Transmission of human immunodeficiency virus (HIV) by blood transfusions screened as negative for HIV antibody

The infectious risks of transfusions in the United States: a decision-analytic approach

INTRODUCTION

The development of AIDS as a result of HIV transmission and of cirrhosis as a result of chronic non-A, non-B hepatitis are the greatest infectious risks associated with transfusion in the United States. The goal of this study is to provide explicit quantitative guidelines to determine when the risk of death from all causes associated with transfusion exceeds the risk associated with anemia.

METHODS

This study uses a decision-analytic model.

RESULTS

On the basis of reported transfusion complication rates and an independent worst-case calculation of the risk of AIDS and non-A, non-B hepatitis, transfusion with red blood cells should be recommended as long as each unit received reduces the patient's risk of dying from anemia by at least 1/1100.

DISCUSSION

Because of the relative safety of the blood supply as a result of universal screening and donor deferral, the overestimation in practice of fatal infectious complications, and the possible underestimation of the risk of anemia, undertransfusion has the potential to be as serious a problem in the United States as is overtransfusion. Although caution should be exercised not to undertransfuse when a patient has an appreciable risk of anemia-associated death, we must be wary not to overtransfuse for temporary relief of morbidity.

Prevention of transmission of HIV by organ and tissue transplantation. HIV testing protocol and a proposal for recommendations concerning donor selection

Human immunodeficiency virus (HIV) can be transmitted by solid organ and some forms of tissue transplantation. Although routine screening of organ and tissue donors for anti-HIV antibodies was implemented in most Western European countries and North America in 1985, several recent case reports indicate that a definite, albeit very small, risk of HIV transmission still remains. The screening tests that are currently used cannot rule out a false-negative test result occurring during the window period. Moreover, massive transfusion of the donor during the donor procedure may result in an undetectable anti-HIV antibody titer (by dilution of donor blood) that consequently leads to a false-negative test result. These risks of HIV transmission via transplantation and important issues in HIV testing are discussed in detail. Furthermore, several recommendations for the prevention of transmission and a protocol for HIV testing for both organ and tissue donation are presented. These may serve as intermediary guidelines until official ones, such as already exist for blood donation, are defined by the transplantation communities. The exclusion of donors whose behavior may place potential recipients at risk for HIV infection is essential. A thorough heteroanamnesis of the donor's next of kin during the donor procedure should provide sufficient information about donor history to enable a decision to be made in this respect. Special attention is given to the question of whether the existing donor selection criteria for blood donation should be applied in a similar way to organ donation since the strict application of selection criteria may limit the number of available donor organs.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of residual 4'-aminomethyl-4,5',8-trimethylpsoralen and mutagenicity testing following psoralen plus UVA treatment of platelet suspensions

Psoralens and UVA light have been used in the laboratory to study the inactivation of viruses that may be infrequently present in platelet concentrates that are prepared for transfusion. In order to evaluate safety aspects of the treatment of platelet suspensions with 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT), we have investigated the residual levels and mutagenic potential of AMT after UVA phototreatment. 4'-aminomethyl-4,5',8-trimethylpsoralen, at a final concentration of 40 micrograms/mL, was added to platelet suspensions which contained 16% plasma and a synthetic medium. Platelet suspensions containing AMT were irradiated with up to 7.2 J/cm2 UVA light under normal oxygen levels. Residual levels of AMT were determined by HPLC and a bioassay based on bacteriophage phi 6 inactivation. The photodestruction of AMT or its activity by UVA was characterized by a D37 value of 0.6 and 0.3 J/cm2 with HPLC or bioassay, respectively. At 2.4 J/cm2 UVA, which results in approximately 5 log10 inactivation of vesicular stomatitis virus (VSV) and retention of platelet in vitro properties, 12% (HPLC) to 9% (bioassay) AMT remained. Like other psoralens, AMT was found to bind to serum proteins as shown by ultrafiltration. Results are consistent with approximately 36% of the initial drug load binding primarily to serum albumin. It was determined using 3H-AMT that 9 to 18% of radioactivity was bound to platelets in the absence of irradiation. Similar fractions (13 to 18%) of AMT were bound to platelets after 3.6 J/cm2 UVA irradiation, and 8 to 10% of total AMT was associated with saline-washed irradiated platelets and is presumably tightly bound.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of HIV-1 by polymerase chain reaction and culture in seronegative intravenous drug users in an inner-city emergency department

STUDY BACKGROUND

After a health care worker's unprotected exposure to a patient's blood, the current recommendation is to obtain consent from the source for serologic testing for HIV. If the test is negative, no further follow-up of the exposed provider is usually indicated.

