Guidelines on the use of irradiated blood components

Transfusion-induced HLA sensitization in wait-list patients and kidney transplant recipients

Human leukocyte antigen (HLA) sensitization remains an impediment to successful solid organ transplantation, whether it be chances of receiving a transplant offer or subsequent transplant longevity. Current treatments targeting HLA antibodies lack long-term effectiveness; therefore, preventing HLA sensitization should remain a priority in all potential wait-list candidates and transplant recipients. Recent advances in the management of anemia in patients with chronic kidney disease may reduce the need for red cell transfusions. However, data from several anemia intervention studies of novel therapeutic agents have shown that a need for transfusion will remain. It has also been increasingly recognized that blood transfusions following kidney transplantation, especially in the peri-operative period, are common. Routine data on transfusion incidence, indications, and outcomes are not captured by most kidney and transplant registries across the globe. This restricts the evidence to inform both clinicians and patients on the clinical effects of transfusion, which have been considered both an allogeneic stimulus and to be immunomodulatory.This review aims to provide an update on what is currently known about transfusion-induced HLA sensitization in wait-list candidates and transplant recipients, summarizes where evidence is lacking, and demonstrates the distinct need for patient blood management guidelines in the field of kidney transplantation.

Universal irradiation of platelets: Does irradiation affect the quality, effectiveness, and safety of platelets for transfusion?

We aimed to identify any detrimental effects on platelet quality and clinical effectiveness, of irradiated platelets compared to non-irradiated platelets for transfusion. The review was conducted in accordance with PRISMA guidelines. The protocol was prospectively registered on PROSPERO [CRD42023441930]. Our search identified 3002 references, of which we included 44 studies. Forty-one were in vitro only studies, two studies were in healthy volunteers, and one study reported clinical outcomes in thrombocytopenic patients. X-ray was used exclusively in three studies, and alongside gamma irradiation in one study. Two studies did not report the source of irradiation. The remaining 38 studies used gamma irradiation only. We assessed risk of bias (ROB) for studies reporting clinical and in vivo outcomes using ROB 2.0 (3 studies). We adapted a ROB tool designed for animal studies to assess ROB for the studies reporting in vitro outcomes (43 studies). We assessed the certainty of the evidence for the eight outcomes deemed most important to assess platelet quality and clinical effectiveness (where day 0 is the day of the blood draw). Overall, gamma irradiation has little to no effect on most markers of platelet quality and effectiveness. Where there is evidence of detriment from irradiation, differences are small in vitro, and are unlikely to affect clinical outcomes following transfusion. However, the evidence base is limited. Only half the studies could be included in any analysis. There is very limited evidence for x-ray as a source of irradiation and, given the potential benefits of using x-ray over gamma irradiation (ease of use and safety requirements), we would welcome further research comparing x-ray to gamma, and x-ray to a non-irradiated control.

Transfusion of blood components in pediatric age groups: an evidence-based clinical practice guideline adapted for the use in Egypt using 'Adapted ADAPTE'

Pediatric transfusion is a complex area of medicine covering a wide age range, from neonates to young adults. Compared to adult practice, there is a relative lack of high-quality research to inform evidence-based guidelines. We aimed to adapt the pre-existing high-quality practice guidelines for the transfusion of blood components in different pediatric age groups to be available for national use by general practitioners, pediatricians, and other health care professionals. The guideline panel included 17 key leaders from different Egyptian institutions. The panel used the Adapted ADAPTE methodology. The panel prioritized the health questions and recommendations according to their importance for clinicians and patients. The procedure included searching for existing guidelines, quality appraisal, and adaptation of the recommendations to the target context of use. The guideline covered all important aspects of the indications, dosing, and administration of packed red cells, platelets, and fresh frozen plasma. It also included transfusion in special situations, e.g., chronic hemolytic anemia and aplastic anemia, management of massive blood loss, malignancies, surgery, recommendations for safe transfusion practices, and recommendations for modifications of cellular blood components. The final version of the adapted clinical practice guideline (CPG) has been made after a thorough review by an external review panel and was guided by their official recommendations and modifications. A set of implementation tools included algorithms, tables, and flow charts to aid decision-making in practice. This adapted guideline serves as a tool for safe transfusion practices in different pediatric age groups.

