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Biomedical subjects

M Rizzetto

Publications and source records attributed to M Rizzetto.

At least 127 records · Page 7Linked to original sources
PubMed2000

Chronic hepatitis D: a vanishing Disease? An Italian multicenter study.

Hepatitis delta virus (HDV) was responsible for a high proportion of cases of acute and chronic liver disease in Southern Europe during the 1970s. Some data suggest that by the 1990s HDV circulation had substantially declined. We have assessed the prevalence of HDV infection and its clinical impact in 834 Italian hepatitis B surface antigen (HBsAg) carriers in 1997. Anti-HDV antibodies were sought in all consecutive chronic HBsAg carriers observed in 14 referral liver units throughout Italy. Risk factors for anti-HDV positivity were evaluated. Anti-HDV antibodies were found in 69 of 834 (8.3%) HBsAg-positive patients. Cohabitation with an anti-HDV-positive subject, intravenous drug addiction, residence in the South of the country, and the presence of cirrhosis were independently associated with the presence of anti-HDV antibodies. The overall prevalence of anti-HDV antibodies was lower than those observed in 2 multicenter surveys performed in 1987 and 1992 (23% and 14%, respectively). By 1997, the percentage of anti-HDV-positive subjects had sharply decreased in the 30 to 50 years age group, whereas it was almost unchanged in subjects over 50 years of age. The highest prevalence of anti-HDV antibodies (11.7%) was found in patients with cirrhosis. This prevalence was as high as 40% in the 1987 study. The circulation of HDV sharply decreased in Italy, by 1.5% per year, from 1987 to 1997. This decrease resulted mainly from the reduction in chronic HDV infections in the young, for whom high morbidity and mortality rates were recorded in the past. The results anticipate the almost complete control of HDV infection in the near future.

Adult↗
PubMed2000

Posttransplantation prevention and treatment of recurrent hepatitis B.

Prophylaxis of Recurrent Hepatitis B. 1. Although standard prophylaxis with antibody to hepatitis B surface antigen immunoglobulins (HBIG) is effective, it is difficult to administer and must be administered indefinitely. 2. Preemptive therapy with lamivudine reduces the early risk for recurrence after transplantation, but maintenance with either famciclovir or lamivudine has been ineffective in sustaining remission. 3. The combination of preemptive lamivudine with HBIG prophylaxis may be the most effective treatment to prevent hepatitis B virus reinfection. Treatment of Recurrent Hepatitis B. 1. Interferon-alpha, ganciclovir, and famciclovir have not been helpful. 2. Lamivudine appears promising, but its long-term efficacy is unproven; in immunosuppressed transplant recipients, the rate of emergence of YMDD mutants is high and accelerated, and their emergence is aggravated by consistent liver morbidity.

Antiviral Agents↗
PubMed2000

Helicobacter infection and cirrhosis in hepatitis C virus carriage: is it an innocent bystander or a troublemaker?

Since it has been shown that Helicobacter hepaticus causes both chronic hepatitis and hepatocellular carcinoma (HCC) in mice, it is suggested that differences in the progression of chronic hepatitis C may be due to a cofactor stemming from co-infection by bacteria, especially Helicobacter pylori, and/or other Helicobacter species. An assessment was made of the prevalence of H. pylori infection in HCV-positive cirrhotic patients. The presence of Helicobacter species (spp). was evaluated in resected liver tissue from HCC patients. Serum anti-H. pylori IgG antibodies were determined in 70 males with a clinical and/or histological diagnosis of cirrhosis and HCV infection and in 310 age-matched male blood donors. The prevalences of H. pylori antibody were 77% (54/70) and 59% (183/310) (P 0.004). Primers identifying 26 Helicobacter species were used to determine the presence of the genomic 16S rRNA of this genus in liver tissue resected from 25 cirrhotic HCC patients. Genomic sequences corresponding to H. pylori and H. pullorum were identified in 23 of these 25 livers. Together, these findings support the proposal that H. pylori is implicated in the pathogenesis and progression of cirrhosis, particularly in HCV-infected individuals. Involvement of Helicobacter spp. in HCC also seems highly possible.

Animals↗
PubMed2000

Covered metal stents for management of inoperable malignant colorectal strictures.

