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Biomedical subjects

M Durazzo

Publications and source records attributed to M Durazzo.

At least 37 records · Page 2Linked to original sources

Efficacy and safety of interferon alfa therapy in chronic hepatitis C with autoantibodies to liver-kidney microsomes.

Interferon alfa (IFN) therapy is efficacious in chronic viral hepatitides. It may, however, cause adverse immunologic reactions in patients with concomitant autoimmune phenomena. A minority of patients with chronic type C hepatitis have antibodies against liver and kidney microsomes (anti-LKM) in serum. We therefore carried out this study to find out whether IFN is safe and efficacious also in this subgroup. We treated 92 consecutive cases of chronic hepatitis C with IFN. Twelve patients had anti-LKM< and the remaining 80 tested negative to the anti-LKM. The hepatitis C virus (HCV) infection was diagnosed on the basis of positive anti-HCV and HCV-RNA tests. We compared the clinical and virological virological results of the therapy and the side effects found in the two groups. We found that the response to therapy and the outcome after 1 year of follow-up were similar. Treatment was discontinued in one anti-LKM-positive patient because of a drastic increase in ALT levels at the fourth month of therapy. No untoward effect was observed in the other cases. Hepatitis C patients with anti-LKM may be exposed to an increased risk of an adverse hepatitic reaction while being treated with IFN. However, we found that the extent of the risk was minimal compared with the expected benefits of the therapy. IFN is therefore recommended as the first therapy to choose in these patients. They must, however, be monitored more closely for possible liver dysfunction than the ordinary hepatitis C patient.

Adult↗

Molecular analysis of autoantigens in hepatitis D.

In contrast to hepatitis B virus infection, autoimmunity is common in chronic hepatitis D. In 1983, microsomal autoantibodies were described that differ from the previously described liver-kidney microsomal (LKM)-1 and LKM-2 antibodies. Therefore, these were named LKM-3. In addition, autoantibodies against basal layer cells of rat forestomach (basal cell layer antibodies (BCLA)) and thymic stellate epithelial cells (stellate epithelial cell antibodies (SECA)), as well as thymic reticular (thymic reticular antibodies) and perithymocytic cells (perithymocytic cell antibodies), were reported to be specifically associated with hepatitis D. Antinuclear antibodies against nuclear membrane lamin C were also found to be specifically associated with chronic hepatitis D. A molecular identification of the nonnuclear antigens has not been achieved apart from the observation that BCLA and SECA both recognize an antigen of 46 kDa and that these antibodies are immunologically cross-reactive. After the identification of cytochrome P450 2D6 as the major LKM-1 antigen and cytochrome P450 2C9 as the LKM-2 antigen, family 1 uridine diphosphate-glucuronosyltransferases have been identified as the molecules expressing the major LKM-3 autoepitope. Future studies will have to assess the possible pathogenetic and diagnostic relevance of these autoantibodies. However, chronic hepatitis D seems to be a good clinical model for the study of virus-induced autoimmunity in man.

Animals↗

Recognition of uridine diphosphate glucuronosyl transferases by LKM-3 antibodies in chronic hepatitis D.

Patients with chronic hepatitis D often have liver-kidney microsomal antibodies type 3 (LKM-3). These antibodies react with several microsomal antigens that have a molecular weight of 55 KDa and an isoelectric point of about 8. We studied the molecular nature of the antigen and, by immunoscreening a human liver cDNA expression library with KM-3 sera, found that uridine diphosphate glucuronosyl transferases (UGT) appeared as candidate antigens. We confirmed the identity of UGT as an antigen by reacting the sera with recombinant rabbit liver UGT proteins. Some sera reacted with rabbit UGT-2 proteins, but UGT-1 proteins were more sensitive and specific in detecting LKM-3 autoantibodies in patient sera. Anti-UGT-1 antibodies were detected in all LKM-3 positive sera from patients with hepatitis D and 1 out of 11 patients with autoimmune hepatitis type 2. Sera from patients who had hepatitis B only did not react with UGT proteins. The UGT proteins are part of the phase II enzymes of drug metabolism and are the first such enzymes to be identified as human autoantigens.

