An adverse pulmonary reaction to cryoprecipitate in a hemophiliac

Review of current transfusion therapy and blood banking practices

Transfusion Medicine is a dynamically evolving field. Recent high-quality research has reshaped the paradigms guiding blood transfusion. As increasing evidence supports the benefit of limiting transfusion, guidelines have been developed and disseminated into clinical practice governing optimal transfusion of red cells, platelets, plasma and cryoprecipitate. Concepts ranging from transfusion thresholds to prophylactic use to maximal storage time are addressed in guidelines. Patient blood management programs have developed to implement principles of patient safety through limiting transfusion in clinical practice. Data from National Hemovigilance Surveys showing dramatic declines in blood utilization over the past decade demonstrate the practical uptake of current principles guiding patient safety. In parallel with decreasing use of traditional blood products, the development of new technologies for blood transfusion such as freeze drying and cold storage has accelerated. Approaches to policy decision making to augment blood safety have also changed. Drivers of these changes include a deeper understanding of emerging threats and adverse events based on hemovigilance, and an increasing healthcare system expectation to align blood safety decision making with approaches used in other healthcare disciplines.

Transdermal estradiol for the management of refractory uremic bleeding

PURPOSE

The efficacy and thrombogenicity of transdermal estradiol in the management of refractory uremic bleeding in adults are examined.

SUMMARY

Platelet dysfunction from chronic kidney disease may induce uremic bleeding. This type of bleeding may involve the skin, oral and nasal mucosa, gingivae, respiratory system, and gastrointestinal or urinary tract. While the mainstay of treatment for uremic bleeding primarily involves dialysis and use of prohemostatic agents such as desmopressin and erythropoiesis-stimulating agents, certain patients may experience bleeding refractory to these interventions. In this clinical scenario, a weak conditional recommendation (grade 2C) supporting transdermal estradiol as a therapy of last resort exists. Limited data suggest that transdermal estradiol may reduce bleeding time and transfusion requirements in dialysis patients with recurrent episodes of hematochezia, gastrointestinal telangiectasia, and hematomas. The management of uremic bleeding will require long-term therapy, and case reports have documented the safe use of transdermal estradiol for up to 25 months. Oral conjugated estrogens increase the risk of deep vein thrombosis in women; however, the transdermal route of administration has been associated with a lower incidence of venous thromboembolism and stroke relative to oral estrogen and, in some studies, its associated risk of thrombosis is not significantly different when compared with placebo.

CONCLUSION

Patients who are refractory to routine interventions for uremic bleeding may benefit from transdermal estrogen despite the limited data. Extended therapy with low-dose transdermal estrogen (≤50 μg daily) may provide a hemostatic benefit that outweighs thrombotic risk.

The impact of leukoreduced red blood cell transfusion on mortality of neonates undergoing extracorporeal membrane oxygenation

BACKGROUND

Blood products containing leukocytes have been associated with negative immunomodulatory and infectious effects. Transfusion-related acute lung injury is partially explained by leucocyte agglutination. The Food and Drug Administration has therefore recommended leukoreduction strategies for blood product transfusion. Our institution has been using leukocyte-reduced blood via filtration for neonates on Extracorporeal Membrane Oxygenation (ECMO). We hypothesized that the use of leukocyte-reduced blood would decrease mortality and morbidity of neonatal ECMO patients.

METHODS

Retrospective review of noncardiac ECMO in neonates from 1984-2011, stratified into year groups I and II (≤1996 and ≥1997). Demographics, duration and type of ECMO, complications, and outcome data were collected. Blood product use data was collected. Univariate, bivariate, and multivariate analyses determined predictors of risk-adjusted mortality by year group.

