Medical Research Council Working Party. Post-transfusion hepatitis in a London hospital: results of a two-year prospective study

Prevalence and consistency of ALT elevation in plasmapheresis donors: implications for the assessment of blood product infectivity

Alanine aminotransferase (ALT) levels were determined in 8,420 plasmapheresis donations obtained from 431 donors over a period of 18 months. Using sex-differentiated normal ranges 2.5% of donations but 23% of donors exhibited elevated ALT levels on at least 1 occasion. Amongst the donors with elevated ALT this was only seen on 1 occasion in one third, while a quarter had elevations in consecutive donations. No donors with consecutive elevations above 100 IU/l were detected. The results are discussed in terms of the guidelines currently recommended for assessing post-transfusion hepatitis infectivity of blood products, such as factor VIII. It is concluded that the current allowance for infection acquired from sources other than blood products under consideration may be over-generous, leading to a potential underestimate of the true rate of infection.

New developments in cytomegalovirus prevention and management

The use of CMVIG, approved in 1990 for prophylactic administration in seronegative recipients of kidneys from seropositive donors, has been shown to be extremely effective in preventing the considerable morbidity and mortality associated with CMV disease. While the complex interactions between CMV and the immune system, including the effects of immunosuppressive therapy, are still under investigation, passive immunization with CMVIG offers a practical, safe, and cost-effective means of clinical intervention in renal transplant patients known to be at risk for CMV disease. Further clinical studies will need to explore the mechanisms of interaction of CMVIG with reactivation of latent infection and superinfection and with allograft dysfunction and antirejection therapy. Studies that evaluate the use of CMVIG in combination with other pharmacologic and immunologic interventions, both for prevention and treatment of CMV disease, will guide the use of the drug. CMVIG promises to be most helpful in reducing morbidity and mortality in transplant recipients and other particularly at-risk populations such as those who are immunosuppressed iatrogenically.

Low incidence of non-A, non-B post-transfusion hepatitis in London confirmed by hepatitis C virus serology

To see whether the introduction of screening tests for post-transfusion non-A, non-B hepatitis (NANBH) in the UK would be worth while, the incidence of such hepatitis was assessed among patients receiving blood during operations at five hospitals served by the North London Blood Transfusion Centre. 387 patients, who each received blood or blood components from an average of 3 donors were followed up prospectively and blood samples were taken every 2 weeks for 3 months and then each month for a further 3 months. 229 patients also provided a sample at 12 months. All available patient and donor samples were tested for alanine aminotransferase concentrations and for antibody to hepatitis C virus (anti-HCV) by ELISA. Repeatedly anti-HCV positive samples were submitted to supplementary HCV assays. 1 of the 387 patients showed biochemical evidence of acute post-transfusion NANBH after exclusion of non-viral causes. Anti-HCV developed in this patient and the seroconversion was confirmed by recombinant immunoblot assay and polymerase chain reaction. Serum from 1 of the 8 donors whose blood he received was positive for anti-HCV by all three methods. In another patient HCV seroconversion was shown by ELISA but alanine aminotransferase concentrations remained normal throughout follow-up. His samples and those of his 2 donors were negative for HCV by the polymerase chain reaction. A third patient showed rises in alanine aminotransferase compatible with post-transfusion NANBH, but serology and polymerase chain reaction assays for HCV were negative for her samples and those of her donors. Anti-HCV reactivity likely to be false positive (negative by both confirmatory tests and no adverse effects in recipients) was seen in 6 of 1283 donors. This study, despite its being carried out in the part of the UK with the highest frequency of infectious markers in blood donations, has shown a very low incidence of post-transfusion NANBH.

