970 resultados para septal hepatic fibrosis


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OBJECTIVE Reliable tools to predict long-term outcome among patients with well compensated advanced liver disease due to chronic HCV infection are lacking. DESIGN Risk scores for mortality and for cirrhosis-related complications were constructed with Cox regression analysis in a derivation cohort and evaluated in a validation cohort, both including patients with chronic HCV infection and advanced fibrosis. RESULTS In the derivation cohort, 100/405 patients died during a median 8.1 (IQR 5.7-11.1) years of follow-up. Multivariate Cox analyses showed age (HR=1.06, 95% CI 1.04 to 1.09, p<0.001), male sex (HR=1.91, 95% CI 1.10 to 3.29, p=0.021), platelet count (HR=0.91, 95% CI 0.87 to 0.95, p<0.001) and log10 aspartate aminotransferase/alanine aminotransferase ratio (HR=1.30, 95% CI 1.12 to 1.51, p=0.001) were independently associated with mortality (C statistic=0.78, 95% CI 0.72 to 0.83). In the validation cohort, 58/296 patients with cirrhosis died during a median of 6.6 (IQR 4.4-9.0) years. Among patients with estimated 5-year mortality risks <5%, 5-10% and >10%, the observed 5-year mortality rates in the derivation cohort and validation cohort were 0.9% (95% CI 0.0 to 2.7) and 2.6% (95% CI 0.0 to 6.1), 8.1% (95% CI 1.8 to 14.4) and 8.0% (95% CI 1.3 to 14.7), 21.8% (95% CI 13.2 to 30.4) and 20.9% (95% CI 13.6 to 28.1), respectively (C statistic in validation cohort = 0.76, 95% CI 0.69 to 0.83). The risk score for cirrhosis-related complications also incorporated HCV genotype (C statistic = 0.80, 95% CI 0.76 to 0.83 in the derivation cohort; and 0.74, 95% CI 0.68 to 0.79 in the validation cohort). CONCLUSIONS Prognosis of patients with chronic HCV infection and compensated advanced liver disease can be accurately assessed with risk scores including readily available objective clinical parameters.

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Non-alcoholic fatty liver disease (NAFLD) is an increasingly common condition, strongly associated with the metabolic syndrome, that can lead to progressive hepatic fibrosis, cirrhosis and hepatic failure. Subtle inter-patient genetic variation and environmental factors combine to determine variation in disease progression. A common non-synonymous polymorphism in TM6SF2 (rs58542926 c.449 C>T, p.Glu167Lys) was recently associated with increased hepatic triglyceride content, but whether this variant promotes clinically relevant hepatic fibrosis is unknown. Here we confirm that TM6SF2 minor allele carriage is associated with NAFLD and is causally related to a previously reported chromosome 19 GWAS signal that was ascribed to the gene NCAN. Furthermore, using two histologically characterized cohorts encompassing steatosis, steatohepatitis, fibrosis and cirrhosis (combined n=1,074), we demonstrate a new association, independent of potential confounding factors (age, BMI, type 2 diabetes mellitus and PNPLA3 rs738409 genotype), with advanced hepatic fibrosis/cirrhosis. These findings establish new and important clinical relevance to TM6SF2 in NAFLD.

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BACKGROUND & AIMS Pegylated interferon-based treatment is still the backbone of current hepatitis C therapy and is associated with bone marrow suppression and an increased risk of infections. The aim of this retrospective cohort study was to assess the risk of infections during interferon-based treatment among patients with chronic HCV infection and advanced hepatic fibrosis and its relation to treatment-induced neutropenia. METHODS This cohort study included all consecutive patients with chronic HCV infection and biopsy-proven bridging fibrosis or cirrhosis (Ishak 4-6) who started treatment between 1990 and 2003 in five large hepatology units in Europe and Canada. Neutrophil counts between 500/μL-749/μL and below 500/μL were considered as moderate and severe neutropenia, respectively. RESULTS This study included 723 interferon-based treatments, administered to 490 patients. In total, 113 infections were reported during 88 (12%) treatments, of which 24 (21%) were considered severe. Only one patient was found to have moderate neutropenia and three patients were found to have severe neutropenia at the visit before the infection. Three hundred and twelve (99.7%) visits with moderate neutropenia and 44 (93.6%) visits with severe neutropenia were not followed by an infection. Multivariable analysis showed that cirrhosis (OR 2.85, 95%CI 1.38-5.90, p=0.005) and severe neutropenia at the previous visit (OR 5.42, 95%CI 1.34-22.0, p=0.018) were associated with the occurrence of infection, while moderate neutropenia was not. Among a subgroup of patients treated with PegIFN, severe neutropenia was not significantly associated (OR 1.63, 95%CI 0.19-14.2, p=0.660). CONCLUSIONS In this large cohort of patients with bridging fibrosis and cirrhosis, infections during interferon-based therapy were generally mild. Severe interferon-induced neutropenia rarely occurred, but was associated with on-treatment infection. Moderate neutropenia was not associated with infection, suggesting that current dose reduction guidelines might be too strict.