RESULTS

Patients (827) underwent ECMO with 65.3% (540) in group I. Overall median blood product use in mL/kg/d was 36.2 packed red blood cells (pRBC), 8.1 platelets, and 0 cyroprecipitate and/or fresh-frozen plasma. Overall mortality was 16.4%. Median pRBC used or transfused was 42.1 mL/kg/d in group I versus 19.1 mL/kg/d group II (P <0.001). On bivariate analysis, there was no difference in crude mortality between the 2 year groups (17.2% versus 16.0%, P = 0.66). However, on multivariate analysis adjusting for demographics, diagnosis, complications, and blood product use other than pRBCs, each additional transfusion of 10 mL/kg/d of pRBC was associated with a 33% increase in mortality in group I (P <0.05). Group II also showed an increase in mortality with each additional transfusion (21%) but this was not statistically significant (P = 0.07). Days on ECMO were not associated with pRBC transfusion in group I but increased in group II (additional 3 d for each 10 mL/kg/d transfused). There was no difference in infectious complications between groups I and II.

CONCLUSIONS

Blood transfusion requirement has diminished in newborns undergoing ECMO at our institution. Transfusion of non leukocyte-reduced blood is associated with an increase in mortality whereas transfusion of leukocyte-reduced blood provided no benefit with a trend toward increased mortality. Further research is recommended to understand these trends.

Pulmonary complications of transfused blood components

Three transfusion complications are responsible for the majority of the morbidity and mortality in hospitalized patients. This article discusses the respiratory complications associated with these pathophysiologic processes, including definitions, diagnosis, mechanism, incidence, risk factors, clinical management, and strategies for prevention. It also explores how different patient populations and different blood components differentially affect the risk of these deadly transfusion complications. Lastly, the article discusses how health care providers can risk stratify individual patients or patient populations to determine whether a given transfusion is more likely to benefit or harm the patient based on the transfusion indication, risk, and expected result.

Red blood cell transfusion in the neurological ICU

Red blood cell transfusion (RBCT) is a common therapy used in the intensive care unit to treat anemia. However, due to deleterious side effects and questionable efficacy, the clinical benefit of RBCT in patients who are not actively bleeding is unclear. The results of randomized controlled trials suggest there is no benefit to a liberal transfusion practice in general critical care populations. Whether the results of these trials are applicable to brain injured patients is unknown, as patients with primary neurological injury were excluded. This article reviews the efficacy and complications of RBCT, as well as the relationship between RBCT and its outcome in both the general intensive care unit and neurologically critically ill populations.

Transfusion therapy and acute lung injury

Transfusion-related acute lung injury (TRALI) remains the deadliest complication of transfusion. Consensus definitions of TRALI have been developed but remain controversial. Recent evidence supports a strong relationship between blood transfusion and the development of acute lung injury in the critically ill and trauma population. Plasma and platelet transfusions have been the most commonly implicated blood products. The 'two hit' model may best explain the immune and nonimmune pathogenesis of TRALI. Current treatment remains largely supportive; effective measures for decreasing the incidence of TRALI include the use of predominantly male plasma and apheresis platelets. Greater understanding of the blood component and patient risk factors for TRALI will hopefully lead to novel treatment and preventive strategies for reducing the risk of this life-threatening syndrome.

Cryoprecipitate: no longer the best therapeutic choice in congenital fibrinogen disorders?

Congenital abnormalities of fibrinogen are rare disorders classified as quantitative (afibrinogenemia and hypofibrinogenemia) or qualitative types (dysfibrinogenemia and hypodysfibrinogenemia). Fibrinogen is essential to haemostasis as the substrate for fibrin clot formation and also acts in primary haemostasis as a key ligand in platelet aggregation. Quantitative deficiency of fibrinogen can result in severe bleeding, or arterial and venous thromboembolism, and poor wound healing. Dysfibrinogenemia is characterized by functional abnormalities of fibrinogen, which may be asymptomatic (in 50% of cases), or cause bleeding (25%) or thrombosis (25%). Replacement of the deficient or abnormal fibrinogen with frozen plasma, cryoprecipitate, or fibrinogen concentrate has been found to be effective in practice in treating haemostatic complications of these disorders. Although cryoprecipitate is the most commonly used replacement material, pathogen-reduced fibrinogen concentrates have several advantages, most importantly a lower potential risk of viral transmission and standardized fibrinogen content allowing accurate dosing. They also avoid transfusing unwanted clotting factors, platelet microparticles and immunoglobulins, and can be administered rapidly without thawing. The use of fibrinogen concentrate to treat congenital fibrinogen disorders is strongly supported in principle and increasingly by practical experience and evidence.