Transfusion Support in Hematopoietic Stem Cell Transplantation: A Contemporary Narrative Review

Hematopoietic stem cell transplantation (HSCT) is a cornerstone of modern medical practice, and can only be performed safely and effectively with appropriate transfusion medicine support. Patients undergoing HSCT often develop therapy-related cytopenia, necessitating differing blood product requirements in the pre-, peri-, and post-transplant periods. Moreover, ensuring optimal management for patients alloimmunized to human leukocyte antigens (HLA) and/or red blood cell (RBC) antigens, as well as for patients receiving ABO-incompatible transplants, requires close collaboration with transfusion medicine and blood bank professionals. Finally, as updated transfusion guidelines and novel blood product modifications emerge, the options available to the transplant practitioner continue to expand. Herein, we detail contemporary blood transfusion and transfusion medicine practices for patients undergoing HSCT.

Guidelines for the diagnosis and management of adult aplastic anaemia: A British Society for Haematology Guideline

Pancytopenia with hypocellular bone marrow is the hallmark of aplastic anaemia (AA) and the diagnosis is confirmed after careful evaluation, following exclusion of alternate diagnosis including hypoplastic myelodysplastic syndromes. Emerging use of molecular cyto-genomics is helpful in delineating immune mediated AA from inherited bone marrow failures (IBMF). Camitta criteria is used to assess disease severity, which along with age and availability of human leucocyte antigen compatible donor are determinants for therapeutic decisions. Supportive care with blood and platelet transfusion support, along with anti-microbial prophylaxis and prompt management of opportunistic infections remain key throughout the disease course. The standard first-line treatment for newly diagnosed acquired severe/very severe AA patients is horse anti-thymocyte globulin and ciclosporin-based immunosuppressive therapy (IST) with eltrombopag or allogeneic haemopoietic stem cell transplant (HSCT) from a matched sibling donor. Unrelated donor HSCT in adults should be considered after lack of response to IST, and up front for young adults with severe infections and a readily available matched unrelated donor. Management of IBMF, AA in pregnancy and in elderly require special attention. In view of the rarity of AA and complexity of management, appropriate discussion in multidisciplinary meetings and involvement of expert centres is strongly recommended to improve patient outcomes.

Hematopoiesis and immune reconstitution after CD19 directed chimeric antigen receptor T-cells (CAR-T): A comprehensive review on incidence, risk factors and current management

Impaired function of hematopoiesis after treatment with chimeric antigen T-cells (CAR-T) is a frequent finding and can interest a wide range of patients, regardless of age and underlying disease. Trilinear cytopenias, as well as hypogammaglobulinemia, B-cell aplasia, and T-cell impairment, can severely affect the infectious risk of CAR-T recipients, as well as their quality of life. In this review, we provide an overview of defects in hematopoiesis after CAR-T, starting with a summary of different definitions and thresholds. We then move to summarize the main pathogenetic mechanisms of cytopenias, and we offer insight into cytomorphological aspects, the role of clonal hematopoiesis, and the risk of secondary myeloid malignancies. Subsequently, we expose the major findings and reports on T-cell and B-cell quantitative and functional impairment after CAR-T. Finally, we provide an overview of current recommendations and leading experiences regarding the management of cytopenias and defective B- and T-cell function.

Vesiculation in irradiated and cation-leaky-stored red blood cells

BACKGROUND

Extracellular vesicles (EVs) are released by red blood cells (RBCs) throughout their life-span and also during hypothermic storage when they accumulate in the blood bag. We queried whether stored RBCs with increased cation permeability, either from donors with familial pseudohyperkalaemia (FP) or caused by irradiation, vesiculate more readily.

