Howard C. Thomas

Molecular Cloning and Disease Association of Hepatitis G Virus: A Transfusion-Transmissible Agent

An RNA virus, designated hepatitis G virus (HGV), was identified from the plasma of a patient with chronic hepatitis. Extension from an immunoreactive complementary DNA clone yielded the entire genome (9392 nucleotides) encoding a polyprotein of 2873 amino acids. The virus is closely related to GB virus C (GBV-C) and distantly related to hepatitis C virus, GBV-A, and GBV-B. HGV was associated with acute and chronic hepatitis. Persistent viremia was detected for up to 9 years in patients with hepatitis. The virus is transfusion-transmissible. It has a global distribution and is present within the volunteer blood donor population in the United States.

MUTATION PREVENTING FORMATION OF HEPATITIS B e ANTIGEN IN PATIENTS WITH CHRONIC HEPATITIS B INFECTION

Some patients with chronic hepatitis B virus (HBV) infection are HB e antigen (HBeAg) negative, have circulating HBV particles, and often have especially severe chronic hepatitis. To test the hypothesis that the absence of HBeAg production may be due to a change in the nucleotide sequence of the pre-core region of the genome, 18 Greek and 3 non-Greek patients positive for HB surface antigen underwent direct sequencing of HBV-DNA amplified from sera. In 7 out of 8 HBeAg negative patients, two mutations (guanosine to adenosine) were found in the terminal two codons of the pre-core region, giving the sequence TAGGACATG. The remaining patient had the first mutation only. The sequence TGGGGCATG was found in 4 of 5 of the HBeAg positive patients. The first mutation results in a translational stop codon that is predicted to result in failure to produce HBeAg. The rest of the pre-core region in the HBeAg negative patients was otherwise homologous to that of the HBeAg positive patients and to known sequences.

Vaccine-induced escape mutant of hepatitis B virus

In southern Italy, 44 contacts of hepatitis B virus carriers, including infants of carrier mothers, became HBsAg positive despite passive and active immunisation according to standard protocols. In 32 of these vaccinees infection was confirmed by the presence of additional markers of viral replication. In 1 infant, serious disease occurred. The virus from this patient is an escape mutant with a different sequence from that of the isolate from the mother. A point mutation from guanosine to adenosine at nucleotide position 587 resulted in an aminoacid substitution from glycine to arginine in the highly antigenic a determinant of HBsAg. This mutation is stable: it is present in an isolate from the child 5 years later. In some of these patients, including this child, the a determinant, to which a large part of the vaccine-induced immunity is directed, has been partly lost. Binding to HBsAg of a monoclonal antibody, previously mapped to the region of the mutation, was reduced in the child relative to that of the mother.

Guidelines for the diagnosis and treatment of cholangiocarcinoma: consensus document

### 1.1 Development of guidelines There is currently no clear national consensus for the optimal diagnosis and treatment of cholangiocarcinoma. The need for these guidelines was highlighted following the annual meeting of the British Association for the Study of the Liver (BASL) in September 2000. During their development these guidelines were presented at a BASL Liver Cancer Workshop in January 2001. They were also circulated to BASL members and the Liver Section of the British Society of Gastroenterology (BSG) Committee members, including gastroenterologists, hepatologists, gastroenterological surgeons, pathologists, radiologists, and epidemiologists for comments before the final consensus document was drawn up. ### 1.2 Strategy The guidelines are based on comprehensive literature surveys including results from randomised controlled trials, systematic reviews and meta-analyses, and cohort, prospective, and retrospective studies. On issues where no significant study data were available, evidence was obtained from expert committee reports or opinions. Where possible, specific recommendations have been graded, based on the quality of evidence available (section 2.4). ### 1.3 Context and intent These guidelines are intended to bring consistency and improvement in the patient’s management from first suspicion of cholangiocarcinoma through to confirmation of the diagnosis and subsequent management. As stated in previous BSG guidelines, patient preferences must be sought and decisions made jointly by the patient and health carer, based on the risks and benefits of any intervention. Furthermore, the guidelines should not necessarily be regarded as the standard of care for all patients. Individual cases must be managed on the basis of all clinical data available for that case. The guidelines are subject to change in light of future advances in scientific knowledge. Mortality rates from intrahepatic cholangiocarcinoma have risen steeply and steadily over the past 30 years and since the mid 1990s more deaths have been coded annually in England and Wales as being due to this tumour than to hepatocellular carcinoma.1 In 1997 and …