OBJECTIVE

To determine if patients testing negative for HIV-1 antibody on routine serology harbor occult HIV-1 infection.

DESIGN

Cross-sectional, identity-unlinked, patient-related data and blood sample procurement for HIV-1 infection.

SETTING

Inner-city university hospital emergency department with high HIV-1 seroprevalence among patients.

TYPE OF PARTICIPANTS

IV drug users not known to have HIV-1 infection.

MEASUREMENTS

Serum samples were analyzed for HIV-1 antibodies by enzyme immunoassay and Western blot. Peripheral mononuclear cells were analyzed for HIV-1 provirus by polymerase chain reaction and viral culture.

MAIN RESULTS

Of 131 patients, 36 (27.5%) were Western blot-confirmed seropositive for HIV-1. Of the 95 seronegative patients, six (6.3%) were polymerase chain reaction positive, and one of these was confirmed with culture. The negative predictive value of standard serology was 93.5% with polymerase chain reaction alone and 98.9% with concordant polymerase chain reaction and culture results.

CONCLUSION

There may be a significant number of ED patients in HIV-1 prevalent populations who have occult HIV-1 infection not detectable by serology at the time of a health care provider exposure. Although these data suggest that further prospective study is warranted to better quantify the frequency of this phenomenon, these preliminary data suggest that current Centers for Disease Control recommendations regarding provider exposures may need to be reappraised for certain situations.

Surgical issues in the management of the HIV-infected patient

As of 1992, approximately 1,000,000 Americans are infected with HIV. The natural history of the illness includes a relatively long latent period (about 10 years) between infection and development of AIDS. Surgeons are called on to participate in the management of these patients, usually for diagnostic biopsies, supportive measures, or intraabdominal events. Precautions and safe surgical practices will minimize the risk of HIV transmission from patient to surgeon (or surgeon to patient).

Is a hemoglobin of 10 g/dL required for surgery?

The "10/30" (hemoglobin/hematocrit) rule has long been recognized and accepted in the medical community as the threshold for transfusion in the perioperative setting. However, an increasing number of publications suggest there is no absolute threshold for transfusion, and that this decision should be based on an assessment of the overall clinical picture presented by the patient. This article reviews the risks associated with blood transfusions, and the data in humans and animals that describe the benefits of transfusion. Recommendations on the trigger for red cell transfusion are provided.

Silent HIV infection

The period of latency between infection by the human immunodeficiency virus type-1 (HIV-1) and the production of specific antibodies to viral antigens may be prolonged and, occasionally, may last for years. This condition of seronegative infection could represent a serious risk of viral transmission from subjects who are unaware of their status. However, whether these individuals are actually infectious, especially through body fluids, has not been clarified. We have performed a prospective study in 65 high-risk individuals seronegative for HIV-1 antibodies for a prolonged period of time. Twelve of them (18%) were shown to be carriers of HIV-1 proviral sequences by the polymerase chain reaction (PCR). The virus was isolated from mitogen-stimulated peripheral blood lymphocytes in five out of ten subjects tested since the first positive PCR. In two of them, virus could also be isolated from cell-free plasma, subsequently they remained seronegative during 10 months of follow-up. These data indicate that delayed seroconversions may be associated with productive infection, suggesting that mechanism(s) other than viral latency may be responsible for the absence of antibody responses to HIV-1 proteins. Furthermore, our findings suggest that prolonged seronegative individuals can transmit HIV infection through their body fluids.

Transfusion transmitted infection: viral and exotic diseases

Viral and other exotic diseases may be transmitted by blood transfusion. These infections include human immunodeficiency virus (HIV), hepatitis viruses (A, B, C, D and E), syphilis, malaria, retrovirus HTLV-1, and cytomegalovirus. Other more exotic diseases which may be transmitted by transfusion of blood or blood components include Chagas' disease (Trypanosomiasis cruzi), Lyme disease (Borrelia burgdorferi), and Jakob-Creutzfeldt disease. Screening procedures currently used in Australian blood banks minimise transfusion-transmitted infection. The risk of acquiring any infection in this manner may be less than 0.1%.