BACKGROUND: Metal stents have been reported as an effective alternative to surgery for the palliation of patients with colorectal neoplastic obstruction. Because most of the published series describe the use of uncovered stents, the purpose of our study was to prospectively evaluate the effectiveness, feasibility, safety, and outcome of covered stents for the palliative treatment of malignant colorectal strictures. METHODS: Sixteen patients with advanced distal colorectal cancer underwent placement of 10 and 12 cm long, 23 mm diameter covered stents under fluoroscopic and endoscopic control. Clinical and endoscopic follow-up was scheduled at 3- to 6-week intervals. RESULTS: Stent insertion was successful in 15 of 16 patients (93%). Perforation occurred in one patient during stent placement requiring colostomy. Relief of bowel obstruction was documented in all successfully treated patients. The median follow-up was 21 weeks (range 1 to 46). No recurrence of obstruction was observed during the follow-up period. Stent migration occurred in 2 patients, 7 and 21 days after stent placement. CONCLUSIONS: Covered stents may provide safe and effective palliation of patients with malignant rectosigmoid strictures. Prolonged luminal patency and sealing of fistulous tracts are potential advantages of covered versus uncovered stents in the palliative treatment of colorectal malignancies. ¿

Aged↗
PubMed2000

Response of pre-core mutant chronic hepatitis B infection to lamivudine.

The proportion of chronic liver disease associated with the pre-core mutant of hepatitis B virus (HBV) infection is increasing, particularly in Mediterranean Europe and in Asia. The pre-core mutant HBV is unable to produce hepatitis B e antigen (HBeAg), so that patients with this variant do not present with HBV characterised by HBeAg in the serum. Pre-core mutant chronic hepatitis B infection usually proceeds to serious liver disease. Wild-type HBV infection may be mild and respond relatively well to interferon (IFN) alpha therapy, but IFN alpha is not an effective therapeutic option in pre-core mutant hepatitis B infection and new therapeutic options are needed. Clinical data show that lamivudine is an effective treatment for patients with pre-core mutant hepatitis B. There is profound suppression of HBV replication and improvement in indicators of liver disease in most patients. In conclusion, lamivudine is suitable for treatment of a wide range of patients with chronic hepatitis B, including those with pre-core mutant HBV infection.

Adolescent↗
PubMed2000

Hepatocellular carcinoma in a non-cirrhotic liver. Two case reports and literature review.

Hepatocellular carcinoma (HCC) is closely associated with cirrhosis, but it also develops, although much less frequently, in a non-cirrhotic liver. It is suspected that hepatocellular carcinoma has a different etiology when associated and not associated with chronic liver disease. We report two cases of patients with hepatocellular carcinoma that developed in a non-cirrhotic liver. In the first case we describe an incidental liver nodular lesion containing multiple foci of HCC including pseudogland or trabecular formation and areas of sclerosis. The non-cancerous parenchyma of the liver was histologically unremarkable except for mild fatty changes of hepatocytes and minimal dysplasia. The second case describes a combined hepatocellular carcinoma and cholangiocellular carcinoma (CCC) (mixed carcinoma) in a patient who was serologically negative for both hepatitis B and C viruses. The adjacent liver parenchyma showed mild piecemeal necrosis and mild lobular activity compatible with chronic viral hepatitis, but cirrhosis was not established. This case appears to indicate that mixed type carcinoma can develop in a non-cirrhotic liver, with CCC being far more dominant than HCC; such a finding is extremely unusual, based on previously published reports.

Aged↗
PubMed2000

Previous tuberculosis, hepatitis C virus and lichen planus. A report of 10 cases, a causal or casual link?

We report 10 cases of lichen planus (LP) and chronic liver disease linked to HCV. The mean age was 63.4 +/- 5.1 years (range 51-73), five were female; six patients had an established cirrhosis of the liver, as shown by either a liver biopsy or the ultrasonographic and biohumoral evidence. The remaining four patients had chronic hepatitis. Histological examination confirmed the presence of LP: the localization of the dermatosis was restricted to the skin in four patients, to the mucous membranes in five (4 atrophic erosive and one erosive) while the remaining had mucous-cutaneous localization. A type II cryoglobulinemia was demonstrated in two and a type III in one of the patients, while no one had otherwise circulating autoantibodies (anti-nuclear, anti-smooth muscle, anti-liver kidney microsomal type 1 and anti-mitochondrial antigens) such as other etiological factors of liver disease. In six of the patients the history was positive for previous Mycobacterium tuberculosis infection. In clinical practice the patients with chronic liver disease and HCV infection can also suffer from severe extrahepatic manifestations, including lichen planus.

