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Liver transplant for viral hepatitis
JournufofHepatology, 1991; 13(Suppl. 4): S134-S137 @J1991Elsevier Science Publishers B.V. All rights reserved.0168-8278/91/$03.50
s134
HEPAT 01073
Lives tram
atitis
lant for viral
ecurrence of reinfection A. Smedile’,
A. Marzano’, P. Farci*, E. Chiaberge’, F. Rosina’, M. Durazzo3, G. Verme
M. Abate’,
’ , F.
A. Ottobrelli’, M.R. izze tto3
‘Division of Gastroenterology, Molinette Hospital, Torino, Italy, ‘Laboratory of Infectious Diseases, Bethesda, United States of America and **hstituteof Intental Medicine, University of T&-in, Turin& kaly
transplantation has dramatically changed the life prospects of patients with terminal liver disorders. Progress in surgical methods and the use of potent antirejection treatment means that over 80% of those patients, whose life expectancy would otherwise have been very short, will now survive and be able to lead normal lives. Throughout the 1980s grafting has been progressively extended to now cover virtually all causes of liver damage (1). Patients with liver disorders of viral origin, however, are still exposed to the danger of graft reinfection: in those with type B hepatitis this risk and the ensuing risk of graft disease are so high that the decision to transplant in these cases has become controversial (2). The epidemiological problem is formidable, as batients with terminal viral cirrhosis or fulminant hepatitis are often young, i.e., they would normally be the best candidates for liver transplantation, and they account for the majority of cases requiring grafting in areas, such as the Mediterranean Basin, where viral hepatitis infections are hyperendemic. In recent years the problem of reinfection has led to interest in defining the virology of patients before grafting. This means that the risk of reinfection may be correlated with the various types of viral infection. It has also prompted a number of pretransplant prophylactic precautions and posttransplant treatment. This report summarizes how things stand at the beginning of the 1990s. The advent
of liver
Hepatitis B virus reinfection
In patients with hepatitis B the risk of reinfection is Correspondence:
very high; the source of reinfection is free virus in plasma or hidden in non-hepatic cells. Reinfection by the HBV is almost invariably accompanied by the recrudescence of hepatitis in the graft; the course of the recurrent disease often recapitulates the natural history of the original disease but may in some patients run an accelerated course to cirrhosis in a matter of a few months. While the medical sequelae of the infection can be mild and inapparent in the short term, within a few years from transplantation most of the HBV-reinfected patients experience serious liver dysfunction. In a series collected in Pittsburgh over the last decades, which accounts for the largest number of HBsAg carriers transplanted in the world, the complications related directly or indirectly to HBV reinfection have significantly reduced the life expectancy of the transplanted carriers compared to those candidates protected from HBV by the presence of spontaneous anti-HBs (3). Detailed analysis of the reinfection risk has shown that this depends above all on three factors: (i) the clinical type of HBV disease leading to transplantation; (ii) the original type of HBV infection; and (iii) whether or not the patient was given specific prophylaxis before grafting. Hi3V
presentation
Liver transplantation has been performed in patients with end-stage post-hepatitis B cirrhosis and fulminant hepatitis (FH). The latter has been considered an absolute condition for liver transplant because the immediate prognosis is very poor. The results achieved with FH have produced l-year survival rates of 5670% in many series published in Europe and North America (4,5). In
AmoninaSmedile.M.D., Division of Gastroenterology, Ospedale Molinette, C.so Bramante 88, 10126 Torino, Italy.