STUDY DESIGN AND METHODS

Recent technical advances have revealed at least two sub-populations of MVs in RBC storage units: macrovesicles (2-6 μm) and microvesicles (1-2 μm). Using nanoparticle tracking analysis, imaging flow cytometry, and protein quantification methods, we measured and characterized vesicles released by RBCs from control and FP individuals at three different storage time-points (day 4, day 17, and day 29). The RBCs had either been stored untreated or irradiated on either day 1 or day 14 of storage.

RESULTS

We found no difference in the number or size of vesicles released between cation-leaky FP RBCs and non-FP controls. Similarly, irradiated and non-irradiated RBCs showed very similar patterns of vesicle release to during cold-storage. The only significant difference in vesicle release was the increase in accumulated vesicles with length of storage time which has been reported previously.

DISCUSSION

EVs in stored blood are potential contributors to adverse transfusion reactions. The number of vesicles released during 35-day hypothermic storage varies between donors and increases with storage duration. However, increased cation permeability and irradiation do not appear to affect vesicle formation during RBC cold-storage.

Long-term survivorship care after CAR-T cell therapy

While cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome are well-recognized acute toxicities of chimeric antigen receptor (CAR) T cell therapy, these complications have become increasingly manageable by protocolized treatment algorithms incorporating the early administration of tocilizumab and corticosteroids. As CAR-T cell therapy expands to new disease indications and the number of long-term survivors steadily increases, there is growing recognition of the need to appropriately evaluate and manage the late effects of CAR-T cell therapy, including late-onset or persistent neurotoxicity, prolonged cytopenias, delayed immune reconstitution and infections, subsequent malignancies, organ dysfunction, psychological distress, and fertility implications. In this review, we provide a practical approach to the long-term survivorship care of the CAR-T cell recipient, with a focus on the optimal strategies to address the common and challenging late complications affecting this unique population.

Thresholds for Red Blood Cell Transfusion in Preterm Infants: Evidence to Practice

Rapid blood loss with circulatory shock is dangerous for the preterm infant as cardiac output and oxygen-carrying capacity are simultaneously imperilled. This requires prompt restoration of circulating blood volume with emergency transfusion. It is recommended that clinicians use both clinical and laboratory responses to guide transfusion requirements in this situation. For preterm infants with anemia of prematurity, it is recommended that clinicians use a restrictive algorithm from one of two recently published clinical trials. Transfusion outside these algorithms in very preterm infants is not evidence-based and is actively discouraged.

SHOT UK Collaborative Reviewing and Reforming IT Processes in Transfusion (SCRIPT) survey: Laboratory information management systems: Are we ready for digital transformation?

OBJECTIVES

To understand the use, functionality and interoperability of laboratory information management systems (LIMS) in UK transfusion laboratories.

BACKGROUND

LIMS are widely used to support safe transfusion practice. LIMS have the potential to reduce the risk of laboratory error using algorithms, flags and alerts that support compliance with best practice guidelines and regulatory standards. Reporting to Serious Hazards of Transfusion (SHOT), the United Kingdom (UK) haemovigilance scheme, has identified cases where the LIMS could have prevented errors but did not. Shared care of patients across different organisations and the development of pathology networks has raised challenges relating to interoperability of IT systems both within, and between, organisations.

METHODS AND MATERIALS

A survey was distributed to all SHOT-reporting organisations to understand the current state of LIMS in the UK, prevalence of expertise in transfusion IT, and barriers to progress. Survey questions covered LIMS interoperability with other IT systems used in the healthcare setting.

RESULTS

A variety of LIMS and version numbers are in use in transfusion laboratories, LIMS are not always updated due to resource constraints. Respondents identified interoperability and improved functionality as the main requirements for transfusion safety.

CONCLUSION

A nationally agreed set of minimum standards for transfusion LIMS is required for safe practice. Adequate resources, training and expertise should be provided to support the effective use and timely updates of LIMS. A single LIMS solution should be in place for transfusion laboratories working within a network and interoperability with other systems should be explored to further improve practice.

How do we perform intrauterine transfusions?

