Survey of transfusion-associated graft-versus-host disease in immunocompetent recipients

Amotosalen/UVA treatment inactivates T cells more effectively than the recommended gamma dose for prevention of transfusion-associated graft-versus-host disease

INTRODUCTION

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare complication after transfusion of components containing viable donor T cells. Gamma irradiation with doses that stop T-cell proliferation is the predominant method to prevent TA-GVHD. Treatment with pathogen inactivation methodologies has been found to also be effective against proliferating white blood cells, including T cells. In this study, T-cell inactivation was compared, between amotosalen/ultraviolet A (UVA) treatment and gamma-irradiation (2500 cGy), using a sensitive limiting dilution assay (LDA) with an enhanced dynamic range.

METHODS AND MATERIALS

Matched plasma units (N = 8), contaminated with 1 × 10⁶ peripheral blood mononuclear cells (PBMCs) per mL, were either treated with amotosalen/UVA or gamma irradiation, or retained as untreated control. Posttreatment, cells were cultured under standardized conditions. T-cell proliferation was determined by the incorporation of ³ H-thymidine and correlated with microscopic detection.

RESULTS

Range-finding experiments showed that after gamma irradiation (2500 cGy), significant T-cell proliferation could be observed at a 1 × 10⁷ cell culture density, some proliferation at 1 × 10⁶ , and none at 1 × 10⁵ cells/well. Based on these facts, a quantitative comparison was carried out between amotosalen/UVA at the highest challenge of 1 × 10⁷ PBMCs/well, and gamma irradiation at 1 × 10⁶ and 1 × 10⁵ PBMCs/well. Complete inactivation of the T cells after amotosalen/UVA treatment was observed, equivalent to greater than 6.2 log inactivation. Complete inactivation of the T cells was also observed after gamma irradiation when 1 × 10⁵ PBMCs/well were cultured (>4.2 log inactivation). Proliferation was observed when 1 × 10⁶ PBMCs/well were cultured (≤5.2 log inactivation) after gamma irradiation.

CONCLUSION

Amotosalen/UVA treatment more effectively inactivates T cells than the current standard of gamma irradiation (2500 cGy) for the prevention of TA-GVHD.

Transfusion Reactions

Transfusion reactions are common occurrences, and clinicians who order or transfuse blood components need to be able to recognize adverse sequelae of transfusion. The differential diagnosis of any untoward clinical event should always consider adverse sequelae of transfusion, even when transfusion occurred weeks earlier. There is no pathognomonic sign or symptom that differentiates a transfusion reaction from other potential medical problems, so vigilance is required during and after transfusion when a patient presents with a change in clinical status. This review covers the presentation, mechanisms, and management of transfusion reactions that are commonly encountered, and those that can be life-threatening.

Survey of Irradiation Practice for the Prevention of Transfusion-Associated Graft-versus-Host Disease

Context.—Transfusion-associated graft-versus-host disease is a rare, often fatal complication of cellular blood product transfusion. The requirement that at-risk groups receive irradiated products reduces the incidence of transfusion-associated graft-versus-host disease. A comprehensive survey of irradiation practices has not been performed since 1989; meanwhile, new indications for irradiation have emerged.

Objective.—To assess current irradiation practices at College of American Pathologists member institutions. Changes in irradiation practice indicated by comparing results of a survey of irradiation practices in 1989 with those of a survey performed in 2014 may reveal how the field has developed and what areas (if any) remain to be improved.

Design.—A supplemental College of American Pathologists survey was sent out with questions regarding irradiation practices for specific conditions and circumstances. The questions included conditions for which irradiation is generally considered required for the prevention of transfusion-associated graft-versus-host disease as well as those not considered to be a special risk.

Results.—An average of 2100 organizations responded to each question regarding their irradiation practices. Irradiation for transfusion from blood relatives, human leukocyte antigen–matched products, preterm infants, and Hodgkin disease were the most common indications cited. A few organizations had universal irradiation, whereas others irradiated products by floor/unit or by service.

Conclusions.—For some at-risk populations irradiation of cellular blood products is more common than in 1989, whereas for others this practice has been reduced. Although gains have been made since the last national survey of irradiation practices, work remains to eliminate the possibility of transfusion-associated graft-versus-host disease from known at-risk populations.

Red Blood Cell Transfusion

Blood is classified as a drug and transfusion is one of the most commonly performed procedures in the USA. General knowledge of blood manufacturing, shelf life and storage media, common component modifications, blood types, and product compatibility allows the clinician to better communicate their needs and to understand what options may be available when ordering blood products. All transfusions offer benefits, and the clinician must comprehend the possible adverse events, especially those related to TRALI, which continues to be the most common cause of transfusion-related death reported to FDA, with TACO as the second most-commonly reported event. Transfusing in the setting of hemorrhagic blood loss adds additional challenges regarding volume overload, coagulopathy, and optimum transfusion ratios of red cells, plasma, platelets, and cryoprecipitate. The information imparted in this chapter will help equip the clinician with the knowledge needed to make the best decisions for patients requiring blood products, especially injured patients.

