Hepatitis C viral infection in liver transplant recipients

Megamitochondria formation in hepatocytes of patient with chronic hepatitis C - a case report

Although chronic hepatitis C virus (HCV) infection affect 185 million people world-wide, pathomechanism of liver damage is still unclear. Electron microscopy can reveal liver injury in very early stage and help understanding the mechanisms that is crucial in the pathogenesis of chronic hepatitis C. We present the morphological changes in the liver of HCV infected 24-year-old female patient, using light and transmission electron microscopy. Examination by TEM revealed wide range of specific subcellular abnormalities in hepatocellular ultrastructure. The most common observed changes were ring-shaped nuclei with intranuclear inclusion, megamitochondria, and “membranous web” structures – the hallmark of RNA-viruses infection.

Peromyscus as a model system for human hepatitis C: An opportunity to advance our understanding of a complex host parasite system

Worldwide, there are 185 million people infected with hepatitis C virus and approximately 350,000 people die each year from hepatitis C associated liver diseases. Human hepatitis C research has been hampered by the lack of an appropriate in vivo model system. Most of the in vivo research has been conducted on chimpanzees, which is complicated by ethical concerns, small sample sizes, high costs, and genetic heterogeneity. The house mouse system has led to greater understanding of a wide variety of human pathogens, but it is unreasonable to expect Mus musculus to be a good model system for every human pathogen. Alternative animal models can be developed in these cases. Ferrets (influenza), cotton rats (human respiratory virus), and woodchucks (hepatitis B) are all alternative models that have led to a greater understanding of human pathogens. Rodent models are tractable, genetically amenable and inbred and outbred strains can provide homogeneity in results. Recently, a rodent homolog of hepatitis C was discovered and isolated from the liver of a Peromyscus maniculatus. This represents the first small mammal (mouse) model system for human hepatitis C and it offers great potential to contribute to our understanding and ultimately aid in our efforts to combat this serious public health concern. Peromyscus are available commercially and can be used to inform questions about the origin, transmission, persistence, pathology, and rational treatment of hepatitis C. Here, we provide a disease ecologist's overview of this new virus and some suggestions for useful future experiments.

Recurrent Hepatitis C in Liver Allografts: Early Histologic Indicators

Our purpose was to establish the earliest histologic parameters of acute hepatitis that correlated with recurrent hepatitis C virus (HCV) infection in liver allografts. Histologic reviews of posttransplant liver biopsies from eight patients with pretransplant chronic HCV (group I) and eight with pretransplant non-HCV liver disease (group II) were performed and correlated with concurrent or subsequent presence or absence of HCV-RNA by polymerase chain reaction (PCR). Six of eight group I patients developed HCV-RNA positivity in liver and serum. Of the histologic parameters studied, the presence of Kupffer cell hyperplasia, spotty hepatocellular necrosis (acidophil bodies), or both, correlated the most with the earliest diagnosis of acute recurrent hepatitis. The postoperative time period for the earliest diagnosis of recurrent HCV was variable (34 to 123 days). These early indicators and the time of their appearance were not predictive of the course of the disease process or the final outcome of the patient. The recurrence rate of HCV infection in liver allografts is high. The presence of Kupffer cell hyperplasia and diffusely scattered acidophil bodies are reliable, early histologic indicators of an acute hepatitic process.

Management of post liver transplantation recurrent hepatitis C infection with directly acting antiviral drugs: a review

Recurrent HCV infection (rHCV) of the liver allograft following transplantation is universal and is associated with poor graft and patient survival in comparison with other indications. Treatment of rHCV infection in the previous era with pegylated interferon and ribavirin was associated with low sustained virological response (SVR) due to poor tolerability, adverse events and graft rejection. Recently, directly acting antiviral drugs (DAA) have been approved for the treatment of hepatitis C infection and a number of clinical trials have been conducted across various centers in the management of rHCV infection of the graft. In this review we discuss about recent studies that have emerged on the use of NS5b polymerase inhibitor, sofosbuvir in combination with second generation protease inhibitor, simeprevir, fixed dose ledipasvir or daclatasvir with or without ribavirin in the treatment of post transplant rHCV infection.

Treatment strategies for chronic hepatitis C prior to and following liver transplantation

Hepatitis C virus (HCV)-related liver disease is the leading indication for liver transplantation (LT) worldwide. However, HCV is an independent predictor of lower survival following LT, and recurrence of HCV post-LT is virtually universal. The historic standard of care during the interferon era of HCV therapy was expectant management-initiation of antiviral therapy in the setting of documented disease progression following LT. With the advent of new direct acting antiviral (DAA) therapies for HCV, the paradigm of expectant treatment for recurrent HCV infection post-LT is shifting. The safety, tolerability, and efficacy of DAAs, even among the sickest patients with advanced liver disease, enables treatment of HCV in the pre-transplant setting among LT waitlist registrants. Finally, emerging data are supportive of preemptive therapy with DAAs in liver transplant recipients as the preferred approach. Expectant management of HCV following LT can rarely be justified in the modern era of HCV therapy.

Analysis of the intrahepatic ductular reaction and progenitor cell responses in hepatitis C virus recurrence after liver transplantation

Fibrosis in livers with hepatitis C virus (HCV) recurrence after liver transplantation (LT) can be rapidly progressive, and the mechanisms underlying this process are poorly understood. In livers with HCV infections in the non-LT setting, there is a significant relationship between the development of structures known as the ductular reaction (DR), hepatic progenitor cells (HPCs), and fibrosis. This study characterizes the DR, HPCs, and fibrosis associated with HCV recurrence after LT. Immunohistochemistry and confocal microscopy were used to characterize the DR, HPC, and fibrosis in liver biopsy specimens. Key findings were confirmed in a separate, independent cohort. The initial characterization cohort had 194 biopsy samples from 105 individuals with HCV recurrence after LT. The immunophenotype, morphology, and location of the DR were consistent with an HPC origin. The DR correlated with intrahepatic fibrosis (rs  = 0.529, P < 0.001) and the number of activated hepatic stellate cells (HSCs; rs  = 0.446, P < 0.001). There was an early occurrence of hepatocyte replicative arrest as well as increased hepatocyte proliferation that correlated with the DR (rs  = 0.295, P < 0.001). Replicative arrest preceded hepatocyte proliferation in early-stage injury. Hepatocyte proliferation decreased with advanced fibrosis; in contrast, the extent of the DR and the number of activated HSCs continued to increase. In the second cohort of 37 individuals, the DR and the number of HPCs similarly correlated with fibrosis and inflammation after LT. In conclusion, this is the first characterization of the DR in HCV-associated liver injury after LT. There was a significant correlation between the DR and the development of progressive fibrosis in HCV recurrence. These results suggest a pivotal role for both the DR and the HPC responses in the aggressive fibrosis seen with HCV recurrence after LT.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Intragraft transcriptome level of CXCL9 as biomarker of acute cellular rejection after liver transplantation

BACKGROUND

Liver transplantation has been a life-saving and well-established treatment for acute liver failure and various end-stage liver diseases. However, acute cellular rejection (ACR) is one of the key factors that determine long-term graft function and survival after liver transplantation, and there are still no specific biomarkers available to monitor the alloimmune response. The aim of the present study was to identify molecular biomarkers for ACR in liver allograft.

