Febrile Nonhemolytic Transfusion Reactions Research Articles

Hyperconcentrated (Dry) Versus Standard Platelet Apheresis: An In Vitro Quality Study.

Introduction: Platelet concentrates (PC) collected by apheresis are effective in supporting deeply thrombocytopenic patients. The reduced risk of multiple allogeneic exposure and transmissible infectious diseases together with the high WBC depletion and diminished transfusion reactions are the main advantages offered by PC transfusion. At moment, the availability of several synthetic solutions for platelets storage permits to prepare hyperconcentrate(dry) apheresis platelets with the advantage of reducing febrile non-hemolytic transfusion reactions and, in low body weight patients the citrate toxicity, without the necessity of further manipulations. The aim of this study was to test the quality of 20 dry platelets (DP) in comparison to 20 standard plateletpheresis (SP) concentrates.Materials and methods: A total of 40 apheresis procedures were performed by the single-needle Cobe Trima separation device (Gambro BCT, Lakewood, CO, USA) collecting either DP or SP concentrates. Within 1h after collection, the bag containing DP was added with the appropriate amount (70% of DP final volume) of synthetic solution for platelets storage (SSP, MacoPharma). Both DP and SP concentrates were stored at room temperature with gentle agitation for 4 days. For both concentrates, platelet yield was calculated and in vitro studies of membrane glycoproteins expression and aggregation at day +1 and day +4 were carried out.Results: The comparison between 20 DP and 20 SP concentrates in terms of ability to aggregate in vitro and membrane glycoproteins expression at day +1 and day +4 of storage is reported in table A and B respectively.Conclusions: The in vitro tests documented a major activation of dry platelets. In particular, the ability to aggregate was reduced in the 20 DP concentrates analised and this phenomenon was more evident at day +4 of storage. The alteration of membrane glycoproteins expression (markers of storage lesion) confirms the lower in vitro quality of DP concentrates. The effectiveness of this new blood component in vivo should be evaluated in a controlled clinical trial.Table AAt collectionDay +1Day +4SPDPSPDPSPDPCollagen μg/ml 4938897828053ADP 10 μM32112416165Ristocetin 1.5 mg/ml919777817152Collagen 10 μg/ml + Adrenaline 10 μM989593949380ADP 10 μM + Adrenaline 10 μM877276615730Table BAt collectionDay +1Day +4SPDPSPDPSPDPGPIb alfa (MFI)5.065.756.316.135.264.54GPIIb-IIIa (MFI)35.4736.7134.6137.731.7640.9GP IV (MFI)11.4911.411.6710.2811.6511.38GP 5324.2327.1121.7425.9121.4631.84GMP 14021.7929.2922.6530.3820.5834.89

Febrile nonhaemolytic transfusion reaction caused by antibodies against human platelet antigen 5a

Anti-human platelet antigens (HPA) alloantibodies are seldom involved in febrile nonhaemolytic reactions (FNHTRs). We describe a case in which anti-HPA-5a alloantibodies are related to an FNHTR. We studied the specificity of the alloantibodies by flow cytometry, ELISA and MACE. Typing of donors and the patient was performed by sequence-specific polymerase chain reaction. The alloantibodies were found reactive with HPA-5a antigens. The patient was HPA-5b/b, whereas the donor of the platelet apheresis involved in the FNHTR was HPA-5a/a. Despite the low frequency of anti-HPA-5a antibodies, they might be responsible for FNHTR.

Pre‐storage leucocyte depletion and transfusion reaction rates in cancer patients