A systematic review of transfusion-associated graft-versus-host disease

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare complication of blood transfusion. The clinicolaboratory features of TA-GVHD and the relative contributions of recipient and component factors remain poorly understood. We conducted a systematic review of TA-GVHD reports. The HLA relationship between donor and recipient was classified as D = 0 when no donor antigens were foreign to the recipient vs D ≥ 1 when ≥1 donor antigen disparity occurred. We identified 348 unique cases. Criteria for component irradiation were met in 48.9% of cases (34.5% immune-compromised, 14.4% related-donor), although nonirradiated components were transfused in the vast majority of these (97.6%). Components were typically whole blood and red cells. When reported, component storage duration was ≤10 days in 94%, and 23 (6.6%) were leukoreduced (10 bedside, 2 prestorage, and 11 unknown). Among 84 cases with HLA data available, the category of D = 0 was present in 60 patients (71%) at either HLA class I or II loci and was more common among recipients without traditional indications for component irradiation. These data challenge the historic emphasis on host immune defects in the pathogenesis of TA-GVHD. The dominant mechanism of TA-GVHD in both immunocompetent and compromised hosts is exposure to viable donor lymphocytes not recognized as foreign by, but able to respond against, the recipient.

Prevention of transfusion-associated graft-versus-host disease by irradiation: technical aspect of a new ferrous sulphate dosimetric system

Irradiation of whole blood and blood components before transfusion is currently the only accepted method to prevent Transfusion-Associated Graft-Versus-Host-Disease (TA-GVHD). However, choosing the appropriate technique to determine the dosimetric parameters associated with blood irradiation remains an issue. We propose a dosimetric system based on the standard Fricke Xylenol Gel (FXG) dosimeter and an appropriate phantom. The modified dosimeter was previously calibrated using a ⁶⁰Co teletherapy unit and its validation was accomplished with a ¹³⁷Cs blood irradiator. An ionization chamber, standard FXG, radiochromic film and thermoluminescent dosimeters (TLDs) were used as reference dosimeters to determine the dose response and dose rate of the ⁶⁰Co unit. The dose distributions in a blood irradiator were determined with the modified FXG, the radiochromic film, and measurements by TLD dosimeters. A linear response for absorbed doses up to 54 Gy was obtained with our system. Additionally, the dose rate uncertainties carried out with gel dosimetry were lower than 5% and differences lower than 4% were noted when the absorbed dose responses were compared with ionization chamber, film and TLDs.

Evaluation of transfusion pyrexia: a review of differential diagnosis and management

Background/purpose. Transfusion pyrexia (fever) is an important clinical sign/symptom occurring either as an isolated event or as part of a constellation of signs and symptoms in relation to blood transfusion. It is an important cause of morbidity and may be an important sign of life-threatening complications of blood transfusion. Pyrexia is often a reason for the discontinuation of a blood transfusion episode, and adequate evaluation remains a challenge for clinicians. The decision to stop a blood transfusion episode on account of fever is often a difficult one. This paper reviews the differential diagnosis of transfusion pyrexia (TP), the pathogenesis as well as current management measures. Study selection and data source. Literature sources include medical texts, journals, dissertations, and internet-based electronic materials Results and conclusion. Adequate evaluation of pyrexia accompanying blood transfusion remains a challenge for clinicians. An algorithm to assist the clinician in the evaluation of fever occurring in a blood transfusion recipient is developed and presented. Continuous medical education is necessary for clinicians towards improved patient care in transfusion medicine.

Transfusion associated graft versus host disease following whole blood transfusion from an unrelated donor in an immunocompetent patient

Graft-versus-host disease (GVHD) is a well-known complication of allogeneic bone marrow transplantation. Transfusion associated graft-versus-host disease (TA-GVHD) is much less common and nearly uniformly fatal complication of blood transfusion. The risk factors underlying the development of TA- GVHD are incompletely defined, but it is commonly seen in individuals with congenital or acquired immunodeficiency, transfusions from blood relatives, intrauterine transfusions and HLA-matched platelet transfusions. Diagnosis of TA-GVHD may be difficult at a time due to rarity in occurrence and overlapping clinical features with various infections and drug reactions. We describe a case of transfusion-associated GVHD that occurred after transfusion of whole blood from unrelated donor in an immunocompetent patient.

Comparison of platelet transfusion as fresh whole blood versus apheresis platelets for massively transfused combat trauma patients (CME)

BACKGROUND

At major combat hospitals, the military is able to provide blood products to include apheresis platelets (aPLT), but also has extensive experience using fresh whole blood (FWB). In massively transfused trauma patients, we compared outcomes of patients receiving FWB to those receiving aPLT.

STUDY DESIGN AND METHODS

This study was a retrospective review of casualties at the military hospital in Baghdad, Iraq, between January 2004 and December 2006. Patients requiring massive transfusion (≥10 units in 24 hr) were divided into two groups: those receiving FWB (n = 85) or aPLT (n = 284) during their resuscitation. Admission characteristics, resuscitation, and survival were compared between groups. Multivariate regression analyses were performed comparing survival of patients at 24 hours and at 30 days. Secondary outcomes including adverse events and causes of death were analyzed.