Aged↗
PubMed2000

Ischemic cardiovascular disease and Helicobacter pylori. Where is the link?

Coronary heart disease (CHD) is the leading cause of death in western countries. Although several major risk factors have been identified, they fail to account for all the epidemiological variants of the disease, thus warranting research into novel causal agents. Cardiovascular diseases have long been associated with chronic infections acting through the activation of inflammatory pathways, and antibiotic therapy has been shown to produce a dramatic decrease in the rate of disease recurrence in patients with a history of myocardial infarction or unstable angina. The link between Helicobacter pylori (H. pylori) infection and CHD, first described by Mendall et al. in 1994, has been the subject of a multitude of epidemiological and clinical studies; however, these have been so heterogeneous that not two of them are based on a comparable selection of patients and focused on the same kind of disease, e.g. stable coronary heart disease or acute myocardial infarction. Evidence from animal studies supports the thesis that H. pylori plays an extremely important role in the acute phase of myocardial infarction: the bacterium causes platelet aggregation and induces pro-coagulant activity in experimentally infected mice. H. pylori may also contribute to atherosclerosis through an auto-immune process against endothelial cells or an increased concentration of homocysteine in the blood due to decreased levels of folic acid and cobalamin. The exact role of H. pylori cannot yet be fully assessed: there is a clear and present need for further studies with appropriate epidemiological and clinical approaches to investigate through prospective and interventional trial the possible causal relationship between H. pylori and CHD.

Animals↗
PubMed2000

[Ischemic cardiovascular diseases. Correlation with Helicobacter pylori infection].

Coronary heart disease is the primary cause of mortality in western countries. The well-established ("classical") risk factors cannot fully explain epidemiological variations of this disease. From several years infections have been linked to ischemic vascular events and recent studies pointed to the role of Helicobacter pylori (H. pylori), a spiral Gram negative bacterium, that chronically infects human stomach and is involved in the pathogenesis of gastritis and peptic ulceration. Systematic reviews of studies have suggested the existence of a possible weakly positive association between this bacterium and coronary heart disease, but this could be due to confounding bias and influenced by the degree of investigations heterogeneity. Experiments from animal studies demonstrated that H. pylori infection in mice induces the formation of platelet aggregates and in contrast to Chlamydia pneumoniae it has not been found in the plaque: therefore, the role of H. pylori, could be even more important in the acute phase of myocardial infarction. There is the need for extensive prospective studies to evaluate the incidence of these diseases in relation to the presence of H. pylori infection. Appropriately randomized studies employing an antibiotic treatment for patients affected by ischemic vascular disease will answer the question of whether H. pylori has a causal role in the pathogenesis of acute myocardial infarction and ischemic stroke.

Coronary Disease↗
PubMed2000

Management strategies in resection for carcinoma of the hepatic duct confluence: how to increase the resectability rate. Our experience and literature review.

The resectability rate of hilar bile duct carcinoma is reported to be variable and to inversely correlate with the size of the associated liver resection. In an attempt to reduce the risk of postoperative liver failure, the induction of a hypertrophy of remnant liver by preoperative portal vein embolization (PVE) has been proposed. We hereby analyse the results and the technical aspects of this procedure along with our personal experience.

Bile Duct Neoplasms↗
PubMed2000

Therapy for chronic hepatitis B. Present status.

