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J M Vierling

Publications and source records attributed to J M Vierling.

At least 19 recordsLinked to original sources
PubMed2004

Sirolimus-induced hyperlipidaemia in liver transplant recipients is not dose-dependent.

BACKGROUND: Sirolimus is a potent immunosuppressive medication that acts by inhibiting T-cell proliferation. It has been used in kidney transplantation because of its lack of nephrotoxicity. It is now being investigated in liver transplantation, but there are concerns about safety and long-term side effects such as dyslipidaemia. Hypertriglyceridaemia is a common adverse event seen with sirolimus use, and often does not respond to dose reduction or anti-lipemic drugs. METHOD: We report six patients who have developed significant hyperlipidaemia while receiving sirolimus, in spite of therapeutic trough levels. CONCLUSION: All six patients showed either resolution or improvement in lipid levels with discontinuation of sirolimus.

Adult↗
PubMed2001

Viral, host and interferon-related factors modulating the effect of interferon therapy for hepatitis C virus infection.

The estimated prevalence of hepatitis C virus infection in the US is approximately 1.8%. Although interferon monotherapy and combination therapy of interferon with ribavirin represent mainstay for treating HCV infection, the rate of sustained virologic response remains suboptimal. The growing evidence suggested that the clinical sequence and treatment response of chronic hepatitis C are determined by a dynamic, complex tripartite relationship among HCV infection, the host immune response, and the effect of different interferon regimens. The treatment response is associated with various viral factors including the pretreatment viral level, dynamic change of viral level during treatment, viral genotype quasispecies and nucleotide mutation in nonstructural protein 5A of hepatitis C virus. Host factors that may affect treatment response include age, gender, race, HLA alleles and the host immune responses. Interferon regimens, including type, dose, frequency and duration of treatment and combination of interferon with other anti-HCV agents also alter the therapeutic response. Understanding these complicated interaction may provide better insights into the mechanism(s) of interferon response, leading to more effective clinical application of interferon therapy.

Antiviral Agents↗
PubMed2001

Animal models for primary sclerosing cholangitis.

Since the aetiopathogenesis of primary sclerosing cholangitis (PSC) in humans remains undefined, investigators have studied a variety of animal models to gain insights into immunopathogenetic mechanisms associated with obliterative fibrous cholangitis of intra- and extra-hepatic bile ducts. To date, no animal model has been developed that exhibits all of the attributes of PSC. Rodent models instigated by bacterial cell components or colitis are promising because they may help to explain the strong association between PSC and inflammatory bowel disease (IBD). Other models of direct injury to biliary epithelia, peribiliary vascular endothelia or portal venous endothelia indicate that inflammation, chemokines and cytokines can produce diffuse sclerosis of bile ducts. Models of toxic, infectious or intra-luminal injury of the biliary tract also exhibit focal biliary sclerosis mediated by inflammation and cytokines. The histopathology of several models suggests a sequence of events beginning with secretion of proinflammatory cytokines by activated hepatic macrophages followed by peribiliary infiltration with CD4 and CD8 T cells with a T helper 1 phenotype. These results strongly suggest co-ordinated, pathogenetic roles for both the innate and adaptive immune responses. However, the stimuli that initiate and perpetuate peribiliary fibrosis remain unknown. Interestingly, several models are also associated with the development of anti-neutrophil cytoplasmic antibodies that react in a perinuclear and cytoplasmic pattern similar to that observed in patients with ulcerative colitis and/or PSC. Finally, models of extra-hepatic biliary obstruction continue to provide important information about the pathogenesis of portal fibrosis and secondary biliary cirrhosis that occurs in PSC and other diseases with obstruction of bile flow. Future studies in either existing or new animal models should advance our understanding of the pathogenesis of PSC, the major prerequisite for the development of effective therapies.

Animals↗
PubMed2001

Transmission of hepatitis B infection from hepatitis B core antibody--positive liver allografts is prevented by lamivudine therapy.