RESULTS

Unadjusted survival between groups receiving aPLT and FWB was similar at 24 hours (84% vs. 81%, respectively; p = 0.52) and at 30 days (60% versus 57%, respectively; p = 0.72). Multivariate regression failed to identify differences in survival between patients receiving PLT transfusions either as FWB or as aPLT at 24 hours or at 30 days.

CONCLUSIONS

Survival for massively transfused trauma patients receiving FWB appears to be similar to patients resuscitated with aPLT. Prospective trials will be necessary before consideration of FWB in the routine management of civilian trauma. However, in austere environments where standard blood products are unavailable, FWB is a feasible alternative.

Transfusion associated graft versus host disease in an immunocompetent individual following coronary artery bypass grafting

Transfusion associated graft versus host disease (TA-GVHD) is a rare but commonly fatal complication of transfusion of cellular blood products, which usually occurs in immunosuppressed individuals following transfusion and subsequent engraftment of viable T lymphocytes. Very rarely it may arise in apparently immunocompetent individuals. The clinical syndrome consists of fever, skin rash, diarrhoea, hepatic dysfunction, and bone marrow aplasia. The outcome is nearly always fatal. We present here a case report of fatal TA-GVHD in a “presumed” immunocompetent patient, post coronary artery bypass grafting surgery after transfusion of blood products. The patient died 24 days after transfusion.

There is a perceived increased risk of TA-GVHD following bypass grafting and other surgical procedures where cardiopulmonary bypass is required. TA-GVHD is probably underreported and the incidence is felt to be too low to warrant routine irradiation of cellular products for this group of patients. Clinicians, pathologists, and transfusion centers should be aware of this rare but devastating complication of blood transfusion after cardiac surgery.

The hazards of blood transfusion in historical perspective

The beginning of the modern era of blood transfusion coincided with World War II and the resultant need for massive blood replacement. Soon thereafter, the hazards of transfusion, particularly hepatitis and hemolytic transfusion reactions, became increasingly evident. The past half century has seen the near eradication of transfusion-associated hepatitis as well as the emergence of multiple new pathogens, most notably HIV. Specific donor screening assays and other interventions have minimized, but not eliminated, infectious disease transmission. Other transfusion hazards persist, including human error resulting in the inadvertent transfusion of incompatible blood, acute and delayed transfusion reactions, transfusion-related acute lung injury (TRALI), transfusion-associated graft-versus-host disease (TA-GVHD), and transfusion-induced immunomodulation. These infectious and noninfectious hazards are reviewed briefly in the context of their historical evolution.

[Irradiated Blood Usage in a Tertiary-care Hospital.]

BACKGROUND

Irradiated blood is used to prevent transfusion-associated graft-versus host disease in high risk patients. The guidelines for usage of irradiated blood components vary from one country to other according to their needs. But in Korea, little information is available on the current usage of and the guidelines for irradiated blood. Therefore, we analyzed the usage of irradiated blood components in Hanyang University Medical Center.

METHODS

Medical records were reviewed for 187 patients who had been transfused with irradiated blood products during the period from January 2004 to June 2005. And we investigated the proportion of irradiated blood products among the total number of blood products that were transfused during a one-year period.

RESULTS

Hematologic diseases and solid cancer patients comprised 63.7% and 24.6% respectively. The proportion of irradiated blood products among the total blood components were 25.7% of platelet concentrates, 61.4% of apheresis platelets, and 5.1% of packed red cells. Total transfused amount by disease categories and the average transfused units per patient of irradiated blood components were high in a group of patients with several hematologic diseases such as acute leukemia.

CONCLUSIONS

The use of irradiated blood components takes a great proportion in total blood product transfusions and the majority of blood components were transfused to a group of patients with a few hematologic diseases. The proper use of blood should be guided by the promotion and education of a modified usage protocol for irradiated blood products and by a continuous data analysis.

Red blood cell transfusion in clinical practice

Every year, about 75 million units of blood are collected worldwide. Red blood cell (RBC) transfusion is one of the few treatments that adequately restore tissue oxygenation when oxygen demand exceeds supply. Although the respiratory function of blood has been studied intensively, the trigger for RBC transfusion remains controversial, and doctors rely primarily on clinical experience. Laboratory assays that indicate failing tissue oxygenation would be ideal to guide the need for transfusion, but none has proved easy, reproducible, and sensitive to regional tissue hypoxia. The clinical importance of the RBCs storage lesion (ie, the time-dependent metabolic, biochemical, and molecular changes that stored blood cells undergo) is poorly understood. RBCs can be filtered, washed, frozen, or irradiated for specific indications. Donor screening and testing have dramatically reduced infectious risks in the developed world, but infection remains a major hazard in developing countries, where 13 million units of blood are not tested for HIV or hepatitis viruses. Pathogen inactivation techniques are in clinical trials for RBCs, but none is available for use. Despite serious immunological and non-immunological complications, RBC transfusion holds a therapeutic index that exceeds that of many common medications.