Antibody Specificity↗

Anti-GOR in hepatitis D: specific association with hepatitis C virus superinfection.

A group of 113 patients with chronic hepatitis D was investigated for the presence of anti-GOR and liver kidney microsomal antibodies. Eight patients were anti-GOR positive and also positive for hepatitis C virus-infection. In sera from 16 patients liver-kidney microsomal antibodies were detectable by immunofluorescence. They were classified as LKM-3 due to their fluorescence pattern. Two of the LKM-3-positive sera were also anti-hepatitis C virus and anti-human immunodeficiency virus positive. None of these patients were positive for anti-GOR. Fourteen sera from LKM-3-positive patients reacted in Western blot with a microsomal protein at 55 kDa that differs from the 50-kDa LKM-1 (cytochrome P450IID6) antigen. Our studies demonstrate that hepatitis D virus itself does not induce an autoimmune reaction against the GOR antigen and that autoimmunity to the LKM-3 antigen induced by hepatitis D virus infection does not correlated with anti-GOR. These studies support the specificity of the anti-GOR response for hepatitis C virus infection.

Autoantibodies↗

Analysis of hepatitis C virus genome in patients with autoimmune hepatitis type 2.

BACKGROUND/AIMS: Hepatitis C virus (HCV) RNA is detectable in a proportion of patients with autoimmune hepatitis type 2, which is characterized by liver-kidney microsomal antibodies (LKM). Therefore, the genotype and sequence of HCV were studied in these patients. METHODS: Sera from 43 LKM-positive and anti-HCV-positive patients (15 from Germany and 28 from Italy) and 82 LKM-negative and anti-HCV-positive patients (57 from Germany and 25 from Italy) were examined. RESULTS: Genotyping revealed that the rate of genotype III HCV according to Okamoto's classification in patients with LKM antibody-positive autoimmune hepatitis type 2 was higher than in LKM-negative patients (22.0% vs. 2.4%; P < 0.05). This was because of an increase of genotype III in our patients from Italy. No HCV mutations were found that show a closer sequence homology to cytochrome P450IID6, the major LKM-1 antigen. Deletions in the envelope and nonstructural region 5 were found. CONCLUSIONS: Because a specific HCV sequence is not associated with the induction of LKM-1 autoantibodies, future research must focus on host factors and possibly additional environmental factors.

Adult↗

Hepatitis type C after orthotopic liver transplantation: reinfection and disease recurrence.

We determined the prevalence of hepatitis C virus markers and the clinical course in patients transplanted for terminal type C or non-A, non-B cirrhosis. Hepatitis C virus infection recurred in 16 of 17 patients (94%) with type C cirrhosis (seropositive for hepatitis C virus prior to surgery) and in 10 of 11 patients (91%) with non-A, non-B cirrhosis whose hepatitis C virus status prior to surgery had not been determined. Markers of hepatitis C virus were detected in 4 of 16 liver transplants whose donors tested negative for hepatitis C virus prior to surgery; this figure represents the risk of hepatitis C virus acquisition from external sources at or after transplantation. In 18 of 26 reinfected patients aminotransferases increased after grafting and remained elevated throughout the 14 to 79 (mean 46.5) months of follow up. The histological findings varied from mild or moderate hepatitis in 15 patients to severe active hepatitis in two patients. Two patients developed cirrhosis; one of them died of intercurrent infection while she was receiving immunosuppressive therapy for chronic rejection. Patients transplanted for hepatitis C virus or non-A, non-B liver disease are at high risk of hepatitis C virus reinfection. However the course of recurrent hepatitis C is most often mild and compatible with a normal life and an excellent survival rate.

Adult↗

Hepatitis delta virus (HDV) infections. Epidemiological and clinical heterogeneity.

Heterogeneity is a feature of all aspects of HDV infection and biology. Epidemiological studies indicate wide variations in the global distribution of the virus, often with different and bizarre rates of prevalence within apparently homogeneous populations. The medical expression of the infection is likewise manifold, ranging from the asymptomatic carrier of HDV to terminal cirrhosis. The clinical variability is matched at the biological level by extensive molecular heterogeneities, as expected with a small RNA virus such as the HDV.