METHODS

We analyzed the gene expression profile using an oligonucleotide microarray covering 44,000 human probes in 35 liver biopsy samples after living donor liver transplant, which consisted of 13 samples with ACR (ACR group; moderate/mild, 6/7), 13 samples with other dysfunctions (non-ACR group; recurrent hepatitis C / ischemia/reperfusion injury (IRI)/ nonspecific inflammation / small-for-size syndrome, 5/4/3/1), and 9 samples without liver dysfunction (protocol group). We selected 113 informative genes based on microarray results and adopted the network analysis to visualize key modulators in ACR. We selected 6 modulators (CXCL9, GZMB, CCL19, GBP2, LAIR1, and CDC25A) and confirmed the reproducibility in 23 independent biopsy samples and investigated the response to the rejection treatment in sequential samples.

RESULTS

Network analysis revealed the top three subnetworks, which had NF-κB, MAPK, and IFNG as central hubs. Among selected modulators, intragraft expression levels of CXCL9 mRNA was most upregulated and sensitive to alloimmune status.

CONCLUSION

Intragraft CXCL9 mRNA has a functionally important role in T-cell activation in liver allograft and serves as biomarker for ACR.

NASPGHAN practice guidelines: Diagnosis and management of hepatitis C infection in infants, children, and adolescents

Hepatitis C virus (HCV) is an RNA virus that affects >180 million individuals worldwide with a high propensity for chronic infection. Children with HCV infection differ from adults in several ways including some modes of transmission, rates of clearance, progression of fibrosis, and the duration of potential chronic infection when acquired at birth. Since the discovery of HCV in 1989, there have been significant advances in the understanding of the virology and natural history of chronic HCV infection in children. In addition, there are now several treatment options for children with chronic hepatitis C infection and many new therapies on the horizon. As a consequence, the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition brought together experts in pediatric hepatology to review the available data in children and provide clinicians with approaches to the diagnosis, management, and prevention of HCV infection in children and adolescents. The guideline details the epidemiology and natural history of HCV infection in children, the diagnostic workup, monitoring and treatment of disease, and provides an update on future treatment options and areas of research.

Liver biopsy for histological assessment: The case in favor

Liver biopsy (LB) is the gold standard method for assessment of liver histology. It provides valuable, otherwise unobtainable information, regarding the degree of fibrosis, parenchymal integrity, degree and pattern of inflammation, bile duct status and deposition of materials and minerals in the liver. This information provides immense help in the diagnosis and prognostication of a variety of liver diseases. With careful selection of patients, and performance of the procedure appropriately, the complications become exceptionally rare in current clinical practice. Furthermore, the limitations of sampling error and inter-/intra-observer variability may be avoided by obtaining adequate tissue specimen and having it reviewed by an experienced liver pathologist. Current noninvasive tools are unqualified to replace LB in clinical practice in the face of specific limitations for each tool, compounded by a poorer performance towards the assessment of the degree of liver fibrosis, particularly for intermediate stages.

Differential transcriptome patterns for acute cellular rejection in recipients with recurrent hepatitis C after liver transplantation

Histopathological evaluation of the liver via biopsy remains the standard procedure for the diagnosis of both acute cellular rejection (ACR) and recurrent hepatitis C (RHC) after liver transplantation. Nevertheless, it is often difficult to diagnose ACR in hepatitis C virus-positive recipients because of changes in common and overlapping with RHC. The aim of this study was to identify potential target genes for ACR in recipients with RHC. We analyzed 22 liver biopsy samples obtained from 21 hepatitis C virus-positive recipients. The clinicopathological diagnosis based on biopsy examination was ACR-predominant with superimposed RHC in 9 samples (ACR group) and RHC without ACR (non-ACR group) in 13. Using oligonucleotide microarrays, we compared the transcriptional changes in the 2 groups and selected 2206 genes that were significantly modulated in ACR. We analyzed the regulatory networks in ACR with Ingenuity Pathway Analysis software, and we confirmed with quantitative real-time polymerase chain reaction the reproducibility of caspase 8, apoptosis-related cysteine peptidase and bone morphogenetic protein 2 up-regulation in another group of validation samples, representing 2 genes from the core network as the target genes for ACR. Our results demonstrated novel transcriptome patterns for ACR with concurrent RHC that were distinct from those of recipients with only RHC, suggesting that gene expression profiling may be useful in the diagnosis of ACR in recipients with hepatitis C.

Evolution of hepatitis C virus in liver allografts

1. Hepatitis C virus (HCV) RNA+ liver allograft recipients invariably reinfect the liver allograft within hours after transplantation, and the majority (>70%) develop chronic hepatitis. The rate at which these patients experience progression to cirrhosis and the overall percentage are significantly increased in comparison with HCV infection in the nontransplant setting. 2. Core needle biopsy evaluation is used to establish the diagnosis of recurrent HCV, which can be difficult to distinguish from acute cellular rejection and other causes of allograft dysfunction. In the vast majority of cases, however, distinguishing recurrent HCV from other posttransplant syndromes is reliably achieved by a careful examination of hematoxylin and eosin-stained sections and correlation with clinical and serological data. 3. Recurrent HCV often coexists with other causes of liver allograft dysfunction, and the determination of the most important cause of injury and whether other causes of injury are present is important. Included are residual changes of preservation/reperfusion injury, biliary sludging/structuring, acute cellular and chronic rejection, and autoimmune hepatitis. 4. The complex interplay between immunosuppression management, viral replication, and the recipient immune system results in distinct patterns of recurrent chronic HCV in the liver allograft: (1) conventional or usual acute and chronic HCV, which resembles that seen in the general population with HCV; (2) fibrosing cholestatic hepatitis; and (3) plasma cell-rich HCV, which might represent a variant of, or overlap with, autoimmune hepatitis and rejection. 5. The variable but usually hastened histopathological progression toward cirrhosis in HCV+ allografts is similar to that seen in the nontransplant setting, but in allografts, the overall severity of lymphocytic inflammation is less, and ductular reactions, stellate cell activation, and subsinusoidal fibrosis are accentuated. Hepatic stressors and causes of an impaired ability of hepatocytes to replicate include persistently high levels of viral replication, HCV-specific CD4+ T responses, advanced donor age, high levels or rapid withdrawal of immunosuppression, and coexistent liver damage from preservation/reperfusion injury, biliary structuring, or coexistent cytomegalovirus or herpes 6 viral infection. 6. Immunological effector mechanisms involved in the rejection and control of HCV replication/HCV elimination show significant overlap. Patients with very high levels of HCV RNA rarely show significant clinically significant acute or chronic rejection, whereas their occurrence is frequently associated with very low levels or clearance of HCV RNA. Studying the evolution from recurrent HCV to acute rejection in patients treated with interferon and/or weaned from immunosuppression might provide valuable insights into the relationship between these 2 processes as well as liver allograft acceptance.