Use of human protein C concentrates in the treatment of patients with severe congenital protein C deficiency

Protein C is one of the major inhibitors of the coagulation system that downregulate thrombin generation. Severe congenital protein C deficiency leads to a hypercoagulability state that usually presents at birth with purpura fulminans and/or severe venous and arterial thrombosis. Recurrent thrombotic events are commonly seen. From the 1990’s, several virus-inactivated human protein C concentrates have been developed. These concentrates currently constitute the therapy of choice for the treatment and prevention of clinical manifestations of severe congenital protein C deficiency. This review summarizes the available information on the use of human protein C concentrates in patients with severe congenital protein C deficiency.

TRALI is due to pulmonary venule damage from leucocytes with cholesterol crystal formation

BACKGROUND

There are two presumed mechanisms for the pulmonary oedema in transfusion-related acute lung injury (TRALI). One is antibodies to leucocytes while the other is biologically active lipids. We evaluated the vascular injury due to the former.

METHODS

The pulmonary vasculature was studied by light microscopy (LM) and scanning electron microscopy (SEM) in three fatal cases of TRALI and compared with that of two autopsied control patients. Lung tissue from two of the TRALI cases and both controls was studied by gas chromatography-mass spectroscopy (GC-MS) to identify crystals present in the former.

RESULTS

All three TRALI cases exhibited massive pulmonary oedema by weight and light microscopy and extensive defects by SEM in the endothelium of venules of the lungs. Such endothelial defects were absent in controls. Thrombi, composed of crystals, were present in venules and small veins diffusely throughout the lungs in Case 1. Similar crystals were identified in Case 2. The crystals in the lung vessels were identified morphologically as cholesterol and were proximate to the cytoplasmic defects of the endothelial surfaces. By GC-MS, there were markedly elevated levels of cholesterol and fatty acids in the two TRALI lungs tested compared with the lungs of the two controls.

CONCLUSIONS

Pulmonary damage in TRALI is related to formation of cholesterol crystals that appear to pierce endothelial membranes of venules. The endothelial defects lead to plasma extravasation into the alveoli causing TRALI.

Transfusion-related acute lung injury (TRALI): a clinical review with emphasis on the critically ill

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related morbidity and mortality world-wide. Although first described in 1983, it took two decades to develop consensus definitions, which remain controversial. The pathogenesis of TRALI is related to the infusion of donor antibodies that recognize leucocyte antigens in the transfused host or the infusion of lipids and other biological response modifiers that accumulate during the storage or processing of blood components. TRALI appears to be the result of at least two sequential events and treatment is supportive. This review demonstrates that critically ill patients are more susceptible to TRALI and require special attention by critical care specialists, haematologists and transfusion medicine experts. Further research is required into TRALI and its pathogenesis so that transfusions are safer and administered appropriately. Avoidance including male-only transfusion practises, the use of leucoreduced components, fresher blood/blood components and solvent detergent plasma are also discussed.

Transfusion-related acute lung injury: a literature review

Transfusion-related acute lung injury (TRALI) is a serious and potentially fatal complication of transfusion of blood and blood components. TRALI is under-diagnosed and under-reported because of a lack of awareness. A number of models have been proposed to explain the pathogenesis of TRALI: an antibody mediated model; a two-event biologically active mediator model; and a combined model. TRALI can occur with any type of blood product and can occur with as little as one unit. Its presentation is similar to other forms of acute lung injury and management is predominantly supportive. The main strategy in combating TRALI is prevention both through manipulation of the donor pool and through clinical strategies directed at reducing transfusion of blood products including, but not limited to, evidence-based lower transfusion thresholds. This article presents a review of TRALI and addresses the definition, pathology, pathogenesis, clinical manifestations, treatment and prevention of the syndrome.