Donor shortage has led to the use of hepatitis B core antibody (anti-HBc)--positive (anti-HBc(+)) liver allografts for patients in need of relatively urgent orthotopic liver transplantation (OLT). Because anti-HBc(+) allografts transmit hepatitis B virus (HBV) infection at a high rate, effective prophylaxis is required. We assessed the effectiveness of lamivudine in preventing HBV transmission by anti-HBc(+) allografts. Between March 1996 and March 2000 at Cedars-Sinai Medical Center (Los Angeles, CA), 15 of 169 patients (8.9%) received liver allografts from anti-HBc(+) donors. Six patients were hepatitis B surface antigen (HBsAg)(+) (group 1), and 9 patients were HBsAg negative (HBsAg(-); group 2) before OLT. All patients were administered lamivudine, 100 or 150 mg/d, orally after OLT. Patients who were HBsAg(+) before OLT also were administered hepatitis B immunoglobulin (HBIG) prophylaxis. Hepatitis B serological tests were performed on all patients, and HBV DNA was determined in liver tissues in 10 patients. All 15 patients remained HBsAg(-) at their last follow-up 2 to 40 months (mean, 17 months) post-OLT. All patients in group 1 had antibody to HBsAg (anti-HBs) titers greater than 250 mIU/mL post-OLT (mean follow-up, 20 months; range, 7 to 40 months). Of the 2 patients in group 1 who underwent liver biopsy after OLT, 1 patient had detectable hepatic HBV DNA despite being anti-HBs(+) and HBsAg(-). Among the patients in group 2, none acquired anti-HBc or HBsAg. Hepatic HBV DNA was undetectable in the 7 patients in group 2 who underwent liver biopsy after OLT. Anti-HBc(+) allografts can be safely used in patients who undergo OLT for chronic hepatitis B and susceptible transplant recipients if prophylaxis with combination HBIG and lamivudine or lamividine alone is administered after OLT, respectively. However, more data are needed to determine the efficacy of lamivudine monotherapy in preventing transmission of HBV infection from anti-HBc(+) liver allografts to susceptible recipients.

Adult↗
PubMed2000

Overview of hepatitis B and transplantation in the hepatitis B patient.

Hepatitis B is a disease that infects 300,000 people in the United States each year, resulting in 15,000-30,000 cases of chronic hepatitis. Outcomes include death; development of chronic carrier state, chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Hepatitis B surface antigen (HBsAg) carriers, especially those with cirrhosis, are at high risk for development of hepatocellular carcinoma. Histologically, chronic carriers of HBsAg may have a range of degree of tissue changes, ranging from normal, to varying degrees of portal or lobular inflammation, to significant cell injury with widespread necrosis, fibrosis and cirrhosis. Current histological grading systems reflect both graded inflammation and stage of fibrosis.

Carcinoma, Hepatocellular↗
PubMed2000

Posttransplantation: future therapies.

Recent advances in prophylaxis and treatment of hepatitis B virus (HBV) infection after liver transplantation have improved the outcome of liver transplantation for hepatitis B. Currently, the long-term use of hepatitis B immune globulin (HBIG) and/or nucleoside analogues are the only effective therapies to prevent or ameliorate HBV recurrence in liver transplant patients. However, they are very expensive, and breakthrough infections due to resistant HBV mutants are not infrequent. New strategies are being sought to decrease the risks of breakthrough infection and to increase the cost-effectiveness of liver transplantation for hepatitis B. Vaccination to prevent de novo infection is strongly recommended before transplantation, despite a decreased response in this immunosuppressed population. Adoptive transfer of immunity with such therapies as bone marrow or cytotoxic T lymphocyte transplants or xenotransplantation of an organ from a donor, which is not susceptible to infection by HBV may be effective in preventing or treating recurrent HBV posttransplantation. In addition, gene therapies and use of nucleoside and nucleotide analogues to disrupt various stages of the HBV life cycle may prevent or slow viral replication or assembly of the virus. Ultimately, the most effective therapy for the prevention of recurrent hepatitis B after liver transplantation will involve a combination of HBIG with one or more of the new antiviral agents.