BACKGROUND

Intrauterine transfusion (IUT) is an invasive but critical and potentially life-saving intervention for severe fetal anemia with demonstrated improvement in outcomes. The fetus is vulnerable to hemodynamic alterations and transfusion-related adverse events; therefore, special consideration must be given to blood component selection and modification. There is widespread IUT practice variability, and existing guidance primarily relies on expert opinion and single center experiences.

STUDY DESIGN AND METHODS

Experts in Maternal Fetal Medicine, Pediatric Hematology, and Transfusion Medicine from centers across the United States, collectively performing about 120 IUT annually, offer a multidisciplinary perspective on the performance of IUT and preparation of blood components. This perspective includes strategies for identifying an at-risk fetus, communicating between disciplines, determining the necessary blood volume, selecting and processing blood components, documenting the procedure in medical record, and managing the neonate.

RESULTS

Identifying an at-risk fetus relies on review of the clinical history, non-invasive monitoring, and laboratory evaluation. We recommend the use of relatively fresh, group O, cytomegalovirus-safe, freshly irradiated, red blood cells (RBC) that are Hemoglobin S negative and antigen-negative for any maternal antibody, if indicated. These RBC units should be concentrated to remove additives and increase the hematocrit thus minimizing fluctuations in fetal volume status. The units intended for IUT should be labeled clearly and the documentation of transfusion differentiated in the maternal medical record.

DISCUSSION

An awareness of the technical, logistical, and regulatory considerations for IUT performance will facilitate improved communication and patient care, especially when rare units of RBC are required.

Neonatal Blood Banking Practices

There is little formal guidance to direct neonatal blood banking practices and, as a result, practices vary widely across institutions. In this vulnerable patient population with a high transfusion burden, considerations for blood product selection include freshness, extended-storage media, pathogen inactivation, and other modifications. The authors discuss the potential unintended adverse impacts in the neonatal recipient. Concerns such as immunodeficiency, donor exposures, cytomegalovirus transmission, volume overload, transfusion-associated hyperkalemia, and passive hemolysis from ABO incompatibility have driven modifications of blood components to improve safety.

Immune effector cell-associated hematotoxicity: EHA/EBMT consensus grading and best practice recommendations

Hematological toxicity is the most common adverse event after chimeric antigen receptor (CAR) T-cell therapy. Cytopenias can be profound and long-lasting and can predispose for severe infectious complications. In a recent worldwide survey, we demonstrated that there remains considerable heterogeneity in regard to current practice patterns. Here, we sought to build consensus on the grading and management of immune effector cell-associated hematotoxicity (ICAHT) after CAR T-cell therapy. For this purpose, a joint effort between the European Society for Blood and Marrow Transplantation (EBMT) and the European Hematology Association (EHA) involved an international panel of 36 CAR T-cell experts who met in a series of virtual conferences, culminating in a 2-day meeting in Lille, France. On the basis of these deliberations, best practice recommendations were developed. For the grading of ICAHT, a classification system based on depth and duration of neutropenia was developed for early (day 0-30) and late (after day +30) cytopenia. Detailed recommendations on risk factors, available preinfusion scoring systems (eg, CAR-HEMATOTOX score), and diagnostic workup are provided. A further section focuses on identifying hemophagocytosis in the context of severe hematotoxicity. Finally, we review current evidence and provide consensus recommendations for the management of ICAHT, including growth factor support, anti-infectious prophylaxis, transfusions, autologous hematopoietic stem cell boost, and allogeneic hematopoietic cell transplantation. In conclusion, we propose ICAHT as a novel toxicity category after immune effector cell therapy, provide a framework for its grading, review literature on risk factors, and outline expert recommendations for the diagnostic workup and short- and long-term management.

