Joanne C. Imperial

Natural history of chronic hepatitis B and C.

Hepatitis B virus (HBV) affects more than 300 million individuals worldwide and in the United States approximately 1.25 million individuals are chronic carriers of HBV. The risk of becoming a chronic hepatitis B virus surface antigen carrier is dependent upon the mode of acquisition of infection as well as the age of the individual at the time of infection. For those individuals with high levels of viral replication, chronic active hepatitis with progression to cirrhosis, liver failure and hepatocellular carcinoma (HCC) is common and liver transplantation is an excellent treatment option for patients with end‐stage liver disease from HBV. Patients with chronic HBV infection should be screened periodically for hepatoma, although screening strategies have not been proven to prolong survival. Newer antiviral agents for the treatment of HBV are potent inhibitors of HBV‐DNA and their long‐term effect on the natural history of HBV is yet to be proven. The natural history of hepatitis C virus (HCV) infection is less well defined than that of chronic HBV. Certain patients who are chronic carriers of HCV may never develop extensive fibrosis, whereas others will progress to chronic active hepatitis with cirrhosis, HCC and end‐stage liver disease. Factors that influence the progression of HCV are those related to the host, including the age at acquisition of infection, gender and immune status, and the disease process is accelerated in patients who consume regular amounts of alcohol. Hepatocellular carcinoma develops frequently in patients with HCV infection and its overall incidence is increasing due to this chronic viral disease. Patients with HCV cirrhosis should be screened regularly for hepatoma and liver transplantation is an effective treatment option for those with end‐stage disease. The impact of antiviral therapy on the natural history of HCV is still to be determined and should be the focus of large clinical trials.

Treatment of Hepatic Failure Secondary to Isoniazid Hepatitis with Liver Transplantation

SummaryTwo patients with liver failure secondary to isoniazid hepatotoxicity were successfully treated with orthotopic liver transplantation. A 49-year-old man received isoniazid prophylaxis for a positive tuberculin test, and a 60-year-old woman was treated for active pulmonary tuberculosis with isoniazid, rifampin, and pyrazinamide. Both patients developed hepatic failure 4 and 1.5 months after initiation of antituberculous drug therapy, respectively. Liver transplantation was performed for progressive hepatic failure and was successful in both patients. The patient with active pulmonary tuberculosis was successfully treated with a modified antituberculous drug regimen while taking standard doses of immunosuppressive drugs after transplantation. In conclusion, liver transplantation is feasible and effective therapy for patients with isoniazid-induced hepatic failure, and active pulmonary tuberculosis may represent a relative rather than absolute contraindication to transplantation.

Resection versus transplantation for hepatocellular carcinoma.

Hepatocellular carcinoma is responsible for more than 1 million deaths per year worldwide and thus remains a challenging medical problem. It causes few or no symptoms and the tumour frequently reaches an enormous size by the time of diagnosis in countries where screening is seldom used. It is generally resistant to commercially available anti‐neoplastic agents and radiation therapy. The principal treatment continues to be resection, either partial or complete, with liver transplantation. However, less than one‐third of patients are surgical candidates for either resection or transplantation at the time of clinical presentation. This review will address the results observed following resection or transplantation for hepatocellular carcinoma.

A novel technique for endoscopic removal of expandable biliary Wallstent.

The placement of a metallic stent for the longterm management of benign biliary strictures is controversial.1-5 Once deployed, a metal stent is essentially irretrievable by endoscopic means, and when the stent becomes embedded in the submucosa, it cannot be removed even surgically.6 Patients with primary sclerosing cholangitis (PSC) have a reasonably long life expectancy and therefore are not good candidates for permanent metallic stent placement.1 We describe the first reported case of endoscopic removal of a metallic Wallstent (Schneider Inc., Minneapolis, Minn.) from the bile duct.

Does Asian race affect hepatitis B virus recurrence or survival following liver transplantation for hepatitis B cirrhosis

To assess whether Asian race is an independent variable affecting survival and hepatitis B virus (HBV) recurrence after liver transplantation, the results of 27 consecutive liver transplants performed between June 1994 and April 1997 for HBV cirrhosis were analysed. In the group of 13 Asians, 38% had associated hepatocellular carcinoma and 62% had positive hepatitis B virus early antigen (HBeAg) or elevated HBV‐DNA before transplant. Prophylactic hepatitis B immunoglobulin (HBIG) was administered perioperatively and long term at 4–6 weekly interval. Four patients with elevated HBV‐DNA received lamivudine before transplantation. The 3 year actuarial patient survival rate was 100% in both Asian and non‐Asian patients. Twenty‐six patients remained seronegative for hepatitis B virus surface antigen after transplantation. The incidence of post‐transplant HBV recurrence was similar: 0% in Asians compared with 7% in non‐Asians. There was no recurrence in the group of 12 patients who were HBV‐DNA or HBeAg negative pretransplant.

Management of post-liver-transplant biliary strictures : a work in progress

More than 80,000 liver transplantations have been performed in the United States since 1988, and the overall long-term survival rate has been favorable. Unfortunately, biliary complications occur in 11% to 38% of orthotopic liver transplant (OLT) recipients, threatening the viability of the graft. Specifically, biliary strictures are the most frequently described complication, occurring in 4% to 13% of patients after OLT surgery. The 2 biliary anastomoses performed during OLT surgery in the United States are choledochocholedochostomy (CC) and Roux-en-Y choledochojejunostomy (CDJ), with CC being the preferred method. However, patients diagnosed with extrahepatic biliary diseases such as primary sclerosing cholangitis or cholangiocarcinoma and children with biliary atresia routinely undergo Roux-en-Y CDJ. Marked size disparity between donor and recipient bile ducts favors Roux-en-Y CDJ as well. Posttransplantation strictures are categorized as either anastomotic or nonanastomotic. Hepatic artery thrombosis and prolonged graft cold ischemia time lead to nonanastomotic stricture formation from inadequate perfusion of the donor liver. Blood type incompatability, chronic rejection, recurrent disease, and cytomegalovirus infection are other causes of nonanastomotic strictures. Technical problems are the most frequent cause of anastomotic strictures, which comprise up to 85% of biliary strictures diagnosed after liver transplantation. In the early days of OLT, surgical revision of bile duct anastomoses was the preferred approach to treatment of biliary complications, whereas more severe complications would frequently require retransplantation. T-tube insertion during creation of the biliary anastomosis was commonly performed in an attempt to prevent strictures. Randomized studies comparing transplantations performed with a Ttube to those without a T-tube found no difference in stricture development. Higher complication rates, however, were noted within the T-tube groups. Construction of biliary anastomoses over an internal stent was a less commonly performed prophylactic measure, but multiple complications, including leaks, obstruction, hemobilia, and death, led to the discontinuation of this practice.