Occurrence of non-A, non-B post-transfusion hepatitis in heart surgery. Prospective study on the value of the determination of serum alanine aminotransferase and detection of anti-HBc antibodies in blood donors

We studied a group of 64 patients undergoing cardiac surgery for the occurrence of post-transfusion hepatitis during a follow-up period of 5 months. They received blood units (packed red cells in saline-adenine-glucose medium and/or fresh frozen plasma exclusively) from 447 volunteer donors. Post-transfusion hepatitis was identified in 5 patients: 1 patient had cytomegalovirus hepatitis and the remaining 4 cases were defined, by exclusion, as non-A, non-B hepatitis (with prevalence and incidence rates of 80% and 6.25% respectively). We found no statistically significant differences between the numbers of transfused blood product units in patients who developed non-A, non-B hepatitis as compared to those who did not. Our analysis of the predictive effectiveness of alanine aminotransferase and anti-HBc antibodies screening in blood donors to prevent non-A, non-B post-transfusion hepatitis led to the following conclusions: we failed to confirm the association between anti-HBc in blood donors and enhanced risk of non-A, non-B hepatitis in recipients since no case developed among patients receiving blood products from anti-HBc positive donors. So, 20 donors (4.5%) would have been discarded without any reduction of the incidence of non-A, non-B hepatitis. we could not confirm nor exclude the possibility that screening donor blood for elevated alanine aminotransferase levels would have reduced the number of non-A, non-B hepatitis in recipients.     

A cDNA fragment of hepatitis C virus isolated from an implicated donor of post-transfusion non-A, non-B hepatitis in Japan.

Recently, a cDNA from the hepatitis C virus (HCV) RNA genome has been isolated in the USA from a chronically infected chimpanzee. In order to isolate HCV cDNA derived from human material, RNA was extracted from plasma of a Japanese blood donor implicated in post-transfusion non-A, non-B hepatitis and HCV cDNA was synthesized and amplified by the PCR method using HCV-specific oligonucleotide primers. The cDNA fragment, 583 nucleotides long, showed 79.8% homology at the nucleotide level and 92.2% homology at the amino acid level compared with the prototype HCV cDNA. These results provides further evidence to show that HCV is closely associated with the development of post transfusion non-A, non-B hepatitis.     

Blood transfusion and hepatitis: still a threat?

The incidence of post-transfusion hepatitis (PTH) in recipients of blood products is reviewed. PTH was observed in 10%-12% of recipients of blood products in the United States, 2%-4% in northern Europe and 15%-20% in southern Europe. All studies indicate that 80%-90% of all PTH cases are attributed to non-A/non-B. At least 40% of the patients with PTH non-A/non-B will develop chronic hepatitis or cirrhosis. No specific tests for the detection of the non-A/non-B agent(s) exist. However, several independent studies indicate that part of the donors carrying the infectious non-A/non-B agent have increased levels of alanine amino transferase (ALT). When donors are excluded with elevated ALT values, it is estimated that about 30% of the PTH non-A/non-B cases would be prevented. Some studies indicate that anti-hepatitis B core (anti-HBc) positive donors may carry an increased risk to transmit the non-A/non-B agent, but more recent studies do not confirm this. There is hope that a specific non-A/non-B test will be developed soon.     

Transmission of non-A, non-B hepatitis agent to chimpanzees from patients of epidemic hepatitis

Two chimpanzees were inoculated intravenously with acute-phase sera obtained from two patients with epidemic hepatitis. They developed histopathologically confirmed hepatitis. Electron microscopic examination of the liver showed peculiar cytoplasmic tubular structures in the hepatocytes. These ultrastructural findings were similar to those described for the livers of chimpanzees inoculated with the F strain of non-A, non-B hepatitis agent derived from a posttransfusion hepatitis case. The chimpanzee that had recovered from hepatitis caused by the F strain of non-A, non-B hepatitis agent was re-challenged with the serum from one of the patients. The chimpanzee developed neither clinical signs nor histological changes of hepatitis. These results suggested that non-A, non-B hepatitis agent was involved not only in post-transfusion hepatitis but also in epidemic hepatitis.     

Seroepidemiology of hepatitis C virus in Beijing, China

To investigate the seroprevalence of hepatitis C virus (HCV) in China we tested sera from healthy individuals without hepatitis and no history of parenteral blood exposure and from patients admitted to a hepatitis hospital in Beijing. Sera were tested for anti-HCV by first-generation enzyme immunoassay; selected positives were tested with two second-generation EIAs, one utilizing recombinant antigens and the other synthetic peptides. We found anti-HCV with the following frequencies: 10 of 164 (6%) individuals with no disease; 2 of 36 (5.5%) patients with acute non-A non-B hepatitis (NANBH); 26 of 39 (67%) patients with post-transfusion NANBH; 10 of 34 (29%) patients with chronic hepatitis negative for hepatitis B surface antigen (HBsAg); 3 of 30 (10%) patients with chronic HBsAg-positive hepatitis; 0 of 19 patients with acute HBsAg-positive hepatitis. Of 24 repeat-positive sera, 19 were positive by both and 4 by one second-generation tests. We conclude that hepatitis C infection is common in China, that it contributes substantially to the incidence of post-transfusion hepatitis, and that HCV plays a significant role in both acute and chronic hepatitis. Further studies are needed to extend these observations and to define the predominant routes of transmission of HCV in China.     