Passenger leucocytes transfused with allogenic blood are responsible for potential adverse effects. The impact of pre-storage leucodepletion (in-line filtration) of all whole blood units on transfusion reaction rate among patients suffering from cancer was retrospectively studied, comparing all reactions following red blood cell (RBC) transfusions during 2 years of pre-storage vs. 2 years of selective (bedside) leucodepletion. During selective leucodepletion, 5165 RBC units - of which 2745 were bedside filtered units- were transfused to 866 patients. Twenty-eight reactions were recorded: 22 (15 in the bedside group) febrile non-haemolytic transfusion reactions (FNHTR) and six allergic reactions (five in the bedside group). The overall percentage of reactions was 0.54 (0.76 for bedside) and 0.42 for FNHTR (0.54 for bedside). During pre-storage leucodepletion, 4116 RBC units were transfused to 841 patients. Eleven reactions were recorded: four FNHTR and seven allergic reactions (urticaria). The percentage of reactions for transfused RBC units was 0.26 (0.09 for FNHTR). Comparison between pre-storage filtration and bedside filtration with regard to FNHTR showed an odds ratio of 2.80 (95% confidence interval = 0.83-14.87) for bedside filtration. The study suggests that, for transfused patients affected by cancer, pre-storage leucodepletion is more effective than selective (bedside) filtration in reducing the incidence of transfusion reactions (FNHTR).

Haemovigilance in a general university hospital: need for a more comprehensive classification and a codification of transfusion‐related events

The purpose of this study was to analyse the transfusion-related events recorded in a general university hospital. The method we used was retrospective analysis of the data collected between 1999 and 2003. The incidence of transfusion reactions (n = 394) was 4.19 per 1000 blood products distributed: 59% (n = 231) were febrile non-haemolytic transfusion reactions; 22% (n = 88) were caused by allergy; 5% (n = 21) were caused by bacterial infection; and 14% (n = 54) were classified as other reactions. Platelet concentrates gave rise to a significantly greater number of reactions than erythrocyte concentrates and fresh-frozen plasma. Transfusion errors and near-miss events were also observed and were analysed separately. A series of transfusion-related events, such as haemosiderosis, metabolic disturbances or volume overload, were not reported. Our experience prompts us to propose a more comprehensive classification and codification of transfusion-related events.

Febrile nonhemolytic transfusion reactions. Management by premedication and cost implications in adult patients.

Febrile nonhemolytic transfusion reactions (FNHTRs) cause unwelcome interruptions during the course of blood product transfusions and necessitate measures to verify the nature of the reaction and to exclude certain dangerous reactions, such as hemolytic and septic phenomena. To examine transfusion medicine data to determine the clinical implications of the routine administration of antipyretic medication to adult patients before transfusion for the prevention of FNHTRs. A retrospective review was conducted of FNHTR data during 5 years (1998-2002), and a determination was made of the cost of a transfusion complicated by an FNHTR. In addition, a comparative cost analysis was performed using our data and published data on the incidence of FNHTRs. The clinical implications of medication with respect to possible drug-induced adverse effects were assessed, as well as the potential interference with diagnosing other forms of transfusion reactions and the mitigation of the clinical effect of an FNHTR. For nearly 120,000 U of transfused blood components, approximately 80% of which were preceded by antipyretic medication during the study period, the overall incidence of FNHTR was found to be 0.09%. Furthermore, there was no evidence of antipyretic-associated complications, nor any evidence that antipyretics prevented the recognition of other more dangerous complications of transfusions. Our findings indicate that this practice provides significant advantages to the recipient of a transfusion, but does not appear to yield significant cost benefits for the health care provider.

Platelet activity in washed platelet concentrates.

Life-threatening anaphylaxis or febrile nonhemolytic transfusion reactions after transfusion of platelet concentrates (PCs) is a serious clinical problem caused by the sensitizing of recipients to plasma components, such as immunoglobulin A, or by cytokines. There is a possible indication for washing of PCs in these thrombocytopenic patients. However, only platelets that show activation after physiological stimulation are useful. We determined the spontaneous and induced activation of platelets before and after washing. We investigated 11 consecutive single-donor-apheresis PCs. After production and leukocyte-depletion the PCs were washed in 15%, acid-citrate-dextrose-solution. The spontaneous and the adenosine diphosphate (ADP)-induced, as well as collagen-induced activation, were determined by flow cytometry. Additionally, ADP- and collagen-induced aggregation were measured. Unwashed platelets (16.1%) were activated spontaneously. The washing of PCs led to a threefold increase of spontaneous activation of platelets (47.4%). Because of increased spontaneous activation after washing we could demonstrate cytometrically a loss of induced activation of washed platelets. Furthermore, washing resulted in an impaired ADP-induced aggregability of platelets. These results have led us to reduce the frequency of washing of PCs in our institution, where the only current indication for washing of PCs is in patients with a history of severe nonhemolytic transfusion reactions.