The impact of universal leukodepletion of the blood supply on hemovigilance reports of posttransfusion purpura and transfusion-associated graft-versus-host disease

BACKGROUND

The pathogenesis of posttransfusion purpura (PTP) and transfusion-associated graft-versus-host disease (TA-GVHD) involves patient exposure to donor platelets (PLTs) and T lymphocytes, respectively, which are removed during blood component leukodepletion (LD).

STUDY DESIGN AND METHODS

Reports of PTP and TA-GVHD to the UK hemovigilance scheme Serious Hazards of Transfusion (SHOT) from 1996 to 2005 were compared before and after implementation of universal LD during 1999.

RESULTS

There were 45 reports of PTP, with a mean of 10.3 per year before universal LD and 2.3 per year afterward (p < 0.001). All patients had received red cells, but before universal LD, only 1 of 31 (3%) cases had also received PLTs, compared to 8 of 14 (57%) afterward (p < 0.001). Thirty-four cases (76%) had human platelet antigen (HPA)-1a antibodies, whereas 11 had antibodies to other HPA specificities, only 1 of which occurred after LD. Two cases reported before LD also had heparin-dependent PLT antibodies. There were 13 reports of TA-GVHD, all fatal, of which only 2 cases of undiagnosed immunodeficiency met current UK criteria for irradiated components. Eight others had one or more risk factors: B-cell malignancy (6), steroids (1), fresh blood (1), and donor-recipient HLA haplotype share (4). Eleven cases were due to non-LD and 2 to LD components (p < 0.001). No cases have been reported since 2001. In an additional 405 cases, nonirradiated components were transfused in error to high-risk recipients, mainly on fludarabine, but none developed TA-GVHD.

CONCLUSIONS

These findings suggest that universal LD has further reduced the already low risk of TA-GVHD in immunocompetent recipients and has altered the profile of PTP cases.

Transfusion-associated graft-versus-host disease in immunocompetent patients: case series and review of the literature

BACKGROUND

Transfusion-associated graft-versus-host disease (TA-GVHD) is a fatal complication of transfusion of blood products that usually affects immunocompromised patients. Articles reporting this condition in immunocompetent recipients are usually from countries that still have problems in irradiation of blood products.

CASE REPORTS

This report presents fatal TA-GVHD in four immunocompetent patients referred from rural areas where blood irradiation is still not the routine procedure to our tertiary-care center between July 2004 and July 2005. A similar history and chronological order of events were observed: fresh whole-blood transfusion from relatives, fever, rash, liver dysfunction, diarrhea, and pancytopenia. Skin biopsies demonstrated Grade II to III GVHD involvement. Marrow biopsies showed hypoplasia. In two cases, HLA typing studies were performed. Donors were homozygous for a shared HLA haplotype in the patients. All cases were admitted to the intensive care unit within 3 weeks after transfusions with the diagnosis of sepsis, which rapidly progressed to septic shock and multiorgan failure. Another common observation was Candida albicans growth in blood cultures. Unfortunately, all died despite prompt and appropriate sepsis treatment, along with immunomodulatory therapy.

CONCLUSION

TA-GVHD is probably more prevalent than reported in the literature. It must be considered in the differential diagnosis, if the patient with a recent transfusion history admits with fever, skin rash, abnormal liver function tests, and pancytopenia associated with hypoplastic marrow. In rural areas where gamma irradiation is not possible, the overall policy of transfusion (e.g., restriction of transfusion indications and alternative methods for pathogen inactivation) should be reassessed.

Noninfectious complications of blood transfusion

CONTEXT

Serious noninfectious complications are far more likely to occur than viral disease transmission from blood component transfusion.

OBJECTIVE

To compile a comprehensive list of the noninfectious risks of transfusion, examples of published risk estimates, and summaries of recent information regarding cause, prevention, or management of noninfectious transfusion risks.

DATA SOURCES

Information was obtained from peer-reviewed English-language medical journal publications since 1990.

CONCLUSIONS

Early complications, although potentially more serious, usually occur less frequently (<1 in 1000 transfusions) than late complications, which often affect more than 1% of recipients. Areas of active investigation and discussion include acute hemolytic reactions, transfusion-related acute lung injury, red cell alloimmunization, platelet transfusion refractoriness, and transfusion immunosuppression. Continued effort toward research and education to promote recognition and prevention of noninfectious complications associated with blood components is warranted.

Fatal transfusion-associated graft-versus-host disease in an immunocompetent recipient of a volunteer unit of red cells

BACKGROUND

Transfusion-associated graft-versus-host disease (TAGVHD) is a lethal complication of transfusion of nonirradiated cellular blood components to a susceptible recipient.