Randomised controlled trial of interferon alfa (lymphoblastoid interferon) in chronic non-A non-B hepatitis.

OBJECTIVE--To determine the effect of low dose interferon alfa (human lymphoblastoid interferon) on aminotransferase activities in chronic non-A non-B hepatitis. DESIGN--Prospective randomised controlled parallel group study of active treatment versus no treatment carried out over 16 weeks and preceded by baseline measurements at weeks 8 and 4 and time zero. SETTING--HEPATOLOGY outpatient clinics in secondary referral centres. PATIENTS--Fourteen adults with histologically proved chronic hepatitis and persistently raised aminotransferase activities for six months or more. INTERVENTIONS--Seven patients randomised to receive interferon alfa 5 megaunits (MU) daily for one week, reducing to 5 MU thrice weekly for seven weeks, then 3 MU thrice weekly for eight weeks. Controls not treated. END POINT--Control of hepatic enzyme activity in chronic non-A non-B hepatitis. MEASUREMENTS AND MAIN RESULTS--Serum aspartate aminotransferase activity remained raised in controls (mean increase in study period 23.4 U/l) but fell rapidly to normal in the treated group (mean decrease 106.4 U/l). In four cases values were normal by eight weeks and in five cases by 16 weeks. Only minor side effects were recorded (fever, myalgia), which became less common as treatment progressed. CONCLUSIONS--Continuous low dose interferon alfa reduces aspartate aminotransferase activity to normal in most patients with chronic non-A non-B hepatitis and may prevent progression to cirrhosis.     

Study of serological and biological markers in viral hepatitis. 157 hemophiliacs

We observed for a two years period 157 hemophiliacs (138 with hemophilia A whose 13 were severe and 19 with hemophilia B whose 13 were severe) and we studied the incidence of liver dysfunction and the role played by HB and non-A, non-B, viruses. Whereas 32 patients not related had no evidence of serological HB virus markers (by radioimmunoassay), 88 (70,4 %) among the 135 hemophiliacs with large or small exposure to blood products were "HB positive". 90,9 % were positive for anti-HBs and anti-HBc antibodies and only two patients had persistent antigenemia. These results appeared independent of the kind of treatment (factor VIII or factor IX concentrates). Six among 17 children born since 1974, when the antigen was detected by RIA, had the serological HB virus markers, showing that this method is not sufficient to completely eliminate the HB virus. However the amount of viruses injected is too small to induce an acute hepatitis and rather produces specific antibodies which protect hemophiliacs against reinfection. An elevated level of serum transaminases (SGPT) was observed in 9,4 % of non treated hemophiliacs, 15,1 % of treated hemophiliacs with no serological markers of HB virus and 27,7 % of treated hemophiliacs "HB positive". This shows that the use of concentrates and the occurring of HB virus in the patients are not the only factors producing liver dysfunction. The role of non-A, non-B viruses has been recognized in 7 patients out of 9 with transient elevation of serum transaminase levels, by Trepo with an immunodiffusion technique.     

Hepatitis safety of a new prothrombin complex preparation, sterilized according to the method of LoGrippo. Results of a prospective clinical trial

In a controlled, prospective clinical trial with almost 300 patients undergoing cardiovascular surgery, the hepatitis risk was examined of a new prothrombin complex (PPSB) preparation produced from pooled plasma, which was cold sterilized according to the method of LoGrippo with beta-propiolactone and UV-light. Of 268 evaluable patients, 102 belonged to a group receiving PPSB and 166 belonged to a control group without PPSB. 25 batches of PPSB in dosages of up to 4,500 units per patient, in total, were used. The mean requirement for transfusion of blood or plasma was 10 units per patient in the group receiving PPSB and slightly more than 2 units per patient in the control group. In both of the groups, 3 hepatitis infections occurred (5 cases of non-A, non-B, 1 case of type B), corresponding to hepatitis incidences of 2.9 and 1.8%, respectively. The difference in hepatitis incidence between both groups was statistically not significant. This demonstrates, on the one hand, the hepatitis safety of the sterilized PPSB and, on the other, that multiple transfusion is no longer associated with a high risk of hepatitis when the guidelines of modern donor screening are followed.     

Isolation of the novel agent from human stool samples that is associated with sporadic non-A, non-B hepatitis.