GIVER TRANSPLANT
AND REINFE~IQN
the previous series, when t aged medically, the s ival rate was less than 10% (6). Most of the cases acute liver failure had a viral a predominant infection by etiology patitis worldwide. and NA Vast surgical experience has been gained in Pittsburgh, North America and Villejuif, France. In Pittsburgh it was at patients transplanted for chronic sAgpositive lives disease showed a high risk U; reinfection, is incidence was relatively low for patients who underwent liver transplant for fulminant liver failure. Indeed out of eight patients who underwent emergency only one died. The remaining patients are QLT for alive and ;e not been reinfected 20 months after the operation. A similar experience was r in a series of 21 liver transplants for V). The rate of reinfe l/4 in patients with finding may be related to the massive necrosis of infected hepatocytes and early elimination of viremia which is characteristic of FH. During the fulminant course, serological markers of I-I V infection are usually not found. By contrast, patients with chronic HBV infection and stable viremia have a higher risk of reinfection. possible that in this chronic status of infection DNA sequences, in addition to being liver, are also harbored in extrahepatic tissues such as mononuclear blood cells and reactivated later on (7). Pretransplant virological status
The subtype of chronic I-IBV hepatitis in the recipients is a major factor influencing the rate of reinfection. Overall it has been observed that in patients analyzed before liver transplant those with chronic anti-HBe-positive hepatitis had a lower incidence of reinfection compared to those with HBeAg-positive hepatitis (8). Although liver transplant in patients with HBsAg-positive cirrhosis has been performed since the initial years of liver grafting, at the beginning patients were not divided according to their replicative status as detected by molecular hybridization assay (HBV DNA positive or HBV DNA negative) which is considered a more reliable diagnostic test than testing for the hepatitis B e antigen/antibody system. In a recent study conducted at Villejuif, patients were revaluated according to HBV replication. Patients who were HBV DNA positive had a much greater risk of HBsAg recurrence than patients who were HBV DNA negative (96% vs. 29%) (9). In our series of seven patients transplanted for HBV cirrhosis, six out of seven were reinfected within 2 years. Recurrence of liver disease in the graft was the rule with episodes of acute hepatitis leading to chronic hepatitis and cirrhosis. The
8135
antibody since even in there are subliminal levels o are revealed using sensitive assays such as cation methods (10). Thus, the pre-0I.T status is not relevant in predicting the recurren
virologic aspects which could be relevant in the recurrence of disease. Non-tral~splanted patients affected by this subtype of chronic hepatitis often show a point mutation at the 1894 nucleotide site which renders the core g synthesize the ‘e’ protein by producing a This mutation generates a mutant po virions that can be selected during the The predominance of this mutant, for reasons that are as yet unclear. can be selected in the reinfection of the new graft by reproducing the typical V infection or a more rapid and severe chronic hepatitis. It is possible t termine the ratio between these two populations of virions by using an oligonucleotide assay. In five cases studied we showed that the wild-type prevailed in two eAg-minus mutant in two other cases and cases, the a mixture of both was present in the remaining patient. An extensive analysis of transplanted patients is necessary before any conclusions may be drawn. In one patient who underwent liver transplant for cirrhosis B a complete characterization by the sequencing of amplified DNA has recently been reported (12). Prevention of HBV by immunoprophylaxis
The risk of reinfection has stimulated the use of a number of preventive measures, such as pretreatment of liver recipients with antivirals, HBV vacciuatton and passive prophylaxis with immunoglobulins against HBV (13). However, neither the antivirals nor vaccination have proved effective. The administration of HBIg over the short term was likewise disappointing, but promising results have recently been reported with protocols providing this prophylaxis over a long period (14). The experience of the Hannover group in Germany and of the Villejuif group in France indicates that substitution therapy with 10 000 IV/l of HBIg during the anhepatic phase plus 10 000 additional units for the next 6 to 8 days followed by periodical mainteuance doses to maintain the titre of anti-HBs over 100 UIA, is effective in preventing recurrence in patients who test negative prior to