Antiviral Agents↗
PubMed2000

Case studies of the hepatitis B patient: a panel discussion.

In recent years, there have been significant advances in the treatment of patients with hepatitis B who are candidates for liver transplantation. This includes the prevention and management of hepatitis B posttransplantation. However, there is no established protocol for treating these patients. Ultimately, the goal would be to have patients HBV-DNA negative pretransplantation and then to prevent HBV recurrence posttransplantation to help ensure their quality of life. Several clinical case scenarios are presented and possible treatment solutions have been suggested. The timing of a transplant is critical due to the risk of viral mutation while the patient is on a nucleoside analogue antiviral agent and waiting for an organ. One successful option might be to start therapy pretransplant and continue it posttransplant. Combination therapy appears to provide the most effective course of treatment. This should include a nucleoside analogue and patients should be covered with hepatitis B immune globulin throughout the course of therapy. Several other variations of combination therapy are discussed, but many clinical issues remain to be resolved. Guidelines for future studies designed to answer these questions are proposed.

Adult↗
PubMed1999

Immortalized intrahepatic mouse biliary epithelial cells: immunologic characterization and immunogenicity.

Nonsuppurative destructive cholangitis (NSDC), a process of T-cell-mediated destruction of biliary epithelia observed in primary biliary cirrhosis (PBC), graft-versus-host disease (GVHD), and hepatic allograft rejection (HAR), also occurs in the B10. D2-->BALB/c model of GVHD. To advance studies of immunopathogenesis in this murine model, we immortalized 4 BALB/c intrahepatic biliary epithelial cell (BEC) lines as a reliable source of target cells. Freshly isolated BEC, as well as each cell line, expressed cytokeratin-19 (CK-19), epithelial cell adhesion molecule (EPCAM) and cystic fibrosis transmembrane conductance regulator (CFTR). None expressed albumin. Immortalized cells also expressed SV40 large T antigen. Class I major histocompatibility complex (MHC) was expressed by >97% of immortalized cells, while class II MHC and intercellular adhesion molecule-1 (ICAM-1) expression ranged from 0% to 13% and 14% to 74%, respectively. Interferon gamma (IFN-gamma) induced aberrant class II MHC expression and increased expression of ICAM-1. Variable proportions of immortalized cells expressed B7-1/B7-2 molecules and FAS. IFN-gamma significantly reduced B7-1 expression in some lines and significantly increased B7-2 expression in others. Allografts of freshly isolated and immortalized BEC injected into subscapular fat pads spontaneously formed duct-like structures. Inflammation was absent in BALB/c recipients. In contrast, inflammatory lesions in B10.D2 recipients were reminiscent of NSDC. Our results indicate that BALB/c-immortalized intrahepatic biliary cells: 1) retain the phenotype of mouse BEC; 2) can be induced to express aberrant class II MHC and increased ICAM-1; 3) express costimulatory B7-1/B7-2 molecules and FAS; and 4) spontaneously form duct-like structures after in vivo injection that are immunogenic in B10.D2 mice. These cell lines should facilitate future studies of the immunopathogenesis of NSDC in the B10. D2-->BALB/c murine model.

Animals↗
PubMed1999

Autoimmune cholangiopathy.

Currently available evidence is insufficient to classify PBC and AIC as separate diseases. The ultimate answer to the question of whether AIC, defined as AMA-negative PBC with ANA or SMA, is a disease distinct from AMA-positive PBC with or without ANA will require a detailed comparison of etiologic factors and pathogenetic mechanisms, once they are elucidated. It is intriguing to consider the suggestion of Heathcote that the term autoimmune cholangitis be adopted to describe PBC with or without detectable AMA. However, it is improbable that the venerable term PBC will be supplanted. Hepatologists will probably continue to use the terms AIC and AMA-negative PBC interchangeably, with little risk of being misunderstood.