Transfusion-Related Acute Lung Injury (TRALI): Current Clinical and Pathophysiologic Considerations

Transfusion-related acute lung injury (TRALI) is a rare transfusion reaction presenting as respiratory distress during or after transfusion of blood products. TRALI varies in severity, and mortality is not uncommon. TRALI reactions have equal gender distributions and can occur in all age groups. All blood products, except albumin, have been implicated in TRALI reactions. TRALI presents as acute respiratory compromise occurring in temporal proximity to a transfusion of a blood product. Other causes of acute lung injury should be excluded in order to definitively diagnose TRALI. Clinically and pathologically, TRALI mimics acute respiratory distress syndrome (ARDS), with neutrophil-derived inflammatory chemokines and cytokines believed to be involved in the pathogenesis of both entities. Anti-HLA and anti-neutrophil antibodies have been implicated in some cases of TRALI. Treatment for TRALI is supportive; prevention is important. It is suspected that TRALI is both underdiagnosed and underreported. One of the difficulties in the evaluation of potential TRALI reactions is, until recently, the lack of diagnostic criteria. A group of transfusion medicine experts, the American-European Consensus Conference (AECC), recently met and developed diagnostic criteria of TRALI, as well as recommendations for management of donors to prevent future TRALI reactions. In light of the AECC consensus recommendations, we report an incident of TRALI in an oncology patient as an example of the potential severity of the lung disease and the clinical and laboratory evaluation of the patient. We also review the literature on this important complication of blood transfusion that internists may encounter.

Understanding the Consequences of Transfusion-Related Acute Lung Injury

Although the blood supply has become safer with regard to transmission of infectious agents, attention should continue to focus on understanding and eliminating the other serious risks associated with transfusion. Transfusion-related acute lung injury (TRALI) is one such risk, only recently becoming recognized as an important and potentially preventable clinical syndrome. Strategies for prevention of TRALI, however, must rely on knowledge regarding its etiology and diagnosis, and significant gaps in our understanding of the syndrome currently exist. This review summarizes what is known and unknown about the incidence, severity, etiology, diagnosis, and prevention of TRALI and the potential consequences of these knowledge gaps.

Transfusion-related acute lung injury (TRALI): a serious adverse event of blood transfusion

BACKGROUND AND OBJECTIVES

Analyses of fatal transfusion reactions in the UK and USA have shown that transfusion-related acute lung injury (TRALI) is among the most common causes of fatal transfusion reactions.

MATERIAL AND METHODS

Review of the literature was used to analyse TRALI.

RESULTS

TRALI is characterized by acute respiratory distress and non-cardiogenic lung oedema developing during, or within 6 h of, transfusion. In atypical cases, TRALI can become symptomatic much later. TRALI must be carefully differentiated from transfusion-associated circulatory overload. In its fulminant presentation, TRALI can be clinically indistinguishable from acute respiratory distress syndrome occurring as a result of other causes. The severity of TRALI depends upon the susceptibility of the patient to develop a more clinically significant reaction as a result of an underlying disease process, and upon the nature of triggers in the transfused blood components, including granulocyte-binding alloantibodies (immune TRALI) or neutrophil-priming substances such as biologically active lipids (non-immune TRALI). Immune TRALI, which occurs mainly after the transfusion of fresh-frozen plasma and platelet concentrates, is a rare event (about one incidence per 5000 transfusions) but frequently ( approximately 70%) requires mechanical ventilation (severe TRALI) and is not uncommonly fatal (6-9% of cases). Non-immune TRALI, which occurs mainly after the transfusion of stored platelet and erythrocyte concentrates, seems to be characterized by a more benign clinical course, with oxygen support sufficient as a form of therapy in most cases, and a lower mortality than immune TRALI.

