The declining risk of post-transfusion hepatitis C virus infection

The cost-effectiveness of reducing donor exposures with single-donor versus pooled random-donor platelets

BACKGROUND

Single-donor platelets (SDPs) are frequently preferred over pooled random-donor platelets (RDPs) to reduce donor exposures and the risk for virus transmission or HLA alloimmunization. Transfusion-associated virus-transmission risks have significantly decreased, which suggests that white cell reduction by filtration eliminates any difference in the risk of alloimmunization in transfused leukemic patients. Health care reform pressures of make it appropriate to examine the cost-effectiveness of SDPs versus RDPs in reducing donor exposures.

STUDY DESIGN AND METHODS

A decision analysis model was developed and sensitivity analyses were used to assess the incremental cost (dollars/quality-adjusted life-year) associated with the use of SDPs versus RDPs for adult patients undergoing hematopoietic progenitor cell transplantation or primary coronary artery bypass grafting (CABG).

RESULTS

Among transplant patients, the incremental cost of choosing SDPs as opposed to RDPs ranged from $168,700 to $519,822 per quality-adjusted life-year. For patients undergoing primary CABG, the incremental cost was $192,415 (females) and $216,280 (males). Variations in the cost differential between SDPs and RDPs, the number of random-donor platelets in the RDP, and the risk of bacterial sepsis markedly influenced cost-effectiveness. The model was minimally affected by variations in the risks of transmission of HIV and hepatitis B and C, and human T-lymphotropic viruses.

CONCLUSION

In comparison with other accepted medical interventions, the use of SDPs as opposed to RDPs may not be a cost-effective method of reducing donor exposures in the adult patient populations studied. SDPs were more cost-effective in patients undergoing primary CABG than in leukemia patients undergoing hematopoietic progenitor cell transplantation. Regardless of diagnosis, decreasing the acquisition cost differential would have the greatest impact on improving the cost-effectiveness of SDPs, as opposed to RDPs, to decrease donor exposures.

Hepatitis C virus genotype does not affect patient survival among renal transplant candidates. The New England Organ Bank Hepatitis C Study Group

BACKGROUND

Patients with end-stage renal disease (ESRD) are at increased risk for infection with different hepatitis C virus (HCV) genotypes and multiple genotype infections. However, to date, the effect of the type and number of infecting HCV genotypes on survival among ESRD patients has not been carefully examined, and this was the objective of this study.

METHODS

Sera from patients on the renal transplant waiting list at the New England Organ Bank between November 1986 and June 1990 were tested for anti-HCV using a third-generation enzyme-linked immunosorbent assay. All anti-HCV-positive serum samples were tested for HCV RNA by reverse transcriptase "nested" polymerase chain reaction (PCR) with primers derived from the highly conserved 5'UTR region of the HCV genome. HCV genotypes were determined by restriction fragment length polymorphism of the 5'UTR PCR product. The duration of follow-up was calculated from the date of the first available serum specimen until death, loss to follow-up, or December 31, 1995, whichever occurred earlier. Two separate multivariate models were constructed: one to examine the impact of HCV genotype on mortality and the other to examine the impact of the single versus mixed infection on mortality. In both models, the independent variables were HCV genotype and transplantation. The HCV genotype was treated as a time-independent (baseline) variable. Transplantation was treated as a time-dependent variable in which the status changed after transplantation.

RESULTS

HCV RNA was detected by PCR in 224 patients (81%) in whom sera were available. Complete clinical data on baseline covariates, subsequent transplantation, and mortality were available in 180 patients (80%), and these patients constituted the final study cohort. HCV genotypes 1a and 1b were the two most common genotypes encountered and were found in 60 and 24% of the patients, respectively. One hundred and sixty-two (90%) patients were infected with a single HCV single genotype, 16 patients (9%) with two genotypes, and two patients (1%) with three genotypes. Among the 180 patients in the final study cohort, 86 (48%) underwent transplantation, and 66 (37%) patients died during follow-up. Compared with patients infected with HCV genotype 1a, the relative risk (RR) of death from all causes was not significantly increased among patients infected with genotype 1b (RR = 1.02, 95% CI, 0.55 to 1.89) or other genotypes (RR = 1.08, 95% CI, 0.50 to 2.30). Likewise, compared with patients with a single infection, the RR of death among patients with mixed infection (RR = 1.18, 95% CI, 0.52 to 2.66) was not significantly increased.

CONCLUSIONS

The results of this study suggest that the type and number of HCV genotypes may not have a significant impact on survival among ESRD patients.

Screening for HBV, HCV and HIV genomes in blood donations: shortcomings of pooling revealed by a multicentre study simulating real-time testing

This study was undertaken in order to determine whether screening of viremic blood donations by testing of pooled donor samples could constitute a technically feasible transfusional safety measure. A pilot study of real-time simulation, on a day-to-day basis, of screening of three viral genomes (hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV)) was conducted by five French Blood Centers on plasma samples collected from blood donors and studied within undiluted samples and within sample pools of various sizes. This study was carried out within time conditions compatible with the release of platelets. For the detection of HCV and HIV genomes, the five laboratories achieved a sensitivity that decreased with the size of the sample pool. Four were successful in detecting all undiluted samples. In the 1/10 diluted samples, four failed to detect one HIV or HCV sample. In the 1/100 diluted samples, all laboratories failed to detect one or more HIV or HCV samples. For HBV genome, no participating laboratories detected all of the samples of the panel, even undiluted samples, and the sample pooling considerably affected sensitivity. The improvement and standardization of assays needs to be attained, and training of laboratories appears to be a step crucial for routine screening of viral genomes in blood donations.

Hepatitis C virus infection and bone marrow transplantation: a cohort study with 10-year follow-up

Before the introduction of routine blood donor screening in 1991, marrow transplant recipients were at significant transfusion-associated risk for infection with hepatitis C virus (HCV). We followed a cohort of 355 patients undergoing transplant in Seattle during 1987 to 1988 to determine (1) the impact of pretransplant HCV infection on the occurrence and severity of venocclusive disease (VOD); (2) the impact of HCV infection on liver dysfunction, other than VOD, occurring between 21 and 60 days after transplantation; and (3) the natural history of post-transplant HCV liver disease with a 10-year follow-up. HCV-RNA status was determined on serum stored before transplant and at day 100 post-transplant. Sixty-two (17%) patients were HCV-RNA positive before transplant, and 113 (32%) were HCV-RNA positive by day 100 post-transplant (or before death). Severe VOD developed in 22 of 46 (48%) evaluable patients with pretransplant HCV infection and in 150 of 229 (14%) evaluable patients without HCV (P <.0001). In multivariable analysis of risk factors for developing VOD, pretransplant HCV infection associated with elevated serum aspartate transaminase (AST) levels predicted the development of severe VOD (relative risk, 9.6; P =.0001). The presence of HCV with normal AST levels before transplant was not a risk factor for severe VOD. Between 21 and 60 days after transplant, HCV-RNA positive-patients had higher AST levels (median 101 U/L), but similar alkaline phosphatase and total bilirubin levels compared with HCV-negative patients, suggesting that cholestatic liver disease (particularly graft-versus-host disease [GVHD]) was not related to HCV infection. An acute flare of hepatitis (AST >10 times the upper limit of normal) developed at a mean of 136 +/- 58 days in 31% of HCV-positive patients; no patients developed fulminant hepatitis. Between 5 and 10 years after transplant, 57% of HCV-positive and 6% of HCV-negative patients had mild to moderate elevations of AST (P <. 0001), but HCV infection was not associated with excess mortality between 3 and 10 years after bone marrow transplantation. In summary, HCV infection with elevated AST levels is a significant risk factor for severe VOD after marrow transplant. However, the decision to proceed to transplantation in HCV-positive patients must balance the absolute risk of death from VOD against the risks of the underlying disease. In long-term survivors, HCV infection is not associated with excess mortality over 10 years of follow-up.

Infection by an unenveloped DNA virus associated with non-A to -G hepatitis in Japanese blood donors with or without elevated ALT levels

BACKGROUND

An unenveloped, single-stranded DNA virus named TT virus has been found in association with elevated alanine aminotransferase (ALT) levels in recipients of transfusions and has been detected frequently in patients with acute or chronic hepatitis of non-A to -G etiology in Japan. DNA of the TT virus was searched for in blood donors with or without elevated ALT levels.

STUDY DESIGN AND METHODS

A total of 861 blood donors without previous transfusions and who were negative for markers of hepatitis B or C virus infection were tested. DNA of the TT virus was detected by polymerize chain reaction with hemi-nested primers.