Immunohistochemical staining of liver grafts with a monoclonal antibody against HCV-Envelope 2 for recurrent hepatitis C after living donor liver transplantation

AIM

We evaluated the expression of hepatitis C virus (HCV) antigen on liver grafts by immunohistochemical staining (IHS) using IG222 monoclonal antibody (mAb) against HCV-envelope 2 (E2).

METHODS

The study material was 84 liver biopsy specimens obtained from 28 patients who underwent living donor liver transplantation (LDLT) for HCV infection. The biopsy samples were examined histopathologically, and by IHS using IG222 mAb against HCV-E2. Serum HCV-RNA level was measured in all patients. The IHS grades were compared among the three groups classified according to the time elapsed from LDLT (at 1-30, 31-179 and > or =180 days post-LDLT) and among four post-transplant conditions, including acute cellular rejection (ACR).

RESULTS

Immunoreactivity to IG222 was detected in 78.6% of the specimens obtained during the first month after LDLT, and there were no significant differences on the IHS grades between the three groups classified according to the time elapsed from LDLT. The IHS grades were significantly stronger in definite recurrent HCV (n = 12) and probable recurrent HCV (n = 7) than in definite ACR (n = 7) and other complications (n = 8). There were no significant differences in serum HCV-RNA levels among the four post-transplant conditions. There was no significant correlation between the IHS grades using IG222 mAb and serum HCV-RNA levels when data of 84 liver biopsy specimens were analyzed.

CONCLUSIONS

Constant HCV-E2 expression was observed in liver biopsy specimens obtained 1 month or longer. The strong HCV-E2 expression on liver grafts were associated with recurrent hepatitis C after LDLT, but the serum HCV-RNA levels were not.

Serum autoantibodies against cytochrome P450 2E1 (CYP2E1) predict severity of necroinflammation of recurrent hepatitis C

We previously reported that autoantibodies against cytochrome P4502E1 (CYP2E1) are frequent in patients with chronic hepatitis C. As autoimmune reactions are increasingly detected after orthotopic liver transplantation (OLT), this study investigates prevalence and significance of anti-CYP2E1 autoantibodies in 46 patients with post-OLT recurrent hepatitis C. IgG against recombinant human CYP2E1 above the control threshold was detected in 19 out 46 (41%) sera collected immediately before OLT and in 15 out 46 (33%) sera collected at the time of the 12 months follow-up liver biopsy. Although anti-CYP2E1 reactivity was not modified by OLT, the patients with persistently elevated anti-CYP2E1 IgG (n = 12; 26%) showed significantly higher prevalence of recurrent hepatitis with severe necroinflammation and fibrosis than those persistently negative or positive only either before or after OLT. Moreover, the probability of developing severe necroinflammation was significantly higher in persistently anti-CYP2E1-positive subjects. Multivariate regression and Cox analysis confirmed that the persistence of anti-CYP2E1 IgG, together with a history of acute cellular rejection and donor age >50 years, was an independent risk factor for developing recurrent hepatitis C with severe necroinflammation. We propose that autoimmune reactions involving CYP2E1 might contribute to hepatic damage in a subgroup of transplanted patients with recurrent hepatitis C.

Seeking beyond rejection: an update on the differential diagnosis and a practical approach to liver allograft biopsy interpretation

Pathologic evaluation of liver allograft biopsies plays an integral role in the management of patients after liver transplantation. This review summarizes the clinical context and classical histology of different types of allograft rejection and also the common entities that enter the differential diagnosis of allograft rejection, and provides practical approaches to liver allograft biopsy interpretation. In addition, some of the new developments in the field of liver transplant pathology are updated. The purpose of this review is to provide guidance for pathologists interpreting liver allograft biopsies, particularly those interested in developing expertise in the field of liver transplant pathology.

Does interferon use prior to liver transplant influence hepatitis C outcomes following transplantation?

BACKGROUND

The most frequent reason for orthotopic liver transplantation (OLT) in the United States is due to complications of hepatitis C (HCV). Recent reports have shown decreased survival for HCV after OLT. Of note, the use of interferon (IFN) products has become wide spread with the majority of HCV patients being treated before transplant.

AIM

To review the outcomes of HCV patients who have received IFN products before liver transplant compared with HCV patients those who have never received IFN.

METHOD

Single-center, retrospective review of patients transplanted for HCV since December 1998 (n=131). Primary endpoint is the effect of IFN exposure before transplant on posttransplant outcomes.

RESULTS

Patients receiving before transplant (pre-IFN group; n=45) had a more aggressive recurrence of HCV with earlier recurrence (181.1+/-236 days vs. 303.4+/- 327 days; P=0.031), frequency of recurrence [41/45 (91.1%) vs. 62/86 (72.1%); P=0.013], and 1-year recurrence free survival [20% (+/-0.06) vs. 48.2% (+/-0.05); P=0.005]. Survival difference was noted in the pre-IFN group at 1 year and 3 years [79.7% (+/-0.06) vs. 90.5% (+/-0.03); 65.7 (+/-0.08) vs. 75.9% (+/-0.05); P=0.05] when compared with patients not receiving IFN (n=86) before transplant.

CONCLUSIONS

Based on this study, interferon use before transplant for the HCV patient indicates poor outcomes After OLT. Because of the increasing numbers of HCV patients coming to transplant, validation of these results should be of utmost importance.

Histology of symptomatic acute hepatitis C infection in immunocompetent adults

Acute hepatitis C in immunocompetent individuals is rarely symptomatic and rarely biopsied. Thus, the histologic descriptions of acute hepatitis C remain limited. The histology of 5 cases of acute hepatitis C in adults were studied by selecting cases from the consult and surgical pathology files of a single institution. The 5 individuals, 3 males and 2 females, had an average age at biopsy of 50+/-17 years. They presented with jaundice and other nonspecific abdominal symptoms. The time interval from clinical presentation to biopsy ranged from 2 to 18 weeks. The average alanine aminotransferase/aspartate aminotransferase/alkaline phosphatase at the time of biopsy was 308/73/85 U/L. The average total bilirubin was 5.2 mg/dL. Each individual had a single liver biopsy. The histologic findings of the 2 cases biopsied in close temporal proximity to the initial clinical presentation showed similar histologic findings of mixed portal infiltrates with lymphocytes and neutrophils along with bile ductular proliferation that raised the possibility of down stream biliary tract disease. The lobules showed canalicular cholestasis and mild to moderate inflammation. In the third and fourth case, obtained 8 weeks after presentation, the biopsies showed mild to moderate portal and lobular lymphocytic inflammation, findings that were also present in the last case, obtained 18 weeks after presentation. In conclusion, early after acute hepatitis C viral infection, biopsies can have a cholestatic pattern whereas later biopsies tend to show mild nonspecific portal and lobular lymphocytic inflammation. Proper histologic diagnosis can be aided by an awareness of the various histologic findings, which vary depending on the time interval from clinical symptoms to biopsy.