Hepatitis D↗

Hepatitis C virus-related chronic liver disease with autoantibodies to liver-kidney microsomes (LKM). Clinical characterization from idiopathic LKM-positive disorders.

This study was carried out on 33 patients who were sero-positive for liver-kidney microsomal antibodies (LKM) in order to examine clinical features and the presence of underlying hepatitis C virus infection. Twenty-four sera were positive for antibodies against HCV (anti-HCV) as detected by enzyme immunoassay and confirmed by recombinant immunoblot assay. These patients had chronic liver disease and the majority of those treated with interferon responded favourably. Three of the nine anti-HCV-negative patients had idiopathic chronic hepatitis and two responded favourably to steroids. Two patients were diagnosed as having toxic hepatitis and the other four had various extrahepatic disorders without evidence of liver involvement. The immunoblotting analysis showed reactivity with a 50 kDa microsomal protein which presumably corresponded to cytochrome P-450 db1 both in anti-HCV-positive and -negative sera. In addition a few anti-HCV-positive sera also reacted with a 35 kDa microsomal antigen. Autoimmune markers different from LKM were absent in both groups. The high prevalence of antibodies to the hepatitis C virus among LKM-positive sera confirms that this infection plays a role in forms of chronic hepatitis that had previously been labelled autoimmune. In patients with LKM the presence of anti-HCV may help to forecast a therapeutic response to interferon, while its absence may forecast response to steroid therapy.

Adolescent↗

Autoantibodies and response to alpha-interferon in patients with chronic viral hepatitis.

One hundred and fifteen patients with chronic type B, D and non-A, non-B hepatitis treated with recombinant alpha-interferon were tested for six different autoantibodies prior to or during therapy, and the course of treatment was compared in autoantibody-positive and -negative patients. Three out of 25 (12%) hepatitis B patients, 14 out of 30 (47%) hepatitis D patients and 19 out of 60 (32%) chronic non-A, non-B hepatitis carriers had baseline or post-therapy autoantibodies. The rate of response between patients with and without autoantibodies among B, D and non-A, non-B patients was, respectively, 67 vs. 79%, 23 vs. 25%, 70 vs. 61% (p = N.S.). No adverse reaction was observed in the 36 patients who had or developed nuclear, smooth muscle, parietal cells and thyroid autoantibodies during therapy. A patient with baseline antibodies against liver and kidney microsomes developed an icteric acute hepatitis at the fourth month of therapy, but five other patients with this reactivity responded to therapy uneventfully. The presence of autoantibodies before therapy or their induction following therapy is not a contraindication to the use of interferon in patients with chronic viral hepatitis.

Animals↗

[A case of hepatocarcinoma preceded by several years by "isolated" increase in alphafetoprotein].

Hepatocarcinoma (HCC), the most frequent malignant hepatic neoplasia, is sometimes difficult to diagnose at an early stage since the symptoms may be attributed to concomitant hepatic cirrhosis. The assay of alpha-fetoprotein associated with an ultrasound examination of the hepatic parenchyma is an important screening tool for high-risk patients. Ultrasound examination is considered the most sensitive method and alpha-fetoprotein is a supplementary diagnostic tool. Elevated alpha-fetoprotein only occasionally precedes morphological anomalies and even in these cases the neoplastic aspect emerges within a short period of time. The case reported here illustrates the "astronomic" increase of alpha-fetoprotein in a high-risk patient for HCC (positive HBsAg cirrhosis) without the manifest appearance of any instrumental or histological data confirming the presence of the tumour for two years. When the tumour was identified in instrumental tests it had spread throughout the entire hepatic parenchyma in a form which could no longer be treated using any form of therapy. The case reported here emphasizes the diagnostic value of alphafetoprotein in high-risk patients for HCC, even in the prolonged absence of all other data regarding neoplastic transformation.

Carcinoma, Hepatocellular↗