CONCLUSIONS

By virtue of its morbidity and mortality, TRALI has become one of the most serious current complications of transfusion. To prevent further antibody-mediated cases, the evaluation of TRALI should include leucocyte antibody testing of implicated donors. However, further studies are necessary for the prevention of this serious transfusion complication.

White blood cell-reactive antibodies are undetectable in solvent/detergent plasma

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a life-threatening complication of transfusion. Although all types of blood products have been associated with TRALI, fresh-frozen plasma (FFP) is the most commonly implicated component. It has been postulated that TRALI is an immune-mediated event, because white blood cell (WBC)-reactive antibodies in the donor's plasma are frequently associated with the syndrome. In contrast to single donor-derived FFP, solvent/detergent (S/D) plasma is produced from multiple donations, leading to an at least 500-fold dilution of a single plasma unit. It was hypothesized that WBC-reactive antibodies are undetectable in S/D FFP.

STUDY DESIGN AND METHODS

Twenty batches of S/D FFP (5 of each ABH group) were analyzed with well-established routine techniques to detect WBC antibodies.

RESULTS

All samples tested negative for granulocyte-specific as well as HLA Class I and Class II antibodies.

CONCLUSIONS

Different strategies to reduce the risk of TRALI are currently discussed. These include screening of all potentially immunized donors for WBC-reactive antibodies and exclusion of multiparous or all women from donating FFP. Here, it is demonstrated that neither granulocyte- nor lymphocyte-reactive antibodies are detectable in S/D FFP. Thus, S/D FFP may represent a potential alternative to reduce the risk of TRALI associated with the transfusion of FFP.

Transfusion related acute lung injury: a pediatric perspective

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-associated mortality. TRALI occurs in children and adults, but the syndrome has not been reviewed from a pediatric perspective. We reviewed the literature on TRALI from a pediatric perspective. TRALI has been documented in pediatric patients, especially in the setting of hematologic malignancy. Additional TRALI cases have been reported in pediatric patients with a variety of diagnoses. TRALI is likely to be much more common than previously appreciated in the pediatric patient population. TRALI should be considered in the differential diagnosis of all pediatric patients who develop new acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) during or within six hours of a blood product transfusion. When a case of TRALI is suspected, a transfusion reaction report to the blood bank is important to initiate the investigation and identify the implicated donor.

Transfusion-related acute lung injury

Transfusion-related acute lung injury (TRALI) is characterized by the sudden development of noncardlogenic pulmonary edema (acute lung Injury) after transfusion of blood products. Poor awareness of TRALI outside of the blood transfusion medicine community has led to a serious underestimation of this condition, currently the most Important severe complication of blood transfusion. Concern for the transfer of donor antileukocyte antibodies has prompted major changes in the management of the blood supply in some countries; however, recent studies have suggested alternative pathophyslological mechanisms for TRALI related to the shelf life of cellular blood products. Although all blood products have been implicated, most reported cases were associated with fresh frozen plasma, red blood cell, and platelet transfusions. Because many patients have additional predisposing factors for acute lung injury, carefully designed prospective studies are needed to fully assess attributable risk related to transfusion. The treatment of TRALI is supportive, and the prognosis is generally better than for other causes of acute lung Injury. As many as one third of all patients who develop acute lung injury have been exposed to blood products. TRALI may be an important and potentially preventable cause of acute lung injury.

Transfusion-related acute lung injury

Transfusion-related acute lung injury (TRALI) is characterized by the sudden development of noncardlogenic pulmonary edema (acute lung Injury) after transfusion of blood products. Poor awareness of TRALI outside of the blood transfusion medicine community has led to a serious underestimation of this condition, currently the most Important severe complication of blood transfusion. Concern for the transfer of donor antileukocyte antibodies has prompted major changes in the management of the blood supply in some countries; however, recent studies have suggested alternative pathophyslological mechanisms for TRALI related to the shelf life of cellular blood products. Although all blood products have been implicated, most reported cases were associated with fresh frozen plasma, red blood cell, and platelet transfusions. Because many patients have additional predisposing factors for acute lung injury, carefully designed prospective studies are needed to fully assess attributable risk related to transfusion. The treatment of TRALI is supportive, and the prognosis is generally better than for other causes of acute lung Injury. As many as one third of all patients who develop acute lung injury have been exposed to blood products. TRALI may be an important and potentially preventable cause of acute lung injury.