RESULTS

TT virus DNA was detected in 62 of 280 (22.1% [95% CI: 18.1-26.6]) donors with elevated ALT levels (mean +/- SD, 89.3 +/- 36.4 U/L; range, 61-301 U/L), which is significantly more frequently (p<0.02) than its detection in 91 of 581 (15.7% [95% CI: 13.2-18.4]) donors with normal ALT (< or = 45 U/L). The frequency of TT virus DNA increased with age, in donors with and without elevated ALT.

CONCLUSION

The detection of TT virus DNA, at a frequency higher in donors with elevated ALT than in those without, strengthens the association of TT virus with non-A to -G hepatitis.

Clinical outcomes after hepatitis C infection from contaminated anti-D immune globulin. Irish Hepatology Research Group

BACKGROUND AND METHODS

In February 1994, batches of anti-D immune globulin used in Ireland during 1977 and 1978 to prevent Rh isoimmunization were found to be contaminated with hepatitis C virus (HCV) from a single infected donor. In March 1994, a national screening program was initiated for all women who had received anti-D immune globulin between 1970 and 1994. Of the 62,667 women who had been screened when this study began, 704 (1.1 percent) had evidence of past or current HCV infection, and 390 of those 704 (55 percent) had positive tests for serum HCV RNA on reverse-transcription-polymerase-chain-reaction analysis. All 390 were offered a referral for clinical assessment and therapy. We evaluated 376 of these 390 women (96 percent); the other 14 were not seen at one of the designated treatment centers.

RESULTS

The mean (+/-SD) age of the 376 women was 45+/-6 years at the time of screening. They had been infected with hepatitis C for about 17 years. A total of 304 women (81 percent) reported symptoms, most commonly fatigue (248 [66 percent]). Serum alanine aminotransferase concentrations were slightly elevated (40 to 99 U per liter) in 176 of 371 women (47 percent), and the concentrations were 100 U per liter or higher in 31 (8 percent). Liver biopsies showed inflammation in 356 of 363 women (98 percent); in most cases the inflammation was slight (41 percent) or moderate (52 percent). Although the biopsy samples from 186 of the 363 women (51 percent) showed evidence of fibrosis, only 7 women (2 percent) had probable or definite cirrhosis. Two of the seven reported excessive alcohol consumption.

CONCLUSIONS

Most of the women with HCV infection 17 years after receiving HCV-contaminated anti-D immune globulin had evidence of slight or moderate hepatic inflammation on liver biopsy, about half had fibrosis, and 2 percent had probable or definite cirrhosis.

Risk factors for acquisition of hepatitis C virus infection in blood donors: results of a case-control study

BACKGROUND & AIMS

Few studies have explored risk factors predicting hepatitis C virus (HCV) infection in blood donors; their results are contradictory. The aim of this study was to evaluate the association between HCV infection and various risk factors in Canadian volunteer blood donors.

METHODS

Four transfusion centers were involved in this case-control study. A total of 267 confirmed anti-HCV-positive blood donors were interviewed along with 1068 seronegative blood donors matched for sex, age, donation site, and date. Information was collected using a structured telephone interview. The main outcome measures were odds ratios (ORs) and 95% confidence intervals (CIs) for various risk factors from univariate and multivariate analyses using conditional logistic regression.

RESULTS

By univariate analysis, 23 variables were associated with anti-HCV positivity. In the final multivariate analysis, only 5 factors remained independently predictive of HCV infection: previous intravenous drug use (OR, 127.5; 95% CI, 26.0-625.0), having lived in a prison or juvenile detention center (56.1; 11.4-275.7), previous blood transfusion (10.5; 4.7-23.2), sexual contact with an intravenous drug user (6.9; 3.1-15.2), and tattooing (5.7; 2.5-13).

CONCLUSIONS

Most blood donors acquire infection by percutaneous exposure to contaminated blood. A role for sexual transmission is suggested by this study.

A Prospective Study on TT Virus Infection in Transfusion-Dependent Patients With β-Thalassemia

A novel DNA virus designated TT virus (TTV) has been reported to be involved in the development of posttransfusion non–A-C hepatitis. We evaluated the frequency and natural course of TTV infection in a cohort of transfusion-dependent thalassemic patients in a 3-year follow-up study. Ninety-three serum hepatitis C virus (HCV) antibody-negative patients (median age of 8 years; range, 0 to 25) from eight centers were studied. Of them, 34 (37%) had an abnormal alanine-aminotransferase (ALT) baseline pattern, and the other 12 (13%) showed ALT flare-ups during the follow-up. TTV DNA in patient sera collected at the time of enrollment and at the end of follow-up was determined by polymerase chain reaction (PCR). In parallel, serum samples from 100 healthy blood donors were also tested. At baseline, 87 patient sera (93.5%) tested positive for the TTV DNA. Of these TTV DNA-positive patients, 84 (96.5%) remained viremic at the end of the study period. Of the 6 TTV DNA-negative patients, 3 acquired TTV infection during follow-up. However, no definite relation was observed between the results of TTV DNA determination and ALT patterns. TTV viremia was also detectable in 22% of blood donors. In conclusion, TTV infection is frequent and persistent among Italian transfusion-dependent patients. The high rate of viremia observed in healthy donors indicates that the parenteral route is not the only mode of TTV spread.

A Prospective Study on TT Virus Infection in Transfusion-Dependent Patients With β-Thalassemia

A novel DNA virus designated TT virus (TTV) has been reported to be involved in the development of posttransfusion non–A-C hepatitis. We evaluated the frequency and natural course of TTV infection in a cohort of transfusion-dependent thalassemic patients in a 3-year follow-up study. Ninety-three serum hepatitis C virus (HCV) antibody-negative patients (median age of 8 years; range, 0 to 25) from eight centers were studied. Of them, 34 (37%) had an abnormal alanine-aminotransferase (ALT) baseline pattern, and the other 12 (13%) showed ALT flare-ups during the follow-up. TTV DNA in patient sera collected at the time of enrollment and at the end of follow-up was determined by polymerase chain reaction (PCR). In parallel, serum samples from 100 healthy blood donors were also tested. At baseline, 87 patient sera (93.5%) tested positive for the TTV DNA. Of these TTV DNA-positive patients, 84 (96.5%) remained viremic at the end of the study period. Of the 6 TTV DNA-negative patients, 3 acquired TTV infection during follow-up. However, no definite relation was observed between the results of TTV DNA determination and ALT patterns. TTV viremia was also detectable in 22% of blood donors. In conclusion, TTV infection is frequent and persistent among Italian transfusion-dependent patients. The high rate of viremia observed in healthy donors indicates that the parenteral route is not the only mode of TTV spread.

Chronic liver disease in central Harlem: the role of alcohol and viral hepatitis

For reasons not yet determined, chronic liver disease (CLD) has been a leading cause of excess morbidity and mortality in central Harlem. We conducted a case series and case-control analysis of demographic, clinical, epidemiological, and alcohol-intake-related information from patients with CLD and age- and sex-matched hospitalized control patients. Patients' sera were tested for markers of viral hepatitis. The presumed etiology of CLD among case-patients was as follows: both alcohol abuse and hepatitis C virus (HCV) infection, 24 persons (46% of case-patients); alcohol abuse alone, 15 (29%); HCV infection alone, 6 (12%); both alcohol abuse and chronic hepatitis B virus (HBV) infection, 3 (6%); and 1 each (2%) from: 1) schistosomiasis, 2) sarcoidosis, 3) unknown causes, and 4) alcohol abuse, chronic HBV, and HCV combined. In the case-control analysis, patients who had both alcoholism and either HBV (odds ratio [OR]: 6.3; 95% CI: 0. 5-334) or HCV (OR: 2.9; 95% CI: 1.3-6.2) were at increased risk for CLD, whereas patients who had only one of these three factors were not at increased risk for CLD. Patients who tested positive for the hepatitis G virus (HGV) did not have a significantly increased risk of CLD, and neither severity of CLD nor mortality was greater among these patients. Most patients in central Harlem who had CLD had liver damage from a combination of alcohol abuse and chronic viral hepatitis. Alcohol and hepatitis viruses appear to be synergistically hepatotoxic; this synergy appears to explain both the high rate of CLD in central Harlem and the recent reductions in this rate. Persons at risk for chronic HBV and HCV infection should be counseled about their increased risk of CLD if they consume excessive alcohol. Morbidity and mortality from liver disease could be decreased further by a reduction in alcohol consumption among persons who have chronic HBV and HCV infection, avoidance of needle sharing, and hepatitis B vaccination.