Transfusion-Associated Graft-Versus-Host Disease in Adults

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare but fatal complication of blood transfusion that usually develops two to 30 days following a blood transfusion giving rise to graft versus host disease (GVHD) clinical features that are consisting of fever, skin rash, jaundice, diarrhea, and pancytopenia. The disease is fulminant in most patients with a mortality rate of >90% of cases. The main aim of this review is to enhance awareness among medical practitioners about this fatal disease. Data were extracted manually from the main medical databases (Medline, Scopus, and Google Scholar) after the revision of selected articles and assessed for their contribution to the knowledge of TA-GVHD. TA-GVHD occurs when the viable donor T-cells in the blood or blood products attack the recipient's tissues which his/her immune system is incapable to destroy due to several reasons. The recipient's tissues that are usually involved in TA-GVHD include the liver, intestine, skin, lungs, and bone marrow. Any blood component either whole blood, packed red blood cells (RBCs), platelets, or fresh non-frozen plasma that contains viable T lymphocytes can cause TA-GVHD. Host immunodeficiency, transfusion of fresh blood, and partial human leukocyte antigen (HLA) matching between the donors and the recipients represent the major risk factors of TA-GVHD. Partial HLA matching includes immunocompetent recipients who receive blood from a first-degree relative also, seen in genetically homogenous populations because of high rates of consanguineous marriage. The diagnosis of TA-GVHD is mainly suspected based on clinical manifestations. However, a histopathological study of either skin or rectal biopsy is diagnostic. The treatment of TA-GVHD is generally not effective, unless the patient received emergency stem cell transplantation, while prevention via irradiation of blood or blood products represents the standard of care for this disease. In conclusion, medical practitioners should have a high index of suspicion for this disease. Moreover, future clinical trials targeting and comparing the outcomes of the different therapeutic options for TA-GVHD are required.

Idiopathic Aplastic anemia: Indian Perspective

Aplastic anemia (AA) is a rare immunologically mediated bone marrow failure syndrome, characterized by progressive loss of hematopoietic stem cells resulting in peripheral pancytopenia. Elaborative investigation including molecular tests is required to exclude inherited bone marrow failure syndrome (IMBFS) as the treatment and prognosis vary dramatically between them. Haematopoietic stem cell transplant with a fully matched sibling donor (MSD-HSCT) is still the only curative treatment. Management of AA is a real-time challenge in India, because of the delay in the diagnosis, lack of proper supportive care, limited availability of the expertise centre, and the patient's affordability. Recently, results with intensified immunosuppressive therapy that includes anti-thymocyte globulin with cyclosporine-A (CsA) and eltrombopag, are enough encouraging to consider it as treatment of choice in patients lacking MSD or who are not fit for HSCT. However, limitations in resource constraints settings including the cost of therapy limit its full utilization. Relapse of the disease or evolution to myelodysplasia or paroxysmal nocturnal haemoglobinuria (PNH) in a proportion of patients is another challenge with immunosuppressants. The majority of the AA patients still receive CsA with or without androgens in India, mostly because of increased cost and limited availability of HSCT and ATG. The use of the unrelated or alternative donor is still upcoming in India, with unavailable data in terms of response and survival. Therefore, there is an utmost need for novel agents for the better management of AA having a balanced efficacy and toxicity profile to improve the survival and quality of life.

Battle of the (Chat)Bots: Comparing Large Language Models to Practice Guidelines for Transfusion-Associated Graft-Versus-Host Disease Prevention

Published guidelines and clinical practices vary when defining indications for irradiation of blood components for the prevention of transfusion-associated graft-versus-host disease (TA-GVHD). This study assessed irradiation indication lists generated by multiple artificial intelligence (AI) programs, or chatbots, and compared them to 2020 British Society for Haematology (BSH) practice guidelines. Four chatbots (ChatGPT-3.5, ChatGPT-4, Bard, and Bing Chat) were prompted to list the indications for irradiation to prevent TA-GVHD. Responses were graded for concordance with BSH guidelines. Chatbot response length, discrepancies, and omissions were noted. Chatbot responses differed, but all were relevant, short in length, generally more concordant than discordant with BSH guidelines, and roughly complete. They lacked several indications listed in BSH guidelines and notably differed in their irradiation eligibility criteria for fetuses and neonates. The chatbots variably listed erroneous indications for TA-GVHD prevention, such as patients receiving blood from a donor who is of a different race or ethnicity. This study demonstrates the potential use of generative AI for transfusion medicine and hematology topics but underscores the risk of chatbot medical misinformation. Further study of risk factors for TA-GVHD, as well as the applications of chatbots in transfusion medicine and hematology, is warranted.