A. SMEDILE et al.
S136 grafting for HBV-DNA by ordinary hybridization assays. Unfortunately, this prophylaxis is not effective in HBVDNA-positive patients, for whom no effective form of prevention has yet been devised. HDV reinfection Hepatitis type D also presents a high risk of reinfection with a variable expression of liver disease recurrence. The reinfection rate after OLT for cirrhosis due to HDV has been reported to be in the range of 77% and 86% in two series from Italy-Belgium and France (1215). Recurrence of liver disease varied between 52-28% in the two series. The pattern of HDV reinfection was peculiar in this setting, opening up new insights into the pathogenesis of HDV infection. The transplant model revealed that HDV infection is precocious, sometimes only a few days after transplant. The virus is to be found in the hepatocytes where it remains for months and hepatitis devetops only when there is a full expression of HBV markers. This suggests that the helper virus plays an important role in the recurrence of hepatitis. In our series of 31 patients transplanted for HDV cirrhosis there are five patients who have not yet been reinfected after 8 months to 2 years of follow-up as diagnosed by hybridization assays. The technique of PCR for HDV RNA has recently revealed two additional cases showing a subliminal replication, without signs of hepatitis. The recurrence of hepatitis in the allograft was similar to HDV infection in non-transplanted patients, with a rapid progression to chronic hepatitis and cirrhosis in a shorter period of time (6 months to 1 year). What role HBV plays in the rapid progression of liver disease is still unknown.
HCV reinfection Liver transplants have been performed in many patients who have been classified as having NANB or cryp-
cirrhosis. In these cases diagnostic assays for the hepatitis C virus (HCV) were carried out in retrospect in order to determine the prevalence of this infection in pretransplant sera and to study the recurrence of HCV infection and disease. In our series of 27 cases we found a high percentage of HCV infection in cryptogenic cirrhosis (82%), which is a percentage that is similar to those reported in many epidemiological studies (16). The rate of reinfection correlated well with the presence of HCV RNA preoperatively. In nine out of 12 patients CV RNA-positive before transplant HCV who were infection recurred. A PCR-HCV RNA assay was used as the diagnostic test (17). An interesting aspect in HCV recurrence was the variable expression of liver disease which ranged from normal liver histology to mild forms of chronic hepatitis. The activity of the hepatitis was always accompanied by an alteration of liver enzymes, and liver biopsies from eight of these patients showed the presence of HCV sequences, suggesting a correlation between viral replication and liver disease in these cases. togenic
Cotlclusioons Orthotopic liver transplantation for cirrhosis due to the HBV, HDV and HCV viruses is hampered by a high rate of reinfection and recurrence of hepatitis. However, there are different expressions of clinical hepatitis depending on the type of infection. HBV hepatitis presents the highest rate of reinfection compared to HDV and HCV infection. However, this negative rate will hopefully be reduced through using preparations of concentrated anti-HBs immunoglobulin or new antiviral drugs. Liver disease is always present in HBV recipients, while this is not the rule for patients reinfected by HDV. Reappearance of HCV infection is characterized by a variable spectrum of hepatitis which ranges from mild forms to typicai chronic hepatitis C.
References 6
1 Maddrey WC. Van Thiel DH. Liver transplantation: an overview. Hepatology 1988;8:948-9. 2 Belli I-, Dusheiko G, Rolles K, Burroughs AK. Liver transplantation for chronic viral hepatitis. Ital J Gastroenterol 1991; 23: 36-41. 3 Todo S. Demetris tranSphhtiOn
AJ, Van Thiei D, et ai. Orthotopic liver for patients with hepatitis B virus (HBV) related
liver diSeaSe. Hepatology 1991; 13: 619-26. 4 Bismuth H, Samuel D, Gugeneheim J, et al. Emergency liver UanSplatatiOn for fulminant hepatitis_ Ann Intern A&j 1987; 107: 337-41. 5 Emond JC. Aron PP, Whitington PF, Broelsch CE. Baker AL. Liver tWlSphta~OIl in the management of fulminant hepatic
failure. Gastroenterology 1989; 96: 1583-6. Rakela J, Lange SM, Ludwing J, Baldus WP. Fulminant hepatitis: Mayo Clinic experience with 34 cases. Mayo Clin Proc 1985: 60: 289-92. M, Zignego L. Samuel D, et al. Graft hepatitis delta
7 Reynes
virus reinfection after orthotopic liver transplantation iv HDv cirrhosis. Transplant Proc 1989; 21: 2424-S. 8 O’Grady J, Williams R. Liver transplantation for viral hepatitis. Br Med Bull 1990; 46: 481-91. 9 Samuel D, Bismuth A, Methieu D, et al. Passive immunoprophylaxis after liver transplantation in HBsAg positive patients. Lancet 1991; 337: 813-5. 10 Kaneko S, Miller RH, Di Bisceglie AM, et al. Detection of hepatitis B virus DNA in serum by polymerase chain reaction. Gastroenterology 1990; 99: 799-804.