Quantification of liver iron overload by T2 quantitative magnetic resonance imaging in thalassemia: impact of chronic hepatitis C on measurements

PURPOSE

Measurement of liver T2 values seems to be an accurate and sensitive magnetic resonance imaging (MRI) method for the quantification of liver hemosiderosis in multiple transfused patients with thalassemia. Because many of these patients have coexistent chronic hepatitis C virus (HCV) infection, the effect of inflammatory changes on liver T2 values was assessed.

MATERIALS AND METHODS

Liver MRI studies of 35 HCV+ and 17 HCV- patients with beta-thalassemia, 9 HCV+ patients without thalassemia, and 10 healthy controls of the same age range (13 to 32 years) were reviewed. Iron status was assessed by serum ferritin in all patients, and determination of liver iron concentration (LIC) was available in 16 HCV+ patients with thalassemia. Histologic activity index (HAI) and grades of siderosis were evaluated in all HCV+ patients with thalassemia.

RESULTS

Patients with thalassemia had significantly lower T2 values (P < 0.0001) than subjects without thalassemia, whereas no difference existed between HCV+ patients without thalassemia and healthy controls. In HCV+ patients, LIC correlated more nearly with T2 values (r = 0.93) than with serum ferritin (r = 0.73). T2 values were not influenced by HAI score or fibrosis.

CONCLUSION

Liver T2 values were found to be more accurate than serum ferritin in predicting liver iron overload and were not influenced by the presence of chronic hepatitis C. Therefore, MRI could serve as a noninvasive alternative to liver biopsy for the quantification of hemosiderosis in HCV+ patients with thalassemia.

A prospective, randomized study of cardiopulmonary bypass temperature and blood transfusion

BACKGROUND

We hypothesized that normothermic cardiopulmonary bypass (CPB) would be associated with decreased blood loss and allogeneic transfusion requirements relative to hypothermic CPB.

METHODS

After obtaining institutional review board approval and informed patient consent, we conducted a prospective, randomized study of 79 patients undergoing CPB for a primary cardiac operation at normothermic (37 degrees C) (n = 44) or hypothermic temperature (25 degrees C) (n = 35). Blood loss and transfusion requirements in the operating room and for the first 24 hours in the intensive care unit were determined. A paired t test and rank sum tests were used. A p value of less than 0.05 was considered significant.

RESULTS

The normothermic and hypothermic CPB groups did not differ in demographic variables, CPB or cross-clamp duration, heparin sodium or protamine sulfate dose, prothrombin time, or thromboelastogram results. There were no differences between the two CPB groups in blood loss or transfusion requirements.

CONCLUSIONS

We found that when there was no difference in duration of CPB, normothermic and hypothermic CPB groups demonstrated similar blood loss and transfusion requirements even though other studies have shown hypothermia induces platelet dysfunction and alters the activity of the coagulation cascade.

Risk factors of hepatitis C virus infection in patients on hemodialysis: a multivariate analysis based on a dialysis register in Central Italy

A seroprevalence survey of antibodies to HCV was carried out among 2788 hemodialysis (HD) patients in a region of central Italy. Anti-HCV seroprevalence was 28.6%. A multivariate analysis of risk factors showed a significant association with time on HD, history of blood transfusion and metropolitan area of residence. Our study clearly showed that HCV infection is common among HD patients and is partially associated with preventable factors.

Hepatitis C virus infection in dialysis: a continuing problem

Patients on chronic dialysis are at increased risk of acquiring parenterally transmitted hepatitis viruses from blood product transfusions or nosocomial transmission in hemodialysis units, and biochemical abnormalities in liver function are seen in 10-44% of patients on chronic hemodialysis. In the past, hepatitis B virus (HBV) was the major cause of parenterally transmitted viral hepatitis in dialysis patients, and the remaining cases were attributed to non-A, non-B hepatitis (NANBH). The discovery of the hepatitis C virus (HCV) has shed light on the cause and clinical course of NANBH in patients on dialysis. The current debate is focused on strategies to reduce the transmission of HCV among dialysis patients and to lessen the consequences of liver disease among patients already infected.

A Multicenter Prospective Study on the Risk of Acquiring Liver Disease in Anti–Hepatitis C Virus Negative Patients Affected From Homozygous β-Thalassemia

Although the risk of transfusion-transmitted hepatitis has been recently reduced, transfusion-dependent β-thalassemia patients may still develop liver disease due to viral infection or iron overload. We assessed the frequency and causes of liver dysfunction in a cohort of anti–hepatitis C virus (HCV) negative thalassemics. Of 1,481 thalassemics enrolled in 31 centers, 219 (14.8%) tested anti-HCV− by second-generation assays; 181 completed a 3-year follow-up program consisting of alanine-aminotransferase (ALT) measurement at each transfusion and anti-HCV determination by third-generation enzyme-immunoassay (EIA-3) at the end of study. Serum ferritin levels were determined at baseline and at the end of follow-up. Ten patients were anti-HCV+ by EIA-3 at the end of follow-up. Of them, seven were already positive in 1992 to 1993 when the initial sera were retested by EIA-3, one tested indeterminate by confirmatory assay, and two had true seroconversion (incidence, 4.27/1,000 person years; risk of infection, 1/7,100 blood units, 95% confidence interval [CI], 1 in 2,000-1 in 71,000 units). At baseline, 67 of 174 thalassemics had abnormal ALT. Of those with normal ALT, seven subsequently developed at least one episode of moderate ALT increase (incidence, 24.6/1,000 person-years). All of the 20 patients with ferritin values ≥3,000 ng/mL had clinically relevant ALT abnormalities, as compared with 53 of 151 with &lt;3,000 ng/mL (P&lt; .005). Hepatic dysfunction is still frequent in thalassemics. Although it is mainly attributable to siderosis and primary HCV infection, the role of undiscovered transmissible agents cannot be excluded.

© 1998 by The American Society of Hematology.

A Multicenter Prospective Study on the Risk of Acquiring Liver Disease in Anti–Hepatitis C Virus Negative Patients Affected From Homozygous β-Thalassemia

Although the risk of transfusion-transmitted hepatitis has been recently reduced, transfusion-dependent β-thalassemia patients may still develop liver disease due to viral infection or iron overload. We assessed the frequency and causes of liver dysfunction in a cohort of anti–hepatitis C virus (HCV) negative thalassemics. Of 1,481 thalassemics enrolled in 31 centers, 219 (14.8%) tested anti-HCV− by second-generation assays; 181 completed a 3-year follow-up program consisting of alanine-aminotransferase (ALT) measurement at each transfusion and anti-HCV determination by third-generation enzyme-immunoassay (EIA-3) at the end of study. Serum ferritin levels were determined at baseline and at the end of follow-up. Ten patients were anti-HCV+ by EIA-3 at the end of follow-up. Of them, seven were already positive in 1992 to 1993 when the initial sera were retested by EIA-3, one tested indeterminate by confirmatory assay, and two had true seroconversion (incidence, 4.27/1,000 person years; risk of infection, 1/7,100 blood units, 95% confidence interval [CI], 1 in 2,000-1 in 71,000 units). At baseline, 67 of 174 thalassemics had abnormal ALT. Of those with normal ALT, seven subsequently developed at least one episode of moderate ALT increase (incidence, 24.6/1,000 person-years). All of the 20 patients with ferritin values ≥3,000 ng/mL had clinically relevant ALT abnormalities, as compared with 53 of 151 with <3,000 ng/mL (P< .005). Hepatic dysfunction is still frequent in thalassemics. Although it is mainly attributable to siderosis and primary HCV infection, the role of undiscovered transmissible agents cannot be excluded.

© 1998 by The American Society of Hematology.

The use of polymerase chain reaction in plasma pools for the concomitant detection of hepatitis C virus and HIV type 1 RNA

BACKGROUND

Detection of viral nucleic acids might increase blood transfusion safety through the detection of recently infected blood donors during the preseroconversion window period. Individual screening is difficult to apply, because of technical and financial constraints.

STUDY DESIGN AND METHODS

A polymerase chain reaction (PCR)-based assay including a polyethylene glycol precipitation step was developed for the concomitant detection of hepatitis C virus (HCV) and HIV type 1 (HIV-1) RNA in plasma pools corresponding to 50 blood donations by the use of commercial assays.

