Anti-smooth Muscle Autoantibodies Research Articles

Type 2 autoimmune hepatitis: Genetic susceptibility.

Two types of autoimmune hepatitis (AIH) are recognized; AIH-1 is characterized by the presence of anti-nuclear and/or anti-smooth muscle autoantibodies, while AIH-2 is associated with the presence of anti-Liver kidney microsome and/or anti-Liver Cytosol antibodies. The autoantigens targeted by AIH-2 autoantibodies are the cytochrome P450 2D6 and Formiminotransferase-cyclodeaminase for anti-LKM1 and anti-LC1 respectively. Both autoantigens are expressed in hepatocytes at higher levels than in any other cell type. Therefore, compared to AIH-1, the autoantigens targeted in AIH-2 are predominantly tissue-specific. Distinct clinical features are specific to AIH-2 compared to AIH-1, including diagnosis in younger patients (mean age 6.6 years), onset as fulminant hepatitis in very young patients (3 years of age or less), higher frequency in children than in adults and is frequently associated with extrahepatic T cell-mediated autoimmune diseases. AIH-2 is also often diagnosed in patients with primary immunodeficiency. AIH-2 is associated with specific HLA class II susceptibility alleles; DQB1*0201 is considered the main determinant of susceptibility while DRB1*07/DRB1*03 is associated with the type of autoantibody present. HLA DQB1*0201 is in strong linkage disequilibrium with both HLA DRB1*03 and DRB1*07. Interestingly, as in humans, MHC and non-MHC genes strongly influence the development of the disease in an animal model of AIH-2. Altogether, these findings suggest that AIH-2 incidence is likely dependent on specific genetic susceptibility factors combined with distinct environmental triggers.

Seamless Management of Juvenile Autoimmune Liver Disease: Long-Term Medical and Social Outcome

To report baseline features and long-term medical/social outcomes of juvenile autoimmune liver disease, including autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (ASC), managed in a single tertiary center. Retrospective study of children diagnosed in 2000-2004 with AIH/ASC followed up to date. Patients with abnormal cholangiogram were classified as ASC. Presentation and outcome features were compared. Eighty-three children were included (42 female, median age 12.1years [8.5-14.1years], AIH=54, ASC=29). Most (65%) had antinuclear and/or anti-smooth muscle autoantibodies; 6% presented with acute liver failure; 29% had histologic evidence of cirrhosis. The 1999 and simplified International Autoimmune Hepatitis Group criteria failed to diagnose up to 26% of patients with AIH and 48% with ASC, and the proposed the European Society for Pediatric Gastroenterology, Hepatology and Nutrition criteria were accurate. Response to treatment was excellent with 95% achieving normal transaminase levels. During follow-up, 31% had at least 1 relapse episode; 3 patients with AIH developed cholangiopathy and 5 patients with ASC developed progressive bile duct injury. At last follow-up (median of 14.5years, 10.4-16.8), 99% were alive, 11 underwent transplantation and 1 is listed for transplant. Five-, 10-, and 15-year transplant-free survival rates were 95%, 88%, and 83%; patients with ASC and those relapsing being more likely to require transplant. Social outcome was excellent with 93% in employment/education. Seamless management of juvenile autoimmune liver disease leads to excellent clinical and social outcomes. Despite good response to immunosuppressive treatment, patients with ASC have a worse prognosis than those with AIH. Diagnostic models developed for adults are unsatisfactory to correctly diagnose juvenile autoimmune liver disease.

A comprehensive autoantigen-ome of autoimmune liver diseases identified from dermatan sulfate affinity enrichment of liver tissue proteins