TRANSPLANT
AND
MR. Stem.-.to* M, Banino F. et ai. A new Repatitis B virus strain in patients with severe anti-HBe positive chronic hepatitis B. .i Hepatol 1990: 10: 258-61. 12 Brunetto MR. Giarin MM, Oliveri F. et al. Willd-type and e antigen-minus hepatitis B viruses and course of chronic hepatitts. Proc Nati Acad Sci USA 1991; 88: 4186-90. 13 Mora N, Klintmalm GB, Poplawski S, et al. Recurrence of hepatitis B after liver transplantation: does hepatitis 5 immunoglobulin modify recurrent disease? Transplant Proc 1990: 22: 1549-50. 14 Muller R. Gubernatis 6. Farle MA. et al. Liver transplantation 11
Bruneito
in
sAGpositive
graft recipients prevention of recurrence by J Hepatoi I ‘\fl; II (Suppl. 2): S46.A. 15 Qttobrelli A, A, Smedile frr et al. Patterns of hepatiti; and disease in liver transplantation. Gast~oe~terology 1991; in press. 16 Bliveri P. Baldi M, Brunetto MR, et al. Antibody to hepatitis C virus in the serum of patients with chronic hepatitis. Em 9 epatol 1990; 2: 347-50. 17 Farci P, Alter HJ. Wang D, et al. A long-term study of hepatitis C virus replication in non-A, non-B hepatitis. N Engl J 1991: 325: 98-104.
s134
HEPAT 01073
Lives tram
atitis
lant for viral
ecurrence of reinfection A. Smedile’,
A. Marzano’, P. Farci*, E. Chiaberge’, F. Rosina’, M. Durazzo3, G. Verme
M. Abate’,
’ , F.
A. Ottobrelli’, M.R. izze tto3
‘Division of Gastroenterology, Molinette Hospital, Torino, Italy, ‘Laboratory of Infectious Diseases, Bethesda, United States of America and **hstituteof Intental Medicine, University of T&-in, Turin& kaly
transplantation has dramatically changed the life prospects of patients with terminal liver disorders. Progress in surgical methods and the use of potent antirejection treatment means that over 80% of those patients, whose life expectancy would otherwise have been very short, will now survive and be able to lead normal lives. Throughout the 1980s grafting has been progressively extended to now cover virtually all causes of liver damage (1). Patients with liver disorders of viral origin, however, are still exposed to the danger of graft reinfection: in those with type B hepatitis this risk and the ensuing risk of graft disease are so high that the decision to transplant in these cases has become controversial (2). The epidemiological problem is formidable, as batients with terminal viral cirrhosis or fulminant hepatitis are often young, i.e., they would normally be the best candidates for liver transplantation, and they account for the majority of cases requiring grafting in areas, such as the Mediterranean Basin, where viral hepatitis infections are hyperendemic. In recent years the problem of reinfection has led to interest in defining the virology of patients before grafting. This means that the risk of reinfection may be correlated with the various types of viral infection. It has also prompted a number of pretransplant prophylactic precautions and posttransplant treatment. This report summarizes how things stand at the beginning of the 1990s. The advent
of liver
Hepatitis B virus reinfection
In patients with hepatitis B the risk of reinfection is Correspondence:
very high; the source of reinfection is free virus in plasma or hidden in non-hepatic cells. Reinfection by the HBV is almost invariably accompanied by the recrudescence of hepatitis in the graft; the course of the recurrent disease often recapitulates the natural history of the original disease but may in some patients run an accelerated course to cirrhosis in a matter of a few months. While the medical sequelae of the infection can be mild and inapparent in the short term, within a few years from transplantation most of the HBV-reinfected patients experience serious liver dysfunction. In a series collected in Pittsburgh over the last decades, which accounts for the largest number of HBsAg carriers transplanted in the world, the complications related directly or indirectly to HBV reinfection have significantly reduced the life expectancy of the transplanted carriers compared to those candidates protected from HBV by the presence of spontaneous anti-HBs (3). Detailed analysis of the reinfection risk has shown that this depends above all on three factors: (i) the clinical type of HBV disease leading to transplantation; (ii) the original type of HBV infection; and (iii) whether or not the patient was given specific prophylaxis before grafting. Hi3V
presentation