Chronic liver disease. A case control study of the effect of previous blood transfusion

A means of assessing hepatitis NANB virus infection, via blood transfusion, as a cause of chronic liver disease was investigated in a hospital in each of two cities in England. Patients with chronic liver disease were matched for age and sex with other patients in the same hospital and histories taken included details of previous operations and blood transfusions; if these were within ten years of the study enquiries were made of hospital records officers. All positive histories were found correct, but about one third of previous transfusions had been omitted by both case and control patients. Sixty-seven male and 35 female patients with chronic liver disease and their controls were included in analyses. The only clear difference which emerged related to residence for more than a year in the Middle or Far East by male case- (40%) or control- (21%) patients (P less than 0.05). The exclusion of patients with this history left only 34 pairs in which five (15%) of the case patients and one (3%) of the control patients had a transfusion history: this difference was not statistically significant. Although the study results have shown no clear evidence of blood transfusion as a major cause of chronic liver disease in Britain, the study method, with sufficient numbers to allow analyses of newly diagnosed patients with confirmed transfusion histories, could be used to provide an ongoing assessment of the risk.

Homologous blood use and conservation techniques for cardiac surgery in the United Kingdom

The transfusion laboratories of 32 cardiothoracic surgical centres for adults were surveyed to determine the donor blood requirement for open heart surgery in the United Kingdom. Details of the transfusion practice and the use of blood conservation techniques were sought from a representative senior cardiac anaesthetist at each centre. Suitable data were received from 24 transfusion laboratories (75%) and 29 anaesthetists (90%). The mean (SD) blood use was 5.07 (1.53) units per operation. Seven centres routinely transfused fresh frozen plasma to all patients postoperatively. Experience with autologous deposit (three centres), "cell separators" (four centres), and the reinfusion of shed mediastinal blood (four centres) was limited. Prebypass phlebotomy for postbypass reinfusion (14 centres) and the infusion of residual oxygenator blood (27 centres) were the conservation techniques most commonly applied. In only nine centres was a postoperative normovolaemic anaemia to a haemoglobin concentration of less than 100 g/l accepted. Applying blood conservation techniques more widely would help to maintain blood supplies and reduce morbidity and mortality related to transfusion.

Posttransfusion hepatitis in Toronto, Canada

Five hundred seventy-six consecutive patients from the surgical, obstetrical, and medical services who had received transfusions of volunteer blood were followed-up at regular intervals for 6 mo. Fifty-three (9.2%) developed acute posttransfusion non A, non B hepatitis. Forty-seven (89%) had an incubation period between 2 and 8 wk. The frequency was not related to the age or sex of the patient, the indications for transfusion, the type of surgery, anesthesia, the presence of perioperative hypotension, or the number of units of blood transfused. There were no cases of fulminant hepatitis. Nineteen of the 53 patients (36%) with acute posttransfusion hepatitis progressed to chronic hepatitis. Development of chronic hepatitis was not related to the age or sex of the patient, the incubation period of the preceding acute hepatitis, the presence of shock or malignancy, or the number of units of blood transfused. Patients with higher levels of alanine aminotransferase during the acute hepatitis were more prone to develop chronic hepatitis. The finding of 9.2% of transfusion-related hepatitis in recipients of hepatitis B surface antigen-screened blood from volunteer donors underscores the potential sequelae of blood transfusion, especially as a source of contribution to the pool of chronic liver disease.

Post-transfusion non-A, non-B hepatitis: significance of raised ALT and anti-HBc in blood donors

The FDA has recommended that all blood collected in the USA should be screened for antibody to hepatitis B core antigen (anti-HBc) and for raised alanine aminotransferase (ALT) as possible indicators of non-A, non-B hepatitis carriage. As part of an assessment of the medical and economic implications of such a screening programme, we have screened 1,742 regular blood donors for ALT and 2,086 (including the same 1,742) for anti-HBc. 42 (2.4%) of the 1,742 donors had ALT levels above 45 units/l. Clinical assessment of 33 of these revealed that 26 exceeded their ideal body weight by more than 10% and 15 by more than 20%. 11 admitted to an alcohol intake of over 40 g daily. In all, 82% of donors with raised ALT had a 'non-viral' clinical explanation for this abnormality. Anti-HBc was detected in 42 (2.0%) of the 2,086 donors screened. 27 (64%) also had anti-HBs, and 11 (26%) had anti-HBe. There was no overlap between donors with raised ALT and those with anti-HBc. Combined screening would lead to a loss of at least 4.4% of donations in the population studied. In view of the medical and economic implications of the introduction of these screening tests, and the poverty of data on the clinical significance of post-transfusion non-A, non-B hepatitis, we conclude that such a screening programme cannot be justified at present. Further studies are required, including a prospective controlled trial of the effects of screening.