Antibodies, Antinuclear↗
PubMed1999

Cyclosporine therapy in patients with steroid resistant autoimmune hepatitis.

Autoimmune hepatitis is a form of chronic liver disease characterized by progressive hepatocellular inflammation, which usually responds to treatment with corticosteroids. However, 10% of patients with autoimmune hepatitis are refractory to corticosteroids and develop progressive liver disease and cirrhosis. We describe five patients with autoimmune hepatitis who did not respond to conventional corticosteroids and azathioprine therapy who were then treated with cyclosporine A. Cyclosporine A was started at 2-3 mg/kg/day and induced biochemical remission in four of five patients within 3 months. One of the four responders relapsed within 1 month of discontinuing cyclosporine on two occasions. Each time, liver tests promptly normalized after reinitiation of cyclosporine. Two responders were managed with cyclosporine alone. The single patient who did not respond to cyclosporine developed progressive liver failure, underwent orthotopic liver transplantation, and subsequently died of disseminated cytomegalovirus infection. Cyclosporine was generally well tolerated and none of the patients developed renal insufficiency. These data and review of 11 cases in the literature show that cyclosporine can induce remission of liver disease in patients with autoimmune hepatitis who are refractory to corticosteroids.

Adult↗
PubMed1998

Hepatitis B virus S mutants in liver transplant recipients who were reinfected despite hepatitis B immune globulin prophylaxis.

Long-term hepatitis B immune globulin (HBIG) has been shown to reduce hepatitis B virus (HBV) reinfection in patients transplanted for hepatitis B. The aim of this study was to determine the prevalence of HBV S gene mutations in liver transplant recipients who developed recurrent hepatitis B despite HBIG prophylaxis, and to determine if these mutations can revert after withdrawal of HBIG. The entire S gene sequences in pre- and posttransplant sera from 20 patients who developed recurrent hepatitis B despite HBIG prophylaxis were compared. Ten (50%) patients had 18 amino acid substitutions involving the 'a' determinant in the posttransplant samples. These mutations were absent in 93% of the pretransplantation clones analyzed. There was a significant correlation between the development of mutations in the 'a' determinant region and the duration of HBIG therapy. Most of the mutations result in changes in predicted antigenicity of the S protein. During follow-up, mutations in 14 (78%) of 18 affected codons in the 'a' determinant region reverted back to the pretransplantation sequences; only 1 codon had a de novo change after the withdrawal of HBIG. Two control patients who did not receive HBIG had no change in the 'a' determinant in their posttransplantation samples. These data support the hypothesis that mutations in the S gene were induced or selected by immune pressure exerted by HBIG. HBV S mutants may play a role in HBV reinfection in liver transplant recipients who received HBIG prophylaxis.

Adult↗
PubMed1997

Comparison of histopathology in acute allograft rejection and recurrent hepatitis C infection after liver transplantation.