Leukoreduction filtration of blood with sickle cell trait

Leukoreduction of cellular blood products by filtration has been shown to decrease the incidence of febrile nonhemolytic transfusion reactions, transmission of leukocyte-associated viruses, and HLA alloimmunization. However, the increasing popularity of leukofiltering blood products over the past few years has highlighted specific filtration failures associated with sickle trait (hemoglobin AS) blood. Sickle trait blood does not filter adequately, which leads to prolonged or incomplete filtration, often with a higher number of postfiltration leukocytes in the unit than the mandated minimal residual volume of <1 to 5 × 10 6. This review of the literature highlights various parameters that affect the adequacy of filtration of blood products, including effects of temperature, pH, osmolarity, type of anticoagulant, time of storage, and oxygen saturation of the blood unit. A combination of these factors likely contributes to the frequent filtration failure of sickle trait products. Although blood units are not routinely screened for sickle cell hemoglobin, administration of units with sickle trait red blood cells can be disadvantageous to certain patient populations. This review concludes with a discussion of different approaches to screening blood units for sickle cell trait.

Interleukin 1 beta and tumor necrosis factor levels in stored platelet concentrates and the association with gene polymorphisms.

Cytokines (IL-1beta and TNF) generated by WBCs during storage of PLT concentrates have been associated with febrile nonhemolytic transfusion reactions. This study was undertaken to investigate whether there is an association between the polymorphisms of IL1B -511C/T and +3953C/T, IL1RN intron 2 VNTR and TNFA-308G/A genes and the increase of cytokines during the storage of PLT concentrates produced by plasma-rich PLTS (PRP-PC) or apheresis PLTs. Thirty PRP-PCs were studied and a progressive increase of IL-1beta and TNF during storage was revealed. IL1-beta and TNF levels were inversely correlated with the content of PLTs in PRP-PCs detected on Day 3 (p = 0.004) and Day 5 (p = 0.019), but not on Day 7. There was association of IL1B-511T polymorphism and IL-1beta levels (Day 5, p = 0.063, only tendency and on Day 7, p = 0.038, significant). There was no association of the other polymorphisms (IL1B+3953C/T, IL1RN intron 2 and TNFA-308G/A) with their respective cytokines. The great variation of cytokine levels in the plasma of PLT concentrates (PCs) during storage may also be caused by cytokine gene polymorphisms, as well as WBC contamination, material that the bags are made of, and storage time, as previously described.

Prestorage leucocyte filtration of blood: effects on cytokine generation and complement activation

Each unit of whole blood normally is separated into several components before storage and transfusion. Blood contains several complex cascade systems and biologically active substances that can be activated during the processing of blood components and subsequent storage. With a transfusion, cellular components of blood and coagulation factors are transferred as desired and required. However, inflammatory mediators that may be responsible for adverse transfusion reactions are also transferred. High concentrations of cytokines, released from residual leucocytes, appear to be the cause of most febrile non-haemolytic transfusion reactions to platelet concentrates. To reduce adverse transfusion reactions, an increasing number of blood banks are introducing reduction of leucocytes in blood components before storage. Prestorage leucocyte filtration of platelet concentrates and red cells diminishes the accumulation of leucocyte-derived cytokines during storage but transfusion reactions are not eliminated. The prestorage leucoreduction of plasma has been shown to activate the complement cascade from the very beginning of storage, and complement activation and accumulation may explain some of the remaining transfusion reactions. Many severe conditions require transfusion of blood components. The clinical significance of inflammatory mediators in transfused blood products remains unclear, but it is speculated that they may have an additive and detrimental effect on the complex activated immune network in severe conditions, especially following massive transfusion.

Reduction of febrile but not allergic reactions to RBCs and platelets after conversion to universal prestorage leukoreduction.