The donation cycle: a framework for the measurement and analysis of blood donor return behaviour

The donation cycle represents a new framework for the measurement of blood donor return behaviour. Because it is based on the interval between successive donation attempts, it is more efficient than previously reported methods and the resulting data can be analysed using the statistical techniques for interval data. To illustrate the merits of this quantitative approach to the study of blood donor behaviour, the donation cycle framework is used to analyse the interval between the first and second donation attempts in a random sample (n = 5,183) of type 0, whole blood donors from the Gulf Coast Regional Blood Center. Simple statistical tools such as the log-rank test are employed to describe and to evaluate relative differences in the return behaviour of Rh-negative and Rh-positive donors. The analysis indicates that Rh-negative donors are significantly (p < 0.001) more likely than Rh-positive donors to attempt to donate on a second occasion. Kaplan-Meier estimates of the survival function of these first-time donors reveal marked elevations in the rate of return exactly 52 weeks after the initial donation. The donation cycle paradigm provides transfusion researchers with quantitative tools which are essential for designing statistically efficient, prospective intervention studies. By using the knowledge which such studies could provide, blood banks might be better able to manage donor return behaviour and thereby the safety of the blood supply.

Safety of the blood supply

This is a review of events when the medical community realized that AIDS was an infectious disease which might be transmitted by blood transfusions and the response by the various organizations and agencies to curb the potential spread of HIV via blood products. It became possible through a number of approaches to make the blood supply safe so that today the likelihood of transmission of HIV by blood transfusion is extremely unlikely.

Regional transfusion centre preoperative autologous blood donation programme: the first two years

OBJECTIVE

To assess the efficacy of a regional autologous blood donation programme.

DESIGN

Clinical and laboratory data were collected and stored prospectively. Transfusion data were collected retrospectively from hospital blood bank records.

SETTING

Northern Region Blood Transfusion Service and 14 hospitals within the Northern Regional Health Authority.

SUBJECTS

505 patients referred for autologous blood donation before elective surgery.

MAIN OUTCOME MEASURES

Patient eligibility, adverse events from donation, autologous blood units provided, and autologous and allogeneic blood units transfused within 10 days of operation.

RESULTS

Of 505 patients referred, 354 donated at least one unit. 78 of 151 referred patients who did not donate were excluded at the autologous clinic, mostly because of anaemia or ischaemic heart disease. In 73 cases the patient, general practitioner, or hospital consultant decided against donation. 363 autologous procedures were undertaken. In 213 (59%) cases all requested units were provided. The most common reasons for incomplete provision were late referral or anaemia. Adverse events accompanied 24 of 928 donations (2.6%). Transfusion data were obtained for 357 of the 363 procedures. 281 donors were transfused; autologous blood only was given to 225, autologous and allogeneic blood was given to 52, and allogeneic blood only was given to four. 648 of 902 (72%) units of autologous blood were transfused. Complete provision of requested autologous units was followed by allogeneic transfusion in 12 of 208 procedures (5.8%). Incomplete provision was followed by allogeneic transfusion in 44 of 149 procedures (30%).

CONCLUSIONS

This study shows the feasibility of a regional autologous transfusion programme. Autologous donors only infrequently received allogeneic transfusion. Patients should be appropriately selected and referred early.

Perioperative haemotherapy: II. Risks and complications of blood transfusion

Major life-threatening complications following blood transfusion are rare and human error remains an important aetiological factor in many. The infectious risk from blood transfusion is predominantly hepatitis, and non-A, non-B and hepatitis C (HCV) are the most common subtypes noted. The risk of post-transfusion hepatitis (PTH) appears to be decreasing and this is attributed to both deferral of high-risk donors and more aggressive screening of donated blood. Screening for HCV is expected to decrease this risk further. The risk of HIV transmission following blood transfusion is negligibly small. There are data to suggest that perioperative blood transfusion results in suppression of the recipient's immune system. Earlier recurrence of cancer and an increased incidence of postoperative infection have been associated with perioperative blood transfusion although the evidence is not persuasive. Microaggregate blood filters are not recommended for routine blood transfusion but do have a role in the prophylaxis of non-haemolytic febrile reactions caused by platelet and granulocyte debris in the donor blood. Patients should be advised when there is likely to be a requirement for perioperative blood transfusion and informed consent for transfusion should be obtained.

Current procedures for banking allograft human bone

The demand for bone and soft tissues for surgical usage has increased rapidly as the efficacy and safety of these materials has been demonstrated. Advances in technology and procedures used to prepare the tissues have also grown in sophistication and remain a dynamic area. How tissue banks screen donors and prepare allografts impacts on the risks and benefits of these materials. Surgeons should understand how tissue banks supplying their graft materials work and have confidence in this treatment option. They will then be prepared to educate their patients to help them make informed decisions concerning allograft usage.