BackgroundAutoimmune diseases result from aberrant immune attacks by the body itself. It is mysterious how autoantigens, a large cohort of seemingly unconnected molecules expressed in different parts of the body, can induce similar autoimmune responses. We have previously found that dermatan sulfate (DS) can form complexes with molecules of apoptotic cells and stimulate autoreactive CD5+ B cells to produce autoantibodies. Hence, autoantigenic molecules share a unique biochemical property in their affinity to DS. This study sought to further test this uniform principle of autoantigenicity.ResultsProteomes were extracted from freshly collected mouse livers. They were loaded onto columns packed with DS-Sepharose resins. Proteins were eluted with step gradients of increasing salt strength. Proteins that bound to DS with weak, moderate, or strong affinity were eluted with 0.4, 0.6, and 1.0 M NaCl, respectively. After desalting, trypsin digestion, and gel electrophoresis, proteins were sequenced by mass spectrometry. To validate whether these proteins have been previously identified as autoantigens, an extensive literature search was conducted using the protein name or its alternative names as keywords. Of the 41 proteins identified from the strong DS-affinity fraction, 33 (80%) were verified autoantigens. Of the 46 proteins with moderate DS-affinity, 27 (59%) were verified autoantigens. Of the 125 proteins with weak DS-affinity, 44 (35%) were known autoantigens. Strikingly, these autoantigens fell into the classical autoantibody categories of autoimmune liver diseases: ANA (anti-nuclear autoantibodies), SMA (anti-smooth muscle autoantibodies), AMA (anti-mitochondrial autoantibodies), and LKM (liver-kidney microsomal autoantigens).ConclusionsThis study of DS-affinity enrichment of liver proteins establishes a comprehensive autoantigen-ome for autoimmune liver diseases, yielding 104 verified and 108 potential autoantigens. The liver autoantigen-ome sheds light on the molecular origins of autoimmune liver diseases and further supports the notion of a unifying biochemical principle of autoantigenicity.

Autoimmune Hepatitis in Children: The Current State of the Problem

Aim.To generalize the results of existing research studies carried out to investigate autoimmune hepatitis (AIH) in children, and the contemporary approaches to the diagnosis and therapy of the disease. Key points. According to the results of serological studies, two types of AIH can be distinguished in children. AIH of type 1 is diagnosed, when anti-smooth muscle autoantibodies (ASMA) and/or antinuclear autoantibodies (ANA) have been detected. AIH of type 2 AIH is diagnosed, when liver kidney microsomal autoantibodies (anti-LKM-1) and/ or anti-liver cytosolic autoantibodies (anti-LC-1) have been detected. Liver parenchymal inflammation responds well to a standard immunosuppressive therapy with prednisolone and azathioprine. Disease relapses are observed in about 40% of patients during treatment. It is expedient to treat children at least for 2–3 years before attempting to cancel the treatment, which decision should be considered only when the levels of transaminases have remained normal and IgG has been negative, or autoantibody titers have been low (1:20 using immunofluorescence method) for at least a year. Before attempting to cancel the therapy, liver biopsy and histological study should be repeated in order to exclude the possibility of residual inflammatory changes. For a small number of patients, who do not respond to standard treatment and those who suffer from frequent disease relapses, it is advisable to offer an alternative immunosuppressive treatment, the effectiveness of which is still ambiguous and poorly understood (including, in order of priority, mycophenolate mofetil, calcineurin inhibitors, rituximab, Inhibitor of tumor necrosis factor-alpha). In cases of refractoriness to therapy and the disease progression to liver cirrhosis and its decompensation, liver transplantation is justified. It is shown that AIH might relapse after liver transplantation. De novo AIH develops after liver transplantation as a result of non-autoimmune diseases; it is characterized by the presence of autoantibodies (ANA, ASMA and typical or atypical anti-LKM-1), and histologically characterized by a pattern similar to that of AIH. De novo AIH after liver transplantation responds well to a classical immunosuppressive therapy, but not to a standard antiretroviral therapy. In the review, we discuss issues associated with the clinical manifestations and diagnosis of AIH in children. Approaches to the treatment and long-term observation of such children are reviewed, including, i.e., those formulated by the main group of the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) members.Conclusion. Autoimmune hepatitis (AIH) in children has a progressive course with the outcome to liver cirrhosis. The presented review has summarized approaches to the diagnosis and selection of AIH therapy in children.

Treatment of Acute Liver Failure in Resource-Constrained Settings without Transplantation Facilities Can Be Improved.

Treatment of Acute Liver Failure in Resource-Constrained Settings without Transplantation Facilities Can Be Improved.

A novel "humanized mouse" model for autoimmune hepatitis and the association of gut microbiota with liver inflammation.