The agent(s) responsible for sporadic non-A, non-B hepatitis in humans was serially transmitted in rhesus monkeys by intravenous inoculation of the stool extract from a patient. A novel agent called HFV (hepatitis French [origin] virus) was present as 27- to 37-nm particles in the infectious stool extract. Hepatopathic lesions were noticed in infected monkeys during the acute phase of illness. The purified viral 27- to 37-nm particles consist of a double-stranded DNA of approximately 20 kb and are detected in infected monkey liver. Analysis of cell culture detects the approximately 20-kb-long viral DNA in stool samples from infected monkeys and sporadic enteric non-A, non-B hepatitis patients. Furthermore, the 27- to 37-nm viral particles were able to protect monkeys challenged with infectious stool extract. Our results indicate that 27- to 37-nm virus like particles are responsible for sporadic non-A, non-B hepatitis in rhesus monkeys.     

Blood Transfusion: Use and Abuse of Blood Components

Transfusion of whole blood and some blood components may result in serious or fatal complications, among which hepatitis is most frequent (20,000 to 30,000 cases and 3,000 deaths a year). Although hepatitis B virus (HB Ag) sometimes is implicated in posttransfusion hepatitis, non-A non-B. virus(es) (hepatitis “C” virus) probably accounts for most posttransfusion hepatitis.Half of all blood transfusions may be unnecessary.Responsible transfusion practice requires use of appropriate blood components for which there is adequate justification. Transfusion of red blood cells should be given as packed cells in most instances and whole blood should seldom be used.     

A structural protein of hepatitis C virus expressed in E. coli facilitates accurate detection of hepatitis C virus.

A putative core protein derived from hepatitis C virus was expressed in E. coli. More than 5% of the total protein expressed in the bacteria after induction by isopropylthio-beta-D-galactoside was shown to be the expected protein. Western blotting with this E. coli lysate proved to be more efficient than ELISA with a non-structural viral protein, C100, to detect infection of hepatitis C virus in the sera of patients with non-A, non-B chronic hepatitis, hepatocellular carcinoma as well as in sera from healthy persons.     

Prevalence of hepatitis C virus antibody among healthy blood donors and non-A, non-B hepatitis patients in Thailand

With the antigen expressed in yeast from a cDNA clone encoding a non-structural region of newly discovered hepatitic C virus (HCV) genome, the prevalence of HCV antibody in people in Thailand was investigated. Antibody was detected in 2.6% of healthy blood donors and in 2.8% of healthy pregnant women. These prevalence rates were higher than those reported previously from Japan, USA and European countries. Among community-acquired, sporadic cases of acute and chronic non-A, non-B hepatitis, however, only 5.7% and 15.4% were shown to possess the antibody, respectively. Among hepatocellular carcinoma patients who were negative for hepatitis B surface antigen in the sera, 11.1% had antibody to HCV. These seroepidemiological data suggest that HCV plays an important role as an etiological agent in Thailand; however, other agents must also be involved in etiologic agents of viral hepatitis and chronic liver disease.     

Hepatitis non-A,non-B.

Evidence for the existence of hepatitis non-A, non-B includes epidemiologic data and results of transmission studies indicating the presence of hepatitis that could not be explained by known causative agents. The diagnosis is suggested in patients who have multiple episodes of acute hepatitis or who contract hepatitis after transfusion, hemodialysis or drug abuse. Sporadic cases are common. Three such cases are described to illustrate that the disease is clinically indistinguishable from hepatitis A or B. The diagnosis is based on the absence of serologic markers of hepatitis A and B and of infection by Epstein-Barr virus and cytomegalovirus, or on serologic evidence of previous infection with hepatitis A and B.     

Incidence of hepatitis non-A,non-B compared with types A and B in hospital patients.

To establish the relative frequencies of types A, B and non-A, non-B hepatitis, stored samples of blood from all the cases of acute viral hepatitis seen over a period of 9 years in a general hospital for adults were classified according to their type by presently available serologic methods. The study included 456 episodes of hepatitis in 447 patients, distributed as follows: 114 episodes of hepatitis A (25%), 282 of hepatitis B (62%) and 60 of hepatitis non-A, non-B (13%). The episodes of non-A, non-B hepatitis were equally distributed between the sexes, suggesting a mode of transmission different from that of hepatitis A or B, which had male/female ratios of 2.4 and 3.1 respectively. The low proportion of hepatitis non-A, non-B may not reflect its real frequency, since it often escapes clinical recognition.     

Effect of concurrent acute infection with hepatitis C virus on acute hepatitis B virus infection.