Effects of acute isovolemic hemodilution and anesthesia on regional function in left ventricular myocardium with compromised coronary blood flow

The effects of progressive, isovolemic hemodilution using Dextran 70 and the effect of halothane (0.7, 0.9, 1.1, and 1.3% end-tidal, administered randomly at each level of hemodilution) on global cardiovascular and regional LV contractile functions were investigated in 24 dogs with induced critical constriction of the left anterior descending coronary artery (LAD). Two additional groups of six dogs each (with and without LAD stenosis) not undergoing hemodilution served as time controls. Regional LV contractile function was assessed by sonomicrometry in the flow-compromised apical LAD territory, as well as in three non-compromised LV areas supplied by the left circumflex coronary artery. Regional myocardial function was found to be stable throughout the study period of 4-5 h in both time control groups. Mean arterial and coronary perfusion pressures as well as LV dP/dtmin decreased (P < 0.01) during hemodilution. LV dP/dtmax remained unchanged, and heart rate and LVEDP increased slightly (P < 0.05). Systolic shortening (SS) in the LAD territory was unchanged at a hematocrit (HCT) of 33.5 +/- 0.3% (mean +/- s.e. mean), and decreased marginally at an HCT of 24.2 +/- 0.1% (SS of 17.4 +/- 1.0% as compared to 20.2 +/- 1.6% at critical constriction (CC), P < 0.05). No increase in post-systolic shortening (PSS) occurred in the compromised area. Severe LAD dysfunction was observed in the LAD territory at an HCT of 14.9 +/- 0.1%, as systolic shortening decreased (11.8 +/- 1.1%, P < 0.01 vs CC) and PSS increased (31.2 +/- 3.4%, P < 0.01 vs CC). The effects of hemodilution on global cardiovascular and regional myocardial functions were unaffected by halothane.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS: Part I

Acquired immunodeficiency syndrome (AIDS) is caused by infection with a pathogenic human retrovirus known as human immunodeficiency virus (HIV). Approximately 1 million people are currently infected with HIV in the United States, with 8 to 10 million infected individuals worldwide. The virus is transmitted predominantly through genital sexual contact, although orogenital spread has been rarely reported. Heterosexual transmission has been most common in the Third World, whereas male homosexual transmission has predominated in the United States and western Europe. Transmission through homosexual contact has been steadily declining over the past 5 years as transmission through illicit intravenous drug use and promiscuous unprotected heterosexual activity has increased. Sexually transmitted diseases that cause inflammatory or ulcerative lesions of the genital tract act as important cofactors in increasing the risk of transmission through sexual contact. Perinatal transmission of HIV occurs in approximately 30% of infants born to infected mothers. Transmission to infants through breast-feeding has also been documented. Health care workers have been infected with HIV through accidental high-risk percutaneous or mucous membrane exposures, albeit at a low transmission rate of 0.3%. Infection of patients by infected health care professionals is a rare event, having been reported only once in 10 years of the epidemic. Infection with HIV results in a chronic lifelong infection. The major targets for HIV are CD4+ T-helper lymphocytes and cells of monocyte/macrophage lineage. Infection of the T-helper lymphocyte ultimately results in the death of the cell. Over time (measured in years), a progressive destruction of the T-helper lymphocyte population occurs, which results in profound immune suppression. Infection of monocytes/macrophages is not cidal, but these cells do have functional alterations as a result of the infection, which may contribute to the immune deficiency. In addition, chronically infected tissue macrophages may act as an important reservoir for HIV, particularly in the central nervous system. Infection of the T-helper lymphocytes and monocytes/macrophages is mediated through attachment of HIV through a specific binding interaction between CD4 expressed in the plasma membrane of these cells and a surface glycoprotein on the virus, gp120. Once the virus nucleocapsid (core particle) enters the cytoplasm of the target cell, the viral RNA genome is reverse transcribed by a reverse transcriptase enzyme into proviral DNA. This proviral DNA migrates into the nucleus where it integrates into the host cellular genome, which results in a chronically infected cell.(ABSTRACT TRUNCATED AT 400 WORDS)

Use of predeposit autologous blood and intraoperative autotransfusion in urologic cancer surgery

A total of 20 patients underwent major urologic cancer surgery with the combined use of predeposit autologous blood and intraoperative autotransfusion with the Haemonetics Cell Saver. The estimated blood loss ranged from 400 to 2,000 mL (mean 1,208 mL). Total transfusion requirements for the 20 patients were 85.5 units of which 82.5 (96%) were autologous. Predeposit autologous blood accounted for 53 percent, intraoperative autotransfusion blood 43 percent, and homologous blood 4 percent of the total transfusion requirements. Of the 20 patients in the study, only 1 received homologous blood. There were no complications related to either modality of autotransfusion. Our data suggest that using the combined modalities of predeposit autologous blood donation and intraoperative autotransfusion, major urologic cancer surgery can be performed without homologous blood in most cases.