RESULTS

The assay had a sensitivity of less than 33 copies per mL for HCV RNA and 1000 copies per mL for HIV-1 RNA for each individual sample included in the pool. The eight preseroconversion samples with HCV RNA between 1,250 and 762,000 copies per mL were all detected when 100-microL aliquots from the samples were introduced into 5-mL pools of 50 blood donations.

CONCLUSIONS

A PCR-based pooling assay associating a prepurification step with polyethylene glycol allows for the screening of blood donations for HCV and HIV-1 RNA without marked loss of sensitivity from that seen with commercially available assays. This procedure might increase blood safety through systematic screening of blood donations at relatively low cost.

Hematocrit value on intensive care unit entry influences the frequency of Q-wave myocardial infarction after coronary artery bypass grafting. The Institutions of the Multicenter Study of Perioperative Ischemia (McSPI) Research Group

OBJECTIVES

No data exist regarding "the best" hematocrit value after coronary artery bypass graft surgery. Transfusion practice varies, because neither an optimal hematocrit value nor a uniform transfusion trigger criterion has been determined.

METHODS

To investigate the optimal hematocrit value, we studied 2202 patients undergoing coronary bypass. The hematocrit value on entry into the intensive care unit (IHCT) was categorized into three groups: high (> or = 34%), medium (25% to 33%), and low (< or = 24%). Characteristics and adverse events (outcomes) were compared, and the effect of IHCT on the risk of myocardial infarction was determined by logistic regression.

RESULTS

High IHCT (> or = 34%) was associated with an increased rate of myocardial infarction (8.3% vs 5.5% vs 3.6%; p < or = 0.03, high, medium vs low) and with more severe left ventricular dysfunction (11.7% vs 7.4% and 5.7%; p=0.006, high, medium vs low). Mortality rate increased with higher IHCT when all the high-risk subgroups were combined (8.6% vs 4.5% vs 3.2%; p < 0.001, high, medium vs low). By multivariate analysis, IHCT remained the most significant predictor of adverse outcomes (relative risk high vs low 2.22, 95% confidence interval: 1.04 to 4.76). No characteristic, event, medication, or transfusion therapy confounded the relationship between IHCT and outcome.

CONCLUSION

High IHCT is associated with a higher rate of myocardial infarction and is an independent predictor of infarction. On the basis of the risk of myocardial infarction, there is no rationale for transfusion to an arbitrary level after coronary artery bypass grafting.

Pilot study to estimate survivors to 1995 of 1983-1984 prevalent hepatitis C infections in Lothian patients who tested positive or negative for hepatitis B surface antigen in 1983-1984

OBJECTIVE

To estimate Hepatitis C prevalence in 1983-1984, and survivorship to 1 January 1995, of patients who tested were for Hepatitis B surface antigen in 1983-1984; and to do so according to risk of blood-borne virus transmission, including injector status.

SETTING

Regional Virus Laboratory in Edinburgh.

SAMPLES

Sera from 1983-1984 which were originally received for hepatitis B surface antigen testing and were classified as being at high, medium, or low risk for blood-borne virus transmission.

RESULTS

Available 1983-1984 sera were tested from: (i) all 246 patients aged 15-55 years who were Hepatitis B surface antigen positive in 1983-1984; and (ii) a 10% systematic sample of 355 patients aged 15-55 years who had tested Hepatitis B surface antigen negative in 1983-1984. Patients' survival status at 1 January 1995 was established via the records of the Registrar General for Scotland. A Hepatitis C prevalent case cohort of 500 survivors to 1 January 1995- who were already infected with Hepatitis C in 1983-1984--could be established from group (i) and high or medium risk group (ii) patients with, as controls, 1460 individuals of similar age and risk group whose 1983-1984 sample was negative when tested retrospectively for Hepatitis C antibodies. Two hundred out of these 500 cases are not known to be injecting drug users, and the total would rise to 300 out of 600 if the case cohort were expanded to include low risk group (ii) surviving patients who were Hepatitis C antibody positive in 1983-1984. Between 82% (40/49) and 97% of injectors (57/59 if also HIV-infected) who were Hepatitis B surface antigen positive in 1983-1984 were already Hepatitis C antibody positive; and 72% (95% confidence interval (CI) 51%-93%) of injectors who were Hepatitis B surface antigen negative in 1983-1984 were nonetheless infected with Hepatitis C. Known drug user/contacts (excluding the major group of 59 identified HIV-infecteds) had Hepatitis C prevalence in 1983-1984 of 79% (53/67, with 95% CI 69%-89%), substantially higher than our prior assumption, which was 50%. Hepatitis C prevalence in 1983-1984 for patients who were not known to be injectors, were Hepatitis B surface antigen negative and were rated as moderate risk for blood-borne virus transmission was 13% (95% CI 4%-23%) and 8% (95% CI 3%-14%) even for low risk patients. Deaths by end December 1994 in 1983-1984 prevalent Hepatitis C infections were low: 2/35 (6%) for patients who were Hepatitis B surface antigen negative in 1983-1984 and 2/40 (5%) for Hepatitis B surface antigen positive injectors who were not HIV-infected. The latter rate with upper 95% confidence limit of 12% is modest when compared to the 10% mortality that would be expected of injectors over 11 years.

CONCLUSION

Retrospective Hepatitis C testing of 1700 stored sera from high or medium risk group (ii) patients who were not known to be injectors will identify an estimated 200 (11.7%) who were already Hepatitis C infected in 1983-1984 and still alive on 1 January 1995. Retrospective Hepatitis C testing of 1300 low risk samples is expected to yield 100 (7.6%) apparently non-injector patients who were already Hepatitis C infected in 1983-1984 and still alive on 1 January 1995.

Cost-effectiveness of recombinant human erythropoietin in the prevention of chemotherapy-induced anaemia

Recombinant human erythropoietin (rHuEPO) has been advocated for the treatment of anaemia in patients submitted to cancer chemotherapy. We used decision analysis to compare the cost-effectiveness of rHuEPO supplemented with red blood cell (RBC) transfusions with conventional treatment with RBC transfusions alone. At baseline, we analysed the use of rHuEPO as secondary prophylaxis according to effectiveness estimates from a community-based oncology study. In order to reduce the probability of transfusions from 21.9% to 10.4%, and the number of RBC units per patient per month from 0.55 to 0.29, 150 units kg(-1) s.c. rHuEPO three times per week for 4 months resulted in an incremental cost of $189,652 per quality-adjusted life year (QALY). In patients treated with cisplatin-containing chemotherapy, rHuEPO added $190,142 per QALY. In a hypothetical scenario of a transfusion pattern that maintained the same haemoglobin level of rHuEPO-responsive patients, the marginal cost of rHuEPO was always greater than $100,000 per QALY. Results were stable with regard to variations in the probability of blood-borne infections, quality of life of responding patients and cancer-related mortality. The additional cost could be lowered to less than $100,000 per QALY by saving 4.5 RBC units over 4 months for any patient treated. In conclusion, according to current use, rHuEPO is not cost-effective in the treatment of chemotherapy-induced anaemia. More tailored utilization of the drug and better consideration of predictive response indicators may lead to an effective, blood-sparing alternative.

A prospective study of the risk of transfusion-acquired viral infections

The risk of transfusion-transmitted viral infections may be estimated by several methods, but only prospective studies of transfusion recipients can directly measure the incidence, with associated 95% upper confidence bound, of these infections. From 1989 through 1995, 764 recipients of allogeneic or autologous red blood cell transfusions were enrolled; 486 (64%) provided both pretransfusion and 6-month follow-up specimens. Both specimens were tested for anti-HBc, anti-HCV, anti-HTLV-I and anti-HIV, with appropriate confirmatory testing. Thirty-nine (8.0%) subjects had seroprevalent anti-HBc, 19 (3.9%) subjects had seroprevalent anti-HCV, three (0.6%) subjects had seroprevalent anti-HTLV-I/II, and one (0.2%) subject had seroprevalent anti-HIV. There were no seroconversions for any agent among the 34 patients who received only autologous blood, and no confirmed seroconversions for anti-HTLV-I or anti-HIV among all subjects. There were three seroconversions for anti-HBc (incidence 1.04 x 10(-3); 95% confidence interval (CI) 2.15 x 10(-4), 3.05 x 10(-3) per allogeneic unit transfused), and two confirmed seroconversions for HCV (incidence 6.94 x 10(-4); 95% CI 8.34 x 10(-5), 2.51 x 10(-3) per allogeneic unit transfused). One of the two anti-HCV seroconversions occurred in March 1994, after the institution of HCV EIA 2.0 screening of donated blood. Transfusion-associated seroconversions to hepatitis B and C markers were observed at low rates in the early 1990s despite testing donors for markers of both viruses, whereas seroconversions to HTLV-I or HIV were less than 1.04 x 10(3) per allogeneic unit transfused, based upon the upper 95% confidence interval of the zero incidence in this study.