Autoimmune hepatitis (AIH) in humans is a severe inflammatory liver disease characterized by interface hepatitis, the presence of circulating autoantibodies, and hyper-gammaglobulinemia. There are two types of AIH, type 1 (AIH-1) and type 2 (AIH-2), characterized by distinct autoimmune serology. Patients with AIH-1 are positive for anti-smooth muscle and/or antinuclear autoantibodies, whereas patients with AIH-2 have anti-liver kidney microsomal type 1 and/or anti-liver cytosol type 1 autoantibodies. Cytochrome P4502D6 is the antigenic target of anti-liver kidney microsomal type 1, and formiminotransferase cyclodeaminase is the antigenic target of anti-liver cytosol type 1. It is known that AIH, both types 1 and 2, is strongly linked to the human leukocyte antigen (HLA) alleles -DR3, -DR4, and -DR7. However, direct evidence of the association of HLA with AIH is lacking. We developed a novel mouse model of AIH using the HLA-DR3 transgenic mouse on the nonobese-diabetic background by immunization of HLA-DR3- and HLA-DR3+ nonobese-diabetic mice with a DNA plasmid, coding for human cytochrome P4502D6/formiminotransferase cyclodeaminase fusion protein. Immunization with cytochrome P4502D6/formiminotransferase cyclodeaminase leads to a sustained elevation of alanine aminotransferase, development of antinuclear autoantibodies and anti-liver kidney microsomal type 1/anti-liver cytosol type 1 autoantibodies, chronic immune cell infiltration, and parenchymal fibrosis on liver histology in HLA-DR3+ mice. Immunized mice also showed an enhanced T helper 1 immune response and paucity of the frequency of regulatory T cells in the liver. Moreover, HLA-DR3+ mice with exacerbated AIH showed reduced diversity and total load of gut bacteria. Our humanized animal model has provided a novel experimental tool to further elucidate the pathogenesis of AIH and to evaluate the efficacy and safety of immunoregulatory therapeutic interventions in vivo.

Diagnostic Performance of an Anti-Actin Autoantibody Binding Enzyme Immunodot Blot in Autoimmune Hepatitis Type 1.

A serologic hallmark of autoimmune hepatitis (AIH) type 1 are anti-smooth muscle autoantibodies (ASMA) with specificity for filamentous actin (F-actin; AAA (anti-actin antibodies)), traditionally detected by indirect immunofluorescence (IFT) using rat liver, kidney, and stomach tissue sections as substrates. However, IFT is a subjective method requiring an experienced investigator. Therefore, a more objective technique for the detection of AAA may be a helpful diagnostic tool. In a retrospective study with cross-sectional design, we evaluated AAA detected by an enzyme immunodot blot (IDB; Liver5 IgG BlueDot, D-tek, Mons, Belgium). Serum samples of patients with AIH type 1 (n = 47) and specified controls (n = 142) were included. For comparison, standard IFT was applied to rat LKS (liver, kidney, stomach) triple tissue sections. IDB readings were done by two independent investigators (92% concordance). The diagnostic sensitivity of the AAA-IDB was 70%, compared to 51% of AAA-IFT (n.s.). The diagnostic specificity of AAA-IDB was significantly lower compared to AAA-IFT (76% vs. 94%; P < 0.0005). Correspondingly, the positive predictive value (49% vs. 75%; P < 0.05) and positive likelihood ratio (2.9 vs. 8.5) differed significantly. Neither prescreening for ANA or ASMA, nor the exclusion of infectious hepatopathies resulted in a significantly better diagnostic performance of the IDB. Compared to standard IFT, testing for AAA via IDB did not result in a significantly better diagnostic performance for AIH type 1. A blot with higher antigen binding specificity may be more functional.

The PTPN22 1858T allele but not variants in the proximal promoter region ofIL-21gene is associated with the susceptibility to type 1 diabetes and the presence of autoantibodies in a Brazilian cohort

Interleukin (IL)-21 and protein tyrosine phosphatase non-receptor 22 (PTPN22) regulate lymphocyte function and have been implicated in the pathogenesis of autoimmune diabetes. We sequenced the proximal promoter of the IL-21 gene for the first time and analysed the PTPN22 1858T polymorphism in type 1A diabetes (T1AD) patients and healthy controls (HC). We correlated the frequencies of islet and extra-pancreatic autoantibodies with genotypes from both loci. The case series comprised 612 T1AD patients and 792 HC. Genotyping of PTPN22 C1858T was performed on 434 T1AD patients and 689 HC. The -448 to +83 base pairs (bp) region of the IL-21 gene was sequenced in 309 Brazilian T1AD and 189 HC subjects. We also evaluated human leucocyte antigen (HLA) DR3/DR4 alleles. The frequencies of glutamic acid decarboxylase (GAD65), tyrosine phosphatase-like protein (IA)-2, anti-nuclear antibody (ANA), thyroid peroxidase (TPO), thyroglobulin (TG), thyrotrophin receptor autoantibody (TRAb), anti-smooth muscle (ASM) and 21-hydroxylase (21-OH) autoantibodies were higher in T1AD patients than in HC. The PTPN22 1858T allele was associated with an increased risk for developing T1AD [odds ratio (OR) = 1·94; P < 0·001], particularly in patients of European ancestry, and with a higher frequency of GAD65 and TG autoantibodies. HLA-DR3/DR4 alleles predominated in T1AD patients. A heterozygous allelic IL-21 gene variant (g.-241 T > A) was found in only one patient. In conclusion, only PTPN22 C1858T polymorphism and HLA-DR3 and/or DR4 alleles, but not allelic variants in the 5'-proximal region of the IL-21 gene were associated with T1AD risk. Patients with T1AD had increased frequencies of anti-islet-cell, anti-thyroid, anti-nuclear, anti-smooth muscle and anti-21-OH autoantibodies. The C1858T PTPN22 polymorphism was also associated with a higher frequency of GAD65 and TG autoantibodies.