Between January 1995 and November 1998, at Yale-New Haven Hospital, 25 percent of RBCs transfused were processed through prestorage or bedside leukoreduction filters, chosen on a per patient basis (selective leukoreduction [SLR]). Between January 1995 and July 1999, 30 percent of platelet concentrates (PCs) were infused through bedside leukoreduction filters. In an attempt to decrease febrile nonhemolytic transfusion reactions (FNHTR), a change was made from SLR to universal prestorage leukoreduction (UPL) for RBCs between November 1998 and December 1999 and for random donor PCs between July 1999 and January 2000. FNHTR and allergic transfusion reactions (ATR) reported from January 1995 through December 2002 were reviewed. For retrospective observational analysis, blood bank data were available on the number of RBCs and PCs transfused, percent products leukoreduced, and rate of FNHTR and ATR from 1995 through December 2002. After dividing this time period into three phases (SLR, transition, and UPL), these data were evaluated using odds ratio (ORs) and Student's t tests. A total of 145,369 RBCs and 137,982 PCs (29,487 PC pools) transfused between January 1995 and December 2002 were evaluated. For RBCs, the relative FNHTR rate decreased 47.1 percent, from 0.34 percent (SLR) to 0.18 percent (UPL) (p < 0.0001). ATR rates for RBCs showed 0.09 percent for both SLR and UPL groups (p > 0.05, NS). For PCs, the FNHTR relative rate decreased 93.1 percent, from 2.18 percent for SLR to 0.15 percent for UPL (p < 0.0001). Rates for ATR were 0.49 percent (SLR) and 0.35 percent (UPL) (p > 0.05, NS). A significant decrease in the frequency of posttransfusion FNHTR, but not ATR, for RBCs and PCs followed introduction of 100-percent UPL. The data support the hypothesis that the practice of UPL of RBCs and PCs decreases the frequency of FNHTR and thus improves patient care over the practice of selective leukoreduction.

The effect of prestorage WBC reduction on the rates of febrile nonhemolytic transfusion reactions to platelet concentrates and RBC.

Febrile non-hemolytic transfusion reactions (FNHTRs) are a common complication of platelet concentrate (PC) and RBC transfusions, usually ascribed to cytokines released by WBCs and perhaps the platelets themselves during storage. Prestorage WBC reduction should abrogate the accumulation of these cytokines reducing the number of FNHTRs. A retrospective analysis of FNHTR to PCs and RBCs before universal WBC reduction (PrUR) (July 1997-January 1998 for PCs, July 1997-July 1999 for RBCs) and after its introduction (PoUR) (February 1998-August 2001 for PC, August 1999-August 2001 for RBCs) was undertaken. All transfusion reactions were stratified based on component and date of reaction. Other adverse transfusion reactions were grouped into three periods: July 1997-January 1998, February 1998-July 1999, and August 1999-August 2001. A chi-square test was performed to determine the significance of the differences between groups. In the PRUR group, there were: 231 FNHTRs in 70,396 RBC units transfused (0.33%) and 29 FNHTRs in 6502 PC units transfused (0.45% percent). In the PoUR group, there were 136 FNHTRs in 72,949 RBC units transfused (0.19%, p < 0.001) and 56 FNHTRs in 50,555 PC units transfused (0.11%, p < 0.001). Of the other adverse events, only TRALI reactions were significantly reduced. Prestorage WBC reduction significantly reduced the rate of FNHTRs to PCs and RBCs.

Fetal bradycardia following intrauterine platelet transfusion: might elevated levels of donor soluble CD40 ligand play a role?

Fetal bradycardia following intrauterine platelet transfusion: might elevated levels of donor soluble CD40 ligand play a role?

Universal leukoreduction decreases the incidence of febrile nonhemolytic transfusion reactions to RBCs.