Liver transplantation has been performed in patients with end-stage post-hepatitis B cirrhosis and fulminant hepatitis (FH). The latter has been considered an absolute condition for liver transplant because the immediate prognosis is very poor. The results achieved with FH have produced l-year survival rates of 5670% in many series published in Europe and North America (4,5). In
AmoninaSmedile.M.D., Division of Gastroenterology, Ospedale Molinette, C.so Bramante 88, 10126 Torino, Italy.
GIVER TRANSPLANT
AND REINFE~IQN
the previous series, when t aged medically, the s ival rate was less than 10% (6). Most of the cases acute liver failure had a viral a predominant infection by etiology patitis worldwide. and NA Vast surgical experience has been gained in Pittsburgh, North America and Villejuif, France. In Pittsburgh it was at patients transplanted for chronic sAgpositive lives disease showed a high risk U; reinfection, is incidence was relatively low for patients who underwent liver transplant for fulminant liver failure. Indeed out of eight patients who underwent emergency only one died. The remaining patients are QLT for alive and ;e not been reinfected 20 months after the operation. A similar experience was r in a series of 21 liver transplants for V). The rate of reinfe l/4 in patients with finding may be related to the massive necrosis of infected hepatocytes and early elimination of viremia which is characteristic of FH. During the fulminant course, serological markers of I-I V infection are usually not found. By contrast, patients with chronic HBV infection and stable viremia have a higher risk of reinfection. possible that in this chronic status of infection DNA sequences, in addition to being liver, are also harbored in extrahepatic tissues such as mononuclear blood cells and reactivated later on (7). Pretransplant virological status
The subtype of chronic I-IBV hepatitis in the recipients is a major factor influencing the rate of reinfection. Overall it has been observed that in patients analyzed before liver transplant those with chronic anti-HBe-positive hepatitis had a lower incidence of reinfection compared to those with HBeAg-positive hepatitis (8). Although liver transplant in patients with HBsAg-positive cirrhosis has been performed since the initial years of liver grafting, at the beginning patients were not divided according to their replicative status as detected by molecular hybridization assay (HBV DNA positive or HBV DNA negative) which is considered a more reliable diagnostic test than testing for the hepatitis B e antigen/antibody system. In a recent study conducted at Villejuif, patients were revaluated according to HBV replication. Patients who were HBV DNA positive had a much greater risk of HBsAg recurrence than patients who were HBV DNA negative (96% vs. 29%) (9). In our series of seven patients transplanted for HBV cirrhosis, six out of seven were reinfected within 2 years. Recurrence of liver disease in the graft was the rule with episodes of acute hepatitis leading to chronic hepatitis and cirrhosis. The
8135
antibody since even in there are subliminal levels o are revealed using sensitive assays such as cation methods (10). Thus, the pre-0I.T status is not relevant in predicting the recurren
virologic aspects which could be relevant in the recurrence of disease. Non-tral~splanted patients affected by this subtype of chronic hepatitis often show a point mutation at the 1894 nucleotide site which renders the core g synthesize the ‘e’ protein by producing a This mutation generates a mutant po virions that can be selected during the The predominance of this mutant, for reasons that are as yet unclear. can be selected in the reinfection of the new graft by reproducing the typical V infection or a more rapid and severe chronic hepatitis. It is possible t termine the ratio between these two populations of virions by using an oligonucleotide assay. In five cases studied we showed that the wild-type prevailed in two eAg-minus mutant in two other cases and cases, the a mixture of both was present in the remaining patient. An extensive analysis of transplanted patients is necessary before any conclusions may be drawn. In one patient who underwent liver transplant for cirrhosis B a complete characterization by the sequencing of amplified DNA has recently been reported (12). Prevention of HBV by immunoprophylaxis