Sex differences in mortality of people who visited emergency rooms for asthma and chronic obstructive pulmonary disease

We assess the sex differences in mortality in a population-based cohort of those Barcelona residents older than 14 yr of age who received emergency room services (ERS) for either chronic obstructive pulmonary disease (COPD) or asthma, during the period from 1985 to 1989. Vital status was followed to the end of 1995. A total of 15,517 individuals, 9,918 males and 5,599 females were included in the study. Asthma was diagnosed in 16% of males and 53% of females. Overall, 50% of males and 30% of females died during the follow-up period. The mortality rates in both males and females who visited emergency rooms for COPD or asthma were significantly higher than the expected rates in the general population. These relative increases in the mortality rates were significantly higher in females than in males for both causes of death, COPD (age-adjusted female/male ratio = 2.39), and asthma (ratio = 3.95). However, survival was better in females than males among individuals in the study. The higher fatality in males than females was observed for all causes of death, all respiratory causes, and COPD (risk ratio among patients with COPD = 0.42, 0.29-0.59, and among patients with asthma = 0.11, 0.02-0.60), but not for asthma. Mortality for asthma was higher in females with a diagnosis of COPD (2.79, 1.52-5.13), but it was not different among individuals in whom asthma was diagnosed (1.02, 0.56-1.87). Greater severity of COPD in males than in females could explain a higher risk of dying for all respiratory causes and COPD in males. The increased risk of asthma death in females may be due to problems of coding the term "asthma" in death certificates. The higher rates in females than in males when comparing with the general population, may be an expression of a greater similarity in risk factors, such as smoking, in our population than in males and females of the general population.

De novo hepatitis C in children after liver transplantation

BACKGROUND

We describe the incidence, results of interferon therapy, and outcome of hepatitis C virus (HCV) hepatitis occurring de novo after pediatric orthotopic liver transplantation (OLT).

METHODS AND RESULTS

Of children undergoing OLT between 1984 and September 1996, 321 children survived for more than 1 year. Of these, 13 (4.0%) developed previously undiagnosed HCV disease, as suggested by HCV antibody testing and HCV polymerase chain reaction and confirmed by liver biopsy. Of the 117 children who received transplants before HCV screening of blood products or donors, 10.2% developed de novo HCV disease. The mean age at diagnosis of HCV hepatitis was 13.2+/-5.0 years, and the mean time to diagnosis after OLT was 8.1 years (range, 4-11 years). The mean alanine aminotransferase (ALT) level at diagnosis was 108 IU/ml, and the liver biopsy specimen showed chronic active or chronic persistent hepatitis in 11 children, cirrhosis in 1 child, and nonspecific changes in 1 child. Twelve children were treated with interferon-2alpha; children who weighed > or =20 kg received 3 x 10(6) units every other day, and those who weighed <20 kg received 1.5 x 10(6) units every other day. Four patients developed rapidly progressive liver failure while receiving interferon therapy and required urgent re-transplantation. Three of the four children again developed histologic evidence of recurrent HCV 4-6 months after the second OLT, and all three subsequently died of HCV-induced liver failure. One patient remains alive and well with no evidence of HCV recurrence and a negative HCV RNA. Of the remaining eight children treated with interferon, only two have had a sustained response (normal ALT) and one is now HCV RNA negative. HCV RNA levels did not correlate with outcome or disease severity. HCV antibody levels were unreliable, with two patients having negative HCV antibody but a positive HCV RNA at diagnosis. Six patients were able to be genotyped: four were la and two were 1b.

CONCLUSION

Overall mortality for de novo HCV hepatitis was 23%. Seventy-five percent of children who received a second transplant for HCV hepatitis had early histologic recurrence that led to liver failure and death. Interferon therapy resulted in a sustained improvement in ALT in only 15% of children. The time to onset and progression of clinical disease both in the original graft and the retransplant graft were accelerated compared with nonimmunosuppressed individuals.

Post-transfusion hepatitis: current risks and causes

Viral hepatitis which follows transfusions (post-transfusion hepatitis) may be due to those transfusions, i.e., transfusion-transmitted hepatitis (TTH), or may be incident to the reason for the transfusion and, thus, may be transfusion-associated, but not transfusion-transmitted. The current risks of TTH, today, are extremely small, but are still due, primarily, to the hepatitis B virus (HBV) and the hepatitis C virus (HCV), the latter, formerly being known as "non-A, non-B hepatitis." The residual, now, of TTH which is non-A, non-B, and non-C is extremely small and may be due to a variety of agents. Using volunteer (unpaid), repeat, blood donors, who are carefully screened for hepatitis risk factors and then tested for evidence of HBV infection, the risk of HBV being transmitted by a transfusion today is in the order of 1 per 63,000 units of blood. For transfusion-transmitted HCV, with the same repeat, volunteer (unpaid) donors, careful screening and a sensitive assay for anti-HCV, the risk is in the order of 1 in 125,000 units. These risks of HBV and HCV due to transfusions are so small that other means of acquiring these viruses should be sought when patients develop hepatitis following blood transfusions. However, efforts to further reduce the current risks of HBV and HCV transmission by transfusions should continue; these include restricting transfusions to those which are necessary or appropriate, utilizing alternatives to transfusion, employing novel assays to detect viral nucleic acids, and, finally, implementing various microbial inactivation techniques on blood, blood components and plasma derivatives.

The impact of risk information on patients' willingness to pay for autologous blood donation

OBJECTIVES

For contingent valuation to provide valid values for policy making, it is important that respondents be well informed about the goods they are asked to value. Few studies, however, have tested the impact of providing this information This study assessed the impact of risk information on patients' willingness to pay for autologous blood donation and derived the willingness to pay in a sample of informed patients.

METHODS

Patients were randomized either to receive information about the risks of complications from allogeneic (volunteer) blood transfusions or to base their willingness to pay responses on their own prior knowledge. Four hundred twelve autologous blood donors were recruited from three study sites. Self-administered questionnaires collected information on willingness to pay, risk perceptions, and socioeconomic information.

RESULTS

As predicted by our theoretical model, providing risk information reduced the variance in the willingness to pay for autologous blood donation. A tendency for information to reduce the willingness to pay was also found, suggesting that uninformed patients, on average, overestimate the risks of allogeneic blood transfusions. The median willingness to pay in the informed sample was approximately $750 to $1,100, depending on the estimation method, compared with $800 to $1,900 in the uninformed group. Willingness to pay was significantly related to perceived transfusion risk, personal income, and dread of transfusions.

CONCLUSIONS

Our results are consistent with an economic model where individuals update their prior risk perceptions with new information. The willingness to pay in the informed sample was far higher than the costs of autologous blood donation, suggesting that total benefits outweigh the costs of the procedure.

Hepatitis C virus infection in acquired aplastic anemia

Hepatitis-associated aplastic anemia (HAAA) is an uncommon disorder that usually is not due to hepatitis A or B virus infection. Hepatitis C virus (HCV) seropositivity is infrequently observed in aplastic anemia (AA) patients who have not been extensively transfused. However, HCV seropositivity may not be detected until several weeks or months after viral infection and AA patients may exhibit defective humoral immunity. Therefore, we evaluated sera from AA patients for the presence of HCV viremia using a reverse transcriptase polymerase chain reaction (RT-PCR) based assay and several serologic assays for HCV antibodies. Serum samples from 90 AA patients who presented to the UCLA Medical Center between March 1984 and February 1990 were analyzed. Overall, 17 patients were found to have HCV viremia by RT-PCR assay, of whom 14 had a positive second-generation HCV enzyme immunoassay (EIA-2) and only 6 were EIA-1 reactive. The frequency of HCV viremia increased with the duration of time between diagnosis and sample procurement, and the number of blood products transfused prior to sampling (P = 0.026). No patient who received fewer than 20 U of blood products or who was sampled less than 20 days after diagnosis had a positive HCV RT-PCR result. Of four patients with hepatitis-associated AA (HAAA), one who was sampled 23 days after diagnosis had hepatitis C viremia and a reactive EIA-2 assay. Therefore, the high frequency of HCV viremia in this patient population is most likely due to transfusion with contaminated blood products prior to the introduction of routine blood donor screening for HCV.