Febrile nonhemolytic transfusion reactions (FNHTR) is a relatively common complication associated with allogeneic transfusion. Because WBCs have been implicated in the mechanism of FNHTRs, it has been proposed that the transfusion of leukoreduced RBCs should be associated with a decreased incidence of FNHTRs. These reactions are generally not life threatening, but they are expensive in their management, evaluation, and associated blood-product wastage. Over the past several years, the proportion of leukoreduced RBCs has increased at Johns Hopkins Hospital in an effort to move toward complete leuko-reduction. A retrospective analysis is reported here of FNHTRs in RBC recipients as the inventory increased in percentage of leukoreduced RBC units. Between July 1994 and December 2001, all transfusion reactions (TRs) associated with the transfusion of allogeneic RBCs were retrospectively analyzed. Both computerized data and individual TR reports were reviewed. Patients who had both allergic and febrile features were included as part of both categories. TRs were reported as a percentage of total units transfused. Two time periods were selected for direct comparison. July to December 1994 represents the time period before the initiation of an increase in leuko-reduction. July to December 2001 represents a time period when almost complete leukoreduction (99.5%) had been achieved. The TR data were compared between these two time periods, comparing a time before leuko-reduction to a time period after leukoreduction had been achieved. The trends in TRs over the entire 7.5-year period of July 1994 to December 2001 were also assessed. In the initial period before the initiative to move toward leukoreduction, 96 percent of our RBC inventory was non-leukoreduced. In the study period after leukoreduction, 99.5 percent of our RBC inventory was leukoreduced. When comparing these two time periods, the incidence of FNHTRs decreased from 0.37 percent to 0.19 percent (p = 0.0008). The trend over the entire 7.5-year study period confirms the decrease in FNHTRs as the percentage of leukoreduced RBCs increased. The incidence of allergic TRs has remained unchanged over this time period. As our institution has increased its inventory of leukoreduced RBCs to approximately 100 percent, selective leukoreduced protocols have been discontinued. The incidence of FNHTRs has decreased significantly and the rate of allergic reactions has essentially remained unchanged. Leukoreduction is effective in decreasing FNHTRs associated with the transfusion of allogeneic RBCs.

ACTIVATION OF POLYMORPHONUCLEAR NEUTROPHILS BY IMMUNE COMPLEX: POSSIBLE INVOLVEMENT IN THE DEVELOPMENT OF TRANSFUSION-RELATED ACUTE LUNG INJURY

Background: Human polymorphonuclear neutrophils (PMNs) are suspected as a causative factor in the development of febrile nonhemolytic transfusion reactions (FNHTRs), such as transfusion-related acute lung injury (TRALI), although the mechanisms underlying FNHTRs have not yet been precisely clarified. The aim of this study was to evaluate the potency of immune complexes (ICs) to activate PMNs and to identify soluble factors produced by PMNs. Methods We: investigated the production of tumor necrosis factor α (TNFα) and perform by PMNs on stimulation with artificial oligomerized ICs by enzymelinked immnosorbent assay (ELISA). Furthermore, the potency of culture supernatants of PMNs that were stimulated with ICs was investigated with regard to the growth inhibitory activity against lung-tissue-derived primary cell culture (LT cells) and cytotoxic activity against LT cells by 3H-thymidine uptake experiment and 4-hour 51Cr release assay, respectively. Findings: PMNs activated by ICs were proved to produce TNFα and perform. The growth of LT cells was inhibited in the presence of cell-free culture supernatants of PMNs cultivated with ICs. Moreover, cell-free culture supernatants of PMNs cultivated with ICs appeared to have cytotoxic activity against LT cells. Conclusion: These results suggest that IC-stimulated PMNs produce inflammatory and cytotoxic mediators, which are potent inducers of FNHTRs such as TRALI.

保存前白血球除去に用いる全血用白血球除去フィルター付きクローズドバッグシステムの性能評価

In order to avoid a wide variety of side effects associated with blood transfusion such as nonhemolytic febrile transfusion reactions (NHFTR), HLA-sensitization and Cytomegalovirus infection. Leukocyte filters have come into wide use in bedside blood transfusion in Japan. During the storage of blood components, however, residual leukocytes disintegrate and release various biologically active substances, which constitute one of the causes of transfusion-related adverse events. Therefore, removal of leukocytes immediately or at an early stage after blood collection is expected to decrease the incidence of transfusion-related side effects by controlling the deterioration of blood cells or preventing the accumulation of cytokines.The WBF2 closed-bag system is a blood collection-component separation system designed for the removal of leukocytes from whole blood and the preparation of blood components by centrifugation. In the present study, we evaluated the usefulness of the system in the preparation of leukocyte-reduced RC-MAP and FFP using WBF2, and compared the quality of these preparations with those by conventional post-storage leukoreduction or non-leukoreduction. The WBF2 system yielded red cell components with superior red cell recovery and lower accumulation of some cytokines, demonstrating its suitability for use in a blood center program. It was also noted that there was almost no macroaggregation in red cell components prepared by prestorage leukoreduction.