Risk of HIV infection from transfusion with blood negative for HIV antibody in a west African city

OBJECTIVE

To estimate the risk of infection with HIV (HIV 1 or HIV 2, or both) from transfusion of a screened unit of blood in a high prevalence area in west Africa.

DESIGN

Retrospective cohort study for January-July 1991.

SETTING

National Blood Transfusion Centre, Abidjan, Côte d'Ivoire.

SUBJECTS

Repeat donors (5831 units of blood) and first time donors (5076 units) in the first five months of 1991.

MAIN OUTCOME MEASURES

Prevalence and estimated incidence of HIV infection in repeat and first time donors; estimated rate of potentially infected, HIV antibody negative units; and rate of (false negative) potentially infected units assuming a laboratory test sensitivity of 99%.

RESULTS

Overall HIV prevalence was 11.0% in first time donors and 2.1% in repeat donors. In the first seven months of 1991, 29 HIV antibody positive (27 HIV 1, 1 HIV 2, 1 dually reactive) donors with a seronegative unit of blood earlier in the year were identified; 26 had donated blood eight weeks or less before their estimated dates of seroconversion and may have been infectious (minimum rate 26/5831 (4.5/1000 potentially infected units)). Estimated incidence of infection in repeat donors was 1.2-2.5%. Laboratory test insensitivity would result in an estimated 1.1/1000 false negative units from first time donors and 0.2/1000 units from regular donors. The overall rate of potentially infected units (all donors, seroconversions, and errors) was estimated at 5.4-10.6/1000.

CONCLUSIONS

The risk of HIV infection from a single unit of blood remains substantial (5.4-10.6/1000 units). To prevent infection from blood transfusion in areas of high incidence and prevalence of HIV all but absolutely essential transfusions should be avoided, and donors with low incidence of HIV infection should be selected.

Intraoperative autotransfusion in hip arthroplasty. A retrospective study of 214 cases with matched controls

The transfusion requirements in 214 patients who received intraoperatively collected autologous blood during total hip arthroplasty (Study Group) were compared with 214 age- and sex-matched controls who received homologous bank blood (Control Group). There were 132 patients with primary operations, 27 bilateral, and 55 revisions in each group. In the Study Group, there was a reduction in the amount of homologous blood transfusion, intraoperatively as well as totally, and also in postoperative blood loss in all three operation subsets. The Study and Control Groups were equal in pre- and postoperative hemoglobin and hematocrit values.

Use of sulphonated probes for detecting human immunodeficiency virus-1 transcripts by in situ hybridization

A detailed procedure is described that allows detection of the presence of human immunodeficiency virus-1 (HIV-1) transcripts within both acetone-fixed tissues and peripheral blood mononuclear cells. This assay uses cDNA probes labelled by a non-isotopic procedure that results in the modification of cytosine residues through covalent linkage to a sulphone group. In situ hybridized probe is then detected by an alkaline phosphatase-conjugated antibody specifically directed against the sulphone hapten. This procedure is specific, rapid and safe and can be applied in the research as well as in the clinical pathology settings.

Transfusion therapy in elective total hip arthroplasty

A retrospective audit of transfusion practice in 150 consecutive elective primary total hip arthroplasties was undertaken, to examine blood usage and to determine the potential for reduction in its use. Predetermined criteria were used to measure unnecessary transfusions. Transfusion was considered unnecessary if the discharge haematocrit exceeded 36%, or if patients who lost less than 30% of their estimated blood volume, were transfused. Using these criteria, overtransfusion occurred in 42-45% patients. The intra-operative blood transfused correlated well with intra-operative blood lost. All other variables showed no significant correlation with both intra-operative and post-operative blood transfused. Females lost less and were transfused significantly more than males. The study corroborates previous reports of blood overuse. These results suggest that adopting standards of practice to measure and to monitor transfusion practice (quality assurance programmes) would be a worthwhile objective.

Occupational exposure to human immunodeficiency virus and hepatitis B virus: a comparative analysis of risk

OBJECTIVE

To estimate the occupational risk from infection with the human immunodeficiency virus (HIV) in terms of loss of (quality-adjusted) life expectancy, and to compare that risk to those posed by other hazards faced by health care workers.