A Case of Drug Induced Liver Injury

Purpose: INTRODUCTION: Drug induced liver injury (DILI) generally causes elevations of alanine aminotransaminase (ALT) levels and obstructive hepatobiliary disease usually causes elevation of alkaline phosphates (ALP) and gamma-glutamyltransferase (GGT). We present a case of DILI with abnormal ALP & GGT levels. CASE REPORT: An 88-year-old white female with medical history significant for HTN, CAD, hyperlipidemia and breast cancer was admitted to the psychiatric ward with major depression. She had a mastectomy 5 years ago and was taking anastrozole daily; an aromatase inhibitor used as adjuvant hormonal therapy in postmenopausal women with hormone receptor-positive breast cancer. Her other medications were metoprolol, enalapril, pravastatin, aspirin, clopidogrel and alendronate. She was not on any natural or herbal supplements. Physical examination was normal except for a mastectomy scar. Laboratory testing revealed abnormal liver function tests (LFT's): total bilirubin of 1.3 mg/dl, ALP of 509 iu/l, GGT of 1578 iu/l, ALT of 167 iu/l and aspartate aminotransaminase (AST) of 159 iu/l. CBC, PT/INR, viral hepatitis panel, autoimmune antibodies (including anti-mitochondrial and anti-smooth muscle autoantibodies), tumor markers (alpha-fetoprotein, CA 19-9, CEA, CA 27-29, CA 15-3) and imaging studies (abdominal sonogram and MRI) were unremarkable. A review of her records revealed that she had normal LFT's two months prior to admission. Patient was successfully treated for her mood disorder with mirtazapine and the anastrozole was discontinued. On repeat testing the LFT's showed improvement. She was advised to follow up with her oncologist and discuss alternative treatment. DISCUSSION: In our patient obstructive, viral and autoimmune causes of hepatitis were excluded out and DILI was thought to be the most likely cause. Among the patient's medications, anastrozole & pravastatin were likely causes for DILI. While pravastatin only affects transaminases, anastrozole can cause elevations of ALT, AST, ALP and rarely GGT. DILI can present with cytolytic, cholestatic or mixed patterns. Cytolytic damage usually occurs after a brief drug exposure whereas cholestasis is idiosyncratic and can occur after a prolonged latency period. Our patient had a prolonged latency period and presented with cholestatsis. Given the latency period, we suspect that anastrozole induced the translation of greater amounts of ALP & GGT. We believe that anastrozole could therefore be a novel inducer of cholestatic liver enzymes similar to that seen with phenytoin, barbiturates, rifampin and St. John's Wort. Further studies are needed to confirm this theory. We suggest that LFT's should be closely monitored in patients on anastrozole.

Drug rash with eosinophilia and systemic signs syndrome in a patient with multiple sclerosis