Chronic ductopenic rejection in patients with recurrent hepatitis C virus treated with pegylated interferon alfa-2a and ribavirin

BACKGROUND

Interferon use for post liver transplantation (LT) recurrent hepatitis C (HCV) has not consistently been associated with acute cellular rejection (ACR). We examined the incidence of chronic ductopenic rejection (CR) in patients receiving pegylated interferon alfa-2a and ribavirin (PEG) to treat recurrent HCV.

METHODS

A chart review of 12 patients developing CR while receiving an escalating dose regimen of PEG with protocol liver biopsies every 6 months was conducted. Values are shown as median (range).

RESULTS

Twelve of the 70 patients treated with PEG developed CR. Median age at LT was 53 (37-63) years; immunosuppression consisted of tacrolimus or cyclosporine with prednisone. PEG was started at 3.6 (0.2-13.5) years after LT. Two patients had one episode of ACR before PEG. Four patients had first ACR while receiving PEG. CR was diagnosed after 12 (4-17) months of PEG; by then 8 patients had undetectable HCV-RNA. Tacrolimus and cyclosporine levels (ng/mL) were 7.9 (3.2-18.9) and 76 (71-93) before PEG, and 6.9 (3.7-9.7) and 130 (81-153) at CR. Six patients were treated more than 1 year with PEG; three had undetectable HCV-RNA when CR was diagnosed. Five patients are being treated for CR; one has been listed for LT; two patients were retransplanted. Five patients died as a result of sepsis partially related to CR.

CONCLUSIONS

Treatment with pegylated-interferon alpha-2a and ribavirin may trigger rapidly progressive CR in patients with therapeutic immunosuppressive trough levels, with or without first inducing ACR.

Management of hepatitis C infection after liver transplantation

Recurrent hepatitis C virus (HCV) infection after orthotopic liver transplantation (OLT) has been associated with progression to cirrhosis in approximately 20% of patients, 5 years postoperatively. Accelerated decompensation has also been noted when compared with cirrhosis in non-transplant patients. Different treatment strategies are available for recurrent HCV infection post-OLT, but efforts are hindered by the modest response rates, poor tolerability and the risk of rejection as well as graft loss. Anti-HCV immunoglobulin therapy to prevent graft infection with HCV has no established role at present but studies are ongoing. Treatment prior to transplantation in patients with decompensated cirrhosis has been evaluated but the results are too preliminary to make firm recommendations. Prophylactic interferon-based antiviral therapy in the early postoperative period to prevent graft infection was shown to have low response rates and high rates of adverse effects. Treatment of established recurrent HCV infection with combination peginterferon (pegylated interferon) and ribavirin is associated with 10-59% sustained virological response and the predictive value of a positive early virological response has been validated in the post-transplant setting. Improvement in inflammatory activity after viral eradication is well established, but fibrosis regression or stabilisation is less predictable and factors such as rejection and biliary complications may still contribute to graft loss. Most studies have initiated therapy at least 6 months postoperatively in order to optimise patient tolerance and enable the addition of ribavirin. The use of adjuvant agents to treat drug-induced neutropenia and anaemia in this population is evolving and becoming a crucial part of therapy. Determination of optimal doses of both pegylated interferon and ribavirin, and guidance on when to stop treatment, as well as improving tolerability are important steps in achieving higher response rates and minimising drug toxicity.

Inhibition of T-cell inflammatory cytokines, hepatocyte NF-kappaB signaling, and HCV infection by standardized Silymarin

BACKGROUND & AIMS

Chronic hepatitis C is a serious global medical problem necessitating effective treatment. Because standard of care with pegylated interferon plus ribavirin therapy is costly, has significant side effects, and fails to cure about half of all infections, many patients seek complementary and alternative medicine to improve their health, such as Silymarin, derived from milk thistle (Silybum marianum). Milk thistle's clinical benefits for chronic hepatitis C are unsettled due to variability in standardization of the herbal product.

METHODS

In the current study, we focused on the anti-inflammatory and antiviral properties of a standardized Silymarin extract (MK-001).

RESULTS

MK-001 inhibited expression of tumor necrosis factor-alpha in anti-CD3 stimulated human peripheral blood mononuclear cells and nuclear factor kappa B-dependent transcription in human hepatoma Huh7 cells. Moreover, MK-001 dose dependently inhibited infection of Huh7 and Huh7.5.1 cells by JFH-1 virus. MK-001 displayed both prophylactic and therapeutic effects against HCV infection, and when combined with interferon-alpha, inhibited HCV replication more than interferon-alpha alone. Commercial preparations of Silymarin also displayed antiviral activity, although the effects were not as potent as MK-001. Antiviral effects of the extract were attributable in part to induction of Stat1 phosphorylation, while interferon-independent mechanisms were suggested when the extract was biochemically fractionated by high-performance liquid chromatography. Silybin A, silybin B, and isosilybin A, isosilybin B elicited the strongest anti-NF-kappaB and anti-HCV actions. These effects were independent of MK-001-induced cytotoxicity.

CONCLUSIONS

The data indicate that Silymarin exerts anti-inflammatory and antiviral effects, and suggest that complementary and alternative medicine-based approaches may assist in the management of patients with chronic hepatitis C.

c-Kit-positive mast cells in portal tracts cannot be used to distinguish acute cellular rejection from recurrent hepatitis C infection in liver allografts

Cirrhosis secondary to chronic hepatitis C virus (HCV) is the most common indication for liver transplantation. Recurrence of HCV infection in the liver allograft occurs at a high rate. The differentiation of recurrent HCV infection from acute cellular rejection (ACR) represents a difficult challenge in transplantation pathology. The c-Kit receptor is a tyrosine kinase membrane protein encoded by the c-Kit proto-oncogene, which is expressed on mast cells and on hematopoietic stem and progenitor cells. Mast cells are important effector cells of a broad range of immune responses. Recently, c-Kit+ mast cells were shown to form part of the inflammatory infiltrate in acute liver allograft rejection. A strong relationship was found between c-Kit+ cell densities and increasingly severe rejection. The present study sought to determine whether the presence of c-Kit+ cells could be used to distinguish between ACR and recurrent HCV in liver allografts. Immunohistochemical staining for c-Kit was performed on 20 transplant biopsy specimens from 10 patients with mild to moderate ACR and 10 other patients with recurrent hepatitis C. The number of c-Kit+ cells per portal tract varied with the density of the overall inflammatory infiltrate. There was no significant difference between the number of c-Kit+ cells in the biopsy specimens that carried a diagnosis of ACR and those from patients who had been diagnosed as having recurrent HCV. It was concluded that immunohistochemical staining for the presence of c-Kit+ mast cells cannot be used to differentiate between ACR and recurrent HCV infection in liver allograft biopsy specimens.