OBJECTIVE--To investigate the possible interference with acute hepatitis B virus infection by co-infection with hepatitis C virus. DESIGN--Analysis of stored sera collected for transfusion transmitted viruses study in 1970s. SETTING--Four major medical centres in the United States. PATIENTS--12 recipients of blood infected with hepatitis B virus. MAIN OUTCOME MEASURES--In 1970s, presence of antibodies in hepatitis B virus and raised serum alanine aminotransferase concentration; detection of antibodies to hepatitis C virus with new enzyme linked immunoassays. RESULTS--Five of the 12 patients were coinfected with hepatitis C virus. Hepatitis B surface antigen was first detected at day 59 in patients infected with hepatitis B virus alone and at day 97 in those coinfected with hepatitis C virus (p = 0.01); median durations of antigenaemia were 83 and 21 days respectively (p = 0.05), and the antigen concentration was lower in the coinfected patients. Alanine aminotransferase patterns were uniphasic when hepatitis B virus infection occurred alone (range 479-2465 IU/l) and biphasic in patients with combined acute infection (no value > 380 IU/l; p = 0.0025). Four coinfected recipients developed chronic hepatitis C virus infection. The fifth patient was followed for only four months. CONCLUSIONS--Acute coinfection with hepatitis C virus and hepatitis B virus inhibits hepatitis B virus infection in humans, and onset of hepatitis B may reduce the severity of hepatitis C virus infection but not frequency of chronicity. Alanine aminotransferase concentration showed a biphasic pattern in dual infection.     

Prevalence of antibodies to hepatitis C virus (HCV) in haemophiliacs

The prevalence of 1) hepatitis C virus (HCV), an agent likely to be responsible for parenterally transmitted hepatitis non-A, non-B, 2) hepatitis B virus (HBV) and 3) human immunodeficiency virus (HIV) infection was studied in 211 patients with clotting disorders (78% of the patients had residual factor activities of less than or equal to 2%). Of these patients 71% were positive for HBV markers and 44% for HIV markers. Using a new ELISA technique, 80% were anti-HCV-positive. The prevalence of anti-HCV was greater in patients with more severe clotting disorders and was related to the total amount of replacement therapy received; the prevalence was less in older patients. Seroconversion after a single exposure to dry heat-treated factor concentrates was documented in 3 patients 3-4 months after exposure.     

The natural course of chronic hepatitis C

Abstract: In 1988, investigators from the Chiron Company (USA) detected the non-A, non-B agent and named it hepatitis C virus (HCV). An anti-HCV antibody assay (ELISA) and subsequently confirmation tests (immunoblot and polymerase chain reaction) were developed. HCV exposure results in a chronic infection in a majority of cases. This chronic infection is associated with slowly progressive chronic liver disease. Chronic HCV infection is, like HBV, also associated with the development of hepatocellular carcinoma. Most HCV carriers are infected by parenteral routes. Intravenous drug users have the highest risk of becoming infected. Intrafamiliar spread is seen in certain parts of the world but sexual and perinatal transmission does not play an important role in spreading the infection. Antiviral therapy (alpha-interferon) in patients with chronic hepatitis C will normalize liver function tests in about 25% of the cases.     

Association of human hepatocellular membrane fusions with non-A, non-B hepatitis

Liver biopsies from patients with alcoholic hepatitis, chemical hepatitis, or viral hepatitis types A, B, or non-A, non-B were examined by electron microscopy. Circular, fused, cytoplasmic membranes were observed in hepatocytes of 17% of patients with hepatitis type B and 92% of patients with hepatitis type non-A, non-B. The membrane alterations were not observed in hepatocytes of patients with the other types of hepatitis. The greater frequency of altered cytoplasmic membranes in hepatocytes of patients with non-A, non-B hepatitis was shown to be statistically significant (p less than 0.05) when compared to that in patients with viral hepatitis type B.     

Hepatitis B Virus Infection—Current Concepts of Chronicity and Immunity

Among the three types of viral hepatitis agents—A, B and non-A, non-B—the hepatitis B virus (HBV) has been best characterized by immunologic and recombinant DNA technologies. The indefinite persistence of hepatitis B virus infection in 85% to 90% of perinatally infected infants and in about 10% of those infected later in life accounts for a worldwide epidemiologic reservoir of more than 200 million carriers who are at a high risk for the development of δ-infection, chronic liver disease and hepatocellular carcinoma. Active immunization with a safe and effective vaccine, derived from the plasma of carriers of hepatitis B surface antigen (HBsAg), is envisaged to avoid viral hepatitis type B and its chronic sequelae. In addition to serologic and immunohistochemical markers of hepatitis B virus infection, hybridization assays using cloned HBV DNA have provided new insight into the biology of this virus, its persistence and its oncogenic potential in humans and in animal models. Genetic similarities have been recognized between HBV and the antigenically distinct non-A, non-B agents implicated in some cases of transfusion-associated chronic hepatitis. Structurally this unique group of HBV and HBV-like agents are DNA viruses with functional attributes of integration and replication analogous to the retroviruses.