Liver transplantation for hepatitis C-associated cirrhosis in a single Australian centre: referral patterns and transplant outcomes

The rise and fall of infectious diseases: Australian perspectives, 1914-2014

Australia has been fortunate in its experience with infectious diseases over the past century. By the 1960s, many communicable diseases were controlled through a combination of high living standards, progressive adoption of vaccines and antimicrobial treatment. Australian medical scientists have made substantial contributions to the understanding of many historically significant communicable diseases and global initiatives for control. New challenges have emerged as previously unrecognised viral infections have emerged, and microbial resistance to antibiotics has developed in many old pathogens. Ongoing evolutionary forces, both environmental and social, change the balance between humans and microbes. The effects of these forces are most sorely felt in poor countries and communities.

Recent advances in discovery and development of promising therapeutics against hepatitis C virus NS5B RNA-dependent RNA polymerase

Lack of highly effective and safe therapeutics for hepatitis C virus (HCV) infection provides an opportunity as well as a challenge to discover novel and potent anti-HCV drugs. HCV NS5B RNA-dependent RNA polymerase (RdRp) is responsible for viral genome replication and thus constitutes a valid target for therapeutic intervention. To date, numerous HCV NS5B RdRp inhibitors have been discovered. This review focuses on the recent advances in discovery, mechanism of action studies and biological characterization of several distinct classes of potent inhibitors for NS5B RdRp. The clinical efficacy and developmental status of several promising compounds are also outlined.

Liver transplantation for alcoholic liver disease

Patients with end-stage alcoholic liver disease should be considered for liver transplantation. A careful pretransplant evaluation must be undertaken to assess for both medical and psychiatric factors that will continue to require attention following transplantation. Although most programs require at least 6 months of ethanol abstinence before consideration of liver transplantation, there is little evidence that this conclusively predicts a reduction in recidivism. Most programs continue to exclude those with alcoholic hepatitis. Postoperatively, attention to psychiatric issues, recidivism, compliance, and assessment for tumors, especially squamous cell carcinomas, should be undertaken.

Immunopathogenesis of hepatitis C virus infection

Hepatitis C virus, a recently identified member of the family Flaviviridae, is an important cause of chronic viral hepatitis and cirrhosis. There are similarities in the nature of the immune response to this pathogen with immunity in other flavivirus and hepatotropic virus infections, such as hepatitis B. However, the high rate of viral persistence after primary hepatitis C infection, and the observation that neutralizing antibodies are not protective, would suggest that there are a number of important differences between hepatitis C, other flaviviruses, and hepatitis B. The phenomenon of quasispecies evolution and other viral factors have been proposed to contribute to immune evasion by hepatitis C virus. In the face of established persistent infection, virus-specific cytotoxic T lymphocytes may exert some control over viral replication. However, these same effectors may also be responsible for the progressive liver damage characteristic of chronic hepatitis C infection. The nature of protective immunity, including the role of innate immune responses early after hepatitis C exposure, remains to be defined.

Liver transplantation for alcoholic cirrhosis: long term follow-up and impact of disease recurrence

BACKGROUND

Alcoholic liver disease has emerged as a leading indication for hepatic transplantation, although it is a controversial use of resources. We aimed to examine all aspects of liver transplantation associated with alcohol abuse.

METHODS

Retrospective cohort analysis of 123 alcoholic patients with a median of 7 years follow-up at one center.

RESULTS

In addition to alcohol, 43 (35%) patients had another possible factor contributing to cirrhosis. Actuarial patient and graft survival rates were, respectively, 84% and 81% (1 year); 72% and 66% (5 years); and 63% and 59% (7 years). After transplantation, 18 patients (15%) manifested 21 noncutaneous de novo malignancies, which is significantly more than controls (P=0.0001); upper aerodigestive squamous carcinomas were overrepresented (P=0.03). Thirteen patients had definitely relapsed and three others were suspected to have relapsed. Relapse was predicted by daily ethanol consumption (P=0.0314), but not by duration of pretransplant sobriety or explant histology. No patient had alcoholic hepatitis after transplantation and neither late onset acute nor chronic rejection was significantly increased. Multiple regression analyses for predictors of graft failure identified major biliary/vascular complications (P=0.01), chronic bile duct injury on biopsy (P=0.002), and pericellular fibrosis on biopsy (P=0.05); graft viral hepatitis was marginally significant (P=0.07) on univariate analysis.