Introduction: Drug rash with eosinophilia and systemic signs (DRESS) syndrome is defined by the triad of fever, dermatitis, and internal organ involvement, characteristically occurring with a delay of 3 to 8 weeks after the initiation of treatment with the associated drug. We describe a case of DRESS syndrome in a patient with multiple sclerosis (MS), characterized by a very high eosinophilia and cholestatic hepatitis. Case summary: A 44-year-old white woman with primary progressive MS receiving a multidrug of PO baclofen 75 mg/d, PO piracetam 3 g/d, and IV mitoxantrone 10 mg administered once a month presented to the Multiple Sclerosis Center, University of Catania, Catania, Italy. Eight weeks after the introduction of the latter 2 drugs, the patient had clinical and histological signs of severe cholestatic syndrome followed by hypereosinophilia. All treatments were stopped on admission. Laboratory tests (serologic viral markers, autoantibody pattern antinuclear autoantibodies, antismooth muscle autoantibodies, antimitochondrial autoantibodies, antineutrophil-cytoplasmic autoantibodies, antiliver-kidney-microsomes), abdomen ultrasound, and magnetic resonance cholangiopancreatography did not reveal a cause of the cholestatic syndrome. A liver biopsy was performed because of the persistence of the clinical signs. A Naranjo rating of 4 suggested that mitoxantrone was possibly associated with the occurrence of DRESS. Six months after the first symptoms of DRESS appeared, laboratory tests were normal. Although there are few diagnostic methods for confirming an adverse drug hypersensitivity reaction, a skin prick test suggested a marked positivity for mitoxantrone at all concentrations (100%, 50%, 10%). During the first 72 hours, reaction was characterized by skin edema, erythema, and itchiness in the site of inoculation of the drug. The local reaction started to regress after 72 hours, with a complete restitution ad integrum in 6 days. A blue discoloration of skin remained for an additional 13 days. Conclusion: We report a case of DRESS syndrome possibly associated with mitoxantrone in a patient with MS.

Drug-induced hepatitis superimposed on the presence of anti-SLA antibody: a case report

IntroductionAutoimmune hepatitis is a necroinflammatory disorder of unknown etiology characterized by the presence of circulating antibodies, hypergammaglobulinemia, and response to immunosuppression. It has the histological features of chronic hepatitis. The onset is usually insidious, but in some patients the presentation may be acute and occasionally severe. Certain drugs can induce chronic hepatitis mimicking autoimmune hepatitis. Different autoantibodies have been associated with this process but they are not detectable after drug withdrawal and clinical resolution.Case presentationWe describe a case of drug-induced acute hepatitis associated with antinuclear, antisoluble liver-pancreas and anti-smooth muscle autoantibodies in a 66-year-old woman. Abnormal clinical and biochemical parameters resolved after drug withdrawal, but six months later anti-soluble liver-pancreas antibodies remained positive and liver biopsy showed chronic hepatitis and septal fibrosis. Furthermore, our patient has a HLA genotype associated with autoimmune hepatitis.ConclusionPatient follow-up will disclose whether our patient suffers from an autoimmune disease and if the presence of anti-soluble liver antigens could precede the development of an autoimmune hepatitis, as the presence of antimitochondrial antibodies can precede primary biliary cirrhosis.

The ‘EpiEnlist’ project: a dermo‐epidemiologic study on a representative sample of young Italian males. Prevalence of selected pigmentary lesions

Few studies on the prevalence and incidence of many skin conditions in the general population are available because it is difficult to submit to dermatologic examination large samples of seemingly healthy population. The aim of this study was to estimate the prevalence of several skin conditions among a sample that is deemed to be representative of the general population of young men living in southern Italy. Potential conscripts resident in the coastal regions of southern Italy and called at the age of 18 to the Draft's Council Medical Unit in Taranto underwent a clinical and instrumental examination to evaluate their psycho-physical fitness to compulsory service in Italian Navy. From January 1998 to April 2004 a dermo-epidemiologic project named EpiEnlist (EPIdemiology in ENLISTed Men) project was carried out by the Department of Dermatology of the Italian Navy Hospital in Taranto under the auspices of the Italian Group for Epidemiological Research in Dermatology. All the subjects showing skin lesions evocative of neurofibromatosis (NF), congenital melanocytic nevus (CMN), Becker nevus (BN), and vitiligo were referred to the Department of Dermatology of the Italian Navy Hospital for confirming the diagnosis. The confirmed cases were recorded in a predefined patient's card, containing the main anamnestic, clinical, instrumental, and laboratory data. Because the recording of the various conditions started and ended in different times, the total number of examined subjects varied. NF type 1 was diagnosed in 6 of 34 740 subjects [prevalence 1:5735 or 0.017%; 95% confidence interval (95% CI), 0.0008-0.0037], CMN in 157 of 23 354 (prevalence 1:148 or 0.67%; 95% CI, 0.57-0.79). BN was observed in 70 of 27 954 young men (prevalence 1:399 or 0.25%; 95% CI, 0.15-0.35), and its mean age of appearance was 11.9 years (minimum 5-maximum 17). In 41 subjects (58.6%), the age of appearance was over 10 years. Vitiligo was recorded in 60 of 34 740 persons (prevalence 1:579 or 0.17%; 95% CI, 0.13-0.22). In 40 subjects with vitiligo, the blood test was done: in 40% of these circulating autoantibodies, mainly anti-thyroid (25.6%) and anti-smooth muscle (17.3%) autoantibodies were detected, but only in 5% of cases, a thyroid disease was diagnosed, and no other sign of autoimmune diseases was observed. The epidemiological data of the skin conditions considered in the present study can be considered roughly in agreement with those reported in the available surveys. Because they were obtained in a large sample of Italian young males from the general population, they can be useful for therapeutic and preventive interventions by the public health organizations.