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BACKGROUND & AIMS Patients with chronic hepatitis C virus (HCV) infection may develop cirrhosis with portal hypertension, reflected by decreased platelet count and splenomegaly. This retrospective cohort study aimed to assess changes in platelet counts after antiviral therapy among chronic HCV-infected patients with advanced fibrosis. METHODS Platelet counts and spleen sizes were recorded in an international cohort of patients with Ishak 4-6 fibrosis who started antiviral therapy between 1990 and 2003. Last measured platelet counts and spleen sizes were compared to their pre-treatment values (within 6 six months prior to the start of therapy). All registered platelet count measurements from 24 week following cessation of antiviral therapy were included in repeated measurement analyses. RESULTS This study included 464 patients; 353 (76%) had cirrhosis and 187 (40%) attained sustained virological response (SVR). Among patients with SVR, median platelet count, increased by 35 x10(9) /L (IQR 7-62, p<0.001). In comparison, patients without SVR showed a median decline of 17 x10(9) /L (IQR -5-47, p<0.001). In a subgroup of 209 patients, median decrease in spleen size was 1.0 cm (IQR 0.3-2.0) for patients with SVR, while median spleen size increased with 0.6 cm (IQR -0.1-2.0, p<0.001) among those without SVR. The changes in spleen size and platelet count were significantly correlated (R=-0.41, p<0.001). CONCLUSIONS Among chronic HCV-infected patients with advanced hepatic fibrosis the platelet counts improved following SVR and the change in platelets correlated with the change in spleen size following antiviral therapy. These results suggest that HCV eradication leads to reduced portal pressure. This article is protected by copyright. All rights reserved.

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Transforming growth factor β (TGF-β) is a well characterized cytokine that appears to play a major role in directing the cellular response to injury, driving fibrogenesis, and, thus, potentially underlying the progression of chronic injury to fibrosis. In this study, we report the use of a novel TGF-β receptor antagonist to block fibrogenesis induced by ligation of the common bile duct in rats. The antagonist consisted of a chimeric IgG containing the extracellular portion of the TGF-β type II receptor. This “soluble receptor” was infused at the time of injury; in some experiments it was given at 4 days after injury, as a test of its ability to reverse fibrogenesis. The latter was assessed by expression of collagen, both as the mRNA in stellate cells isolated from control or injured liver and also by quantitative histochemistry of tissue sections. When the soluble receptor was administered at the time of injury, collagen I mRNA in stellate cells from the injured liver was 26% of that from animals receiving control IgG (P < 0.0002); when soluble receptor was given after injury induction, collagen I expression was 35% of that in control stellate cells (P < 0.0001). By quantitative histochemistry, hepatic fibrosis in treated animals was 55% of that in controls. We conclude that soluble TGF-β receptor is an effective inhibitor of experimental fibrogenesis in vivo and merits clinical evaluation as a novel agent for controlling hepatic fibrosis in chronic liver injury.

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Septal fibrosis is a common form of hepatic fibrosis, but its etiology and pathogenesis are poorly understood. Rats infected with the helminth Capillaria hepatica constitute a good experimental model of such fibrosis. To investigate the pathogenetic contribution of the several parasitic factors involved, the following procedures were performed in rats: a) regarding the role of eggs, these were isolated and injected either into the peritoneal cavity or directly into the liver parenchyma; b) for worms alone, 15-day-old infection was treated with mebendazole, killing the parasites before oviposition started; c) for both eggs and worms, rats at the 30th day of infection were treated with either mebendazole or ivermectin. Eggs only originated focal fibrosis from cicatricial granulomas, but no septal fibrosis. Worms alone induced a mild degree of perifocal septal fibrosis. Systematized septal fibrosis of the liver, similar to that observed in the infected controls, occurred only in the rats treated with mebendazole or ivermectin, with dead worms and immature eggs in their livers. Thus, future search for fibrogenic factors associated with C. hepatica infection in rats should consider lesions with both eggs and worms.

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INTRODUCTION: Septal fibrosis of the liver regularly develops in rats infected with the nematode Capillaria hepatica. Curative treatment of the infection prevents the development of septal fibrosis when intervention occurs up to postinfection day (PID) 15, but not later. The present investigation aimed to demonstrate which parasitic factors are present when the process of septal fibrosis can no longer be prevented by curative treatment. METHODS: Wistar rats were infected with 600 embryonated eggs of C. hepatica administered by gavage and treated with ivermectin and mebendazole in separate groups at PIDs 10, 12, 15, 17 or 20. Rats from each group and their nontreated controls, were killed and examined 40 days after the end of treatment. RESULTS: Findings by PID 15 were compatible with the stage of complete maturation of infection, when worms and eggs were fully developed and a complex host-parasite multifocal necroinflammatory reaction showed greater intensity, but with no signs of septal fibrosis, which appeared from PID 17 onward. CONCLUSIONS: Since the worms spontaneously died by PID 15, not only septal fibrosis production, but also its maintenance and further development appeared dependent on the presence of eggs, which were the only parasitic factor remaining thereafter.