Human leukocyte antigen alloimmunization prevention mechanisms in blood transfusion

In many fields of clinical medicine and blood transfusion, the human leukocyte antigen (HLA) system is crucial. Alloimmunization happens as a result of an immune response to foreign antigens encountered during blood transfusion. This gives rise to alloantibodies against red blood cells (RBCs), HLA, or human platelet antigen (HPA). HLA alloimmunization following allogeneic transfusion was shown to be a result of contaminating white blood cells (WBCs) present in the product. It is a common complication of transfusion therapy that leads to difficulties in clinical intolerance and refractoriness to platelet transfusion during patient management. Single-donor platelets, prophylactic HLA matching, leukoreduction, and irradiation of cellular blood products are some of the mechanisms to prevent HLA alloimmunization during a blood transfusion. Now, the best approach to reduce the occurrence of primary HLA alloimmunization is the removal of WBCs from the blood by filtration.

Transfusion support in hematopoietic stem cell transplantation

Transfusion support for hematopoietic stem cell transplantation (HSCT) is an essential part of supportive care, and compatible blood should be transfused into recipients. As leukocyte antigen (HLA) matching is considered first and as the blood group does not impede HSCT, major, minor, bidirectional, and RhD incompatibilities occur that might hinder transfusion and cause adverse events. Leukocyte reduction in blood products is frequently used, and irradiation should be performed for blood products, except for plasma. To mitigate incompatibility and adverse events, local transfusion guidelines, hospital transfusion committees, and patient management should be considered.

How do I provide rare red cells to patients?

BACKGROUND

The demand for rare blood is expected to increase in Canada as its population continues to expand through immigration from diverse regions of the world.

MATERIAL AND METHODS

This paper outlines a national approach to providing rare red cells for patients through the Rare Blood Program of Canadian Blood Services (CBS). Data detailing the rare red cell requests and inventory managed by CBS' Rare Blood Program is provided.

RESULTS

The provision of rare red cells involves multiple considerations such as multidisciplinary communication, serologic/molecular confirmation, donor recruitment, inventory optimization and logistical factors.

CONCLUSION

The description of CBS' Rare Blood Program will inform others that seek to create, optimize, or expand programs that facilitate the provision of rare blood. New technologies such as next-generation sequencing may also affect how rare donors are identified and recruited in the future.

Demographics and appropriateness of cellular blood component irradiation practices: Ambispective analysis from a tertiary care center

BACKGROUND

Transfusion-associated graft versus host disease (TA-GVHD) is often underreported. There may also be lapses in TA-GVHD prevention practices due to lack of revision of some of the existing clinical guidelines as well as limited audits on practices of blood component irradiation. This study was undertaken to highlight these shortcomings, and generate data for development of institutional guidelines.

METHODS/MATERIALS

Study cohort was selected from patients requiring transfusion support during June 2019 to May 2020. Transfusion history of these patients were followed, both retrospectively and prospectively till July 2021. Transfusion requisitions were categorized as IR (with request for irradiation) or NIR (with no request for irradiation) and justified or unjustified according to published international guidelines.

RESULTS

Total 6963 requisitions for cellular blood components were received from 255 patients included in the study cohort. Of these, 3690 (54.9 %) were IR requisitions, while remaining 3029 (45.1 %) requisitions were NIR. Overall, 4242 (63.1 %) requisition were justified for their irradiation status as per published guidelines and 1595 (23.8 %) were found to be Unjustified while justification could not be assessed for remaining 882 (13.1 %) of the requisitions. The highest proportion of Unjustified demands in NIR requisitions was observed in patients with Severe Aplastic anemia (59.4 %).

