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Background: Policies and practices with regard to transfusion-related acute lung injury (TRALI) diagnosis, laboratory investigation of TRALI cases, and donor deferral and donor management are not standardized., Study Design and Methods: A Web-based survey was designed and administered to participating AABB member institutions in July 2006., Results: The survey response rate was highest for donor centers, followed by larger hospital blood banks and transfusion services. Laboratory case workups regularly included HLA Class I and II antibody testing of donors followed less frequently by HNA antibody testing; recipient specimens for leukocyte antigen typing were usually not obtained, even if indicated as part of the planned workup. Several different criteria (i.e., all donors, female donors only, case by case determination) were used to select which donors should be tested. There was agreement that donors should be deferred if implicated in a TRALI case (i.e., antibody-cognate antigen match); however, donor management policies varied in other scenarios. The final diagnosis of TRALI was often (45%-66% depending on institutional type) based on a combination of clinical and serologic findings rather than on adherence to the clinical definition recommended by the Canadian Consensus Conference. Many TRALI policies appeared to be decided on a case-by-case basis at the discretion of the institution's medical director., Conclusions: There is wide variability in procedures and policies related to the diagnosis of and donor investigation and/or management of TRALI cases. Lack of a consensus approach may partly reflect limitations in understanding of TRALI pathogenesis. The survey suggests that increased education of transfusion medicine practitioners is needed.

Background: TRALI is usually an immunologic reaction to WBC antibodies in infused plasma and ranks second only to ABO mismatch as a cause of transfusion-associated death. Implicated donors are usually multiparous women (>/=3 pregnancies)., Study Design and Methods: Two fatal cases of TRALI were evaluated by reviewing clinical and laboratory findings and characterizing alloantibodies present in donor plasma. Investigation for WBC antibodies was by lymphocytotoxicity (LCT), FlowPRA (FlowPRA, One Lambda, Inc.) and granulocyte immunofluorescence and agglutination assays. Patient 1 was a 62-year-old man with chronic T-cell lymphocytic leukemia, and Patient 2 was a 54-year-old woman undergoing a cadaveric kidney transplant. Both patients developed acute respiratory distress and hypotension during (Patient 1) and approximately 30 minutes after (Patient 2) transfusion. Fulminant pulmonary edema ensued in both cases necessitating mechanical ventilation and both patients died within 24 hours of the onset of respiratory complications., Results: The donors of the implicated blood components were women with a history of two pregnancies but no blood transfusions. Weak apparently panreactive granulocyte antibodies were detected with flow cytometry. However, in the granulocyte agglutination test, strong antibodies specific for human neutrophil antigen (HNA)-3a (5b) were identified in both donors., Conclusion: It is concluded that female blood donors with only two previous pregnancies can form clinically important granulocyte-reactive alloantibodies leading to fatal TRALI reactions in recipients. The sometimes devastating consequences of TRALI should prompt the development of strategies to prevent or reduce its incidence. Further research is warranted to investigate recipient and donor factors responsible for TRALI, including whether 5b (HNA-3a) alloantibodies are especially prone to cause severe reactions, and to better characterize the HNA-3a (5b) antigen, particularly at the molecular level.

Background: Patients with sickle cell anemia may develop serious, life-threatening hemolytic transfusion reactions (HTRs). More severe anemia may develop after the HTR than was present before transfusion, which suggests the possibility of an increased rate of hemolysis of autologous red cells., Study Design and Methods: The signs and symptoms occurring during eight severe HTRs that occurred in five patients with sickle cell anemia were reviewed, as were published reports by other investigators. Calculations of red cell production and destruction incorporating known correction factors for reticulocyte maturation were performed to determine the most probable mechanism for the striking drop in hematocrit observed in several instances., Results: A characteristic constellation of findings was recognized in some severe HTRs in patients with sickle cell anemia. Calculations of daily red cell production and senescence indicated that a marked drop in hematocrit occurs when erythropoiesis is suppressed in a patient with a short red cell life span and that this could account for severe posttransfusion anemia when donor red cells are hemolyzed during an HTR., Conclusion: A sickle cell HTR syndrome was defined. A rapid increase in the severity of anemia occurs in patients with sickle cell anemia when all donor red cells are hemolyzed during an HTR and when there is suppression of erythropoiesis, as commonly occurs as a result of transfusion or concomitant illness. Although an increased rate of hemolysis of autologous red cells may also occur, more definitive data are required to document that in these patients.

There is currently less than a one in a million chance that a blood transfusion within the United States will be complicated by a parasitic infection. However, changes in population demographics and increases in international travel and immigration may all contribute to an increase in the number of parasitemic individuals who present as prospective blood donors. Consequently, a need may arise to develop new policies to prevent transfusion-transmitted parasitic infections. In the present review, the following parasitic infections of concern to the safety of the US blood supply will be discussed: malaria, Chagas' disease, babesiosis, leishmaniasis, toxoplasmosis, and microfilariasis.

The American public has become aware that viral infections can be transmitted by blood transfusions; however, less attention has been paid to nonviral agents that are similarly transmitted. Although donors are tested routinely for serologic evidence of Treponema pallidum infection (syphilis), there are no other bacterial infections for which donors are routinely tested, and no testing is done routinely to detect parasitic infections. Although current preventive strategies appear effective in preventing the transmission of nonviral agents by transfusion, changing population demographics, increased travel and immigration, and increased occurrence of certain asymptomatic bacterial infections in blood donors may require new policies to maintain the safety of the U.S. blood supply. This review focuses on the parasitic and bacterial infections that might pose a risk to transfusion recipients in the U.S.

Three years' experience with the routine use of an abbreviated crossmatch procedure is reported. If a patient had no known history of and/or no currently demonstrable unexpected antibodies, ABO and Rh type specific blood was crossmatched at the time of need by using an immediate spin saline abbreviated crossmatch. Once blood was issued, both a 37 degrees C incubation and an antiglobulin crossmatch were done using the same tube employed for the abbreviated crossmatch. This served as a check that clinically significant antibodies were not overlooked. None of the 19,818 patients transfused following an abbreviated crossmatch suffered an acute hemolytic transfusion reaction as a result of this strategy; however, two patients may have manifested asymptomatic hemolysis. This approach to compatibility testing might be appealing to hospitals faced with fiscal limitations and new regulations affecting hospital reimbursement.

The transfusion of whole blood and blood components is usually a temporarily effective means of correcting red cell, white cell, platelet, and coagulation factor deficits. Unfortunately, blood and blood components are occasionally unavoidably unsafe, which results in a spectrum of adverse reactions following transfusion. These reactions may be immunologically or nonimmunologically mediated, and may vary in severity from mild to fatal. Physicians should weigh the potential risks versus the potential benefits of each blood transfusion. Only when the benefits clearly outweigh the risks should a blood transfusion be administered. Transfusionists must carefully monitor each blood transfusion for signs and symptoms of transfusion reactions in order to minimize their adverse effects.