Severe Food Allergy as a Variant of IPEX Syndrome Caused by a Deletion in a Noncoding Region of the FOXP3 Gene

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX; OMIM 304930) syndrome is a congenital syndrome characterized by autoimmune enteropathy, endocrinopathy, dermatitis, and other autoimmune phenomena. In the present work, we aimed to uncover the molecular basis of a distinct form of IPEX syndrome presenting at the edge of autoimmunity and severe allergy. The FOXP3 gene was sequenced, FOXP3 messenger RNA (mRNA) was quantified by real-time polymerase chain reaction (PCR), and protein expression in peripheral blood lymphocytes was analyzed by flow cytometry after intracellular staining. In coculture experiments (CD4(+)CD25(-) and CD4(+)CD25(+) cells), the functions of regulatory T cells were analyzed. Expression of interferon gamma and interleukin 2 and 4 mRNA within the inflamed intestinal mucosa was quantified by real-time PCR. Here, we describe a distinct familial form of IPEX syndrome that combines autoimmune and allergic manifestations including severe enteropathy, food allergies, atopic dermatitis, hyper-IgE, and eosinophilia. We have identified a 1388-base pair deletion (g.del-6247_-4859) of the FOXP3 gene encompassing a portion of an upstream noncoding exon (exon -1) and the adjacent intron (intron -1). This deletion impairs mRNA splicing, resulting in accumulation of unspliced pre-mRNA and alternatively spliced mRNA. This causes low FOXP3 mRNA levels and markedly decreased protein expression in peripheral blood lymphocytes of affected patients. Numbers of CD4(+)CD25(+)FOXP3(+) regulatory T cells are extremely low, and the CD4(+)CD25(+) T cells that are present exhibit little regulatory function. A new mutation within an upstream noncoding region of FOXP3 results in a variant of IPEX syndrome associating autoimmune and severe immunoallergic symptoms.

Autoantibodies to Vascular Smooth Muscle Are Pathogenic for Vasculitis

We have previously shown that microvascular smooth muscle activates CD4+ T lymphocytes in sterile co-culture, presents antigen, and produces inflammatory cytokines. Adoptive transfer of lymphocytes co-cultured with syngeneic smooth muscle cells to healthy recipient mice results in vasculitic lesions predominantly in postcapillary venules. The present study assessed the pathogenic role of immunoglobulin and B cells in a murine model of vasculitis. Here, we show that transferred B cells, including plasmablast cells, accumulated, persisted, and proliferated in lung and secondary lymphoid organs of recipient mice. The induction of vasculitis was accompanied by production of IgM and IgG2a autoantibodies specific for vascular smooth muscle intracellular antigens. Circulating immunoglobulin had a pathogenic role in this vasculitis model, because the disease could be induced by transfer of serum from vasculitic mice to untreated animals but not by transfer of serum depleted of anti-smooth muscle autoantibodies. Additionally, the pathogenic mechanisms triggered by the transfer of vasculitogenic serum were dependent on T lymphocytes because both wild-type and B cell-deficient mice developed the disease after serum transfer, whereas RAG2-deficient mice did not. Thus, immunoglobulin and cell-mediated pathways work in concert to produce vasculitis in this model.

P0313 LOW LEVEL OF IGA AND SERUM AUTOIMMUNITY ???FACTORS WITH NEGATIVE INFLUENCE ON THE RESPONSE TO INTERFERON TREATMENT IN CHRONIC VIRAL HEPATITIS IN CHILDREN?