The risk of reinfection has stimulated the use of a number of preventive measures, such as pretreatment of liver recipients with antivirals, HBV vacciuatton and passive prophylaxis with immunoglobulins against HBV (13). However, neither the antivirals nor vaccination have proved effective. The administration of HBIg over the short term was likewise disappointing, but promising results have recently been reported with protocols providing this prophylaxis over a long period (14). The experience of the Hannover group in Germany and of the Villejuif group in France indicates that substitution therapy with 10 000 IV/l of HBIg during the anhepatic phase plus 10 000 additional units for the next 6 to 8 days followed by periodical mainteuance doses to maintain the titre of anti-HBs over 100 UIA, is effective in preventing recurrence in patients who test negative prior to
A. SMEDILE et al.
S136 grafting for HBV-DNA by ordinary hybridization assays. Unfortunately, this prophylaxis is not effective in HBVDNA-positive patients, for whom no effective form of prevention has yet been devised. HDV reinfection Hepatitis type D also presents a high risk of reinfection with a variable expression of liver disease recurrence. The reinfection rate after OLT for cirrhosis due to HDV has been reported to be in the range of 77% and 86% in two series from Italy-Belgium and France (1215). Recurrence of liver disease varied between 52-28% in the two series. The pattern of HDV reinfection was peculiar in this setting, opening up new insights into the pathogenesis of HDV infection. The transplant model revealed that HDV infection is precocious, sometimes only a few days after transplant. The virus is to be found in the hepatocytes where it remains for months and hepatitis devetops only when there is a full expression of HBV markers. This suggests that the helper virus plays an important role in the recurrence of hepatitis. In our series of 31 patients transplanted for HDV cirrhosis there are five patients who have not yet been reinfected after 8 months to 2 years of follow-up as diagnosed by hybridization assays. The technique of PCR for HDV RNA has recently revealed two additional cases showing a subliminal replication, without signs of hepatitis. The recurrence of hepatitis in the allograft was similar to HDV infection in non-transplanted patients, with a rapid progression to chronic hepatitis and cirrhosis in a shorter period of time (6 months to 1 year). What role HBV plays in the rapid progression of liver disease is still unknown.
HCV reinfection Liver transplants have been performed in many patients who have been classified as having NANB or cryp-
cirrhosis. In these cases diagnostic assays for the hepatitis C virus (HCV) were carried out in retrospect in order to determine the prevalence of this infection in pretransplant sera and to study the recurrence of HCV infection and disease. In our series of 27 cases we found a high percentage of HCV infection in cryptogenic cirrhosis (82%), which is a percentage that is similar to those reported in many epidemiological studies (16). The rate of reinfection correlated well with the presence of HCV RNA preoperatively. In nine out of 12 patients CV RNA-positive before transplant HCV who were infection recurred. A PCR-HCV RNA assay was used as the diagnostic test (17). An interesting aspect in HCV recurrence was the variable expression of liver disease which ranged from normal liver histology to mild forms of chronic hepatitis. The activity of the hepatitis was always accompanied by an alteration of liver enzymes, and liver biopsies from eight of these patients showed the presence of HCV sequences, suggesting a correlation between viral replication and liver disease in these cases. togenic
Cotlclusioons Orthotopic liver transplantation for cirrhosis due to the HBV, HDV and HCV viruses is hampered by a high rate of reinfection and recurrence of hepatitis. However, there are different expressions of clinical hepatitis depending on the type of infection. HBV hepatitis presents the highest rate of reinfection compared to HDV and HCV infection. However, this negative rate will hopefully be reduced through using preparations of concentrated anti-HBs immunoglobulin or new antiviral drugs. Liver disease is always present in HBV recipients, while this is not the rule for patients reinfected by HDV. Reappearance of HCV infection is characterized by a variable spectrum of hepatitis which ranges from mild forms to typicai chronic hepatitis C.