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Fine, long, fibrous septa were observed as a late change developing in the acinar zone III of the liver of rats experimentally infected with the helminth Capillaria hepatica. Hepatic septal fibrosis begun 30 days after inoculation of embryonated eggs into the stomach of rats and became clearly evident from the 40th day onwards. Experimental observation was undertaken for 170 days. Septal fibrosis increased progressively with time and was most marked when the parasitic nodules formed around larvae, disintegrating worms and eggs were involving. Septal fibrosis of the liver has not been previously recognized as a manifestation of hepatic capillariasis. The presence of sequestered parasite antigens, probably being slowly released within the liver, appears to be a major factor in the pathogenesis of hepatic septal fibrosis observed in rats with C. hepatica infection.

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Interferon-alpha is used in antiviral therapy in humans, mainly for viral hepatitis B and C. An anti-fibrotic effect of interferon has been postulated even in the absence of anti-viral response, which suggests that interferon directly inhibits fibrogenesis. Rats infected with the helminth Capillaria hepatica regularly develop diffuse septal fibrosis of the liver, which terminates in cirrhosis 40 days after inoculation. The aim of this study was to test the anti-fibrotic effect of interferon in this experimental model. Evaluation of fibrosis was made by three separate methods: semi-quantitative histology, computerized morphometry and hydroxyproline measurements. Treatment with interferon-alpha proved to inhibit the development of fibrosis in this model, especially when doses of 500,000 and 800,000 IU were used for 60 days. Besides confirming the anti-fibrotic potential of interferon-alpha on a non-viral new experimental model of hepatic fibrosis, a clear-cut dose-dependent effect was observed.

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Systhematized septal fibrosis of the liver can be induced in rats either by repeated intraperitoneal injections of pig-serum or by Capillaria hepatica infection. The relationship between these two etiological factors, as far as hepatic fibrosis is concerned, is not known, and present investigation attempts to investigate it. C. hepatica-induced septal fibrosis of the liver was considerably inhibited in rats previously rendered tolerant to pig-serum. Pig-serum-tolerant rats developed antibodies against pig-serum when infected with C. hepatica, but this did not happen when the infection occurred in normal rats. On the other hand, anti-C. hepatica antibodies failed to recognize any epitope in pig-serum, by Western blot. However, no evidence of an immunological cross reactivity was found, at least at the humoral level. Alternatively, cell-mediated mechanisms may be involved, and further investigations are warranted.

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Rats infected with the helminth Capillaria hepatica regularly develop septal fibrosis of the liver similar to that induced by repeated ip injections of pig serum. Fibrosis starts when the focal parasitic lesions begin to show signs of resorption, thus suggesting an immunologically mediated pathogenesis of this fibrosis. To explore this possibility, the development of C. hepatica-related hepatic fibrosis was observed in rats exposed to worm antigens from the first neonatal day onward. Wistar rats (150 g) were either injected ip with an extract of C. hepatica eggs (protein concentration: 1 mg/ml) or received immature eggs by gavage from the first neonatal day until adult life and were then infected with 500 embryonated eggs. Changes were monitored on the basis of serum levels of anti-worm antibodies and hepatic histopathology. Rats submitted to immunological oral tolerance markedly suppressed C. hepatica-related serum antibodies and septal fibrosis of the liver when infected with the helminth later on. Tolerance trials with ip injections of worm antigens gave essentially negative results. The partial suppression of septal fibrosis of the liver after the induction of immunological tolerance to C. hepatica antigens in rats indicates an immunological basis for the fibrosis and emphasizes the importance of immunological factors in the pathogenesis of hepatic fibrosis.