Évaluation de la conformité à la réglementation des déclarations d’incidents transfusionnels pour frissons-hyperthermie dans des établissements de santé du sud-est de la France (groupe AIRSEH)

Febrile non-hemolytic transfusion reactions (FNHTR) are the most frequently reported acute adverse effects of blood products, and should be notified within 48 h according to the hemovigilance regulation. In order to study the conformity of these notifications and to search for factors associated with non-conformity, we retrospectively studied all FNHTR notified by voluntary centers of the AIRSEH group from 1st September 1994 to 31st December 1999. Seven hundred and sixty-one FNHTR were registered by 10 centers, most of them were benign (grade 1); 67.8% were non-conform. The non-conformity was associated with the number of biological investigations performed (median number, respectively, 4.24 and 2.94— P = 0.038—in non-conform and conform notifications— P = 0.038) in univariate analysis. Using a logistic regression model, center and severity were the only two factors significantly associated with non-conformity. Different center practices, and in particular the interface between the hospital and the blood bank, may be responsible for the effect center. Moreover, the non-conformity concerns first of all benign FNHTR. A stronger separation between alert and epidemiological surveillance is proposed in order to improve the notifications’ conformity.

Universal leucodepletion: an overview of some unresolved issues and the highlights of lessons learned

Universal leucodepletion (ULD) has been introduced in several countries based on the evidence that selective leucodepletion improves the clinical safety of blood components and based on animal studies that TSE infectivity is 5–7 times higher in the buffy coat than in plasma. Therefore it is perceivable that the removal of the buffy coat, by filtration, removing both leucocytes and platelets, may prove beneficial in reducing the potential risk of transmission of variant CJD by blood components. The implementation of a ULD policy has created some new requirements: • Validation/standardisation of various leucodepletion processes to ensure compliance with set specifications. • Standardisation/harmonisation of sampling and low leucocyte counting technologies to ensure the interchangeability of results nationally. • The establishment of external quality assessment schemes on ‘real’ leucodepleted products where the cells come in contact with the filter matrix, to monitor the low leucocyte counting performance, nationally. • Assessment of filtration-induced generation/retention of major biological response modifiers (BRM), having potential for the development of transfusion reactions. Using these approaches we have identified that, while the overall leucodepletion performance has improved following harmonisation/standardisation of the operational and counting technologies, there are still some unresolved problems and ULD alone may not provide complete protection from some viral transmission such as HTLV and CMV infections or reduction of bacterial sepsis and generation of some BRM. Moreover, ULD has not fully abrogated febrile non-haemolytic transfusion reactions (FNHTR). Therefore the key issue is not the 3–4 log 10 reduction of residual leucocytes but the design of new generation filters or leucodepletion processes with better performance characteristics, to further reduce some specific leucocyte subsets and their fragments as well as reduce the activation of coagulation/complement/kinin and inflammatory systems. Efforts should also be made to reduce the rapid development of apoptotic/necrotic cells and the residual risk associated with plasma, which often contains a vast array of BRM, responsible for residual transfusion reactions. These could only be effectively achieved by working in cooperation with the suppliers of blood component technologies. This overview briefly highlights some of the unresolved issues related to ULD, based on the experience in the UK. Technical details can be found in the reading list provided at the end.

Three years of haemovigilance in a general university hospital.