CASE REPORT

An 82-year-old man underwent cardiac surgery during which he received 6 units of red cells (RBCs) and a 6-unit pool of platelets (PLTs). He was discharged with a normal white blood cell (WBC) count and hemoglobin (Hb) level and a PLT count of 104x10(9) per L. He was readmitted 2 weeks later with a diffuse erythematous rash, a sore throat, and difficulty swallowing. His WBC count was 2.1x10(9) per L, his Hb level was 12.0 g per dL, and his PLT count was 131x10(9) per L. The next day he had worsening cytopenias: WBC count, 1x10(9) per L; Hb level, 10.9 g per dL; PLT count, 104x10(9) per L. He also had diarrhea. A marrow biopsy showed a severe hypoplasia without evidence of malignancy. A skin biopsy showed Grade II GVHD. The patient worsened and despite aggressive therapy he expired on Postoperative Day 42. DNA-based HLA testing of the 12 blood donors was performed. One of the RBC donors was found to be homozygous for an HLA Class I and Class II haplotype in the patient.

CONCLUSION

This is the first reported case in the United States of fatal TAGVHD from RBCs in an immunocompetent patient who received a randomly selected unit of RBCs from a donor who was homozygous for a shared HLA haplotype. The policy of selective irradiation should be reexamined.

Transfusion-associated graft-versus-host disease

Transfusion-associated graft-versus-host disease (TA-GVHD) is a relatively rare and interesting entity. Despite a range of pathophysiological and therapeutic approaches, it has a high mortality. It is possible to prevent the disease by prophylaxis only. It is possible to miss the entity in routine clinical practice and reach a different diagnosis due to its non-specific signs and symptoms. Four patients with signs and symptoms suggestive of TA-GVHD were evaluated and the literature reviewed. The transfusion history was of great importance, as was the exclusion of other conditions that may present with similar signs and symptoms (fever, skin rash, diarrhea, pancytopenia, icterus and renal failure). Confirmation of TA-GVHD was by skin biopsy. TA-GVHD must be considered as a differential diagnosis in patients who present with fever, pancytopenia, diarrhea, skin rash and icterus, and the transfusion history must be questioned. Mortality is very high despite various therapeutic approaches. This makes prophylaxis essential. TA-GVHD can be prevented by irradiation of blood products and by avoiding the use of blood transfusions from family donors.

Fatal graft-versus-host disease after living donor liver transplantation: differential impact of donor-dominant one-way HLA matching

Graft-versus-host disease (GVHD) is an uncommon but potentially devastating complication following liver transplantation. Recently, it was shown that use of a human leukocyte antigen (HLA)-homozygous donor leading to one-way HLA matching significantly increases the risk of GVHD after living donor liver transplantation (LDLT). However, the precise impact of HLA matching between donor and recipient on the risk of GVHD is not yet clear. We surveyed instances of fatal GVHD following LDLT in Japan and reviewed all 8 cases in detail, especially with respect to HLA matching. Serological typing showed that 7 of those cases had donor-dominant one-way HLA matching in the 3 loci of HLA-A, -B, and -DR, while one had donor-dominant one-way HLA matching in the 2 loci of HLA-A and -DR and identical alleles in the B locus. However, DNA typing revealed that the latter case had 1-way HLA matching in the 3 loci. Further, we analyzed HLA typing of 906 donor-recipient pairs who underwent LDLT. There were 5 cases with donor-dominant one-way matching in 2 loci and 2 with donor-dominant one-way matching in 1 locus. All of those cases except 1, who died from an unrelated cause, are alive without an obvious presentation of GVHD. In conclusion, our results suggest that the total number of loci with donor-dominant one-way HLA matching is important for determining the risk of fatal GVHD following LDLT, and that DNA typing of HLA alleles is indispensable in some cases to identify the true risk of donor-dominant 1-way HLA matching.

Diagnosis of transfusion-associated graft-vs.-host disease: the importance of short tandem repeat analysis

Transfusion-associated graft-vs.-host disease (TA-GvHD) can occur following transfusion of blood products containing immunocompetent lymphocytes, usually from HLA homozygous donors, into immunocompromised patients sharing one HLA haplotype with the donor. The diagnosis of TA-GvHD may be delayed due to the initial nonspecific clinical features involved. Investigations to detect the presence of donor-derived cells in the blood and/or affected tissues of the recipient are essential to confirm the diagnosis. We report the investigation of suspected TA-GvHD using short tandem repeat (STR) analysis, to detect the presence of donor cells (chimerism), in an immunocompetent patient admitted for coronary artery bypass surgery. Peripheral blood and skin biopsies (from affected and nonaffected sites) from the patient and peripheral blood samples from the implicated donors were taken for HLA typing and STR analysis. STR analysis revealed the presence of donor material in the patient's peripheral blood sample and in DNA extracted from the affected skin biopsy but not the unaffected biopsy, suggesting lymphocytes from this donor were responsible for the development of TA-GvHD. Furthermore, HLA typing results supported the diagnosis of TA-GvHD. These data demonstrate the use of STR and HLA analysis as effective tools in the diagnosis of TA-GvHD.

