Hepatitis C: an update.

Hepatitis C virus (HCV) infection is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. While current therapeutic options for hepatitis C are limited, recent progress in the understanding of the biology of HCV led to the identification of novel targets for antiviral intervention. In addition, molecular and immunotherapeutic strategies to inhibit HCV replication or gene expression and to enhance the cellular immune response against HCV are being explored. These and other novel antiviral strategies may eventually complement existing therapeutic modalities. Here, we briefly review current concepts of the epidemiology, molecular virology, pathogenesis, natural history, diagnosis, therapy, and prevention of hepatitis C

Hepatitis E virus RNA-dependent RNA polymerase is involved in RNA replication and infectious particle production.

Hepatitis E virus (HEV) is one of the most common causes of acute hepatitis worldwide. Its positive-strand RNA genome encodes three open reading frames (ORF). ORF1 is translated into a large protein composed of multiple domains and is known as the viral replicase. The RNA-dependent RNA polymerase (RDRP) domain is responsible for the synthesis of viral RNA. Here, we identified a highly conserved α-helix located in the RDRP thumb subdomain. Nuclear magnetic resonance demonstrated an amphipathic α-helix extending from amino acids 1628 to 1644 of the ORF1 protein. Functional analyses revealed a dual role of this helix in HEV RNA replication and virus production, including assembly and release. Mutations on the hydrophobic side of the amphipathic α-helix impaired RNA replication and resulted in the selection of a second-site compensatory change in the RDRP palm subdomain. Other mutations enhanced RNA replication but impaired virus assembly and/or release. Structure-function analyses identified a conserved amphipathic α-helix in the thumb subdomain of the HEV RDRP with a dual role in viral RNA replication and infectious particle production. This study provides structural insights into a key segment of the ORF1 protein and describes the successful use of reverse genetics in HEV, revealing functional interactions between the RDRP thumb and palm subdomains. On a broader scale, it demonstrates that the HEV replicase, similar to those of other positive-strand RNA viruses, is also involved in virus production

Biomarkers of liver dysfunction correlate with a prothrombotic and not with a prohaemorrhagic profile in patients with cirrhosis.

Different liver dysfunction biomarkers are used to assess the bleeding risk of patients with cirrhosis, either as such or included in bleeding risk assessment scores. Since the current model of coagulation in patients with cirrhosis describes a procoagulant tendency with increasing severity according to Child-Pugh stage, we decided to investigate the relation between liver dysfunction biomarkers and thrombin generation. Our aim was to verify their adequacy for bleeding risk assessment. We performed a prospective single-centre study including 260 patients with liver cirrhosis. Thrombin generation was measured using ST Genesia® Thrombin Generation System without and with thrombomodulin in order to assess the role of proteins C and S. Relations between thrombin generation and Child-Pugh/model for end-stage liver disease (MELD) scores, prothrombin time (PT)/international normalised ratio (INR), activated partial thromboplastin time (aPTT), factor V activity, albumin, and total bilirubin were assessed. Thrombomodulin-mediated inhibition of thrombin generation was significantly decreased in patients with liver cirrhosis compared with healthy donors (p <0.0001) and in Child-Pugh B and C compared with A (p <0.0001 [A-B], 0.4515 [B-C], <0.0001 [A-C]). Thrombomodulin-mediated inhibition significantly decreased with increasing PT/INR, aPTT, and total bilirubin levels and with decreasing factor V activity and albumin levels. Worsening liver dysfunction biomarkers reflect an increasing prothrombotic profile in patients with liver cirrhosis. In particular, prolonged PT/INR and aPTT as well as decreasing factor V activity are related to an increasing thrombotic risk and not to an increasing bleeding risk. These parameters should not be used to assess bleeding risk due to haemostatic anomalies in patients with liver cirrhosis. Alternative biomarkers for bleeding risk assessment in patients with liver cirrhosis need to be developed. We demonstrate that the laboratory parameters used to assess bleeding risk of patients with liver disease, e.g. prothrombin time/international normalised ratio (PT/INR) and activated partial thromboplastin time (aPTT), are inadequate for this purpose because they are correlated with a prothrombotic coagulation profile. In this article, we highlight the need for alternative parameters to assess bleeding risk in patients with liver disease

Sofosbuvir and ribavirin before liver re-transplantation for graft failure due to recurrent hepatitis C: a case report.

