver disease, autoantibodies (antinuclear antibody, smooth muscle antibody, antibody to liver/kidney microsome type 1), and viral markers (HBsAg, HBV DNA, anti-HCV, HCV RNA) were negative in all severe cryptogenic chronic hepatitis patients (histological activity index > 9 and alanine aminotransferase level > 2 x normal). Fifteen cryptogenic patients (13 women; mean age, 33 +/- 16 years) and seven autoimmune patients (seven women; mean age, 28 +/- 3.9 years; five type 1; two type 2a) received prednisolone and azathioprine for at least 2 years.

RESULTS

Cryptogenic chronic hepatitis patients were similar to patients with autoimmune hepatitis with respect to age, sex, clinical presentation, liver function tests and Knodell scores at admission. HLA phenotype frequencies were comparable between cryptogenic and autoimmune groups: BW6 (77% vs. 100%), DR4 (62% vs. 57%), and HLA B8 (15% vs. 43%). The rates of complete and partial remissions achieved during therapy were 87% vs. 57% and 13% vs. 29%, respectively (p > 0.05).

CONCLUSIONS

The clinical, biochemical and HLA phenotypic features, and the responsiveness to immunosuppressive therapy in severe cryptogenic chronic hepatitis support the idea that it may be an autoimmune liver disease similar to autoimmune hepatitis.

Autoimmune hepatitis type 2 and hepatitis C virus infection: study of HLA antigens

BACKGROUND/AIMS

Markers for hepatitis C virus are often detectable in patients suffering chronic hepatitis with liver-kidney microsomal type 1 antibodies. Several authors have suggested that two subsets of those patients can be defined: a) hepatitis C virus negative and b) hepatitis C virus positive. The aim of this work was to further analyze the possible genetic association, HLA class I and II, in these two groups of patients.

METHODS

HLA was analyzed in 49 patients. Class I was studied using a standard lymphocytotoxicity test and in class II a reverse hybridization-based test for DRB1 typing and PCR-SSO for DQB1 typing were used. Sixty healthy Spanish subjects and 39 chronic hepatitis C subjects without anti-LKM1 antibodies were used as control groups for the "a" and "b" subsets, respectively.

RESULTS

No significant association was found with class I specificities in either group. DQB1 typing showed a very significant increase of DQ2 in the "a" group (93.3% vs. 48%; RR = 15; Pc = 0.0025), and DRB1 typing from the "b" group revealed a high association with DR7 (82.3% vs. 43.6%; RR = 6; Pc = 0.0086).

CONCLUSIONS

Our studies revealed a strong association with DQ2 for the "a" group and for the first time an extremely high association with DR7 antigen for the "b" subset. Hence it is possible to establish a different genetic profile in these two patient groups.

Nonhepatic manifestations and combined diseases in HCV infection

Infection with hepatitis C virus (HCV) may affect not only the liver but also various nonhepatic tissues and organs and may combine with many etiologically unrelated diseases and morbid conditions. Numerous nonhepatic manifestations in HCV infection have been previously reported. For some (eg, cryoglobulinemia), the association is well established. For others, such as sialadenitis and lichen planus, the association is probable (but not completely documented) and, for the remainder, the associations are weak. Extrahepatic manifestations may result from immunological mechanisms as well as virus invasion and replication in the affected extrahepatic tissues and organs. Thyroid abnormalities, primarily Hashimoto's disease, and isolated increases of anti-thyroid antibodies (ATPO) appear to be more frequent in chronic hepatitis C than B or D, with high ATPO titers clustering mainly among females. Interferon-alpha (IFN-alpha) therapy is associated with development of thyroid dysfunction in 5.5-12.9% of patients, usually exposing preexisting subclinical thyroid abnormalities. Mixed cryoglobulinemia (MC) is commonly found (36-45%) in patients with chronic HCV infection; however, only in a minority of cases does it become clinically manifested as systemic vasculitis with purpura, neuropathy, or Raynaud's phenomenon. In a number of patients, MC may terminate in non-Hodgkin's B-cell lymphoma. Treatment of these lymphoproliferative disorders with IFN-alpha is advocated. Idiopathic thrombocytopenia is now recognized more frequently in association with chronic HCV infection and is usually aggravated by IFN-alpha therapy. Patients with porphyria cutanea tarda (PCT) have demonstrated serological markers of HCV infection in 62-82% of cases. The usefulness of IFN-alpha in PCT remains to be demonstrated. Lichen planus has also been found in association with chronic HCV infection, particularly when severe or affecting the oral cavity. Other nonhepatic manifestations have also been reported in HCV infection such as diabetes, corneal ulceration, uveitis, and sialadenitis. These manifestations deserve further study and documentation. Finally, markers of autoimmunity occur with high frequency in chronic HCV infection; however, combination with the classical syndrome of autoimmune hepatitis is rare. In the presence of various autoantibodies, the clinical features of chronic hepatitis C do not appear to be modified and, contrary to general perception, IFN-alpha therapy within randomized controlled trials should not be withheld since the response rate to IFN-alpha does not appear to differ in the presence or absence of low titers of these markers.

Absence of anti-LKM-1 antibody in hepatitis C viral infection in the United States of America

Several studies from Europe have observed a relationship between hepatitis C virus infection and anti-liver/kidney microsome-1 (anti-LKM-1) positive chronic hepatitis. It has been suggested that hepatitis C may induce an autoimmune phenomenon that leads to the development of a specific type (type II anti-LKM-1 positive) autoimmune chronic hepatitis. We evaluated 204 sera from patients with well-documented hepatitis C infection from two centres in the United States of America and compared them with sera from 428 French patients from three centres. We evaluated the serological prevalence of anti-smooth muscle antibodies, anti-nuclear antibodies, anti-liver cytosol antibodies, and anti-mitochondrial antibodies subtype anti-M2 in patients with chronic hepatitis C. The two groups were matched in their ages, gender, mode of transmission of hepatitis C infection and severity of liver disease. Anti-LKM-1 was not observed in the patients from the USA at a time when it was noted in 3.7% of French patients. There were no differences, however, in the expression of other auto-antibodies, which were often in low titres. Absence of anti-LKM-1 in USA sera in comparison with French sera suggests that there may be differences in induction of anti-LKM-1 related to environmental and/or host genetic factors, and/or genomic variation in the hepatitis C virus.