References 6
1 Maddrey WC. Van Thiel DH. Liver transplantation: an overview. Hepatology 1988;8:948-9. 2 Belli I-, Dusheiko G, Rolles K, Burroughs AK. Liver transplantation for chronic viral hepatitis. Ital J Gastroenterol 1991; 23: 36-41. 3 Todo S. Demetris tranSphhtiOn
AJ, Van Thiei D, et ai. Orthotopic liver for patients with hepatitis B virus (HBV) related
liver diSeaSe. Hepatology 1991; 13: 619-26. 4 Bismuth H, Samuel D, Gugeneheim J, et al. Emergency liver UanSplatatiOn for fulminant hepatitis_ Ann Intern A&j 1987; 107: 337-41. 5 Emond JC. Aron PP, Whitington PF, Broelsch CE. Baker AL. Liver tWlSphta~OIl in the management of fulminant hepatic
failure. Gastroenterology 1989; 96: 1583-6. Rakela J, Lange SM, Ludwing J, Baldus WP. Fulminant hepatitis: Mayo Clinic experience with 34 cases. Mayo Clin Proc 1985: 60: 289-92. M, Zignego L. Samuel D, et al. Graft hepatitis delta
7 Reynes
virus reinfection after orthotopic liver transplantation iv HDv cirrhosis. Transplant Proc 1989; 21: 2424-S. 8 O’Grady J, Williams R. Liver transplantation for viral hepatitis. Br Med Bull 1990; 46: 481-91. 9 Samuel D, Bismuth A, Methieu D, et al. Passive immunoprophylaxis after liver transplantation in HBsAg positive patients. Lancet 1991; 337: 813-5. 10 Kaneko S, Miller RH, Di Bisceglie AM, et al. Detection of hepatitis B virus DNA in serum by polymerase chain reaction. Gastroenterology 1990; 99: 799-804.
TRANSPLANT
AND
MR. Stem.-.to* M, Banino F. et ai. A new Repatitis B virus strain in patients with severe anti-HBe positive chronic hepatitis B. .i Hepatol 1990: 10: 258-61. 12 Brunetto MR. Giarin MM, Oliveri F. et al. Willd-type and e antigen-minus hepatitis B viruses and course of chronic hepatitts. Proc Nati Acad Sci USA 1991; 88: 4186-90. 13 Mora N, Klintmalm GB, Poplawski S, et al. Recurrence of hepatitis B after liver transplantation: does hepatitis 5 immunoglobulin modify recurrent disease? Transplant Proc 1990: 22: 1549-50. 14 Muller R. Gubernatis 6. Farle MA. et al. Liver transplantation 11
Bruneito
in
sAGpositive
graft recipients prevention of recurrence by J Hepatoi I ‘\fl; II (Suppl. 2): S46.A. 15 Qttobrelli A, A, Smedile frr et al. Patterns of hepatiti; and disease in liver transplantation. Gast~oe~terology 1991; in press. 16 Bliveri P. Baldi M, Brunetto MR, et al. Antibody to hepatitis C virus in the serum of patients with chronic hepatitis. Em 9 epatol 1990; 2: 347-50. 17 Farci P, Alter HJ. Wang D, et al. A long-term study of hepatitis C virus replication in non-A, non-B hepatitis. N Engl J 1991: 325: 98-104.