Transfusion-transmitted cytomegalovirus infections: significance and control

Cytomegalovirus (CMV) is a herpes virus which can give rise to primary infections, reactivated infections, or reinfections in humans. Seroepidemiologic studies have shown CMV infection to be worldwide with the highest antibody prevalences detected in Third World countries; however, significant regional variations can be seen within a given country. Antibody prevalence varies directly with age and inversely according to socioeconomic status. Numerous prospective studies of blood transfusion recipients carried out since 1966 have shown marked differences in infection rates but relatively little associated disease. Infection rates were highest in seronegative recipients given large amounts of fresh blood. Recently published reports have shown substantially lower infection rates than earlier studies, a change likely to be due to the current practice of transfusing fewer units of older blood. CMV has not been found to play a significant role in the etiology of posttransfusion hepatitis. CMV infections have been found to be an important source of morbidity and mortality in immunocompromised patients. Several studies of transfused, premature infants have shown significant differences in infection rates and disease expression. Seronegative low-birth-weight infants receiving blood from seropositive donors are at greatest risk. Blood from CMV-seronegative donors substantially lowers the risk of infection. Receiving a kidney or heart from a CMV-seropositive donor appears to be a more salient risk factor than blood transfusion in renal and cardiac transplant patients who are also more likely to have symptomatic CMV infections. Leukocyte transfusions have been found to be a significant source of CMV infection and disease in bone marrow transplant patients.(ABSTRACT TRUNCATED AT 250 WORDS)

High risk of non-A non-B hepatitis after a first exposure to volunteer or commercial clotting factor concentrates: effects of prophylactic immune serum globulin

After a first exposure to factor VIII concentrates, 9/9 British patients treated with U.S.A.-derived commercial products, and 10/12 treated with British volunteer (NHS) products, developed acute non-A, non-B (NANB) hepatitis. Hepatitis following commercial products was more severe, and of shorter incubation. High previous exposure to NHS blood products seemed to prevent NHS but not commercial factor VIII-induced hepatitis; the latter was also not attenuated by administration of U.S.A.-derived commercial immune serum globulin (ISG). After a first exposure to NHS factor IX concentrates without ISG, 4/4 patients developed short incubation NANB hepatitis; one also contracted prolonged incubation hepatitis B. One patient treated with ISG and factor IX of proven infectivity did not develop hepatitis, suggesting protection by ISG. Observed differences between concentrates might be attributable to their content of different NANB agents, but dose-related effects could provide alternative explanations. This data provides a basis for comparative assessment of new products of possible reduced infectivity in only small numbers of patients.

Prospective study of post-transfusion hepatitis after cardiac surgery in a British centre

A series of 248 consecutive patients undergoing cardiac surgery were examined in a prospective study of post-transfusion hepatitis in a single British centre. Patients received a total of 1796 units of blood or blood products (mean blood transfusion 6.28 units per patient). During five to 30 days after operation 38 of the patients showed an increase in serum transaminase activities. There was no serological evidence for fresh infection by hepatitis A or B virus, cytomegalovirus, Epstein-Barr virus, or herpes virus in any of these patients. The increase in transaminase activities was unexplained and reached over 100 IU/l (normal less than 40 IU/l) in six patients. The incidence of acute short incubation post-transfusion non-A, non-B hepatitis was therefore thought to be 2.4%. These six patients had normal liver function six months after transfusion but a further two of the surviving 228 patients had raised serum transaminase activities at six months. In one of these, liver biopsy disclosed chronic persistent hepatitis; in the other, alcoholic liver disease was suspected. The incidence of significant chronic liver disease after blood transfusion possibly attributable to a non-A, non-B hepatitis agent was therefore only 0.4%.