Transfusion-related acute lung injury: a review

Transfusion-related acute lung injury (TRALI) is an underreported complication of transfusion therapy, and it is the third most common cause of transfusion-associated death. TRALI is defined as noncardiogenic pulmonary edema temporally related to transfusion therapy. The diagnosis of TRALI relies on excluding other diagnoses such as sepsis, volume overload, and cardiogenic pulmonary edema. Supportive diagnostic evidence includes identifying neutrophil or human leukocyte antigen (HLA) antibodies in the donor or recipient plasma. All plasma-containing blood products have been implicated in TRALI, with the majority of cases linked to whole blood, packed RBCs, platelets, and fresh-frozen plasma. The pathogenesis of TRALI may be explained by a "two-hit" hypothesis, with the first "hit" being a predisposing inflammatory condition commonly present in the operating room or ICU. The second hit may involve the passive transfer of neutrophil or HLA antibodies from the donor or the transfusion of biologically active lipids from older, cellular blood products. Treatment is supportive, with a prognosis substantially better than most causes of clinical acute lung injury.

Transfusion-related acute lung injury (TRALI) following allogeneic stem cell transplant for acute myeloid leukemia

Transfusion-related acute lung injury (TRALI) is a serious complication of transfusion characterized by dyspnea, hypoxemia, hypotension, fever, and bilateral pulmonary infiltrates. Although the frequency is estimated at 1/1,120 to 1/5,000 transfusions, few cases have been reported after hematopoietic stem cell transplant. We report a case occurring in an allogeneic transplant recipient who developed acute respiratory distress and bilateral pulmonary infiltrates 2 hr after a platelet transfusion due to the presence of anti granulocyte antibody HNA-3a in the product. As there is a wide differential diagnosis for pulmonary infiltrates developing post transplant, TRALI may be under-recognized and should be considered in this setting.

Transfusion-related acute lung injury

Transfusion-related acute lung injury (TRALI) is an uncommon complication of allogeneic blood transfusion manifested typically by shortness of breath, fever, and hypotension. It has been estimated to occur in 0.04% to 0.16% per patient transfused. TRALI has been identified as an important cause of transfusion-related morbidity and mortality. Despite the increasing recognition that TRALI represents an important clinical syndrome, much about the pathogenesis, treatment, and prevention of TRALI is poorly understood or is controversial. In this report, what is known about TRALI is summarized and some of the areas in which knowledge and/or consensus are currently lacking are identified.

Transfusion-related acute lung injury during plasma exchange: Suspecting the unsuspected

Transfusion-related acute lung injury (TRALI) has been implicated with use of almost all types of blood products that contain variable amounts of plasma. Even though the reported incidence of TRALI is rare, its overall occurrence is thought to be more common, as less severe cases remain unreported. More TRALI cases are unrecognized and misdiagnosed due to lack of suspicion and absence of appropriate investigation. There are exceedingly rare reports of TRALI during plasma exchange despite the fact that liters of plasma may be used for replacement during a single procedure. We describe a mild case of TRALI during plasma exchange for thrombotic thrombocytopenic purpura in a 56-year-old woman, status post autologous hematopoietic stem cell transplant for non-Hodgkin's lymphoma. She developed severe rigors, peripheral cyanosis, hypoxia, and a transient diffuse pulmonary infiltrate. Of the 10 U of plasma used, one was from a multiparous female donor with HLA antibodies reactive with patient's granulocytes in immunofluorescence and agglutination assays. This case emphasizes the fact that the physicians and apheresis staff should consider TRALI in the differential diagnosis for patients developing respiratory distress during or soon after the procedure. Diagnosing TRALI has implications not only for the plasma exchange recipient, but also for the management of donors found to have leukocyte antibodies.