Recurrent hepatitis C infection after orthotopic liver transplantation (OLT) is frequent and may occur as early as a few weeks postoperatively. Early histopathological features of recurrent hepatitis C virus (HCV) infection may be modified by immunosuppressive therapy and can be difficult to differentiate from acute allograft rejection (AAR). Thus, we retrospectively compared histopathological features of liver biopsy specimens from two carefully selected patient groups: one with unequivocal recurrent hepatitis C, the other with unequivocal AAR. Index biopsy specimens obtained at the time of the appearance of liver test abnormalities after OLT and all serial liver biopsy specimens (2 to 13 per patient) were assessed under code and scored semiquantitatively for 44 histopathological variables. The index biopsy specimens from patients with recurrent HCV infection and AAR index biopsies (AAR-Ib) differed significantly (P < .05) for 11 features (10 features were statistically associated with AAR and 1 with early recurrence of HCV infection). Statistically significant features associated with AAR included bile duct injury with overlapping nuclei, lymphocytic infiltrates and necrosis, endothelialitis, portal inflammatory infiltrates containing eosinophils and polymorphonuclear leukocytes, hepatocyte mitoses, and zone 3 canalicular cholestasis. In contrast, the only statistically significant feature associated with early recurrent HCV was sinusoidal dilatation. Stepwise discriminant analysis showed that the presence of eosinophils in the portal inflammatory infiltrate, bile duct necrosis, and bile duct lymphocytic infiltrates were independently associated with AAR. However, serial biopsy specimens from patients with recurrent HCV infection showed statistically significant progression in scores for portal inflammation, portal lymphoid aggregates, and lobular inflammation. We conclude that (1) multiple histopathological features are associated with AAR; (2) early recurrent HCV infection is characterized by elevated alanine aminotransferase levels, positive HCV RNA by polymerase chain reaction (PCR), and absence of diagnostic histopathological features; and (3) serial biopsies are needed to demonstrate progression of histopathological features of recurrent hepatitis C.

Acute Disease↗
PubMed1997

Morbidity and mortality of recurrent hepatitis C infection after orthotopic liver transplantation.

Through molecular virological testing it is now clear that HCV reinfection of the allograft is virtually universal in liver transplant recipients. Although histopathological recurrence of hepatitis C occurs in the majority of patients, it is absent in a substantial minority. To date, no prognostic factors, other than genotype 1b, have been identified that accurately predict these dissimilar outcomes. The natural history of recurrent hepatitis C varies. Historically, it has been regarded as generally benign. However, with increasing numbers of patients transplanted for hepatitis C it is now clear that a subgroup of patients develops severe progressive cholestatic hepatitis associated with allograft failure and death without retransplantation. Within 5 years following OLT, approximately 15-20% of patients progress to chronic active hepatitis and another 15-20% become cirrhotic. A minority of patients develop glomerulopathy or vasculitis, which are often associated with cryoglobulinaemia. The impact of immunosuppressive medications and rejection episodes on histopathological recurrence of progressive hepatitis C remains controversial and requires further studies. Although actuarial survival rates of patients transplanted for hepatitis C differ among transplantation centres, it appears that histopathological recurrence of hepatitis C does have an adverse impact on actuarial survival compared to the survival of patients transplanted for autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis and metabolic liver diseases. When allograft failure develops in patients with recurrent hepatitis C, retransplantation is indicated, even though recent reports indicate that mortality may be increased, especially with concurrent renal insufficiency.

Hepatitis C↗
PubMed1996

Hepatitis C virus is not recoverable from liver tissue in cryptogenic cirrhosis: failure to identify hepatitis C virus-RNA using reverse transcription-mediated polymerase chain reaction.

Polymerase chain reaction (PCR) has been used to study liver biopsy tissue in patients with known or suspected hepatitis C virus (HCV). Recent studies of cryptogenic cirrhosis using PCR have been based on study of sera, and HCV has not been shown. The failure to show HCV in patients so studied has left unanswered the question of whether or not patients with cryptogenic cirrhosis could still harbor the virus in the liver. The authors studied liver tissue, obtained at the time of orthopic liver transplantation from 10 patients clinically diagnosed as having end-stage liver disease without demonstrable origin, so-called cryptogenic cirrhosis, using reverse transcription (RT)-PCR to try to recover HCV-RNA. Formalin-fixed, paraffin-embedded tissue was used. For comparison, the authors also studied similarly obtained samples from 10 patients with typical hepatitis C-associated cirrhosis and 10 patients with end-stage liver disease resulting from autoimmune hepatitis. The authors recovered HCV-RNA from 9 of 10 livers from patients with cirrhosis resulting from HCV, and 3 of 10 livers from patients with autoimmune hepatitis. HCV-RNA was not recovered from any of the livers of the 10 patients designated as having cryptogenic cirrhosis.

Adolescent↗