Marc Deschenes

Use of Sequence Analysis of the NS5B Region for Routine Genotyping of Hepatitis C Virus with Reference to C/E1 and 5′ Untranslated Region Sequences

ABSTRACT Nucleotide sequence analysis of the NS5B region was performed to identify genotypes of 8,479 hepatitis C virus (HCV) RNA-positive patient samples collected in the Canadian province of Quebec. Genotypes could be determined for 97.3% of patients. Genotypes 1 to 6 were found in 59.4, 9.0, 25.7, 3.6, 0.6, and 1.8% of patients, respectively. Two isolates did not classify within the six genotypes. The subtype 1 distribution was 76.7% 1a, 22.6% 1b, and 0.7% others, while the subtype 2 distribution was 31.8% 2a, 47.6% 2b, 10.9% 2c, 4.1% 2i, and 5.6% others. Subtype 3a accounted for 99.1% of genotype 3 strains, while all genotype 5 samples were of subtype 5a. The subtype 4 distribution was 39.2% 4a, 15.4% 4k, 11.6% 4d, 10.2% 4r, and 23.6% others. The subtype 6 distribution was 40.4% 6e, 20.5% 6a, and 39.1% others. The 5′ untranslated region (5′UTR) sequences of subtype 6e were indistinguishable from those of genotype 1. All samples that did not classify within the established subtypes were also sequenced in C/E1 and 5′UTR. C/E1 phylogenetic reconstructions were analogous to those of NS5B. The sequences identified in this study allowed the provisional assignments of subtypes 1j, 1k, 2m, 2r, 3i, 4q, 6q, 6r, and 6s. Sixty-four (0.8%) isolates classifying within genotypes 1 to 6 could not be assigned to one of the recognized subtypes. Our results show that genotyping of HCV by nucleotide sequence analysis of NS5B is efficient, allows the accurate discrimination of subtypes, and is an effective tool for studying the molecular epidemiology of HCV.

Early allograft dysfunction after liver transplantation: A definition and predictors of outcome

BACKGROUND Poor graft function early after liver transplantation is an important cause of morbidity and mortality. We defined early allograft dysfunction (EAD) using readily available indices of function and identified donor, graft, and pretransplant recipient factors associated with this outcome. METHODS This study examined 710 adult recipients of a first, single-organ liver transplantation for non-fulminant liver disease at three United States centers. EAD was defined by the presence of at least one of the following between 2 and 7 days after liver transplantation: serum bilirubin >10 mg/dl, prothrombin time (PT) > or =17 sec, and hepatic encephalopathy. RESULTS EAD incidence was 23%. Median intensive care unit (ICU) and hospital stays were longer for recipients with EAD than those without (4 days vs. 3 days, P = 0.0001; 24 vs. 15 days, P = 0.0001, respectively). Three-year recipient and graft survival were worse in those with EAD than in those without (68% vs. 83%, P = .0001; 61% vs. 79%, P = 0.0001). A logistic regression model combining donor, graft, and recipient factors predicted EAD better than models examining these factors in isolation. Pretransplant recipient elevations in PT and bilirubin, awaiting a graft in hospital or ICU, donor age > or =50 years, donor hospital stay >3 days, preprocurement acidosis, and cold ischemia time > or =15 hr were independently associated with EAD. CONCLUSION Recipients who develop EAD have longer ICU and hospital stays and greater mortality than those without. Donor, graft, and recipient risk factors all contribute to the development of EAD. Results of these analyses identify factors that, if modified, may alter the risk of EAD.

Management of chronic hepatitis C: Consensus guidelines

Since the last consensus conference on the management of chronic viral hepatitis, a number of studies looking at modifications of the standard course of treatment have been published. These changes have been sufficiently substantive to warrant review to determine whether any changes in the recommended treatment algorithms are needed. A consensus development conference was held in January 2007, and the present document highlights the results of the presentations and discussion about these issues. It reviews the epidemiology of hepatitis C in Canada, treatment of acute hepatitis C and new algorithms in chronic hepatitis C, including retreatment of previous treatment failures. In addition, sections on management of hepatitis C in special populations have been updated. There is also a section on the use of hematopoietic growth factors to help manage patients on therapy. The document should be read in conjunction with the previous document to identify changes. Some recommendations made in the previous document remain and are not discussed here.