General aspects and pitfalls in liver transplant pathology

Pathology in a liver transplant setting addresses four different topics: establishment of a definite diagnosis of the liver disease before listing for transplantation, evaluation of the donor liver with regard to pre-existing diseases, in particular macrovesicular steatosis and fibrosis, assessment of the hepatectomy specimen, and post-transplant biopsy evaluation. Of these, post-transplant biopsy evaluation is the most challenging and clinically the most relevant issue. It requires fast diagnoses to facilitate specific treatment and it has to incorporate a broad spectrum of differential diagnoses. Precise knowledge about rejection, post-transplant therapy, pathology of immunosuppression, and recurrence of the initially underlying liver disease including the characteristic time peaks and atypical histological presentations (e.g., fibrosing cholestatic hepatitis) is needed to evaluate specific and combined histological pictures of liver damage. For adequate interpretation of post-transplant biopsies the hepatopathologist has to be informed about the essential clinico-anamnestic aspects such as time course, medication, imaging results, and serology.

Detection of HCV antigens in liver graft: relevance to the management of recurrent post-liver transplant hepatitis C

The aim of this study was to evaluate how the immunohistochemical detection of liver hepatitis C virus (HCV) antigens (HCV-Ag) could support the histologic diagnosis and influence the clinical management of post-liver transplantation (LT) liver disease. A total of 215 liver specimens from 152 HCV-positive patients with post-LT liver disease were studied. Histologic coding was: hepatitis (126), rejection (34), undefined (24; coexisting rejection grade I and hepatitis), or other (31). The percentage of HCV-Ag infected hepatocytes were evaluated, on frozen sections, by an immunoperoxidase technique. HCV-Ag were detectable early in 57% of cases within 30 days post-LT, 92% of cases between 31 and 180 days, and 74% of cases after more than 180 days. Overall, HCV-Ag were detected more frequently in histologic hepatitis as compared to rejection (P < 0.0001) with a higher percentage of positive hepatocytes (P < 0.00001). In 16 patients with a high number of HCV-Ag-positive hepatocytes (65%; range 40-90%) a clinical diagnosis of recurrent hepatitis (RHC) was made despite inconclusive histopathologic diagnosis. Multivariate analysis identified the percentage of HCV-Ag-positive hepatocytes and the time post-LT as independent predictors for RHC (P = 0.008 and P = 0.041, respectively) and the number of HCV-Ag-positive hepatocytes >/=50% as the only independent predictor for nonresponse (P < 0.001) in 26 patients treated with alpha-interferon plus ribavirin. In conclusion, HCV reinfection occurs early post-LT, reaching its peak within 6 months. Immunohistochemical detection of post-LT HCV reinfection support the diagnosis of hepatitis when the histologic features are not conclusive. A high number of infected cells, independently from the genotype, represents a negative predictive factor of response to antiviral treatment.

Liver biopsy interpretation for causes of late liver allograft dysfunction

Evaluation of needle biopsies and extensive clinicopathological correlation play an important role in the determination of liver allograft dysfunction occurring more than 1 year after transplantation. Interpretation of these biopsies can be quite difficult because of the high incidence of recurrent diseases that show histopathological, clinical, and serological features that overlap with each other and with rejection. Also, more than one insult can contribute to allograft injury. In an attempt to enable centers to compare and pool results, improve therapy, and better understand pathophysiological disease mechanisms, the Banff Working Group on Liver Allograft Pathology herein proposes a set of consensus criteria for the most common and problematic causes of late liver allograft dysfunction, including late-onset acute and chronic rejection, recurrent and new-onset viral and autoimmune hepatitis, biliary strictures, and recurrent primary biliary cirrhosis and primary sclerosing cholangitis. A discussion of differential diagnosis is also presented.

Endotheliitis in chronic viral hepatitis: a comparison with acute cellular rejection and non-alcoholic steatohepatitis

Endotheliitis is an important histologic feature of acute cellular rejection (ACR) in the liver allograft. This change is not specific, however, and has been suggested to be associated with various liver diseases. End-stage liver disease owing to chronic hepatitis C is the leading indication for transplantation in North America, and its recurrence in allograft recipients is common. Because the presence of endotheliitis remains a diagnostic and therapeutic dilemma in transplant pathology, we investigated the prevalence and severity of endotheliitis in chronic liver diseases including hepatitis C. Endotheliitis was evaluated in 128 nontransplant liver biopsies of chronic liver diseases before therapy, including hepatitis C (HCV, n=62), hepatitis B (HBV, n=17), and nonalcoholic steatohepatitis (NASH, n=49). Eighty posttransplant biopsies with ACR were also reviewed. Subendothelial and supraendothelial endotheliitis were separately scored in the portal and central regions using a semiquantitative scoring system from 0 to 4. Pathologists were blinded to the clinical histories, and each biopsy was independently scored by 2 pathologists. Histologic activity index was also scored subsequently for cases of chronic HCV and HBV, using the modified Knodell (Ishak) score. Mean endotheliitis scores>1 were seen in 60%, 35%, and 6% of HCV, HBV, and NASH patients, respectively. The scores for portal subendotheliitis and supraendotheliitis were significantly higher in the viral hepatitis group than in the NASH group (P<0.01). There was no significant difference in the scores of endotheliitis comparing HCV to HBV. ACR group showed significantly higher scores in both portal and central subendotheliitis than any other group (P<0.00005). In the HBV and HCV groups with mean scores of portal subendotheliitis>1 (n=44), mean Ishak scores for portal inflammation and periportal injury were 2.43 and 2.34, respectively; whereas in those with less severe portal subendotheliitis (<or=1, n=35), Ishak scores were 1.66 and 1.37, respectively (P=0.00001 for portal inflammation and P=0.00001 for periportal injury, respectively). Our results suggest that minimal to mild subendotheliitis is common in portal veins in chronic hepatitis C and B, but is significantly less intense than that seen in ACR. The degree of endotheliitis correlates with inflammatory activity. These observations may help minimize the risk of overdiagnosing ACR when the patient has recurrent viral hepatitis, and may help clinicians avoid exposing patients to unnecessary immunosuppressive regimens when patients do not have cellular rejection.

Natural history of patients with recurrent chronic hepatitis C virus and occult hepatitis B co-infection after liver transplantation

It is uncertain whether occult hepatitis B virus co-infection will hasten progressive liver disease in chronic hepatitis C patients after liver transplantation. This study evaluated fibrosis progression and severe fibrosis in 118 consecutive hepatitis B surface antigen-negative patients with virological and histological evidence of recurrent chronic hepatitis C infection co-infected with occult hepatitis B virus after liver transplantation. HBV DNA was detected from serum at the time of recurrent chronic hepatitis C infection by polymerase chain reaction. Each subject underwent a repeat liver biopsy 5 years post-liver transplantation. Occult hepatitis B virus co-infection was present in 41 of the 118 (34.7%) patients. At 5 years post-liver transplantation, 13 of the 41 occult hepatitis B virus co-infected patients compared with 16 of the 77 patients without occult hepatitis B virus co-infection developed fibrosis progression (31.7% vs. 20.8%, respectively, p = 0.39). Eight of 41 the occult hepatitis B virus co-infected patients compared with 13 of the 77 patients without occult hepatitis B virus co-infection had severe fibrosis (19.5% vs. 16.9%, respectively, p = 0.97). In conclusion, occult hepatitis B virus co-infection in patients with recurrent chronic hepatitis C infection was not associated with accelerated fibrosis progression or severe fibrosis after liver transplantation.