Prospective follow-up study of hepatitis C virus infection in patients undergoing maintenance haemodialysis: comparison among haemodialysis units

A prospective follow-up study on hepatitis C virus (HCV) infection was conducted in seven haemodialysis units from April 1990 to March 1995. A total of 634 patients were undergoing maintenance haemodialysis in the seven units. Of those, 302 patients participated in the follow-up study; 179 were initially HCV antibody negative and 123 were initially positive. Nine of the 179 initially negative patients became positive for HCV antibody during the follow-up period. In accordance with the appearance of HCV antibody, indicating new infection of HCV, all nine of these patients were diagnosed with HCV viraemia. As no other routes were apparent, HCV infection in all nine patients was likely due to nosocomial transmission. Prevalence of HCV antibody at the start of follow up was significantly higher (P < 0.001) in haemodialysis units A-C (37.9%) than in haemodialysis units D-G (17.0%). Incidence of new HCV infection was significantly higher (P = 0.005) in the former units (2.2% per year) than in the latter (0.2% per year). Ten of the 123 patients who were initially positive for the HCV antibody exhibited a loss of reactivity during the follow-up period; of these 10 patients, nine were negative for HCV-RNA from the start of the study. In conclusion, the incidence of new HCV infection seen in patients undergoing haemodialysis suggests that their risk of acquiring HCV infection is directly related to the prevalence of HCV antibody positive patients being treated in the units.

Effects of hepatitis C infection and renal transplantation on survival in end-stage renal disease. The New England Organ Bank Hepatitis C Study Group

Hepatitis C virus (HCV) infection is common among patients with end-stage renal disease (ESRD). However, the effect of HCV infection on survival among ESRD patients, and the impact of renal transplantation on the course of HCV infection has not been adequately defined. Sera from patients on the renal transplant waiting list at the New England Organ Bank between November 1986 and June 1990 were tested for anti-HCV using a third generation ELISA. All anti-HCV positive patients and a 1:1 ratio of randomly selected anti-HCV negative patients comprised the study sample. Duration of follow-up was calculated from the date of the first available serum specimen until death, loss to follow-up or December 31, 1995, whichever occurred earlier. Multivariate analysis of risk factors for mortality was performed using a Cox proportional hazards model which included anti-HCV as a time-independent (baseline) variable, transplantation as a time-dependent (follow-up) variable, and independently significant baseline covariates. Anti-HCV was detected in 287 (19%) of 1544 patients in whom sera were available, and 286 anti-HCV negative patients served as controls. Complete information was available in 496 (87%) of these 573 patients. Median follow-up was 73 months (range 1 to 110 months), during which time 302 (61%) patients underwent renal transplantation and 154 (31%) patients died. For anti-HCV positive patients compared to anti-HCV negative patients, the relative risk of death (and 95% confidence intervals) from all causes was 1.41 (1.01 to 1.97) and due to liver disease or infection was 2.39 (1.28 to 4.48). For patients who underwent transplantation compared to those who remained on dialysis, the relative risk of death from all causes between 0 to 3 months, 3 to 6 months, seven months to four years, and after four years was 4.75 (2.76 to 8.17), 1.76 (0.75 to 4.13), 0.31 (0.18 to 0.54) and 0.84 (0.51 to 1.37), respectively. There was no interaction between the effect of anti-HCV status as baseline and subsequent transplantation (P = 0.93), meaning that the association between treatment modality and survival was similar among anti-HCV positive and negative patients, at all intervals after transplantation. We conclude that HCV infection at the time of referral for transplantation is associated with an increased risk of death, irrespective of whether patients remain on dialysis or undergo transplantation. Transplantation has a beneficial rather than adverse effect on long-term survival in anti-HCV positive patients. Hence, anti-HCV positive status alone is not a contraindication for renal transplantation.

Preoperative autologous blood donation in orthognathic surgery: a follow-up study of 179 patients

Although there have been recent advances in maxillofacial surgery and anaesthetic techniques, blood replacement is still common in orthognathic surgery. 179 patients underwent elective orthognathic surgery and donated autologous blood preoperatively. Standardized questionnaires about the preoperative blood donation were distributed to the patients. Haemoglobin, haematocrit, red blood cells and platelets were measured before blood donation, presurgically and postsurgically, as well as one year after surgery. Nearly all patients (98%) would recommend preoperative autologous blood donation. 97% of the patients saw the benefits of autologous blood donation in avoiding transfusion-transmitted infectious diseases such as acquired immune deficiency syndrome (AIDS) and hepatitis. No serious side-effects have been observed after blood donation. In patients with bimaxillary osteotomies (65% of the predeposited autologous blood units) 41% were in cases having upper jaw osteotomies and only 22% of the preoperatively donated units were retransfused in patients having lower jaw osteotomies. After a postsurgical decrease, the mean haemoglobin and mean haematocrit levels regained the levels determined prior to the donation. Preoperative autologous blood donation of 2 to 3 units (900-1350 ml +/- 10%) of blood is recommended in bimaxillary osteotomies and 1 to 2 units (450-900 ml +/- 10%) of blood for upper jaw osteotomies. In lower jaw surgery, the acute isovolaemic haemodilution should be considered.

Current risks of viral hepatitis from blood transfusions

The incidence of transfusion-associated hepatitis in the United States has fallen dramatically since the late 1960s. Where once the risks were so great that as many as one in three transfused patients contracted hepatitis, now they are infinitesimal. Many factors share responsibility for this accomplishment; however, two stand above the rest: (i) improved donor selection and screening criteria, especially elimination of paid blood donations; and (ii) major advances in testing for viral hepatitis carriers. Currently, four tests are used for the prevention of transfusion-associated hepatitis: (i) hepatitis B surface antigen; (ii) hepatitis C virus antibody; (iii) hepatitis B core antibody; and (iv) alanine aminotransferase. The first two tests are largely responsible for the current low risks of transfusion-associated hepatitis due to hepatitis B virus and hepatitis C virus of 1 in 63,000 and 1 in 125,000, per unit, respectively. To further reduce the risks of transfusion-associated hepatitis will require the enhanced sensitivity provided by nucleic acid amplification techniques (e.g. polymerase chain reaction). Currently, however, no such tests are licensed and practical, automated, or inexpensive enough for individual blood donor screening. We have made such great strides in the prevention of transfusion-transmitted hepatitis that background rates of viral hepatitis now greatly exceed the risk of transmission via transfusion. For this reason, while it may still be reasonable to consider a transfusion as a possible cause for hepatitis, it is imperative that many other possibilities (e.g., iatrogenic and other risk factors) be ruled out.

Frequency, predictors, and appropriateness of blood transfusion after percutaneous coronary interventions

Increased awareness of the risks of blood-borne infections has recently led to profound changes in the practice of transfusion medicine. These changes include, among others, the development of guidelines by the American College of Physicians (ACP) for transfusion. Although the incidence and predictors of vascular complications of percutaneous interventions have been well defined, there are currently no data on frequency, risk factors, and appropriateness of blood transfusions. We performed a retrospective analysis of 628 consecutive percutaneous coronary revascularization procedures. Predictors of blood transfusion were identified using multivariate logistic regression analysis. Appropriateness of transfusions was determined using modified ACP guidelines. Transfusions were administered after 8.9% of interventions (56 of 628). Multivariate analysis identified age >70 years, female gender, procedure duration, coronary stenting, acute myocardial infarction, postprocedural use of heparin and intra-aortic balloon pump placement as independent predictors of blood transfusions (all p <0.05). According to the ACP guidelines, 36 of 56 patients (64%) received transfusions inappropriately. Transfusion reactions (fever) occurred in 10% of patients who received tranfusions appropriately and in 5% of patients who received tranfusions inappropriately. The estimated additional costs per procedure related to transfusions were $551 and $419, respectively. In conclusion, unnecessary transfusions were performed frequently after percutaneous coronary interventions. Application of available guidelines could reduce the number of unnecessary transfusions, thus avoiding exposure of patients to additional risks and reducing procedural costs.