The aim of this study is to describe a newly implemented haemovigilance system in a general university hospital. We present a series of short cases, highlighting particular aspects of the reports, and an overview of all reported incidents between 1999 and 2001. Incidents related to transfusion of blood products were reported by the clinicians using a standard preformatted form, giving a synopsis of the incident. After analysis, we distinguished, on the one hand, transfusion reactions, that are transfusions which engendered signs or symptoms, and, on the other hand, the incidents where management errors and/or dysfunctions took place. Over 3 years, 233 incidents were reported, corresponding to 4.2 events for 1000 blood products delivered. Of the 233, 198 (85%) were acute transfusion reactions and 35 (15%) were management errors and/or dysfunctions. Platelet units gave rise to statistically (P < 0.001) more transfusion reactions (10.7 per thousand ) than red blood cells (3.5 per thousand ) and fresh frozen plasma (0.8 per thousand ), particularly febrile nonhaemolytic transfusion reactions and allergic reactions. A detailed analysis of some of the transfusion incident reports revealed complex deviations and/or failures of the procedures in place in the hospital, allowing the implementation of corrective and preventive measures. Thus, the haemovigilance system in place in the 'Centre Hospitalier Universitaire Vaudois, CHUV' appears to constitute an excellent instrument for monitoring the security of blood transfusion.

Hemovigilance network in France: organization and analysis of immediate transfusion incident reports from 1994 to 1998.

Hemovigilance networks have been introduced in several countries to improve knowledge of blood transfusion-related morbidity and mortality. The general organization of the French network and its results from 1994 through March 1999 are presented here. The hemovigilance network relies on blood transfusion centers and hospital correspondents, who analyze unexpected and untoward blood transfusion-related effects and transmit a Transfusion Incident Report (TIR) to a national database (Transfusion Incident Reports Electronic Data Management [GIFIT]). As of March 1, 1999, the GIFIT database contained 24,234 TIRs related to incidents that occurred from the start of the hemovigilance network until December 31, 1998. The network was not fully implemented until 1996; but the reporting rate seems to have since stabilized at approximately 7000 per year (2.5 reports per 1000 blood components). The highest reporting rate is observed with platelet concentrates (4.02/1000), followed by RBCs (1.71/1000) and FFP (0.34/1000). Bacterial contamination quickly appeared as a major cause of morbidity and mortality (185 cases and 18 fatalities). However, a general trend of reduction in this type of incident was observed over time, which can be attributed to adoption of several preventive measures. In contrast, major ABO mismatchings during RBC transfusion remained at a constant rate throughout this period and accounted for six fatalities. After the implementation of universal WBC reduction, some incidents known to be related to WBCs, such as nonhemolytic febrile transfusion reactions (NHFTR) and HLA immunization, were dramatically reduced. Hemovigilance is an important tool not only to analyze blood transfusion incidents, but also to measure the effects of new processes or corrective actions at a national level.

Inline-filtration

Background: Routine leukocyte-depletion (LD) of cellular blood products, and even plasma, is currently being implemented in most European countries, as a result of the fear that the variant Creutzfeldt-Jakob-disease (vCJD) might be transmissible by transfusion. However, not only is the scientific evidence supporting such a notion scarce, but the benefits of applying this procedure to all patients also remain unfounded. Methods: A MEDLINE-research for studies dealing with the indications for LD was performed. In addition, the guidelines and recommendations of national and international health authorities were scrutinized. Results: To date,the only proven benefit of LD that can be applied to all patients is the reduction of non-hemolytic febrile transfusion reactions. In addition, LD reduces HLA-immunization and platelet refractoriness in multi-transfused patients. In immunocompromized patients, LD reduces transfusion-transmitted CMV-disease. Furthermore, a minority of 5–10% of transfusion-related-acute-lung-injury cases can be prevented by LD. However, the potential of reducing the immunomodulating effects of transfusion such as postoperative infection, cancer-recurrence-related or overall mortality and of reducing septicemia due to bacterial contamination is still at issue. AIDS patients do not benefit from LD, at least. The suitability of LD for preventing the transmission of vCJD is at best hypothetical. Potential risks of LD like increased leakages have not been taken into account adequately to date. Conclusions: At present, the scientific evidence does not justify the introduction of LD as a routine measure. In times of limited health care resources, this costly procedure might limit access to medical services with proven effectiveness and efficiency. In addition, the loss of 5–10 % of the red cell pool is predicted to lead to more blood supply shortages than previously seen.