Post-transplant reactivation of hepatitis C virus: lymphocyte infiltration and the expression of adhesion molecules and their ligands in liver allografts

Hepatitis C virus (HCV) recurrence after liver transplantation has been associated with chronic rejection. Biopsies from 10 patients with post-transplant HCV were examined for expression of adhesion molecules ICAM-1, VCAM-1, and ELAM-1, number of lymphocytes positive for their ligands LFA-1, VLA-4, and SLeX, and activation markers MHC class II antigens and IL2-R by immunohistochemistry. The phenotypes of the graft-infiltrating lymphocytes were determined. Results were compared to those for patients with normal graft function or rejection. Five recipients with HCV reactivation and one with de novo HCV had a biopsy available showing induction of ICAM-1 in sinusoidal endothelium (p<0.05) and hepatocytes (p<0.01), and Class II antigens in hepatocytes (p<0.01), compared to normal controls. Lymphocytes in the graft infiltrate expressed LFA-1, VLA-4, and Class II antigens, but IL2-R was not significantly expressed. CD3+, CD4+, and CD8+ cells were observed. In our study, HCV recurrence was not associated with acute or chronic rejection, and the inflammation was due to the viral infection.

Morphologic Features of Hepatitis C Recurrence in Patients After Orthotopic Liver Transplantation-Preliminary Analysis of our Case Observations

INTRODUCTION

Hepatitis C virus (HCV) recurrence is almost universal in patients after liver transplantation. The diagnosis of reinfection is more difficult than that of a primary process, as shown by our pathomorphologic analysis of cases of HCV recurrence.

MATERIAL

During 5.5 years, 240 liver biopsies included 54 obtained from liver transplant recipients with primary HCV infections, among whom 26 (56.5%) had clinical signs and symptoms of hepatitis. Nineteen patients from this population underwent 30 liver biopsies. In addition, seven biopsies were performed in five patients without clinical signs of reinfection.

RESULTS

In 44.2% of patients with HCV recurrence and 15% without reinfection, the intensity of the primary process in the native livers was assessed as high. Reinfection was found in all patients with liver carcinoma and 67% with hepatocyte dysplasia. Histologic signs of infection were estimated as minimal (n = 4), mild (n = 19), or moderate (n = 4). In five patients with reinfections and one without recurrence, histologic manifestations of acute rejection were also observed. In conclusion, HCV was the indication for liver transplantation in 22.4% cases. Clinical manifestation of recurrence was found in 56.5% of the patients, who tended to be older than those without disease recurrence. Upon microscopy, lobular lesions predominated over the portal changes. Factors predisposing to HCV recurrence were coexistence of other liver disorders, a high intensity of the inflammatory process, hepatocyte dysplasia, and/or hepatocellular carcinoma in the native liver and acute rejection episodes.

Management of hepatitis C virus infection in the setting of liver transplantation

1. Posttransplantation recurrence of hepatitis C virus infection is a universal phenomenon with a highly variable natural history. 2. Approximately 10% to 25% of hepatitis C virus- infected recipients of liver allografts will develop cirrhosis within 5 years' after transplantation. 3. The 1-year actuarial risk of hepatic decompensation after recurrence of cirrhosis approximates 42%. 4. Some of the factors associated with aggressive recurrence include donor and recipient age, recent year of transplantation, recipient gender and race, the use of antithymocyte globulin, and high dose of corticosteroids. 5. Highly aggressive recurrent hepatitis C virus infection leading to cirrhosis fares poorly after retransplantation in the presence of hyperbilirubinemia and renal failure, with a 1-year survival of approximately 40%. 6. Elevated serum aminotransferases are a poor indicator or recurrent disease. 7. Current sustained virological response after combination pegylated alpha interferon and ribavirin treatment is approximately 25%. 8. There is no consensus on initiation time point, duration of treatment, or dosage. Given immunosuppression, at least 48 weeks of therapy is a reasonable approach. 9. Treatment for 48 weeks is cost effective. Incremental cost-effectiveness ratio for men aged 55 years is $29,100 per life-year saved.

Effects of the hepatitis C virus core protein on innate cellular defense pathways

The hepatitis C virus (HCV) core protein is thought to contribute to HCV pathogenesis through its interaction with various signal transduction pathways. In this study, we explored the interaction of the core protein with innate defense pathways (interferon [IFN] regulatory factor [IRF], Jak-Stat, and inducible nitric oxide synthase [iNOS]) in HeLa and Huh7 human cell lines. Expression of a patient-derived genotype 1b core protein activated human IRF-1 and guanylate-binding protein-2 (GBP-2) promoters, induced IRF-1 mRNA, but failed to induce IRF-3 phosphorylation. HCV core protein caused dose-dependent induction of the IFN-beta promoter and IFN-beta mRNA but not the IFN-alpha1 and IFN-alpha4 promoters. In the presence of IFN-alpha, core expression was associated with increased IFN-stimulated gene factor 3 (ISGF3) binding to the IFN-stimulated response element (ISRE) and tyrosine phosphorylation of Stat1. Core expression resulted in dose-dependent activation of the ISRE and gamma activated sequence (GAS) promoters, in both the absence and the presence of either IFN-alpha or IFN-gamma. Core stimulated the human iNOS promoter and induced iNOS protein. The data indicate that HCV core can modulate IRF, Jak-Stat, and iNOS pathways and suggest mechanisms by which core could affect HCV persistence and pathogenesis.

Reliability of histopathologic assessment for the differentiation of recurrent hepatitis C from acute rejection after liver transplantation

Histopathologic assessment is considered essential for the differentiation of recurrent hepatitis C (RHC) from acute cellular rejection (ACR) after liver transplantation (LT); however, there is limited information regarding its reliability. The aim of this study was to determine the interobserver and intraobserver agreement of the histopathologic diagnosis of RHC vs. ACR, and to determine the reliability of specific histopathologic features for the differentiation of RHC from ACR. Liver biopsy specimens from 105 consecutive patients transplanted for hepatitis C virus (HCV)-related liver disease were studied retrospectively. All the biopsies were performed for evaluation of abnormal liver enzymes within the 1st year after LT. The slides were blindly coded and assessed by 5 liver-transplant pathologists, practicing at 3 medical centers. The pathologists were asked to render a diagnosis, and determine the severity of the disease. Four of the pathologists were asked to determine the presence and severity of 36 histopathologic features. A total of 34 of the samples were then blindly resubmitted to each of the 4 pathologists to determine the intraobserver agreement. There was a slight agreement (kappa = .12) among the 5 pathologists on the histopathologic diagnosis. All 5 pathologists were in agreement on the diagnosis of RHC in only 5 patients (5%) and on the diagnosis of ACR in only 2 patients (2%). The best agreement among any 4 pathologists was fair (kappa = .20). Slight to moderate agreement occurred on the main histological features considered to be important in the diagnosis of ACR. Intraobserver agreement ranged from slight (kappa = .19) to moderate (kappa = .42) among 4 pathologists. In conclusion, the histopathologic differentiation of RHC from ACR after LT had relatively low interobserver and intraobserver agreement rates, and hence showed low reliability. Histopathologic assessment should be used cautiously for the differentiation of RHC from ACR post-LT.