CONCLUSIONS

Alcoholic liver disease is an excellent indication for liver transplantation in those without coexistent conditions. Recurrent alcoholic liver disease alone is not an important cause of graft pathology or failure. Potential recipients should be heavily screened before transplantation for coexistent conditions (e.g., hepatitis C, metabolic diseases) and other target-organ damage, especially aerodigestive malignancy, which are greater causes of morbidity and mortality than is recurrent alcohol liver disease.

Hepatitis C infection in children: a Melbourne perspective

OBJECTIVE

To examine the clinical spectrum of hepatitis C virus (HCV) infected children in our care by determining presentation, mode of acquisition, degree of co-infection, biochemical evidence of persisting hepatitis and treatment outcome.

METHODOLOGY

A retrospective review of the medical records of all children attending the Royal Children's Hospital, Melbourne, between 1990 and 1998, who had antibodies to HCV infection detected. Detailed clinical information, investigations and the results of treatment were extracted from the clinical notes.

RESULTS

A total of 94 children (age range 2 weeks to 19.7 years) were identified, of whom nine had passive transfer of maternal antibodies from HCV-positive mothers and were excluded from analysis. Sixty-seven children (79%) were infected by transfusion of blood or blood products. Perinatal transmission occurred in 11 children (13%), and six children (7%) had a history of i.v. drug abuse. The majority of children were asymptomatic at presentation. Of the 65 patients tested for HCV-ribonucleic acid, 43 (66%) were positive. Fifty-seven cases had serial alanine aminotransaminase (ALT) measurements over a mean of 28 months. Of these, 38 (67%) had an abnormal ALT. Ten cases (12%) were co-infected with hepatitis B virus, HIV or both. Of 12 patients treated with interferon, four responded with normalisation of ALT from 3 to 12 months post-commencement of therapy.

CONCLUSIONS

Although HCV was largely an asymptomatic condition in our clinic population, more than half the patients had biochemical evidence of ongoing liver damage. Given the chronicity of this infection in the majority of patients and the long-term risks of cirrhosis and hepatocellular carcinoma, children with HCV infection represent a high-risk group worthy of regular follow up.

Hepatitis C in injecting drug-using women during and after pregnancy

BACKGROUND

A high proportion of female injecting drug users (IDU) have evidence of hepatitis C virus (HCV) infection. We undertook a prospective study of patients attending a clinic for pregnant IDU to determine the impact of pregnancy on the course of HCV infection and whether pregnancy is affected by HCV infection.

METHODS

One hundred and thirty-one IDU were recruited and followed up with liver function tests, HCV serology and HCV-RNA tests.

RESULTS

Of 131 patients, 125 had HCV antibodies (anti-HCV positive) at delivery, and of these 62% were HCV-RNA positive. The anti-HCV-negative women were younger and had a shorter duration of drug use than the anti-HCV-positive women. There were no differences between viraemic and non-viraemic women with respect to age, ethnicity, duration of injecting drug use, methadone maintenance dose, hepatitis B exposure or reported high-risk behaviour. Alanine aminotransferase (ALT) levels were higher and the proportion with ALT > 55 IU/L higher in viraemic women. Viraemia persisted in all 55 women who were viraemic at term. Eleven had an ALT flare post-partum that was unrelated to viral load and was clinically unsuspected. Four had concurrent elevated gamma-glutamyltranspeptidase and were considered to be drinking alcohol at hazardous levels. Four of 23 women who were HCV-RNA negative at term became positive during follow up.