Investigating transfusion-related acute lung injury (TRALI)

AIM

Transfusion-related acute lung injury (TRALI) can be a life-threatening transfusion complication and should be considered whenever respiratory distress occurs during a transfusion. Management of donors implicated in TRALI is a n important haemovigilance responsibility for blood services. To enable this, it is imperative to develop an effective strategy for investigating TRALI. The present paper describes an effective approach.

METHODS

Cases of suspected TRALI we re referred to the Platelet and Granulocyte Immunobiology Laboratory at the Australian Red Cross Blood Service-Queensland; a reference neutrophil testing service. Recipient and donor samples were tested for the presence of leucocyte antibodies. Where possible, compatibility testing was performed between donor and recipient samples.

RESULTS

From March 1999 to June 2001 , leucocyte antibodies directed against neutrophil-specific or human leucocyte antigens (HIA) were detected in at least one donor in seven of the nine cases investigated. Incompatibility with patient antigens (HNA-2a, non-specific HLA and HLA B5, B16, B35) was confirmed by cross matching in three cases.

CONCLUSION

TRALI is a serious non-infectious hazard of transfusion that must be reported and investigated promptly. Prompt investigations allow appropriate management of implicated donations and donors so as to minimize the incidence of TRALI. Therefore, the role of clinicians in reporting such cases and the hospital blood banks in collecting appropriate samples is critical. We suggest that hospital blood banks retain transfused donation units for at least 24 h after transfusion to expedite TRALI investigations. Due to the specialized nature of investigation, it is necessary to direct such investigations to specialist reference neutrophil testing services. In cases where the recipient has the leucocyte antibody, the use of white cell filters in future transfusions should be beneficial, because there is little evidence to substantiate the use of phenotyped blood products.

Breathlessness and blood: a combustible combination

Pulmonary complications are increasingly recognized as serous hazards of transfusion. The evidence suggests that transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are underrecognized. Both present with dyspnea but other signs and symptoms assist in determining the proper diagnosis. Males and females are equally affected. Morbidity is significant with both complications and in the case of TRALI, the mortality is in the range of 6-10%. Although the clinical descriptions of both entities are well established, the clinical profile of the at-risk population for both TRALI and TACO is not well understood. Because early intervention can reduce morbidity, it is important that clinicians recognize these disorders and apply appropriate treatment.

HLA class II antibodies in transfusion-related acute lung injury

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a serious, sometimes fatal, complication of transfusion. Granulocyte and HLA class I antibodies present in blood donors have been associated with TRALI. HLA class II antibodies have recently been described in a few cases of TRALI.

STUDY DESIGN AND METHODS

Donors involved in TRALI reactions reported to a blood center over an 18-month period were tested for HLA class I and II antibodies as well as granulocyte antibodies, if HLA antibodies were not identified.

RESULTS

HLA class II antibodies were identified, in at least one donor, in 7 (64%) of 11 cases of TRALI. HLA class I antibodies were identified in combination with HLA class II antibodies in 5 of these 7 cases. HLA class I antibodies were exclusively identified in 2 cases. Granulocyte antibodies were identified in 1 case, and no antibodies were identified in another.

CONCLUSION

In addition to HLA class I antibodies, HLA class II antibodies are associated with TRALI. Testing of donors for HLA class II antibodies as well as HLA class I and granulocyte antibodies is recommended as part of the investigation of suspected cases of TRALI.