Novel processes for inactivation of leukocytes to prevent transfusion-associated graft-versus-host disease

Transfusion-associated graft-versus-host disease (TA-GVHD) is a serious complication of blood component transfusion therapy. Currently, cellular blood components for patients recognized at risk for TA-GVHD are irradiated prior to transfusion in order to prevent this complication. Considerable progress has been made in elucidating the pathophysiology of this highly morbid complication, but questions as to which patients are at risk and what is the most robust technology to prevent TA-GVHD remain. As new technologies for inactivating or modulating leukocyte function are introduced, the question of how to evaluate these technologies becomes relevant. Over the past two decades, a number of research groups have explored technology to inactivate infectious pathogens and leukocytes contaminating cellular blood components. Few clinicians have an in-depth understanding of the methods or the criteria for selection of how to approach new technologies for leukocyte inactivation with potential to replace current methods. This mini review focuses on the salient aspects of current and evolving technology for prevention of TA-GVHD.

Network computer-assisted transfusion-management system for accurate blood component-recipient identification at the bedside

BACKGROUND

ABO-mismatched transfusions caused by human error are among the most serious problems in transfusion therapy. The major cause is misidentification of a recipient or a blood component at the bedside.

STUDY DESIGN AND METHODS

A network computer-assisted transfusion-management system has been developed with bar coding as a fail-safe/fool-proof system for accurate component-recipient identification at the bedside, which allows us to monitor the usage of blood components in real time. The efficacy of this system was evaluated to prevent human errors by monitoring the transfusion process via the network and analyzing voluntary and mandatory reports with regard to transfusion errors over a 3-year period. The crossmatch-to-transfusion ratio for operations and outdate rate of RBCs were calculated to assess economic benefit.

RESULTS

More than 60,000 blood components have been transfused perfectly to the intended recipients via the network, and one human error was prevented by the system. After establishment of the network system, the crossmatch-to-transfusion ratio for operations and outdate rate of RBCs have been gradually reduced from around 2.5 to 1.8 and from 3.9 to 0.32 percent, respectively.

CONCLUSION

The network computer-assisted management system greatly contributes to safe and efficient transfusion therapy.

Transfusion-associated GVHD: 10 years’ experience at the American University of Beirut-Medical Center

BACKGROUND

Although rare, transfusion-associated GVHD (TA-GVHD) is a fatal complication of blood transfusion in which active lymphocytes from the donor attack and destroy recipient organs and tissues.

STUDY DESIGN AND METHODS

A search of patient records was carried out at the American University of Beirut-Medical Center, looking for patients who developed TA-GVHD over a 10-year period extending from 1991 to 2001. Relevant information was collected and analyzed.

RESULTS

A total of 10 records were found as a result of this search. All were immunocompetent and received fresh nonleukoreduced, nonirradiated blood. The majority received the transfusion at outside periphery hospitals. They received different treatment modalities. The mortality rate was 100 percent.

CONCLUSION

TA-GVHD is a serious complication with very high mortality. Effective prevention guidelines should be established in Lebanon including irradiation and the creation of a central blood bank.

Transfusion-associated graft vs. host disease after donor-specific leukocyte transfusion before kidney transplantation

Transfusion-associated graft vs. host disease (TA-GVHD) is a well-known but rare complication that follows infusion of histo-incompatible lymphoid cells, often seen in individuals with impaired cellular immunity. However, we present here a case report of fatal TA-GVHD in a 'presumed' immunocompetent patient after transfusion of a freshly isolated buffycoat from a relative as part of our protocol to prepare the patient for living-related kidney transplantation. To confirm the diagnosis of TA-GVHD, a polymerase chain reaction was used to detect donor cells in various affected tissues. Furthermore, the immune reactivity of the patient against donor and vice versa was tested on samples taken before transfusion using limiting dilution assays. Our patient received a transfusion with blood from a donor who was homozygous at the human leukocyte antigen (HLA) class I loci. Despite incompatibility for HLA class II, infused donor T lymphocytes were not rejected and became engrafted. The patient did not have cytotoxic T lymphocytes to reject the donor cells. DNA polymorphism studies on several organ biopsies confirmed the presence of infiltrating cells of donor origin. This report illustrates the possibility, in the general patient population, of developing TA-GVHD from whole blood transfusion. In the case of pre-transplant blood transfusion, the patient and donor have to be HLA-typed and special care should be taken in the situation of donor homozygosity for HLA class I, even in the presence of HLA class II incompatibility. Protocols in which donor-specific blood or bone marrow transfusions are given in an attempt to modulate the immune system should exclude these combinations.