Transjugular intrahepatic portosystemic shunt (TIPS) versus endoscopic variceal ligation in the prevention of variceal rebleeding in patients with cirrhosis: a randomised trial

BACKGROUND AND AIMS The transjugular intrahepatic portosystemic shunt (TIPS) is a new therapeutic modality for variceal bleeding. In this study we compared the two year survival and rebleeding rates in cirrhotic patients treated by either variceal band ligation or TIPS for variceal bleeding. METHODS Eighty cirrhotic patients (Pugh score 7–12) with variceal bleeding were randomly allocated to TIPS (n=41) or ligation (n=39), 24 hours after control of bleeding. RESULTS Mean follow up was 581 days in the ligation group and 678 days in the TIPS group. The two year survival rate was 57% in the TIPS group and 56% in the ligation group (NS); the incidence of variceal rebleeding after two years was 18% in the TIPS group and 66% in the ligation group (p<0.001). Uncontrolled rebleeding occurred in 11 patients in the ligation group (eight were rescued by emergency TIPS) but in none of the TIPS group. The incidence of encephalopathy at two years was 47% in the TIPS group and 44% in the ligation group (NS). CONCLUSIONS TIPS did not increase the two year survival rate compared with variceal band ligation after variceal bleeding in cirrhotic patients with moderate or severe liver failure. It significantly reduced the incidence of variceal rebleeding without increasing the rate of encephalopathy.

Liver transplantation for incidental cholangiocarcinoma: Analysis of the Canadian experience

Cholangiocarcinoma is a biliary tumor, which not infrequently complicates primary sclerosing cholangitis. It carries a poor prognosis and, with the exception of carefully selected individuals in research protocols, contraindicates orthotopic liver transplantation. There has been some suggestion that cholangiocarcinomas incidentally discovered at the time of transplantation carry a better prognosis. The goal of this retrospective study was to perform a national review of outcomes after liver transplantation in Canadian recipients found to have incidental cholangiocarcinoma in their explanted native liver. Six of the seven liver transplant centers in Canada provided clinical and follow‐up information on all liver transplant recipients found to have incidental cholangiocarcinoma in their explants. The diagnosis or suspicion of cholangiocarcinoma prior to transplantation were exclusion criteria for this study. Ten individuals with cholangiocarcinoma were transplanted between 1996 and 2003. The median duration of follow‐up was 28 months. Eight of the 10 had PSC. All of the tumors were stage I or II. The 3‐year survival for these patients was 30%. The median time to recurrence was 26 months (95% confidence interval 13uu‐uu37), and the median time to death was 30 months (95% confidence interval 28uu‐uu53). In conclusion, although early survival of patients transplanted for incidental cholangiocarcinoma appears good, intermediate‐ and long‐term survival rates are not better than for individuals historically transplanted with known cholangiocarcinoma. Aggressive investigation for cholangiocarcinoma is mandated. Incidentally found tumours remain a difficult treatment problem, and prospective adjuvant chemo‐, radio‐, and immunotherapies should be investigated. (Liver Transpl 2005;11:1412–1416.)

Transplant immunosuppressive agents in non‐transplant chronic autoimmune hepatitis: the Canadian association for the study of liver (CASL) experience with mycophenolate mofetil and tacrolimus

Background: Conventional treatment of autoimmune hepatitis consists of either prednisone alone or in combination with azathioprine. Ten to 20% of patients do not respond to or are intolerant of this treatment. Novel drug treatments include immunosuppressive drugs such as tacrolimus (TAC), mycophenolate mofetil (MMF), methotrexate and cyclosporine. We describe a multi‐centre Canadian experience with MMF and TAC.

Management of chronic hepatitis B: Consensus guidelines

The present document presents the proceedings of the consensus development conference on the management of viral hepatitis held in January 2007 under the auspices of the Canadian Association for the Study of the Liver and the Association of Medical Microbiology and Infectious Disease Canada. Several new agents have become available since the last such document was published in 2004, and new information has become available to help assess risk of adverse outcomes and who should be treated. In addition, the participants at the meeting identified a number of structural barriers that exist uniquely in Canada and that prevent physicians from properly managing their patients. The conference discussed the selection of patients for treatment and the drugs that can be used to treat these patients, as well as the treatment of hepatitis B in special populations. The present document should be read in conjunction with the companion document on the management of chronic hepatitis C.

Peginterferon alfa-2a (40KD) plus ribavirin in chronic hepatitis C patients who failed previous interferon therapy