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The vitronectin receptor integrin alphavbeta3 promotes angiogenesis by mediating migration and proliferation of endothelial cells, but also drives fibrogenic activation of hepatic stellate cells (HSCs) in vitro. Expecting antifibrotic synergism, we studied the effect of alphavbeta3 inhibition in two in vivo models of liver fibrogenesis. Liver fibrosis was induced in rats by way of bile duct ligation (BDL) for 6 weeks or thioacetamide (TAA) injections for 12 weeks. A specific alphavbeta3 (alphavbeta5) inhibitor (Cilengitide) was given intraperitoneally twice daily at 15 mg/kg during BDL or after TAA administration. Liver collagen was determined as hydroxyproline, and gene expression was quantified by way of quantitative polymerase chain reaction. Liver angiogenesis, macrophage infiltration, and hypoxia were assessed by way of CD31, CD68 and hypoxia-inducible factor-1alpha immunostaining. Cilengitide decreased overall vessel formation. This was significant in portal areas of BDL and septal areas of TAA fibrotic rats and was associated with a significant increase of liver collagen by 31% (BDL) and 27% (TAA), and up-regulation of profibrogenic genes and matrix metalloproteinase-13. Treatment increased gamma glutamyl transpeptidase in both models, while other serum markers remained unchanged. alphavbeta3 inhibition resulted in mild liver hypoxia, as evidenced by up-regulation of hypoxia-inducible genes. Liver infiltration by macrophages/Kupffer cells was not affected, although increases in tumor necrosis factor alpha, interleukin-18, and cyclooxygenase-2 messenger RNA indicated modest macrophage activation. CONCLUSION: Specific inhibition of integrin alphavbeta3 (alphavbeta5) in vivo decreased angiogenesis but worsened biliary (BDL) and septal (TAA) fibrosis, despite its antifibrogenic effect on HSCs in vitro. Angiogenesis inhibitors should be used with caution in patients with hepatic fibrosis.

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Hepatosplenic schistosomiasis was the first human disease in which the possibility of extensive long standing hepatic fibrosis being degraded and removed has been demonstrated. When such changes occurred, the main signs of portal hypertension (splenomegaly, esophageal varices) progressively disappeared, implying that a profound vascular remodeling was concomitantly occurring. Hepatic vascular alterations associated with advanced schistosomiasis have already been investigated. Obstruction of the intrahepatic portal vein branches, plus marked angiogenesis and compensatory hyperplasia and hypertrophy of the arterial tree are the main changes present. However, there are no data revealing how these vascular changes behave during the process of fibrosis regression. Here the mouse model of pipestem fibrosis was used in an investigation about these vascular alterations during the course of the infection, and also after treatment and cure of the disease. Animals representing the two polar hepatic forms of the infection were included: (1) "isolated granulomas" characterized by isolated periovular granulomas sparsely distributed throughout the hepatica parenchyma; and (2) 'pipestem fibrosis' with periovular granulomas and fibrosis being concentrated within portal spaces, before and after treatment, were studied by means of histological and vascular injection-corrosion techniques. Instances of widespread portal vein obstruction of several types were commonly found in the livers of the untreated animals. These obstructive lesions were soon repaired, and completely disappeared four months following specific treatment of schistosomiasis. Treatment was accomplished by the simultaneous administration of praziquantel and oxamniquine. The most impressive results were revealed by the technique of injection of colored masses into the portal system, followed by corrosion in strong acid. The vascular lesions of non-treated pipestem fibrosis were represented in the plastic casts by considerable diminution of the fine peripheral portal vein radicles, plus dilatation of periportal collaterals. Four months after treatment, this last picture appeared replaced by tufts of newly interwoven vessels formed along the main portal vein branches, disclosing a strong angiomatoid reparative change. Understanding about the cellular elements at play during fibro-vascular repairing changes of hepatic schistosomiais represents a matter of considerable scientific and conceptual importance. At present time one may only speculate about the participation of some type of natural stem-cell capable of restoring the diseased liver back to normal once the cause of the disorder has been eliminated.

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Hepatic fibrosis in patients with non-alcoholic fatty liver disease is associated with progression of the disease. In the present study, we analyzed the discriminative ability of serum laminin, type IV collagen and hyaluronan levels to predict the presence of fibrosis in these patients. In this preliminary report, we studied 30 overweight patients divided into two groups according to the absence (group I, N = 19) or presence (group II, N = 11) of fibrosis in a liver biopsy. Triglycerides, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltranspeptidade, hyaluronan (noncompetitive fluoroassay), type IV collagen, and laminin (ELISA) were determined. Group II presented significantly higher mean laminin, hyaluronan, type IV collagen, and aspartate aminotransferase values, which were due to the correlation between these parameters and the stage of fibrosis in the biopsy (Spearman's correlation coefficient, rS = 0.65, 0.62, 0.53, and 0.49, respectively). Analysis of the ROC curve showed that laminin values >282 ng/ml were those with the best diagnostic performance, with 87% accuracy. Association of laminin with type IV collagen showed improvement in the positive predictive value (100%), but with reduction in diagnostic sensitivity (64%). When compared with the criteria of Ratziu et al. [Gastroenterology (2000) 118: 1117-1123] for the diagnosis of septal fibrosis, laminin values presented a better diagnostic accuracy (83 vs 70%). Determination of extracellular matrix components in serum, especially of laminin, may identify patients with non-alcoholic fatty liver disease and fibrosis and these components may be used as indicators for liver biopsy in these patients.