Up to now Interferon (IFN) has been the only licensed treatment for chronic type B and D viral hepatitis. However, IFN monotherapy is efficacious only in HBeAg positive chronic hepatitis B and is aggravated by important side effects in many patients. To overcome the limits of IFN monotherapy, combination therapies of this cytokine together with other synergistic drugs have been proposed and many antivirals that directly act on Hepatitis B Virus (HBV) synthesis have been developed. Combination therapies with acyclovir, levamisole, and cortisone have not been more advantageous than IFN alone. Of the antivirals, Adenine Arabinoside monophosphate, though active against HBV, causes severe neurotoxicity and Famciclovir has not shown significant efficacy in a large multicenter study of chronic HBeAg positive hepatitis. Lamivudine appears the most promising in terms of clinical benefit, safety and tolerance. It is active on wild type HBV as well as on HBeAg-minus variants of the virus. However, although HBV is consistently repressed while on therapy, only a part of the patients are cured or remain in remission after Lamivudine withdrawal. Maintenance therapy is in order, but the long-term use of Lamivudine is complicated by the emergence of polymerase gene-mutants which may recapitulate disease. Combination with other antivirals active also against Lamivudine escape mutants opens promising new prospects. There is as yet no valid therapy for chronic HDV hepatitis; IFN is of no benefit in most cases.

Journal Article↗
PubMed2000

Therapy for chronic hepatitis C. Present status.

Interferon (IFN) is the only treatment so far approved world-wide for chronic hepatitis C. Though proof of long term benefit is lacking, metanalyses have provided extrapolations that substantiate the hypothesis that this therapy can modify favourably the natural history of the disease. Results, however, are limited and new forms of therapy, complementary or alternative to IFN, have been developed. Efforts to ameliorate the results of alpha-IFN mono therapy in chronic hepatitis C with new IFNs, or the manipulation of IFN monotherapy so as to obtain the maximum results compatible with tolerance, have not produced a better results than the classical protocols of alpha IFN monotherapy. Important recent therapeutic progress that surpasses and advances the results obtained with single IFN therapy is the combination of IFN with ribavirin, with which overall rates of response have increased three times compared to IFN monotherapy. Combination therapy has become the treatment of choice for IFN naive patients as well as for IFN relapses; it is not efficacious in patients who have not responded to IFN.

Journal Article↗
PubMed2000

Hepatocellular carcinoma: screening and therapy.

Treatment of the liver cancer (LC) patient is often problematic as the tumour is identified at an advanced stage: the frequent coexistence of cirrhosis limits the use of surgical resection, there is no efficacious chemotherapy, and in patients treatable with liver transplant, indication is rendered uncertain from the point of view of cost-effectiveness and the high risk of recurrence of the tumour and hepatitis infection. Surgical resection appears to be the treatment of choice in patients with a liver tumour in a ''healthy'' liver. Instead, orthotopic liver transplant is the most valid indication for patients with cirrhosis and tumours of dimensions smaller than 2-3 cm. Nevertheless, due to the lack of organs palliative treatments, like surgical resection, PEI and TACE are the most indicated in patients with advanced neoplastic disease, in practice patients with TNM III and IV; radiotherapy with protons and the coagulation of the tumour by microwaves or laser fibres are also used in the attempt to slow down the progress of the neoplastic process. These methods may increase the possibility of cure in well chosen patients. In some patients the most effective approach may be the combined use of various therapies, such as TACE, PEI and surgery.

Journal Article↗
PubMed1999

Autoantibodies in human chronic graft-versus-host disease after hematopoietic cell transplantation.

Primary biliary cirrhosis (PBC) and graft-versus-host disease (GVHD) are thought to have common immunopathologic features and previous studies have reported that 5.2 to 81% of patients with chronic GVHD after allogeneic hematopoietic cell transplant have antimitochondrial antibodies (AMA). We studied a total of 89 patients with chronic GVHD and 60 controls for AMA reactivity by ELISA and immunoblotting using recombinant PDC-E2, BCOADC-E2, and OGDC-E2, immunoblotting of beef heart mitochondrial proteins, and reactivity to nuclei, smooth muscle (ASMA), ribonucleoprotein JO-1, extractable nuclear antigen, nuclear proteins SSA/ SSB, ribonucleic P proteinase III, cardiolipin (ACA), liver kidney microsomal, thyroid microsomal, myeloperoxidase, and the reactivity of rheumatoid factor. A subset of 60 chronic GVHD sera were tested for reactivity to gp210 and LBR. Finally, liver tissue from patients with chronic GVHD and PBC was studied by immunohistochemistry to determine whether there was comparable abnormal apical staining of biliary epithelial cells using PDC-E2-specific monoclonal antibodies. Surprisingly, there were no AMA found in the sera from the 89 patients with chronic GVHD. Review of published data on AMA in GVHD suggests that previous results were primarily false positives. In contrast, sera from the patients with GVHD did have a variety of other autoantibodies and, in particular, 20/89 (22.4%) positive ANA, 23/89 (25.8%) positive ASMA, and 9/89 (10.1%) positive ACA. The other autoantibodies assayed were not statistically different from controls. Finally, abnormal biliary epithelial luminal staining of bile ducts was found, as expected, in liver tissue of patients with PBC but was absent in chronic GVHD.