CONCLUSIONS

Pregnancy does not adversely affect the course of hepatitis C. A modest rebound in ALT levels, but not HCV-RNA, occurs after delivery in some viraemic women. This supports the theory that immune mechanisms rather than direct viral cytopathology are involved in hepatocyte injury during HCV infection. Hepatitis C infection did not influence pregnancy complications and outcomes.

Which patients with hepatitis C develop liver complications?

To identify variables that are independent predictors of adverse outcomes in chronic hepatitis C, we analyzed a cohort of 455 patients followed for a median of 4.7 years. Associations were sought between demographic and behavioral factors, hepatitis C virus (HCV) genotype, liver histology and liver tests at entry, and development of liver complications, hepatocellular carcinoma (HCC), hepatic transplantation and liver-related death. Independent predictors were identified by multivariate analysis. The following were associated with a significantly higher rate of liver complications: age; birth in Asia, Europe, Mediterranean region, or Egypt; transmission by blood transfusion or sporadic cases; HCV genotypes 1b and 4 (compared with 1/1a); fibrosis stage 3 or 4 (cirrhosis); serum albumin; bilirubin; prothrombin time; and alpha-fetoprotein. However, the only independent predictors of liver-related complications were sporadic transmission (P <.001), advanced fibrosis (P =.004), and low albumin (P <.001). The corresponding independent risk factors for HCC were male gender (P =. 07), sporadic transmission (P <.001), and albumin (P <.001); bilirubin (P =.02) was an additional predictor of transplantation or liver-related death. It is concluded that only patients with advanced hepatic fibrosis or cirrhosis, are at risk of developing hepatic complications of chronic hepatitis C during 5-year follow-up. Among such patients, abnormalities in serum albumin, bilirubin, or prothrombin time indicate a high probability of complications. Patients without definite risk factors for HCV (sporadic cases) are at higher risk of complications, possibly because of interaction between older age, duration of infection, country of birth, and HCV genotypes 1b and 4.

How much does alcohol contribute to the variability of hepatic fibrosis in chronic hepatitis C?

In order to determine the contribution of alcohol intake to the severity of hepatic fibrosis in patients with chronic hepatitis C, we studied associations between various levels of alcohol intake, other demographic variables and semiquantitative liver histology in 434 cases of chronic hepatitis C. Clinical, demographic and disease-related data were entered into a relational database. Liver histology was scored according to Scheuer. The average daily alcohol intake for the year preceding liver biopsy (recent exposure) and for earlier periods (past exposure) was categorized into five levels of intake. One-third of patients gave a history of alcohol intake that had exceeded 40 g/day for at least 5 years. By univariate analysis, age, but not recent or past alcohol intake or other baseline variables, was associated with portal score (r = 0.14, P = 0.004), fibrosis score (r = 0.46, P < 0.001), total Scheuer score (r = 0.35, P < 0.001). However, by multivariate analysis, age (P < 0.001), past (but not present) alcohol intake (P < 0.001) and birth in Egypt (P = 0.006) were independently associated with fibrosis score. Age, past alcohol and birth place in Egypt contributed 27% to total variance of the hepatic fibrosis score, while age alone accounted for 23%. Age also independently predicted portal activity (P = 0.02) and total Scheuer score (P < 0.001), whereas past alcohol intake correlated with total Scheuer score (P = 0.002) but not with other histological indices. A separate multivariate analysis was performed on a more homogeneous subgroup of 196 patients who acquired hepatitis C by injection drug use. In this subgroup, age (P < 0.05) and past alcohol (P < 0.05) were independently associated with fibrosis score. In both the overall and subgroup analyses, there was a threshold level of past alcohol intake (>80 g/day) beyond which the risk of fibrosis increased significantly. It is concluded that toxic levels of alcohol exposure for at least 5 years accentuate hepatic fibrosis in hepatitis C but the influence of alcohol appears to be minor compared with age and other variables and is exerted only at toxic levels of intake.