BACKGROUND: Recurrent hepatitis C virus infection after liver transplantation is associated with reduced graft and patient survival. Re-transplantation for graft failure due to recurrent hepatitis C is controversial and not performed in all centers. CASE PRESENTATION: We describe a 54-year-old patient with hepatitis C virus genotype 1b infection and a null response to pegylated interferon-α and ribavirin who developed decompensated graft cirrhosis 6 years after a first liver transplantation. Treatment with sofosbuvir and ribavirin allowed for rapid negativation of serum HCV RNA and was well tolerated despite advanced liver and moderate renal dysfunction. Therapeutic drug monitoring did not reveal any clinically significant drug-drug interactions. Despite virological response, the patient remained severely decompensated and re-transplantation was performed after 46 days of undetectable serum HCV RNA. The patient is doing well 12 months after his second liver transplantation and remains free of hepatitis C virus. CONCLUSIONS: The use of directly acting antivirals may allow for successful liver re-transplantation for recipients who remain decompensated despite virological response and is likely to improve the outcome of liver re-transplantation for end-stage recurrent hepatitis C

Demographics and outcomes of hepatitis B and D: A 10-year retrospective analysis in a Swiss tertiary referral center.

Hepatitis B virus (HBV) is a major global health challenge with approximately 250-350 million chronically infected individuals. An improved understanding of the demographic features and outcomes of chronic HBV infection and hepatitis D virus (HDV) infection in low-endemic areas may improve prevention, early identification and management both at individual and community levels. Here, we retrospectively analyzed the demographic and clinical characteristics, treatment rates and outcomes of adult patients with chronic HBV infection with or without HDV coinfection examined at Lausanne University Hospital, Switzerland over a 10-year period. We analyzed the medical records of all adult patients with chronic HBV and HDV infection examined in our center between 2007 and 2016. Liver-related outcome was defined as the occurrence of cirrhosis, hepatocellular carcinoma, liver transplantation or liver-related death. Analyses were performed using logistic regression and results were reported as odds ratio (OR) and 95% confidence interval (CI). Of 672 consecutive patients, 421 (62.6%) were male, median age was 36 years (interquartile range, 28-46 years), and 233 (34.7%) were of African origin. The prevalence of HDV coinfection was 7.1% and the proportion of anti-HDV-positive patients with detectable HDV RNA was 70.0%. In multivariate analysis, HDV coinfection was the strongest predictor for liver-related outcome (OR 6.06, 95% CI 2.93-12.54, p<0.001), followed by HBeAg positivity (OR 2.47, 95% CI 1.30-4.69, p = 0.006), age (OR per 10-year increase 2.03, 95% CI 1.63-2.52, p<0.001) and sex (OR for female 0.39, 95% CI 0.22-0.71, p = 0.002). The predictive accuracy of the multivariate model was high (receiver operator characteristic area under the curve 0.81). This retrospective study underscores the importance of migration in the epidemiology of chronic hepatitis B in low-endemic areas. HDV coinfection, HBeAg positivity and age predicted liver-related outcomes while female sex had a protective effect

Sofosbuvir add-on to ribavirin for chronic hepatitis E in a cirrhotic liver transplant recipient: a case report.