Introduction: Interferon treatment represents the main option in chronic viral hepatitis in children. The low level of serum IgA is considered to be associated with autoimmune manifestations. The association of autoimmunity in evolution of chronic viral hepatitis lead to a severe evolution and a bad response to the treatment with Interferon. The aim of our study was to evaluate the influence of serum immunoglobulin level (mainly IgA by the link to autoimmunity) on the chronic viral hepatitis evolution and on the response to interferon treatment. Methods: We have studied 45 pediatric patients (between 6 year old and 20 year and 4 month old) with chronic viral hepatitis B. We have analyzed the serum level of immunoglobulins, the presence of autoimmunity serum markers by immunofluorescence (antinuclear antibodies, anti-smooth muscle autoantibodies, liver-kidney autoantibodies). The response to Interferon treatment as complete response (anti HBs antibodies) or partial response (anti HBe antibodies) was analyzed related to the serum level of IgA and the presence of serum autoantibodies. Results: We have found low levels of IgA in 11 patients (24,44%) of all 45 patients. Only 2 patients with low level of IgA presented autoantibodies (smooth muscle autoantibodies) in evolution. The level of IgG and IgM were high in patients that have increased necrosis and inflammation on liver biopsy. The response to Interferon treatment was worst in patients with serum immune deficiency, just 2 cases have partially seroconversion (18,18%). Also the response was worst in patients that present autoantibodies in evolution, but we could not make a statistically significant link between low level of IgA – autoimmunity – response to interferon treatment (anti HBe appearance). Conclusion: The evolution of chronic viral hepatitis B is influenced by the level of serum immunoglobulins mainly in cases with increased necrosis and inflammation. In patients with low levels of IgA we have to evaluate the association or predisposition to autoimmunity. In these cases the follow-up become more important related to the interferon treatment as the response could be negative and the disease evolution could be severe.

Frequency and Levels of Autoantibodies in Healthy Adult Omanis

A previous pilot study showed a high frequency of anti-smooth muscle autoantibody in Omani blood donors and pregnant women. We conducted this larger-scale study to investigate the frequency and significance of several autoantibodies in healthy individuals from different regions of Oman. Sera obtained from 1537 healthy Omanis (1153 males and 384 females), ranging in age from 18 to 57 years, were tested for the presence of ten different autoantibodies using indirect immunofluorescence, haemagglutination and latex agglutination techniques. Low levels of autoantibodies were detected in 33.5%, whereas a few individuals (1.8%) showed high autoantibody titres. Anti-smooth muscle autoantibodies (ASMA) were the most prevalent (11%). Anti-nuclear autoantibodies (ANA) were the second most prevalent (7.6%). Anti-thyroid microsomal autoantibodies (ATMA) and anti-thyroglobulin autoantibodies (ATA) were present in 6.5% and 4.4% of individuals, respectively. The other autoantibodies were detected much less frequently: anti-parietal cells autoantibodies (APCA) were found in 1.6%, anti-brush border antibodies (ABBA) in 1.3%, anti-reticulin autoantibodies (ARA) in 1%, antimitochondrial antibodies (AMA) in 0.8%, antiglomerular basement membrane antibodies (AGBMA) in 0.7% and rheumatoid factor (RF) in 0.4%. The data indicate that autoantibodies are present in healthy Omani individuals, and therefore caution should be taken when interpreting laboratory results of patients suspected of having autoimmune disease.

The liver in celiac disease.

The liver in celiac disease.

Clinical, serological and genetic study in patients with CREST syndrome.

To assess the clinical, serological and genetic features of Japanese patients with CREST syndrome. Clinical features, autoantibodies and human histocompatibility leukocyte antigen (HLA) typing were studied in thirty patients with CREST syndrome, including 29 females and one male, with a mean age of 59.0 years (ranging from 40 to 76 years). Interstitial pneumonia on chest X-ray and renal involvement were rare. Mitral regurgitation and tricuspid regurgitation were present in 56.7% and 76.7%, respectively. Sjören's syndrome (SS) and primary biliary cirrhosis (PBC) were highly associated, however the positivity of the marker antibodies to those syndromes, such as anti-SSA, anti-SSB, anti-mitochondrial (AMA) and anti-smooth muscle autoantibodies were less frequent than that of primary SS and PBC without the other autoimmune diseases. The histological findings of PBC were all early stages in Scheuer's classification. HLA-Cw6 were associated with CREST-PBC overlap syndrome (p<0.05). However the HLA antigen was not correlated with CREST syndrome, and the frequency of HLA-DR2 between CREST syndrome with or without PBC was significantly different (p<0.01). It was suggested that there was a genetic difference between CREST syndrome alone and CREST-PBC overlap syndrome and there were differences (the positivity of AMA and the severity of bile duct lesion) between PBC and CREST-PBC overlap syndrome.