Adult↗
PubMed1999

Acute myocardial infarction and Helicobacter pylori seropositivity.

Infectious agents including Helicobacter pylori, have been linked to coronary heart diseases on epidemiological and pathogenetic grounds. Classical risk factors fail to explain all the epidemiological variations of the disease. Our aim was to investigate the association of acute myocardial infarction with Helicobacter pylori infection in a case-control study by comparing a group of male patients with a control group of blood donors matched for sex and age. We investigated the classical cardiovascular risk factors in all patients. We studied 44 consecutive male patients, aged 40-65 years, admitted for acute myocardial infarction to the Coronary Care Unit at Novi Ligure Hospital in northern Italy. Helicobacter pylori infection was assessed by measurement of antibodies (IgG) against Helicobacter pylori in blood. Volunteer blood donors attending Molinette Hospital Blood Bank in Turin, northern Italy served as controls. Among the patients we investigated the presence of hypertension, cholesterol and glucose levels in serum, fibrinogen in plasma, smoking habits, and social class. Helicobacter pylori infection was present in 34 of 44 (77%) patients and in 183 of 310 (59%) controls (P<0.05); the odds ratio was 2.36 (95% confidence interval 1.08-5.31). Classical cardiovascular risk factors did not differ among patients with and without Helicobacter pylori infection. In conclusion, patients with acute myocardial infarction had a significantly higher prevalence of Helicobacter pylori infection than the control population. The classical risk factors for cardiovascular diseases were equally distributed among patients irrespective of their Helicobacter pylori status.

Adult↗
PubMed1999

Changing pattern of chronic hepatitis D in Southern Europe.

BACKGROUND & AIMS: The aim of this study was to assess changes in the clinical pattern of hepatitis D virus (HDV) infection in Italy, brought about by improved control of hepatitis B and D viruses, and to establish the natural history of chronic hepatitis D. METHODS: Histological diagnosis and clinical features of 122 patients with HDV recruited from 1987 to 1996 in three Italian tertiary referral centers (Torino, northern Italy; San Giovanni Rotondo and Castellana Grotte, southern Italy) were compared with those of 162 patients collected in the same centers in the previous decade. Patients from both groups with at least 6 months of follow-up were included in a new subgroup to assess the natural history of the disease. RESULTS: Among 162 patients referred from 1977 to 1986, 9 (6%) had mild hepatitis at histology vs. 9 (8%) of 122 patients referred in the second decade; 105 (65%) vs. 21 (17%) had severe hepatitis; 46 (28%) vs. 38 (31%) had histological asymptomatic cirrhosis; and 2 (1%) vs. 54 (44%) had clinically overt cirrhosis. For 159 patients (121 men and 38 women; mean age, 34 +/- 11), a follow-up of more than 6 months was documented, and they were included in the natural history subgroup. After 78 +/- 59 months of follow-up, 112 (70%) survived free of liver transplantation: 9 underwent transplantation, 32 died of liver failure, and 6 of acquired immunodeficiency syndrome. Estimated 5- and 10-year probability of survival free of orthotopic liver transplantation was 100% and 100% for patients with mild hepatitis, 90% and 90% for severe hepatitis, 81% and 58% for histological asymptomatic cirrhosis, and 49% and 40% for clinical cirrhosis (P < 0.01), respectively. CONCLUSIONS: Occurrence of fresh and severe forms of hepatitis D has diminished greatly in Italy. Contemporary patients represent cohorts infected years ago who survived the immediate medical impact of hepatitis D. The disease has been asymptomatic and nonprogressive in a minority; in the majority, it rapidly advanced to cirrhosis but thereafter subsided with stable clinical conditions for more than a decade.

Adult↗