HLA ALLOIMMUNIZATION OF SURGICAL PATIENTS BY TRANSFUSION WITH BEDSIDE LEUKOREDUCED BLOOD COMPONENTS

High efficiency leukocyte reducing filters can remove more than 99.9-99.99% of white cells from cellular blood components and are considered to be effective in decreasing HLA alloimmunization of patients with haematological malignancies. A multi-institution study was performed to determine whether white cell filtration would also be effective in preventing alloimmunization in surgical transfusion recipients. Patients who were to receive red cell blood transfusions during and/or within 48 hours after surgery were randomly assigned to receive red cells/ fresh frozen plasma that had been leukoreduced using a high efficiency filter at the bedside or buffycoat-depleted red cells transfused through an aggregate filter. Of 87 patients with no alloantibodies at entry, 17% (8/47) of those in the leukoreduction group, who received a mean of 0.3 x 10(6) leukocytes as a result of their transfusions, produced lymphocytotoxic antibodies at day 14 after transfusion, compared to 5% (2/40) in the buffycoat-depleted group, who had received a mean of 1,234.2 x 10(6) leukocytes. This difference in the alloimmunization rate between the two arms was not statistically significant. Reduction of leukocytes by bedside filtration does not appear to be effective in preventing HLA alloimmunization in surgical transfusion recipients. The alloimmunized cases suggest that an indirect allorecognition pathway may be involved in the formation of anti-HLA. Further measures are needed to reduce alloimmunization of immunocompetent patients.

Practical management of anticoagulation, bleeding and blood product support for cardiac surgery part two: Transfusion issues

We summarise recent advances in transfusion medicine applicable to cardiac surgery and cardiac transplantation. It is important that clinicians know the risks of blood transfusion in Australia. They should also be aware of the different types of transfusion reaction so that there is early recognition and investigation. Blood conservation strategies including acceptance of normovolaemic anaemia in clinically stable patients are important in reducing the requirement for red cell transfusion. Cytomegalovirus (CMV) seronegative blood products are recommended for heart transplant recipients with no evidence of prior CMV infection. Leucodepletion of units of unknown CMV status reduces the risk of CMV infection and are an acceptable alternative when seronegative units are unavailable. Leucodepletion of cellular blood products has been shown to reduce infection rates postoperatively in a large trial involving cardiac surgical patients. Further studies are needed to confirm this promising finding. Irradiation of blood products eliminates the risk of transfusion-associated graft versus host disease. Routine preoperative screening for cold agglutinins is no longer recommended.

Prevention of transfusion-associated graft-versus-host disease by inactivation of T cells in platelet components

Patients with hematological malignancies and infants with congenital immunodeficiencies who received blood are two of many populations at risk for transfusion-associated graft-versus-host disease (TA-GVHD). Of the methodologies (eg, photoinactivation, peglyation, ultraviolet light, and irradiation) that can be used to prevent TA-GVHD, only irradiation of whole blood and cellular components is currently accepted practice of the US Food and Drug Administration (FDA). Among the newer methods that have been developed to reduce the risks of bacterial and viral contaminants of platelet transfusions, photochemical treatment (PCT) using psoralens and long-wavelength ultraviolet (UVA) irradiation modifies bacterial and viral genomes sufficiently to inhibit replication. Among a broad group of compounds, the synthetic psoralen compound amotosalen hydrochloride (HCl) (S-59) has been shown to be particularly effective in inactivating bacteria and viruses, without adversely affecting in vitro and in vivo platelet function.

Survival of transfused donor white blood cells in HIV-infected recipients

The appearance and expansion of donor white blood cells in a recipient after transfusion has many potential biologic ramifications. Although patients with HIV infection are ostensibly at high risk for microchimerism, transfusion-associated graft-versus-host disease (TA-GVHD) is rare. The purpose of this study was to search for sustained microchimerism in such patients. Blood samples were collected from 93 HIV-infected women (a subset from the Viral Activation Transfusion Study, an NHLBI multicenter randomized trial comparing leukoreduced versus unmodified red blood cell [RBC] transfusions) before and after transfusions from male donors. Donor lymphocytes were detected in posttransfusion specimens using a quantitative Y-chromosome-specific polymerase chain reaction (PCR) assay, and donor-specific human leukocyte antigen (HLA) alleles were identified with allele-specific PCR primers and probes. Five of 47 subjects randomized to receive nonleukoreduced RBCs had detectable male lymphocytes 1 to 2 weeks after transfusion, but no subject had detectable male cells more than 4 weeks after a transfusion. In 4 subjects studied, donor-specific HLA haplotypes were detected in posttransfusion specimens, consistent with one or more donors' cells. None of 46 subjects randomized to receive leukoreduced RBCs had detectable male lymphocytes in the month after transfusion. Development of sustained microchimerism after transfusion in HIV-infected patients is rare; HIV-infected patients do not appear to be at risk for TA-GVHD.