Serological Markers of Autoimmunity in Renal Transplant Patients with Chronic Hepatitis C

The aims of this prospective study were to assess the frequency of serological markers of autoimmunity and cryoglobulins in renal transplant (RT) patients presenting with chronic hepatitis C, and to correlate them with serum alanine aminotransferase (ALT) levels, hepatitis C virus (HCV) genotypes and viremia, and HLA-DR phenotypes. Three groups of patients were studied: group I comprised 74 HCV+ve RT patients; group II, 33 HCV–ve RT patients, and group III, 13 HCV–ve/hepatitis B virus (HBV)-positive RT patients. The three groups did not differ significantly according to their mean age, sex ratio and baseline immunosuppression.Serum specimens of these patients were tested for complement (hemolytic activity (CH₅₀), C3, C4 and properdin factor B (PFB) components, rheumatoid factor (RF), immunoglobulin patterns, circulating immune complexes, and autoantibodies including antinuclear (ANA), anti-smooth muscle (ASMA), antimitochondrial, antithyroid microsomal (ATM), antithyroglobulin (ATG) and anti-LKM1 autoantibodies. We also looked for the presence of cryoglobulins in groups I and III. Cryoglobulinemia of type II was present in 2 patients of group I (2.7%) which was associated in 1 case with de novo membranoproliferative glomerulonephritis but was not found in any of the patients of group III. RF (>40 U/ml) were more frequently observed in groups I (55.4%) and III (46%) than in group II (20.6%), although the difference was not statistically significant (p = 0.06). Oligoclonal or monoclonal serum immunoglobulin patterns were present in 16.2% of the patients in group I, 15.4% in group III and only 3.3% in group II (p = 0.07). There was no significant difference between the prevalence of at least one autoantibody in the three groups (ranging from 38.5 to 50%), and neither was the frequency of ANA (23–36.6%), even at a high titer i.e. above 1:320, or ASMA (13.5–23%) significantly different. Conversely, tissue-specific autoantibodies, i.e. ATM, ATG and anti-LKM1, were only observed in HCV+ve patients. CH₅₀, C3, C4 and PFB levels were significantly lower in group I than in group II, although values below the normal ranges were observed only for CH₅₀ and C3 and were mostly found in the HCV+ve RT patients. Circulating immune complexes detected by nephelometry were at similar levels in the three groups, within the normal ranges. The occurrence of at least one autoantibody and/or the presence of RF >40 U/ml did not correlate with either serum ALT levels or a given HLA-DR phenotype in any of the three groups, nor did they correlate with HCV genotype or HCV viremia in group I. In conclusion, this study shows that contrary to HCV+ve immunocompetent patients, HCV+ve RT patients rarely present with cryoglobulinemia and have the same frequency of non-organ-specific autoantibodies as HCV–ve RT patients. Conversely, antithyroid autoantibodies are only observed in the former group. Finally, serological markers of autoimmunity are not related to serum ALT levels, HLA-DR phenotype, HCV viremia or HCV genotype in HCV+ve RT patients.

Hepatocellular carcinoma complicating autoimmune hepatitis: Role of hepatitis C virus

The risk of hepatocellular carcinoma in autoimmune hepatitis is low, even in patients with long-standing cirrhosis. Because of the increasing recognition of an association of hepatitis C virus (HCV) with autoimmune hepatitis, at least in some geographical areas, and with hepatocellular carcinoma (HCC) (hepatoma), we have examined eight cases (4 male, 4 female) who presented between 1985 and 1993 with hepatoma complicating autoimmune hepatitis. All had steroid-responsive autoimmune hepatitis with serum anti-smooth muscle and anti-nuclear autoantibodies. Median duration of disease was 17.1 years, and all patients had biopsy-proven cirrhosis. One patient had a history of intravenous drug abuse, and four had previously received blood transfusions. Serum samples (stored at -20 degrees C from up to 9 years before diagnosis of hepatoma) were tested for anti-hepatitis C virus antibodies by a second-third-generation assay and for HCV RNA by the polymerase chain reaction method using primers from the 5'noncoding region. Tissue from liver adjacent to tumor areas was subjected to polymerase chain reaction along with tissue from previous liver biopsy specimens (taken up to 19 years before diagnosis of hepatoma) in all patients. Six patients had evidence of HCV infection: four seropositive for HCV RNA (two of whom were also anti-HCV positive) and two seronegative for HCV RNA and anti-HCV but with HCV RNA in liver tissue at presentation with hepatoma. Retrospective testing showed probable acquisition of HCV through blood transfusion in the four transfused patients.(ABSTRACT TRUNCATED AT 250 WORDS)