Increase in primary liver cancer in the UK, 1979–94

1 McCarthy M. Bio-engineered tissues move towards the clinic. Lancet 1996; 348: 466. 2 Meszaros L. Manufactured living tissue helps heal venous ulcers. Dermatol Times 1995; July: 15. 3 Eaglstein WH, Iriondo M, Laszlo K. A composite skin substitute for surgical wounds: a clinical experience. J Derm Surg 1995; 21: 1–5. 4 Mechcatie E. FDA expedites review of synthetic skins. Skin and Allergy News 1995; Aug: 4.

Changing international trends in mortality rates for liver, biliary and pancreatic tumours.

BACKGROUND/AIMS The age-standardized mortality rate for hepatocellular carcinoma is increasing in several countries. However, in England and Wales we previously reported an increase in mortality rates from intrahepatic cholangiocarcinoma. Trends in cholangiocarcinoma in most other industrialized countries are unknown. To further study trends in hepatobiliary and pancreatic tumours, we analysed mortality data from the United States, Japan, Australia and Europe. METHODS Age-standardized mortality rates for men and women for subcategories of liver tumours, tumours of the gall bladder and extrahepatic biliary tree and pancreas from 1979 to 1998 were obtained from the World Health Organization mortality database. RESULTS We confirmed previously reported increases in hepatocellular carcinoma, but also found increases in other countries, particularly Australia (3-year average rise from 1.20 to 2.27, men). Mortality for intrahepatic cholangiocarcinoma increased in men in all countries studied, with the largest increases in Australia (from 0.10 to 0.70) and England and Wales (from 0.20 to 0.83). CONCLUSIONS We present a hitherto unreported rise in age-standardized mortality rates from intrahepatic cholangiocarcinoma across four continents. The cause remains uncertain. An impact on the observed trends of improved diagnostic techniques and death certificate misclassification cannot be completely ruled out. Future research should include epidemiological studies to examine possible case-clustering and investigation of potential aetiological and host factors.

Association between an MHC class II allele and clearance of hepatitis B virus in the Gambia.

BACKGROUND The course of hepatitis B virus (HBV) infection does not appear to be determined by variations in viral virulence and may be influenced by the host immune response. We studied the distribution of human leukocyte antigens in children and adult men in the Gambia who spontaneously recovered from HBV infection as compared with the distribution of these antigens in subjects with persistent infection. METHODS In a two-stage, case-control study, we analyzed the frequency of MHC class I antigens and class II haplotypes in people with either transient or persistent HBV infection. MHC class I typing was performed by microlymphocytotoxicity assays. MHC class II typing was performed with analysis of restriction-fragment-length polymorphisms (RFLPs), supplemented by other techniques. RESULTS In the first stage (the study of children up to the age of 10 years), the RFLP pattern 25-1, which includes the class II allele HLA-DRB1*1302, was found in 58 of 218 subjects with transient HBV infection (26.6 percent) and 30 of 185 subjects with persistent infection (16.2 percent) (relative risk of carrying the 25-1 pattern in the persistently infected group as compared with the transiently infected group, 0.53; 95 percent confidence interval, 0.32 to 0.90; P = 0.012). In the second stage (the study of adults), HLA-DRB1*1302 was found in 50 of 195 subjects with transient HBV infection (25.6 percent) and in 3 of 40 subjects with persistent infection (7.5 percent) (relative risk, 0.24; 95 percent confidence interval, 0.04 to 0.80; P = 0.012). The RFLP pattern 13-2, which includes the class II allele DRB1*1301, was less frequent in children with persistent infection than in those with transient infection, an association that was neither confirmed nor excluded by the data on adults. Possible associations with HLA class I antigens found in children were not supported by the data on adults. CONCLUSIONS The MHC class II allele DRB1*1302 was associated with protection against persistent HBV infection among both children and adults in the Gambia.