DESIGN

Decision-analytic model.

RESULTS

For a 30-year-old female health care worker (unvaccinated for hepatitis B virus [HBV]), the loss of life expectancy from a needlestick from a symptomatic HIV-positive (HIV+) patient is 39 days (range, 17 to 93 days), as compared with a loss of 17 days from a needlestick from a patient who is hepatitis-B-surface-antigen-positive (HBsAg+), and 38 days from a needlestick from a patient who is hepatitis-B-e-antigen-positive (HBeAg+). When morbidity is included in the analysis of risk (through calculation of the quality-adjusted loss of life expectancy), the risk from both HBV and HIV increases. The quality-adjusted loss of life expectancy due to a needlestick exposure from a symptomatic HIV+ patient is 45 days (range, 20 to 108 days), as compared with a quality-adjusted loss of life expectancy of 48 days from a needlestick from an HBsAg+ patient, and 109 days from a needlestick from a patient who is known to be HBeAg+. By comparison, a cross-country automobile trip is associated with a loss of life expectancy of approximately 1 day. The 45- to 50-day loss of quality-adjusted life expectancy from percutaneous exposures to HIV and HBV is approximately the same magnitude as the gain in life expectancy from 10 years of annual screening for breast cancer with mammography and physical examination.

CONCLUSIONS

The risk associated with percutaneous exposures to symptomatic HIV+ patients is comparable to other risks that health care workers have faced knowingly and have accepted in the recent past. However, the loss of quality-adjusted life expectancy associated with a needlestick exposure is significant. Identification of cost-effective methods that increase the safety of medical personnel but also ensure full access to high-quality care for HIV+ patients should be a high priority.

Transmission of human immunodeficiency virus type 1 from a seronegative organ and tissue donor

BACKGROUND

Since 1985, donors of organs or tissues for transplantation in the United States have been screened for human immunodeficiency virus type 1 (HIV-1), and more than 60,000 organs and 1 million tissues have been transplanted. We describe a case of transmission of HIV-1 by transplantation of organs and tissues procured between the time the donor became infected and the appearance of antibodies. The donor was a 22-year-old man who died 32 hours after a gunshot wound; he had no known risk factors for HIV-1 infection and was seronegative.

METHODS

We reviewed the processing and distribution of all the transplanted organs and tissues, reviewed the medical histories of the donor and HIV-1-infected recipients, tested stored donor lymphocytes for HIV-1 by viral culture and the polymerase chain reaction, and tested stored serum samples from four organ recipients for HIV-1 antigen and antibody.

RESULTS

HIV-1 was detected in cultured lymphocytes from the donor. Of 58 tissues and organs obtained from the donor, 52 could be accounted for by the hospitals that received them. Of the 48 identified recipients, 41 were tested for HIV-1 antibody. All four recipients of organs and all three recipients of unprocessed fresh-frozen bone were infected with HIV-1. However, 34 recipients of other tissues--2 receiving corneas, 3 receiving lyophilized soft tissue, 25 receiving ethanol-treated bone, 3 receiving dura mater treated with gamma radiation, and 1 receiving marrow-evacuated, fresh-frozen bone--tested negative for HIV-1 antibody. Despite immunosuppressive chemotherapy, HIV-1 antibody appeared between 26 and 54 days after transplantation in the three organ recipients who survived more than four weeks.

CONCLUSIONS

Although rare, transmission of HIV-1 by seronegative organ and tissue donors can occur. Improvements in the methods used to screen donors for HIV-1, advances in techniques of virus inactivation, prompt reporting of HIV infection in recipients, and accurate accounting of distributed allografts would help to reduce further this already exceedingly low risk.

Transmission of HIV by transfusion of HIV-screened blood: the value of a national register. The 'Recipients' Study Group of the French Society of Blood Transfusion

A National Register of transfusion-transmitted infections was opened by the French Society of Blood Transfusion on 1 October, 1986. Out of 54 initially reported cases of HIV-infection, allegedly transmitted by blood components, further investigation could be completed in 33 cases. The transfusional origin of contamination was considered as established or probable in 28/33 cases, either because a potentially infectious unit was identified among those transfused to the recipient (23/28), or because the recipient was known to be seronegative before transfusion (5/28), or both (10/28). In 5/33 cases transfusion was considered as presumably responsible for contamination because no other risk factor was found in the recipient. Among the 33 documented cases of HIV-transmission by screened blood, 29 (88%) occurred between 1985 and 1987, and four (12%) during 1988. Out of 19 implicated donors later found seropositive, 16 belonged to a high-risk group for HIV-infection. The majority of HIV-infections occurred as a consequence of blood donation in the window period between contamination and the appearance of detectable antibodies in the donor's serum (11/19). In three instances, however, human and operational errors led to the release of seropositive units. We conclude that the main value of this Register is to provide a potential trend-indicator of transfusion-related infectious risks, to allow objective documentation of reported cases and to contribute to the improvement of blood transfusion practice.