Hepatitis C

Hepatitis C virus (HCV) has emerged as a major cause of chronic liver disease worldwide. The widespread endemicity of HCV infection is the result of a combination of factors, including those related to the genetic diversity of the virus and the host response and those related to the specific settings and behaviors that have facilitated transmission. Most people who contract HCV infection become persistently infected, and the mechanism by which persistent infection is established seems to be related to the lack of development of an effective neutralizing immune response. The magnitude of the spread of HCV infection primarily is related to specific risk factors for transmission. The most important human behavior related to the transmission of HCV has been injection drug use, which in many developed countries has been the leading source of HCV infection during the past 20 to 30 years. The recognition of the clinical importance of HCV infection has resulted in a substantial amount of attention and resources rapidly directed toward developing new and improved therapies. The perception, however, of the public health importance of HCV infection is still limited. Despite the knowledge that injection drug use is the major source of HCV infection in the United States, this message has not been included in prevention and treatment programs, and the resources needed to support strong public health programs have yet to be identified.

[Molecular biology and transfusional viral safety]

In this review we present four fields to which viral molecular biology has contributed: the discovery of blood-borne viruses and the knowledge of the natural history of infection by these viruses; the validation of the results of virological assays used in the biological screening of blood donations; the contribution of molecular biology in inquiries into viral transfusional contamination; the interest of molecular biology in viral transfusional epidemiology. We subsequently deal with the parameters of the discussion on the impact and the feasibility of a systematic screening of several viral genomes in blood donations.

Epidemiology of hepatitis C virus infection among injecting drug users in Australia

STUDY OBJECTIVE

To review the epidemiology of hepatitis C virus (HCV) infection among injecting drug users (IDUs) in Australia, and consider needs for further research and prevention policies and programmes.

DESIGN

(1) Review of the results of surveillance for HCV; (2) review of published literature on prevalence, incidence, and risk factors for HCV among IDUs; and (3) reconstruction of incidence rates from prevalence studies of HCV in IDUs.

SETTING AND PARTICIPANTS

Field and clinic based studies of IDUs in Australia.

MAIN RESULTS

HCV has been present at high prevalences (of the order of 60-70%) in populations of Australian IDUs since at least 1971. Duration of injecting and main drug injected were the main predictors of seropositivity, the latter possibly a surrogate for frequency of injecting and both together as surrogate for cumulative numbers of times injected. Risk of infection begins with first injection and continues as long as injecting does. Current incidence is approximately 15 per 100 person years, and up to 40 per 100 person years in some subpopulations. Incidence may have decreased through the 1980s as a result of behaviour change in relation to HIV, as it has for hepatitis B, but not significantly so.

CONCLUSIONS

Control of HCV infection in Australia will depend on effectiveness of measures to control HCV spread among IDUs. This will be a greater challenge than the control of HIV in this population has been. Needs identified include improved surveillance, especially for recently acquired infection, better understanding of exact transmission modes, and urgent improvement in prevention strategies.

Determination of hepatitis C virus genotypes in the United States by cleavase fragment length polymorphism analysis

We describe the application of a new DNA-scanning method, which has been termed Cleavase Fragment Length Polymorphism (CFLP; Third Wave Technologies, Inc., Madison, Wis.), for the determination of the genotype of hepatitis C virus (HCV). CFLP analysis results in the generation of structural fingerprints that allow discrimination of different DNA sequences. We analyzed 251-bp cDNA products generated by reverse transcription-PCR of the well-conserved 5'-noncoding region of HCV. We determined the genotypes of 87 samples by DNA sequencing and found isolates representing 98% of the types typically encountered in the United States, i.e., types 1a, 1b, 2a/c, 2b, 3a, and 4. Blinded CFLP analysis of these samples was 100% concordant with DNA sequencing results, such that closely related genotypes yielded patterns with strong familial resemblance whereas more divergent sequences yielded patterns with pronounced dissimilarities. In each case, the aggregate pattern was indicative of genotypic grouping, while finer changes suggested subgenotypic differences. We also assessed the reproducibility of CFLP analysis in HCV genotyping by analyzing three distinct isolates belonging to a single subtype. These three isolates yielded indistinguishable CFLP patterns, as did replicate analysis of a single isolate. This study demonstrates the suitability of this technology for HCV genotyping and suggests that it may provide a low-cost, high-throughput alternative to DNA sequencing or other, more costly or cumbersome genotyping approaches.

Hepatitis C infection in transplantation

This review emphasizes the role of HCV in the transplant setting. Prolonged HCV infection results in end-stage liver disease and as such represents a common indication for liver transplantation. Recurrence of infection is almost universal after transplantation in those with viremia before transplantation. Acquired disease is uncommon but nevertheless important, particularly in organ populations in whom screening for infection is not routine. The natural history of post-transplantation disease suggests that the effect on graft or patient survival is minor, at least during short-term follow-up. Long-term follow-up is needed, as well as more detailed study of the factors contributing to severity of post-transplantation disease. Kidney transplant recipients are commonly infected with HCV prior to transplantation. HCV infection after transplantation is associated with an increased risk of liver disease and infectious complications, but its effect on survival is still controversial. Similarly, observations in recipients of other solid organ transplants, such as heart and lung, and bone marrow patients suggest that HCV infection usually is not a major cause of mortality in the first 5 to 10 years of follow-up. Many issues still need to be addressed. The most important is the identification of factors that contribute to disease progression. Finally, effective therapies to eradicate infection and prevent disease progression are awaited.

Incidence and determinants of hepatitis C virus infection among individuals at risk of sexually transmitted diseases attending a human immunodeficiency virus type 1 testing program

BACKGROUND

The role of sexual transmission of hepatitis C virus (HCV) infection is still not completely understood, partly because of the lack of longitudinal studies among cohorts of HCV-negative individuals who engage in at-risk sexual behavior.

GOALS

To evaluate the incidence of HCV infection in a population at risk for human immunodeficiency virus type 1 (HIV-1) infection and other sexually transmitted diseases (STD) and to identify factors associated with HCV seroconversion.

STUDY DESIGN

A retrospective longitudinal study was carried out on a cohort of consecutive attendees of a voluntary HIV-1 testing and counseling program in a large STD center in Rome. All individuals undergoing at least two consecutive tests for HCV antibodies were enrolled. Clinical data and information on individual behavior were collected for all study participants.

RESULTS

Between June, 1992 and December, 1994, a total of 709 individuals (12 intravenous drug users [IDU], 244 homosexuals, and 453 heterosexual non-IDUs), initially negative for HCV antibody, were tested more than once. Among these individuals, 15 HCV seroconversions occurred. The average follow-up time was 1.25 person/years (p/y) for an incidence rate of 1.69 per 100 p/y. The incidence rates by exposure category were 39.30 per 100 p/y among IDUs, 1.37 per 100 p/y among homosexual men, and 0.97 per 100 p/y among heterosexual non-IDUs. Excluding IDUs, of the 697 STD clinic attendees engaging in at-risk sexual behavior, HIV-1-positive status tended to be associated with HCV seroconversion (relative hazard = 5.48; 95% confidence interval = 0.85-35.40). The HCV crude incidence rates among HIV-1-infected patients at enrollment was 11.5%, 4.2%, and 2.4% in those with severe, moderate, and mild levels of immunosuppression, respectively (chi-square for trend = 2.38, P = 0.1).

CONCLUSIONS

In this cohort, HCV infection was confirmed to be strongly associated with intravenous drug use. Nonetheless, the occurrence of two thirds of the total HCV seroconversions in non-IDU individuals engaging in at-risk behavior suggests a role of sexual practices in the transmission of the infection. Among non-IDU individuals, the risk for development of HCV infection tended to increase in those who were HIV-1 infected.

Tranexamic acid reduces bleeding after cardiopulmonary bypass when compared to epsilon aminocaproic acid and placebo

Perioperative bleeding following coronary artery bypass grafting (CABG) is associated with increased blood product usage. Although aprotonin is effective in reducing perioperative blood loss, excessive cost prohibits routine utilization. Epsilon aminocaproic acid (EACA) and tranexamic acid (TA) are inexpensive antifibrinolytic agents, which, when given prophylactically, may reduce blood loss. The present study was undertaken to compare the efficacy of TA and EACA in reducing perioperative blood loss.

METHODS

The study population consisted of first-time CABG patients. Patients were allocated in a prospective double-blind fashion: (1) group EACA (loading dose 15 mg/kg, continuous infusion 10 mg/kg per hour for 6 hours, N = 20); (2) group TA (loading dose 15 mg/kg, continuous infusion 1 mg/kg per hour for 6 hours, N = 20); (3) control group (infusion of normal saline for 6 hours, N = 19).