CONCLUSION

Many units were unnecessarily irradiated (7.7 %) while irradiation was missed in 16 % of the requisitions included in analysis which may be attributed to lack of institutional guidelines. We recommend that every centre should adopt a published well-researched guideline including amendments based on review of practices at their center.

Clinical Practice Guidelines for the Immunological Management of Chromosome 22q11.2 Deletion Syndrome and Other Defects in Thymic Development

Current practices vary widely regarding the immunological work-up and management of patients affected with defects in thymic development (DTD), which include chromosome 22q11.2 microdeletion syndrome (22q11.2del) and other causes of DiGeorge syndrome (DGS) and coloboma, heart defect, atresia choanae, retardation of growth and development, genital hypoplasia, ear anomalies/deafness (CHARGE) syndrome. Practice variations affect the initial and subsequent assessment of immune function, the terminology used to describe the condition and immune status, the accepted criteria for recommending live vaccines, and how often follow-up is needed based on the degree of immune compromise. The lack of consensus and widely varying practices highlight the need to establish updated immunological clinical practice guidelines. These guideline recommendations provide a comprehensive review for immunologists and other clinicians who manage immune aspects of this group of disorders.

Incompatible red blood cell transfusion for hemolytic disease of the fetus and newborn secondary to anti-U: A case report

BACKGROUND

Hemolytic disease of the fetus and newborn (HDFN) is a challenging condition that may necessitate the need for intrauterine or neonatal transfusion. The ability to provide compatible blood depends on antibody identification and antigen prevalence. We describe the case of a newborn that was affected by HDFN secondary to a high-prevalence antigen of unknown specificity.

STUDY DESIGN AND METHODS

A 29-year-old mother underwent emergency cesarean section for fetal distress. The newborn had severe anemia and hyperbilirubinemia. Antibody screening and identification on maternal plasma revealed pan reactivity with negative autocontrol. The cord sample had the same pattern with positive Direct Antiglobulin Test. Incompatible group O red blood cells were transfused to the newborn with no complications.

RESULTS

Testing the maternal sample at a reference laboratory revealed the presence of anti-U at a high titer.

DISCUSSION

In life-threatening conditions, it may be necessary to transfuse incompatible units. In patients who require transfusion in the presence of an identified antibody against a high-prevalence antigen, sources for rare blood should be explored. These include autologous donations for adults, collecting blood from relatives (including mothers), and fresh or frozen units from rare donors through rare donor registries.

[Obtaining blood components in blood banks]

After the first successful blood transfusion, different difficulties of a liquid tissue were overcome; this liquid required special conditions to keep its characteristics with minimal alterations and, thus, to be able to be used in patients who needed it. Subsequently, techniques that also made possible to separate this liquid into its different components for its use were discovered, allowing a more specific treatment of the deficiencies of patients when administering cellular or non-cellular elements. With this, a new area arose within the blood banks to obtaining components. This area became the central point of convergence of all the processes involved in obtaining components, which include the biological qualification of each one of the units, as well as their labeling and release for the different distribution in transfusion services. It is important to highlight that the main source of components is obtained from whole blood; its processing for several decades was an artisanal operator-dependent process; however, with the evolution of technology, now it is possible to carry it out in an automated manner; likewise, today it is possible to obtain components directly from the donor's whole blood by separating it in real time by means of apheresis, which allows obtaining the component of interest and returning the remainder to the donor.

Hand-Made Polytetrafluoroethylene Tricuspid-Valved Conduit for Surgical Reconstruction of the Right Ventricular Outflow Tract in a Child With Truncus Arteriosus

Although a new right ventricle outflow can be introduced during pulmonary artery reconstruction, it is a suboptimal option as the valved conduits that mimic the natural right ventricular outflow do not grow, and a surgical conduit replacement cannot be averted. This study reported the implementation of hand-made polytetrafluoroethylene (PTFE) tricuspid-valved conduits to rebuild the right ventricular outflow tract in toddlers with truncus arteriosus and risk factors for earlier conduit explant. Herein, we described a case report of a 9-month-old toddler diagnosed in November 2021 with truncus arteriosus type I with ventricular septal defect (VSD) and severe pulmonary arterial hypertension, who has been successfully discharged 20-days postoperative surgical reconstruction with good bi-ventricular functions. Hand-made PTFE tricuspid-valved conduits are efficient in the reconstruction process of the right ventricular outflow tract in children with truncus arteriosus. The conduits are cheap, easily available, and lack potential sensitization.