Ribavirin treatment for patients with chronic hepatitis C: results of a placebo-controlled study

BACKGROUND/AIMS Small, uncontrolled studies of ribavirin for patients with chronic hepatitis C have reported efficacy in chronic hepatitis C. We have evaluated the efficacy and safety of a 24-week course of oral ribavirin in patients with chronic hepatitis C, compared to placebo. METHODS A total of 114 patients were randomised to ribavirin or placebo. Ribavirin was administered in doses of 1000 or 1200 mg/day for 24 weeks. Efficacy was determined in the intention-to-treat population: 76 received ribavirin and 38 placebo. RESULTS Ribavirin was significantly more effective than placebo in reducing and normalising serum ALT levels: 42/76 (55%) of ribavirin-treated patients vs 2/38 (5%) placebo recipients had either normalisation of the ALT levels or a reduction from baseline of at least 50% (p < 0.001). ALT levels were normal in 22/76 (29%) of ribavirin-treated patients vs 0/38 placebo recipients (p < 0.001). Twenty-four weeks after stopping ribavirin, the majority of patients had abnormal ALT levels. There was no difference between the treatment groups in reduction or disappearance of HCV-RNA levels. HCV RNA disappeared during treatment in 3% of ribavirin-treated patients and 3% of placebo recipients. More ribavirin than placebo patients showed improvement in total Knodell score (45% vs 31%), but these differences were not statistically significant. Analysis of each component of a histology activity index revealed no statistically significant differences between treatment groups. Ribavirin patients had fewer lymphoid aggregates than did placebo recipients at the post-treatment assessment (p = 0.05). Ribavirin was associated with reversible haemolytic anaemia: a fall in haemoglobin occurred in 3% of placebo- and 32% (25/78) of ribavirin-treated patients, respectively (p < 0.001). CONCLUSIONS These data indicate that ribavirin was no more effective than placebo in reducing or eliminating HCV-RNA levels, and was not significantly more effective than placebo in improving hepatic histology after 6 months of treatment. The role of a 6-month treatment of chronic hepatitis C with ribavirin alone, without a significant effect on HCV RNA, is therefore limited.

Guidelines for the diagnosis and treatment of cholangiocarcinoma: an update.

The British Society of Gastroenterology guidelines on the management of cholangiocarcinoma were originally published in 2002. This is the first update since then and is based on a comprehensive review of the recent literature, including data from randomised controlled trials, systematic reviews, meta-analyses, cohort, prospective and retrospective studies.

Influence of MHC class II genotype on outcome of infection with hepatitis C virus

BACKGROUND The outcome of infection with hepatitis C virus (HCV) varies substantially among individuals. Host genetic factors are likely to give rise to some of this variability. Polymorphisms in the MHC class II loci may influence the outcome of HCV infection; however, reports of MHC class II allele associations have been inconsistent. We aimed to confirm these associations in a cohort of European patients with different clinical outcomes. METHODS The distribution of MHC class II alleles was compared between patients with self-limiting infection (n=85) and matched patients with persistent infection (n=170); between patients with mild (n=321) and severe (n=321) histological injury; and between patients who responded to interferon (n=96) and those who did not (n=192). The results of these comparisons were confirmed with a second-stage study of self-limiting infection (n=52) versus persistent infection (n=152). FINDINGS Self-limiting HCV infection was associated with HLA-DRB1*1101 (odds ratio 2.14 [95% CI 1.11-4.12]; p=0.013) and HLA-DQB1*0301 (2.22 [1.24-3.96], p=0.004). Persistent HCV infection was associated with HLA-DRB1*0701 (2.04 [1.03-4.17], p=0.027), and HLA-DRB4*0101 (2.38 [1.29-4.35], p=0.002). These results were confirmed in the second-stage study. No significant associations (p<0.05 after Bonferroni correction) were found between MHC class II alleles and severe histological injury or response to interferon therapy. INTERPRETATION Specific MHC class II alleles influence susceptibility or resistance to persistent HCV infection.