Non-infectious complications of transfusion therapy

Blood transfusion is considered safe when the infused blood is tested using state of the art viral assays developed over the past several decades. Only rarely are known viruses like HIV and hepatitis C transmitted by transfusion when blood donors are screened using these sensitive laboratory tests. However, there are a variety of transfusion risks which still remain that cannot be entirely eliminated, many of which are non-infectious in nature. Predominantly immune-mediated complications include the rapid intravascular or slow extravascular destruction (hemolysis) of transfused red cells or extravascular removal of platelets by pre-formed antibodies carried by the transfusion recipient. Alternatively, red cells can be damaged when exposed to excessive heat or incompatible intravenous fluids before or during the transfusion. Common complications of blood transfusion that at least partly involve the immune system include febrile non-hemolytic and allergic reactions. While these are usually not life-threatening, they can hamper efforts to transfuse a patient. Other complications include circulatory overload, hypothermia and metabolic disturbances. Profound hypotensive episodes have been described in patients on angiotensin-converting enzyme (ACE) inhibitors who receive platelet transfusions through bedside leukoreduction filters. These curious reactions appear to involve dysmetabolism of the vasoactive substance bradykinin. Products contaminated by bacteria during blood collection and transfused can cause life-threatening septic reactions. A long-term complication of blood transfusion therapy unique to chronically transfused patients is iron overload. Less common - but serious - reactions more specific to blood transfusion include transfusion-associated graft-versus-host disease and transfusion-associated acute lung injury. Many of these complications of transfusion therapy can be prevented by adhering to well-established practice guidelines. In addition, individuals who administer blood transfusions should recognize these complications in order to be able to quickly provide appropriate treatment.

Inactivation of infectious pathogens in labile blood components: meeting the challenge

Substantial improvement in the safety of blood transfusion has been achieved through the addition of new tests, such as nucleic acid tests, yet residual risk associated with transfusion of blood components persists. Transfusion of blood components has been implicated in the transmission of viruses, bacteria, and protozoa. While it is commonly recognized that hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV), and the retroviruses, such as human immunodeficiency virus (HIV) and the human lymphotrophic viruses (HTLV) can be transmitted through cellular components, other pathogens are emerging as potentially significant transfusion-associated infectious agents. For example, transmission of protozoan infections due to trypanosomes and babesia have been reported. In addition to viral and protozoal infectious agents, bacterial contamination of platelet and red cell concentrates continues to be reported; and may be an under-reported transfusion complication. More importantly, new infectious agents may periodically enter the donor population before they can be definitively identified and tested for to maintain consistent safety of the blood supply. The paradigm for this possibility is the HIV pandemic, which erupted in 1979. During the past decade a number of methods to inactivate infectious pathogens in labile blood components have been developed and have entered the advanced clinical trial phase.

New technologies for the inactivation of infectious pathogens in cellular blood components and the development of platelet substitutes

Despite the increased safety of blood components, achieved through improved donor selection and testing, transfusion recipients remain at risk of transfusion-associated diseases. Transfusion of cellular blood components has been implicated in transmission of viral, bacterial and protozoan diseases. While it is commonly recognized that hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV), and retroviruses, such as human immunodeficiency virus (HIV) and the human lymphotrophic viruses (HTLV), can be transmitted through cellular components, other pathogens are emerging as potentially significant transfusion-associated infectious agents. For example, transmission of protozoan infections due to trypanosomes and Babesia have been reported. In addition to viral and protozoan infectious agents, cases of bacterial contamination of platelet and red cell concentrates continue to be reported and may be an under-reported transfusion complication. More importantly, new infectious agents continue to enter the donor population, and there is an inherent time delay before the new pathogens are definitively identified and new tests implemented in order to maintain consistent safety of the blood supply. The paradigm for this problem is the HIV pandemic. During the past decade a number of methods for inactivating infectious pathogens in platelet concentrates have been investigated as a strategy to improve the safety of platelet transfusion therapy. One method of treating platelet concentrates to inactive pathogens has now reached the advanced clinical trial phase in the United States and Europe. Similar efforts with a new class of compounds are underway for red cell concentrates, and two of these are in early phase trials. In addition to studies with allogeneic platelets and red cells, a number of laboratories have described methods for developing platelet substitutes or modified platelets to avoid the use of traditional platelet concentrates as a means to improve safety.

Irreversible loss of donor blood leucocyte activation may explain a paucity of transfusion-associated graft-versus-host disease from stored blood

Transfusion-associated graft-versus-host disease (TA-GVHD) is usually a fatal outcome of blood transfusion therapy, caused by viable leucocytes contained in the donor blood. Most cases of TA-GVHD occur when less than 4-d-old blood is transfused. We therefore examined the molecular changes that occur during storage that may account for the paucity of TA-GVHD following infusion of older blood. Leucocyte number and viability were essentially unchanged from freshly obtained blood, but the expression of cell-surface lymphocyte activation antigens (CD3, CD4, CD28, CD2, CD45) decreased rapidly within the first 24 h and continued to fall to less than 20% of original levels by d 9 of storage at 4 degrees C. The decrease in CD antigen expression directly correlated with a decreasing ability to induce activation of the T-lymphocyte cellular signal transduction pathway. As a result, cells became less responsive in a mixed lymphocyte culture (MLC) by d 3, with abrogation of the MLC responsiveness by d 5. Donor leucocytes stored for 4 d or less at 4 degrees C were able to partially re-express CD antigens and reconstitute their signalling pathway when placed at 37 degrees C. whereas those stored for more than 4 d were not. These irreversible changes result from a permanent downregulation of donor cell protein synthesis. These findings provide a mechanism to explain the paucity of TA-GVHD following transfusion of blood that is more than 4 d-old. Further study may show that aged blood provides additional assurances for the prevention of TA-GVHD; however, use of aged blood should not replace current protocols using irradiation.