Hepatitis C etiology of liver disease is strongly associated with early acute rejection following liver transplantation

Although recurrent hepatitis C (HCV) occurs universally after liver transplantation (LT), its tempo and severity are variable and unpredictable. Diagnosis and treatment of early acute rejection (EAR) likely affect the course of recurrent HCV disease. We have studied a contemporary cohort of LT recipients to reexamine risk factors for EAR. We hypothesized that HCV etiology may represent a significant risk factor for EAR for many reasons. First, recurrent disease commonly causes biochemical abnormalities prompting allograft biopsy. Second, overlapping histologic features of acute rejection and recurrent HCV ambiguity may result in diagnostic ambiguity. Finally, the biology of hepatitis may precipitate an antidonor response in addition to an antiviral response. Records of 285 adult recipients undergoing primary LT for cirrhosis between January 1, 1999, and December 31, 2002, were retrospectively reviewed. EAR was defined as a biopsy-proven or an empirically treated episode within 6 months of LT. Cox proportional hazards analysis identified donor, recipient, transplant, and posttransplant characteristics associated with EAR; Kaplan-Meier analysis was used to assess rejection by etiology. HCV cirrhosis was the etiology for 51% of all LT recipients. There were 135 episodes of EAR (127 biopsy proven) in 117 recipients for an overall incidence of 41%. Patient groups with HCV and cholestatic / autoimmune disease groups exhibited the highest incidence of rejection at 49%. Recipient gender, ethnicity, etiology, LT year, and posttransplant immunosuppression levels were risk factors for EAR in univariate analysis; HCV etiology and female gender remained robust risk factors in multivariate analysis. Interferon-based therapy did not impact the incidence or timing of EAR. In conclusion, HCV etiology is strongly associated with EAR. HCV allograft reinfection may create an immunologic environment predisposed to EAR. Alternatively, the association of HCV and EAR may result from an increased frequency of allograft biopsy and may be further exacerbated by inability to accurately diagnose EAR in the setting of recurrent HCV.

The natural history and outcome of liver transplantation in hepatitis C virus-infected recipients

1. Recurrence of hepatitis C infection is universal and immediate after liver transplantation. 2. Graft and patient survival is reduced in liver transplantation recipients with recurrent hepatitis C virus infection compared with hepatitis C virus-negative recipients. 3. The natural history of chronic hepatitis C is accelerated after liver transplantation compared with nontransplantation chronic hepatitis C; 20% to 40% of patients progress to allograft cirrhosis within 5 years, compared with less than 5% of nontransplantation patients. 4. The rate of fibrosis progression is not uniform and may change over time. 5. The rate of progression from cirrhosis to decompensation is accelerated after liver transplantation. The rate of decompensation is >40% at 1 year and >60% at 3 years, compared with <5% and <10%, respectively, in immunocompetent patients. 6. The rate of progression from decompensation to death is also accelerated after liver transplantation. The 3-year survival is <10% after the onset of hepatitis C virus-related allograft failure, compared with 60% after decompensation in immunocompetent patients.

Outcome of liver transplantation for patients infected by hepatitis C, including those infected by genotype 4

Predictors of hepatitis C virus (HCV)-related liver disease posttransplantation are still unclear. The impact of HCV genotype on outcome of transplantation has been studied, but conclusions are not in agreement. The role of HCV genotype 4 on the result of liver transplantation requires further study. The aim of this study is to examine the outcome of liver transplantation for patients with HCV genotype-4 infection. The study group included 128 patients who underwent transplantation for HCV infection: 28 patients, genotype 1; 11 patients, genotype 2; 19 patients, genotype 3; and 32 patients, genotype 4. For 64 of 128 patients, genotype was known and an assessable histological specimen was available. Median interval from transplantation to biopsy was 1.92 years (range, 0.24 to 11.48 years). Twenty-six percent of HCV genotype-4 patients developed either severe fibrosis or cirrhosis versus 6.7% in the genotype non-4 group (P =.04). A statistically significant greater fibrosis progression rate was observed in genotype-4 than genotype non-4 patients. In univariate and multivariate analysis, rapid liver fibrosis was associated with the presence of HCV genotype-4 infection. In addition, donor and recipient age and graft warm ischemic time also were associated with rate of fibrosis progression. Five-year cumulative rates for the development of cirrhosis or severe liver fibrosis were 84% in genotype-4 and 24% in genotype non-4 patients (P =.02). Five-year survival rates for patients with genotypes 1, 2/3, and 4 were 72%, 80%, and 79%, respectively (P =.8). In conclusion, 5-year survival for patients who underwent transplantation for HCV genotype-4 infection was similar to that of genotype non-4 patients; however, more severe fibrosis and rapid fibrosis progression was observed after transplantation in patients with genotype-4 infection.

Applications and limitations of blood eosinophilia for the diagnosis of acute cellular rejection in liver transplantation

This study evaluates the predictive value of the blood eosinophil count in the diagnosis of acute cellular rejection, its value as a marker of response to treatment, the diagnostic use in a subgroup of patients with normal transaminases and compares blood eosinophilia in patients with and without hepatitis C virus infection. A consecutive cohort of 101 liver transplant patients, 275 liver biopsies, and blood eosinophils recorded on the day or one day before biopsy were analyzed. An elevated eosinophil count has a positive predictive value for acute cellular rejection of 82%. A normal eosinophil count excludes moderate/severe rejection with a predictive value of 86%. The eosinophil count decreases in 69% of patients following treatment of acute cellular rejection with corticosteroids irrespective of treatment outcome. Acute cellular rejection in the presence of an elevated eosinophil count occurs significantly less often (p = 0.007) in patients with hepatitis C virus. An elevated eosinophil count is a valuable marker of acute cellular rejection. However, blood eosinophil levels should not be used to predict acute cellular rejection following treatment with corticosteroids. Blood eosinophilia, seen less often in patients with hepatitis C virus, may reflect an over-diagnosis of acute cellular rejection in these patients.