Background: The management of patients with chronic hepatitis C who have relapsed or failed to respond to interferon based therapies is an important issue facing hepatologists. Aims: We evaluated the efficacy and safety of peginterferon alfa-2a (40KD) plus ribavirin in this population by conducting a multicentre open label study. Patients: Data from adults with detectable serum hepatitis C virus (HCV) RNA who had not responded or had relapsed after previous conventional interferon or conventional interferon/ribavirin combination therapy were analysed. Methods: Patients were retreated with peginterferon alfa-2a (40KD) 180 µg/week plus ribavirin 800 mg/day for 24 or 48 weeks at the investigators’ discretion. The study was conceived before the optimal dose of ribavirin (1000/1200 mg/day) for patients with genotype 1 was known. The primary endpoint was sustained virological response (SVR), defined as undetectable HCV RNA (<50 IU/ml) after 24 weeks of follow up. The analysis was conducted by intention to treat. Results: A total of 312 patients (212 non-responders, 100 relapsers) were included. Of these, 28 patients were treated for 24 weeks and 284 for 48 weeks. Baseline characteristics between non-responders and relapsers were similar although more non-responders had genotype 1 infection (87% v 69%). Overall SVR rates were 23% (48/212) for non-responders and 41% (41/100) for relapsers. When data were analysed by genotype, SVR rates were 24% (61/253) in genotype 1 and 47% (28/59) in genotype 2/3. Conclusions: These results in a large patient cohort demonstrate that it is possible to cure a proportion of previous non-responders and relapsers by retreating with peginterferon alfa-2a (40KD) plus ribavirin.

Efficacy of mycophenolate mofetil combined with very low-dose cyclosporine microemulsion in long-term liver-transplant patients with renal dysfunction.

Background. Cyclosporine (CsA)‐induced renal dysfunction is common after liver transplantation. We evaluated the efficacy of tapering CsA to a very low dose and introducing mycophenolate mofetil (MMF) in long‐term liver‐transplant recipients with renal dysfunction. In addition, we assessed the impact of this strategy on calcineurin inhibition and on transforming growth factor (TGF)‐&bgr; levels. Methods. We prospectively enrolled 19 adult, longterm (>1 year) liver‐transplant recipients with a decreased creatinine clearance greater than 25% compared with the first month posttransplant. MMF was introduced, and CsA was tapered to 25 mg twice daily. Calcineurin inhibition and TGF‐&bgr; were measured at baseline and 3 months thereafter. Results. The CsA dose was tapered over 13±3 weeks. At 1‐year follow‐up, serum creatinine decreased from 141±24 to 105±22 μmol/L (P=0.002), creatinine clearance increased from 53±9 to 71±19 ml/min (P=0.02), and glomerular filtration rate increased from 40±13 to 64±18 mL/min (P=0.002). The incidence of acute rejection was 29%. Antihypertensive medications were discontinued in 71% of the patients. Although CsA levels decreased significantly, serum TGF‐&bgr; did not differ from normal controls, and calcineurin inhibition remained stable. The incidence of gastrointestinal sideeffects and leukopenia was 18% and 24%, respectively. Conclusion. In long‐term liver‐transplant recipients with renal dysfunction, the introduction of MMF followed by tapering of CsA to a very low dose resulted in a significant improvement in renal function. However, this strategy maybe associated with a risk of acute rejection. The clinical pertinence of measuring serum TGF‐&bgr; levels and calcineurin inhibition remains to be determined.

Clostridium difficile colitis: Increasing incidence, risk factors, and outcomes in solid organ transplant recipients

Background Clostridium difficile-associated diarrhea (CDAD) is an increasingly important diagnosis in solid organ transplant recipients, with rising incidence and mortality. We describe the incidence, risk factors, and outcomes of colectomy for CDAD after solid organ transplantation. Methods Patients with CDAD were identified from a prospective transplant database. Complicated Clostridium difficile colitis (CCDC) was defined as CDAD associated with graft loss, total colectomy, or death. Results From 1999 to 2010, we performed solid organ transplants for 1331 recipients at our institution. The incidence of CDAD was 12.4% (165 patients); it increased from 4.5% (1999) to 21.1% (2005) and finally 9.5% (2010). The peak frequency of CDAD was between 6 and 10 days posttransplantation. Age more than 55 years (hazard ratio [HR]: 1.47, 95% confidence interval [CI]=1.16–1.81), induction with antithymocyte globulin (HR: 1.43, 95% CI=1.075–1.94), and transplant other than kidney alone (liver, heart, pancreas, or combined kidney organ) (HR: 1.41, 95% CI=1.05–1.92) were significant independent risk factors for CDAD. CCDC occurred in 15.8% of CDAD cases. Independent predictors of CCDC were white blood cell count more than 25,000/&mgr;L (HR: 1.08, 95% CI=1.025–1.15) and evidence of pancolitis on computed tomography scan (HR: 2.52, 95% CI=1.195–5.35). Six patients with CCDC underwent colectomy with 83% patient survival and 20% graft loss. Of the medically treated patients with CCDC (n=20), the patient survival was 35% with 100% graft loss. Conclusions We have identified significant risk factors for CDAD and predictors of progression to CCDC. Furthermore, we found that colectomy can be performed with excellent survival in selected patients.