Blood-borne Infections Associated with Transfusion

The epidemic of acquired immunodeficiency syndrome (AIDS) and the realization that transmission of human immunodeficiency virus is caused by homologous blood transfusion have changed the way physicians and their patients view the safety of hemotherapy. Considering that nearly four million patients receive the lifesaving benefits of blood transfusions every year in the United States, we need to recognize and reduce the inherent biological complications of this therapy. Currently, a major concern is the transmission of blood-borne infectious agents and the establishment of persistent infection in transfusion recipients, which is apparently facilitated by suppression of the recipient's hematopoietic and immune systems. Education of blood donors, patients, and attending physicians regarding infectious complications of transfusion is essential and remains the most effective procedure for making rational decisions. Before giving blood transfusions, astute physicians should calculate a risk/benefit ratio and communicate it to the patient or family. Potential recipients of transfusions can be assured that the blood supply is safer now than at any time in the past, although there is still a very small risk for the transmission of infectious agents that cause chronic diseases, such as hepatitis, AIDS, neuropathies, and leukemias. It is essential that everyone understands that the goal of a zero-risk blood supply is not attainable. Recent developments in molecular biology and biotechnology, however, provide opportunities for further reduction of infectious complications of blood transfusions.

Interviews with anti-HIV-positive individuals detected through the systematic screening of blood donations: consequences on predonation medical interview

This study is based upon interviews with 74 individuals found to be human immunodeficiency virus (HIV)-seropositive through the screening of blood donations between January 1988 and December 1990. The donation history and the risk factor of HIV infection were established. Questions about the use of blood donation as a diagnostic test and on the notion of a predonation medical interview evoking the risk factor were asked. The majority of the individuals had a risk factor of HIV infection and had given their blood for serological testing. This data can help to adapt the predonation medical interview to the present epidemiological context of HIV infection. The improvement of this interview will contribute to the decrease of the residual transfusional risk of HIV infection.

Clinical risks of thrombolytic therapy

Understanding the clinical risks of intravenous thrombolytic therapy is critical to appropriate patient selection. The major risks can be classified into 5 major categories: intracranial hemorrhage, systemic hemorrhage, immunologic complications, hypotension, and myocardial rupture. Although theoretical concern exists about thromboembolic complications, they rarely occur. Although cardiac rhythm disturbances are somewhat more likely to occur at the time of reperfusion, the clinical significance of "reperfusion arrhythmias" is minimal. Intracranial hemorrhage, the most devastating complication, occurs in 0.2-1% of patients treated with thrombolytic therapy. Factors associated with incremental risk are now being identified from large clinical trials. Systemic hemorrhage is uncommon in patients without major vascular punctures and seldom leads to serious adverse outcomes. Immunologic complications--including anaphylaxis, which is rare, and immune complex disease, which is more common--occur only with streptokinase or agents with a streptokinase moiety, including anistreplase (anisoylated plasminogen--streptokinase activator complex, APSAC). Hypotension, which can be managed easily in most patients, is also observed much more frequently with streptokinase and anistreplase. Myocardial rupture is increasingly being recognized as a possible complication of late thrombolysis. A proper perspective on clinical risk can only be gained in the context of potential benefit of therapy. In many cases individual patients considered to be at highest risk for complications also stand to gain the most from treatment. Many of the questions raised by currently available data about bleeding risk are being addressed in the ongoing Global Utilization of t-PA and Streptokinase (GUSTO) Trial. A paradigm for considering this decision making problem is presented.

The provision of safe blood--policy issues in the prevention of human immunodeficiency virus transmission

The AIDS epidemic has focused attention on the constraints and deficiencies present in many blood transfusion services in the developing world. We discuss a variety of options for reducing transfusion-related HIV transmission, and suggest how new transfusion strategies may be implemented. We show that a transfusion service cannot rely solely on the screening of donor blood for anti-HIV antibodies and that a more comprehensive approach is needed. Important components of this approach include donor selection and improved clinical practice, in which blood and blood products are prescribed only when really necessary.