Viral hepatitis: a four-year hospital and general-practice study in Sydney 1. Epidemiological features, natural history, and laboratory findings

We studied 761 patients admitted to hospital with viral hepatitis between 1971 and 1974, and 53 patients with viral hepatitis seen in general practice in Sydney, following up some of them for one to two years. We evaluated factors contributing to each type of hepatitis. We noted differences in the patterns in hepatitis A, B and non-A non-B between Anglo-Saxon and non-Anglo-Saxon sectors of the community. All patients with hepatitis A regained normal liver function within 20 months of the acute illness. Of 115 hepatitis B patients seen at 12 months, 6% had chronic hepatitis Bs antigenaemia, 60% had developed anti-HBs antibodies, and 7.3% still had abnormal liver function. Of 20 non-A non-B patients followed for 12 months, liver function was still abnormal in three, but one of these had developed hepatitis B. The case fatality rate for the whole series was 0.66%.

Non-A, non-B viral hepatitis

Non-A, non-B hepatitis is a newly recognized disease entity. Although initially described as a transfusion related viral infection, the disease can occur in sporadic, endemic, and epidemic settings. There are no confirmed, reproducible serologic tests for associated antigens or antibodies, but electron microscopy has revealed virus-like particles of different sizes. Nonspecific laboratory tests of hepatic dysfunction, especially alanine aminotransferase, are currently utilized to diagnose non-A, non-B hepatitis in patients and may be used to implicate blood donor carriers of this virus. The existence of an infectious non-A, non-B hepatitis agent and proof of a chronic carrier state in humans have been documented by transmission studies in chimpanzees. Cross challenge studies in chimpanzees, as well as some epidemiologic data, suggest that more than one agent causes non-A, non-B hepatitis.

Epstein-Barr virus infection in polytransfused patients with homozygous beta-thalassaemia

The frequency of Epstein-Barr virus (EBV) and hepatitis B virus (HBV) infection has been studied in 149 polytransfused thalassaemic patients and in healthy controls. Evidence for EBV infection was based on the detection of antibodies to viral capsid antigen (anti-VCA) and for HBV infection on the detection of either hepatitis B surface antigen (HBsAg) or hepatitis B surface antibody (anti-HBs). The frequency of anti-VCA was not significantly higher in the patients (16.4%) compared to the controls (69.8%) whereas HBV infection was more frequently observed in the patients (91.3%) than in the controls (17.3%). There was also no evidence of repeated infection or recent infection with EBV in the polytransfused patients. These data suggest that transfusion of stored blood does not represent a significant factor of spread for EBV.

Cytomegalovirus infection in the neonate and its prevention

About 0.5% of infants are infected in utero with cytomegalovirus (CMV). As many as 20% become mentally retarded and a further substantial proportion suffer lesser degrees of brain damage. The need for a vaccine is greater than in the case of rubella. A live, tissue culture-adapted strain of CMV has been shown to produce neutralizing antibody in volunteers without significant side effects or detectable virus excretion. The problems of developing such a vaccine for use in man, namely, attenuation, antigenic differences among virus strains, reactivation of latent infection and oncogenicity, are briefly discussed.

[Prospective study in posttransfusion hepatitis in patients with open heart surgery (author's transl)]

In a prospective study in posttransfusion hepatitis 54 patients with open heart surgery received 220 blood units which were negative for HBS Ag by radioimmunoassay. 15 of these units contained anti-HBS and were given to 13 antibody negative patients. In a half year follow up period neither clinical nor biochemical (SGOT, SGPT, gamma-GT) signs of hepatitis could be found in these patients and neither HBS Ag nor anti-HBS developed. At the same time a screening for HBS Ag of hospital staff in contact with these patients revealed no carrier of the antigen. Therefore, the lack of any hepatitis in our relatively small study group may be attributable to two facts: the relative safety of blood screened by highly sensitive methods for the detection of HBS Ag and the noninfectious environment of these patients in the hospital during the observation period.

An outbreak of hepatitis associated with intravenous injection of factor-VIII concentrate

An outbreak of jaundice associated with three out of four batches of a commercial brand of freeze-dried factor-VIII concentrate occurred at the Bournemouth haemophilia centre between April and June, 1974. Seven cases of non-B hepatitis and four of hepatitis B occurred within 6 months of the first use of this product. Two patients contracted both types of hepatitis; thus nine patients became ill out of a total of twenty regularly seen at the centre, eighteen of whom received commercial factor-VIII concentrate.