Discordance between ALT values and fibrosis in liver transplant recipients treated with ribavirin for recurrent hepatitis C

Hepatitis C virus (HCV) recurrence is a serious problem after orthotopic liver transplantation (OLT). The role of ribavirin as a single agent to treat recurrent HCV is controversial. Our aim was to evaluate the correlation between alanine aminotransferase (ALT) levels and histological findings in OLT recipients treated with ribavirin monotherapy for recurrent HCV. The mean [+/- standard error (SE)] age of 11 patients was 50.1 (SE +/- 8.6) years. The estimated mean dose and duration of ribavirin treatment (+/- SE) was 661.5 (+/- 52.5) mg and 20.4 (+/- 1.7) months, respectively. Five patients required either dose reduction or erythropoietin. We found a significant decrease of mean (+/- SE) ALT value from 246 +/- 44.8 U/L to 109.4 +/- 49.1 U/L (p = 0.002) in patients treated with ribavirin. However, there was also significant worsening of interface activity (p = 0.03) and fibrosis (p = 0.02). No significant association was found between ALT values and (i) stage of hepatic fibrosis, (ii) interface activity, (iii) lobular activity and (iv) HCV RNA values. Our results suggest that HCV disease can progress despite a significant decrease in ALT values. ALT values are inadequate markers of the ribavirin monotherapy and can lead to erroneous conclusions of efficacy.

Hepatitis C virus--cell interactions and their role in pathogenesis

In summary, HCV-cell interactions include those directly involved with the HCV life cycle such as virus attachment, entry, and replication. Included within this broad area of research are the interactions of HCV proteins with the IFN system, cytokine and chemokine pathways such as IL-8, and various other cellular proteins and pathways. The plethora of contradictory and sometimes confusing accessory HCV-host interactions defies precise predictions of their role in HCV biology. It is clear that these virus-cell interactions affect HCV replication, antiviral resistance, persistence, and pathogenesis. Because HCV-host interactions are initiated immediately on infection, they are operative during acute HCV infection, whereby HCV interacts with innate cellular antiviral and immune systems. The magnitude and duration of these HCV-host interactions therefore may influence the development of acquired immunity. Because HCV exists as a quasispecies in all infected individuals, heterogeneity in biological responses to HCV-host interactions is predicted, revealing opportunities for the development of various genotypic and phenotypic prognostic indicators. With the model systems in place, these hypotheses can be tested. The challenge for the future is to determine if there is a hierarchical importance to these interactions, to delineate how these virus-cell interactions affect the patient infected with HCV, and to determine whether any of these interactions represents a target for therapeutic intervention.

Use of fluoroquinolones in patients with chronic hepatitis C virus-induced liver failure

Fluroquinolone antibiotics have been reported to have antiviral properties against RNA viruses, including hepatitis C virus (HCV). In the present study, five patients with advanced liver disease secondary to chronic HCV received 500 mg daily of oral ciprofloxacin for 30 days. Serum HCV-RNA levels and liver enzyme abnormalities remained largely unchanged. Thus, the role of fluoroquinolones as antiviral agents for chronic HCV in patients with advanced liver disease appears to be limited.

Hepatitis C virus-host interactions: the NS5A protein and the interferon/chemokine systems

The interactions that occur between viral proteins and host factors, such as cellular proteins and signal transduction machinery, have a significant influence on the replication, persistence, and pathogenesis of all viruses. This is exemplified by hepatitis C virus (HCV), which infects an estimated 3% of the world's population and is a significant cause of liver disease. HCV-host interactions also affect the outcome of interferon (IFN) antiviral therapy, which is effective only in certain patients. In this review, we focus on the HCV nonstructural 5A (NS5A) protein, a model for diverse virus-host interactions, and highlight the interaction of viruses, including HCV, with the chemokine system.

Utilization of acidophil bodies in the diagnosis of recurrent hepatitis C infection after orthotopic liver transplantation

BACKGROUND

The distinction between acute rejection and early recurrent hepatitis C infection (RHCV) in the setting of orthotopic liver transplantation is often difficult. In liver biopsies acidophil bodies and lobular hepatitis are used to suggest a diagnosis of RHCV over rejection, however, the reliability of this practice has not been established. Because portal tract changes in RHCV and rejection often overlap, we sought to determine whether the degree of hepatocyte acidophil body formation seen on liver biopsies could be used to distinguish between these two conditions.

METHODS

Quantification of acidophil bodies was performed on liver biopsies in orthotopic liver transplant patients with RHCV (n = 10), non-hepatitis C orthotopic liver transplant patients with uncomplicated rejection episodes (n = 10) and non-transplant patients with chronic hepatitis C infection (n = 10). Hematoxylin and Eosin stained slides from all three groups were randomized and tissue segments 1.0 cm in length and of variable width (0.04-0.13 cm) were examined at 200x magnification in a blinded fashion by two pathologists in order to quantify the number of acidophil bodies/cm(2). Lobular chronic inflammation was also graded on a 0-3+ scale.

RESULTS

Liver biopsies taken at the onset of RHCV exhibited 606 +/- 101 acidophil bodies/cm(2) (mean +/- standard error of mean, range 200-1390). These counts were significantly greater (P =.0061, paired 2-tailed t-test) than the 241 +/- 53 acidophil bodies/cm(2) (range 80-514) for acute rejection, and the 194 +/- 21 acidophil bodies/cm(2) (range 100-333) for non-liver transplant chronic hepatitis C infection (P =.0013). No difference in lobular inflammation between index RHCV and rejection biopsies was detected.

CONCLUSIONS

Although there is overlap, on average there are twice as many acidophil bodies in the initial stage of RHCV when compared with acute rejection (average of 55 per linear cm in RHCV versus 21 per linear cm for rejection). Lobular inflammation was not a reliable indicator of the initial onset of RHCV.

Is it cost-effective to treat recurrent hepatitis C infection in orthotopic liver transplantation patients?

Hepatitis C virus (HCV) recurs in the allograft almost universally after orthotopic liver transplantation (OLT), with a variable course ranging from mild hepatitis to frank cirrhosis. The uncertain prognosis after OLT has lead to widely increased use of antiviral therapy in the post-OLT setting. We compared two scenarios (antiviral therapy versus no antiviral therapy) using a Markov-based decision analytic model to simulate costs and health outcomes for recurrent HCV in three age and sex cohorts of post-OLT patients. Efficacy outcomes included total costs, cases of cirrhosis prevented, cases of death prevented, life-years gained, and cost per life-year saved. One-way sensitivity analyses were performed for sustained viral response; annual drug cost, discount rate, compliance, cirrhosis rate, decompensation rate, and cost of dying. Two-way sensitivity analyses were performed to compare effects of (1) changing sustained viral response and antiviral therapy costs, and (2) changing the sustained viral response and cirrhosis rate. The incremental cost-effectiveness ratio for the reference patient cohort of 1,000 men aged 55 years was $29,100 per life-year saved. The model was sensitive to drug costs, cirrhosis rate, and sustained viral response. The two-way sensitivity analysis showed that antiviral therapy remained cost-effective even if drug costs increased, as long as these increases were associated with higher sustained viral responses. The cost-effectiveness ratio also was sensitive to age and sex of cohort. The decision to treat HCV after OLT with antiviral therapy usually is based on many considerations. Such treatment can be cost-effective if baseline assumptions are met. Our model was sensitive to antiviral drug costs, cirrhosis rate, and sustained viral response. Patients with a progressive course of recurrent HCV are likely to have the greatest gain from antiviral therapy.