The risks of blood transfusion: the relative influence of acquired immunodeficiency syndrome and non-A, non-B hepatitis

PURPOSE

The acquired immunodeficiency syndrome epidemic has greatly increased concern about the risk of blood transfusion. Many transfusions are now autologous, and when these are not available, both physicians and patients are more likely to question the advisability of transfusion. We evaluate the risk of preoperative blood transfusion and the contribution of human immunodeficiency virus (HIV) infection to that risk.

METHODS

We used decision analysis to characterize the risk associated with HIV infection in days of life lost. The contributions to risk of acute transfusion reaction, hepatitis B, and non-A, non-B hepatitis are also estimated. Sensitivity analyses show the implications for transfusion risk of recent information about HIV infection in the blood supply and a new test for hepatitis C.

RESULTS

The analysis shows that the contribution of HIV infection to the risk of death from transfusion, expressed in days of life expectancy lost, has become extremely small over the last several years. Currently, HIV infection accounts for less than 1% of the risk of death, while non-A, non-B hepatitis accounts for 97% to 98%. Further reductions in the risk of HIV infection, even to zero, will make relatively little difference in the safety of transfusion. The analysis also shows that the remaining risk from transfusion should decrease sharply, by more than two thirds, with the adoption of the test for hepatitis C.

CONCLUSIONS

Efforts to improve the safety of blood should focus on reducing the risk of non-A, non-B hepatitis. The remaining risk of HIV infection is very small.

Co-amplification of specific sequences of HCV and HIV-1 genomes by using the polymerase chain reaction assay: a potential tool for the simultaneous detection of HCV and HIV-1

A rapid and simple method using the polymerase chain reaction (PCR) was devised for the co-amplification and simultaneous detection of hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) specific sequences in the same serum sample. Genomic RNA was extracted from 13 blood donor sera that were reactive in ELISA for both anti-HCV and anti-HIV-1. The extracted RNA was reverse transcribed into cDNA and amplified using nested primer pairs (SN01 and SN04; SN02 and SN03) based on the HCV prototype sequence of clones 37b and 81, and SK 38/39 for HIV-1 simultaneously. PCR products were analyzed by liquid hybridization or Southern blot hybridization with 32P end-labeled oligonucleotide probes from the regions between the primer pairs, excluding the primer sequences. HCV-RNA was detected in all 13 (100%) samples tested; HIV-RNA was detected in 11 (85%) samples. The ability to co-amplify specific sequences from two different viral genomes in the same reaction mixture offers the possibility of simultaneous detection and diagnosis of more than one viral agent in serum samples of infected individuals.

How well are hospitals preventing iatrogenic HIV? A study of the appropriateness of blood transfusions in three hospitals in the Ashanti region, Ghana

A study on the appropriateness of blood and blood product transfusions took place in three hospitals over a 3-week period in July/August 1990 in the Ashanti region of Ghana. Clinical records of all blood transfusion recipients within the period were examined for the appropriateness of the transfusions based on preset criteria. Nearly 1 in 5 (17%) of all blood transfusion episodes in the hospitals were avoidable according to these criteria. Surgical practices were associated, perhaps habitually, with many more avoidable blood transfusions than non-surgical medical practices. The need to minimize the use of transfusion therapy is reemphasized since human immunodeficiency virus screening is imperfect. There is the need for hospitals to develop reasonable, practical guidelines for transfusions in all departments.

Human immunodeficiency virus infection elicits early antibody not detected by standard tests: implications for diagnostics and viral immunology

The FDA-approved tests for diagnosis of HIV exposure depend on detection of specific antibody in serum. HIV infection is missed in some individuals because they score seronegative by the standard clinical EIA and Western blot assays. This apparent immunological "silent" period following infection may last for months and has been reported to be as long as 3 years in rare cases. Is there truly a lack of an immune response or is there a more subtle, narrowly focused antibody response in these HIV-infected individuals which is not detected by the current tests? Using a nondenaturing serological assay (immunofluorescence of live infected T-cells), we found that each of four infected individuals "seronegative" by the standard tests did possess antibody against native HIV proteins expressed on infected cells. These antibodies reacting with native HIV antigenic epitopes were of the IgG isotype, they cross-reacted with many, but not all, of seven random HIV-1 isolates, and one of the sera immunoprecipitated HIV gp160 from NP-40-solubilized infected cells. These results show that seronegative, high-risk, infected individuals can actually be seropositive and that different types of assays using native antigenic epitopes may be required for screening. Implementation of these findings thus may decrease HIV transmission. These results also highlight the importance of protein conformation for many natural viral antigenic epitopes.