Transfusion-related acute lung injury secondary to biologically active mediators

Transfusion-related acute lung injury is seen following the transfusion of blood components. The reported incidence is approximately 1 in 2000 transfusions. Clinically, it is similar to adult respiratory distress syndrome. The pathophysiology is unclear but has been attributed to HLA antibodies, granulocyte antibodies, and more recently to biologically active mediators in stored blood components. We report a case with laboratory evidence that supports the role of biologically active mediators in the pathogenesis of transfusion-related acute lung injury. To our knowledge, the case reported here is the first to use lipid extractions of patient samples to determine that lipid-priming activity was present at the time transfusion-related acute lung injury was identified clinically.

Transfusion-related acute lung injury

Transfusion-related acute lung injury is a life-threatening complication of hemotherapy associated with the transfusion of plasma-containing blood products. It is characterized by acute respiratory distress, pulmonary edema and hypoxemia. Although its frequency is unknown, Food and Drug Administration data suggest that it is the third most common cause of transfusion-associated deaths, representing 9% of reported cases. Males and females of all ages are at equal risk. To date, there is no recognized profile of individuals who are at increased risk for this complication. Although there are two purported mechanisms of injury, the preponderance of evidence suggests that passively transfused complement-activating antibodies (either granulocyte or HLA-specific) act as mediators, which result in granulocyte aggregation, activation, and microvascular pulmonary injury. With appropriate respiratory intervention, most patients recover within 96 hours of the original insult and without permanent pulmonary sequelae.

Transfusion-related acute lung injury (TRALI) following autologous stem cell transplant for relapsed acute myeloid leukaemia: a case report and review of the literature

A fatal case of transfusion-related acute lung injury (TRALI) in a child post-autologous stem cell transplant for relapsed acute myeloid leukaemia is described. The implicated product was a single unit platelet concentrate containing anti-HLA A2 and granulocyte-specific anti-NA1 antibodies. The recipient typed as HLA A2/A2, NA1/NA1. This is the first reported case of TRALI following a transplant procedure for a haematological condition. It is also unusual in that the patient failed to make a full recovery and that two relevant leucocyte antibodies of clear specificity were identified in the donor plasma. The literature relating to the pathophysiology, clinical sequelae and management of TRALI is reviewed.

Some complications of the therapy of hemorrhagic disorders

The principal mode for treating disorders of hemostasis is correction of the patient's functional defect by transfusions of appropriate fractions of normal plasma or transfusions of platelets. Two major complications of such therapy are the transmission of infectious diseases, particularly hepatitis and the acquired immune deficiency syndrome (AIDS), and the development of antibodies against clotting factors that are deficient in the patient's plasma. Measures that reduce the occurrence of infection include careful selection of donors, fractionation of plasma with the help of monoclonal antibodies, and treatment of plasma or its fractions with heat or with virus-inactivating organic solvents. No technique of preparing or administering blood or its components can prevent the emergence of antibodies against clotting factors. Desensitization by repeated infusions of antigen, for example, antihemophilic factor, however, appears to result in remission in some patients.

von Willebrand factor characterization of a severe dry-heat treated factor VIII concentrate, AHF (high purity)

Eight batches of a severe dry-heat treated (80 degrees C for 72 hours) Factor VIII concentrate manufactured by the Commonwealth Serum Laboratories (CSL Ltd.) were analysed for the following von Willebrand factor-related (vWf) activities: ristocetin cofactor activity (vWf:RCof), collagen binding activity (CBA), vWf antigen levels (vWf:Ag), vWf multimeric analysis and 2-stage FVIII clotting activity (VIII:C). The average potency per vial of vWf:Ag was 440 +/- 80 units, vWf:RCof 500 +/- 60 units, CBA 350 +/- 50 units and VIII:C 242 +/- 36 International Units. Multimeric analysis indicated the presence of high molecular weight multimers and a triplet structure slightly different to normal plasma. Viral inactivation studies using a marker virus, Sindbis, demonstrated that the terminal severe dry- heating step reduced the viral load in the product by greater than 6 log10TCID50/ml. This CSL Ltd. FVIII concentrate may thus provide a safer, purer and more convenient source of vWf than cryoprecipitate. Clinical studies to establish product efficacy in patients with von Willebrand's disease are underway.