Chronic hepatitis E represents an emerging challenge in organ transplantation, as there are currently no established treatment options for patients who fail to clear hepatitis E virus (HEV) following reduction of immunosuppressive therapy and/or treatment with ribavirin. Sofosbuvir has shown antiviral activity against HEV in vitro but clinical utility in vivo is unknown. We describe a 57-year-old liver transplant recipient with decompensated graft cirrhosis due to chronic hepatitis E. Reduction of immunosuppressive treatment as well ribavirin alone for 4 months did not result in viral clearance. Add-on of sofosbuvir for 6 months was associated with HEV RNA becoming undetectable in plasma. However, sustained viral clearance could not be achieved. Sofosbuvir may have some antiviral activity against HEV when added to ribavirin. However, this did not suffice to yield sustained viral clearance. Our well-characterized observation emphasizes the need for new treatment options to cure chronic hepatitis E in the setting of organ transplantation

Consequences of the multipatient use of a single-patient capillary blood sampling device (CBSD)

Introduction/objectives: Multipatient use of a single-patient CBSD occurred inan outpatient clinic during 4 to 16 months before itsnotification. We looked for transmission of blood-bornepathogens among exposed patients.Methods: Exposed patients underwent serology testing for HBV,HCV and HIV. Patients with isolated anti-HBc receivedone dose of hepatitis B vaccine to look for a memoryimmune response. Possible transmissions were investigatedby mapping visits and sequencing of the viral genomeif needed.Results: Of 280 exposed patients, 9 had died without suspicionof blood-borne infection, 3 could not be tested, and 5declined investigations. Among the 263 (93%) testedpatients, 218 (83%) had negative results. We confirmeda known history of HCV infection in 6 patients (1 coinfectedby HIV), and also identified resolved HBVinfection in 37 patients, of whom 18 were alreadyknown. 2 patients were found to have a previouslyunknown HCV infection. According to the time elapsedfrom the closest previous visit of a HCV-infected potentialsource patient, we could rule out nosocomial transmissionin one case (14 weeks) but not in the other (1day). In the latter, however, transmission was deemedvery unlikely by 2 reference centers based on thesequences of the E1 and HVR1 regions of the virus.Conclusion: We did not identify any transmission of blood-bornepathogens in 263 patients exposed to a single-patientCBSD, despite the presence of potential source cases.Change of needle and disinfection of the device betweenpatients may have contributed to this outcome.Although we cannot exclude transmission of HBV, previousacquisition in endemic countries is a more likelyexplanation in this multi-national population

Targeting Endoplasmic Reticulum and/or Mitochondrial Ca2+ Fluxes as Therapeutic Strategy for HCV Infection.

Chronic hepatitis C is characterized by metabolic disorders and by a microenvironment in the liver dominated by oxidative stress, inflammation and regeneration processes that can in the long term lead to liver cirrhosis and hepatocellular carcinoma. Several lines of evidence suggest that mitochondrial dysfunctions play a central role in these processes. However, how these dysfunctions are induced by the virus and whether they play a role in disease progression and neoplastic transformation remains to be determined. Most javax.xml.bind.JAXBElement@5b15fc8d studies performed so far have shown that several of the hepatitis C virus (HCV) proteins also localize to mitochondria, but the consequences of these interactions on mitochondrial functions remain contradictory and need to be confirmed in the context of productively replicating virus and physiologically relevant javax.xml.bind.JAXBElement@5e13485c and javax.xml.bind.JAXBElement@73aee95e model systems. In the past decade we have been proposing a temporal sequence of events in the HCV-infected cell whereby the primary alteration is localized at the mitochondria-associated ER membranes and causes release of Ca javax.xml.bind.JAXBElement@476155bf from the ER, followed by uptake into mitochondria. This ensues successive mitochondrial dysfunction leading to the generation of reactive oxygen and nitrogen species and a progressive metabolic adaptive response consisting in decreased oxidative phosphorylation and enhanced aerobic glycolysis and lipogenesis. Here we resume the major results provided by our group in the context of HCV-mediated alterations of the cellular inter-compartmental calcium flux homeostasis and present new evidence suggesting targeting of ER and/or mitochondrial calcium transporters as a novel therapeutic strategy