RESULTS

Treatment groups were similar preoperatively. No significant difference in intraoperative blood loss or perioperative use of blood products was noted. D-dimer concentration was elevated in the control group compared to the EACA and TA groups (p < 0.05). Group TA had less postoperative blood loss than the EACA and control groups at 6 and 12 hours postoperatively (p < 0.05). TA had reduced total blood loss (600 +/- 49 mL) postoperatively compared to EACA (961 +/- 148 mL) and control (1060 +/- 127 mL, p < 0.05).

CONCLUSION

TA and EACA effectively inhibited fibrinolytic activity intraoperatively and throughout the first 24 hours postoperatively. TA was more effective in reducing blood loss postoperatively following CABG. This suggests that TA may be beneficial as an effective and inexpensive antifibrinolytic in first-time CABG patients.

Chronic Hepatitis C Virus Infection After Treatment for Pediatric Malignancy

Sera of 658 patients who had completed treatment for pediatric malignancy were analyzed by a second-generation enzyme-linked immunosorbent assay and recombinant immunoblot assay test to assess the prevalence of hepatitis C virus (HCV)-seropositivity. All HCV-seropositive patients underwent detailed clinical, laboratory, virologic, and histologic study to analyze the course of HCV infection. One hundred seventeen of the 658 patients (17.8%) were positive for HCV infection markers. Among the 117 anti-HCV+ patients, 41 (35%) were also positive for markers of hepatitis B virus infection with or without delta virus infection markers, 91 (77.8%) had previously received blood product transfusions, and 25 (21.4%) showed a normal alanine aminotransferase (ALT) level during the last 5-year follow-up (11 of them never had abnormal ALT levels). The remaining 92 patients showed ALT levels higher than the upper limit of normal range. Eighty-one of 117 (70%) anti-HCV+ patients were HCV-RNA+, with genotype 1b being present in most patients (54%). In univariate analysis, no risk factor for chronic liver disease was statistically significant. In this study, the prevalence of HCV infection was high in patients who were treated for a childhood malignancy. In about 20% of anti-HCV+ patients, routes other than blood transfusions are to be considered in the epidemiology of HCV infection. After a 14-year median follow-up, chronic liver disease of anti-HCV+ positive patients did not show progression to liver failure.

Chronic Hepatitis C Virus Infection After Treatment for Pediatric Malignancy

Sera of 658 patients who had completed treatment for pediatric malignancy were analyzed by a second-generation enzyme-linked immunosorbent assay and recombinant immunoblot assay test to assess the prevalence of hepatitis C virus (HCV)-seropositivity. All HCV-seropositive patients underwent detailed clinical, laboratory, virologic, and histologic study to analyze the course of HCV infection. One hundred seventeen of the 658 patients (17.8%) were positive for HCV infection markers. Among the 117 anti-HCV+ patients, 41 (35%) were also positive for markers of hepatitis B virus infection with or without delta virus infection markers, 91 (77.8%) had previously received blood product transfusions, and 25 (21.4%) showed a normal alanine aminotransferase (ALT) level during the last 5-year follow-up (11 of them never had abnormal ALT levels). The remaining 92 patients showed ALT levels higher than the upper limit of normal range. Eighty-one of 117 (70%) anti-HCV+ patients were HCV-RNA+, with genotype 1b being present in most patients (54%). In univariate analysis, no risk factor for chronic liver disease was statistically significant. In this study, the prevalence of HCV infection was high in patients who were treated for a childhood malignancy. In about 20% of anti-HCV+ patients, routes other than blood transfusions are to be considered in the epidemiology of HCV infection. After a 14-year median follow-up, chronic liver disease of anti-HCV+ positive patients did not show progression to liver failure.

History of posttransfusion hepatitis

The risk of hepatitis virus transmission from transfusions has declined dramatically from that of the 1940s when posttransfusion hepatitis (PTH) was first appreciated. Introduction of hepatitis B surface antigen screening and conversion to volunteer donors for whole-blood donations in the late 1960s and early 1970s led to substantial reduction in PTH cases. However, up to 10% of the recipients continued to develop PTH, most cases of which were attributed to an unknown non-A, non-B viral agent. Implementation of surrogate marker testing (i.e., alanine aminotransferase and anti-hepatitis B virus core antigen) for residual non-A, non-B hepatitis in the late 1980s reduced the per unit risk of PTH from 1 in 200 to about 1 in 400. Hepatitis C virus was discovered in 1989 and quickly was established as the causative agent of &gt;90% of non-A, non-B PTH. Introduction of progressively improved antibody assays in the early 1990s reduced the risk of PTH due to hepatitis C virus to about 1 in 100 000. Although additional hepatitis viruses exist (e.g., hepatitis G virus), these appear to be minor contributors to clinical PTH, which has been virtually eradicated.

How important is hepatitis C virus (HCV)-infection in persons with acute leukemia?

Hepatitis C virus (HCV)-infection is common in persons with leukemia. Blood transfusions are the typical source and HCV-related chronic hepatitis a common outcome. Development of HCV-infection and -related hepatitis raises important questions about subsequent leukemia treatment including the natural history of the infection and need for treatment modification. Although the natural history of HCV-infection and -related hepatitis in this setting is unknown, data from normal persons with HCV-infection suggest that short-term survival is not likely to be decreased in persons with leukemia and these complications. In contrast, long-term survival may decrease because of a high rate of chronic hepatitis, cirrhosis, and possibly hepatocellular carcinoma. There are no convincing data that HCV-infection or -related hepatitis or alterations in anti-leukemia drug dose or schedule prompted by abnormal liver function tests, alter leukemia outcome. Consequently, it is uncertain whether drug doses and/or schedule should be modified in persons with leukemia and HCV-infection or -related hepatitis. Short-term outcome of blood cell and bone marrow transplants is also unaffected by HCV-infection or -related hepatitis.

Evaluation of hepatitis C virus envelope proteins expressed in E. coli and insect cells for use as tools for antibody screening

BACKGROUND/METHODS

The two envelope proteins of hepatitis C virus, E1 and E2, were expressed in E. coli and, as secretory proteins, in Sf9 insect cells using recombinant baculoviruses. Co-infection of insect cells with E1 and E2-recombinant baculoviruses was performed, which has been shown to result in formation of E1-E2 dimers. All envelope proteins were purified by Ni2+-NTA chromatography and used for screening of serum samples in a HCV EIA assay. Serum samples of normal blood donors, chronically HCV-infected patients, a mixed titer panel and several seroconversion panels were screened and compared to test results with Cobas Core Anti-HCV EIA.

RESULTS

Screening of the sera of chronically HCV-infected patients (100% positive in Cobas Core Anti-HCV EIA) revealed 10-40% anti-E1 positive sera using different Sf9-expressed, glycosylated proteins and 93% using E. coli-expressed, non-glycosylated E1 protein. When the same sera were tested with different E2 proteins expressed in Sf9 cells and in E. coli, about 70-73% showed anti-E2 reactivity. When the proteins from Sf9 cells co-infected with E1- and E2-recombinant baculoviruses were tested, 70-80% of the same sera showed anti-envelope reactivity.

CONCLUSIONS

Testing of these patient antisera, and those from the well-characterized mixed titer panel BBI-PHV203, showed that recombinant E1 expressed in E. coli and co-expressed E1 and E2 proteins from Sf9 cells could be used as additional tools for anti-HCV antibody screening.

Liver transplantation after coronary artery bypass grafting

Twelve patients are described who had liver transplantation after coronary artery bypass grafting (CABG). The liver disease in most of the patients was a consequence of hepatitis C resulting from blood transfusions at the time of CABG.

Patients' willingness to pay for autologous blood donation

Most cost-effectiveness analyses of autologous blood donation show very small health benefits for a substantial increase in resource utilization. However, these analyses do not consider the psychological benefits of peace of mind to patients participating in the program. In order to quantitate these benefits, we employed contingent valuation methodology to measure the willingness of patients undergoing elective surgery, to pay for autologous blood donation. The internal consistency of patient responses was investigated through correlations of willingness-to-pay values with risk perceptions and patient characteristics. Two hundred and thirty-five patients completed the self-administered questionnaire which included demographic, willingness-to-pay and risk perception questions. Median population willingness to pay for autologous blood donation was approximately $900 per patient. In multivariate analysis, willingness to pay varied significantly with dread of allogenic transfusion, perceived risk of requiring a blood transfusion and income. Patients who participate in autologous blood donation programs value the procedure highly and state they are willing to pay significant amounts out of pocket to assure themselves of available autologous blood. Willingness to pay correlated significantly with factors expected to influence value decisions.