Bendamustine treatment of haematological malignancies: significant risks of opportunistic viral, fungal and bacterial infections

OBJECTIVES

Bendamustine is a standard treatment for low-grade B-cell lymphomas, and considered safe in clinical trials. Its safety in routine practice might be different.

METHODS

We retrospectively analyzed the infection complications in an unselected cohort of patients treated with bendamustine over a nine-year period. Patients were regularly monitored for blood counts and cytomegalovirus (CMV) reactivation by antigen assay and polymerase chain reaction. They received granulocyte colony stimulating factor for neutropenia, and routine anti-pneumocystis and optional anti-fungal prophylaxis.

RESULTS

There were 179 men and 127 women at a median age of 61.5 (20-90) years, 52% receiving bendamustine for relapsed/refractory disease. Malignancies included low-grade B-cell lymphomas (54%), myeloma (10%), T-cell lymphomas (11%), Hodgkin lymphoma (2%) and other lymphoid neoplasms (23%). Most patients had good performance status (Eastern Cooperative Oncology Group score: 0-1, 72%). CMV reactivation occurred in 58 patients (19%) at a median age of 68 (39-85) years. Univariate analysis showed CMV reactivation to be significantly associated with elevated lactate dehydrogenase (P = 0.045), decreased albumin (P = 0.003) and older age (reactivation versus no reactivation: 66.3 ± 11.4 versus 59.4 ± 14.5 years, P = 0.0016). Age remained the only significant risk on multivariate analysis. CMV reactivation resulted in retinitis (N = 4), ependymitis/ventriculitis (N = 1) and duodenitis/colitis (N = 1). Invasive fungal disease occurred in five patients (candidemia, N = 2; aspergillosis N = 1; cryptococcemia, N = 1; scedosporiosis, N-1). Nineteen patients had culture positive septicaemia.

CONCLUSION

Our observations showed that even with a vigorous anti-infective strategy, bendamustine treatment was still associated with significant risks of bacterial and opportunistic viral and fungal infections.

Immune responses against SARS-CoV-2 variants after two and three doses of vaccine in B-cell malignancies: UK PROSECO study

Patients with hematological malignancies are at increased risk of severe COVID-19 outcomes due to compromised immune responses, but the insights of these studies have been compromised due to intrinsic limitations in study design. Here we present the PROSECO prospective observational study ( NCT04858568 ) on 457 patients with lymphoma that received two or three COVID-19 vaccine doses. We show undetectable humoral responses following two vaccine doses in 52% of patients undergoing active anticancer treatment. Moreover, 60% of patients on anti-CD20 therapy had undetectable antibodies following full vaccination within 12 months of receiving their anticancer therapy. However, 70% of individuals with indolent B-cell lymphoma displayed improved antibody responses following booster vaccination. Notably, 63% of all patients displayed antigen-specific T-cell responses, which increased after a third dose irrespective of their cancer treatment status. Our results emphasize the urgency of careful monitoring of COVID-19-specific immune responses to guide vaccination schemes in these vulnerable populations.

Guideline for the first-line management of Classical Hodgkin Lymphoma - A British Society for Haematology guideline

This guideline was compiled according to the British Society for Haematology (BSH) process at https://b-s-h.org.uk/media/16732/bsh-guidance-development-process-dec-5-18.pdf. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluate levels of evidence and to assess the strength of recommendations. The GRADE criteria can be found at http://www.gradeworkinggroup.org. Recommendations are based on a review of the literature using Medline, PubMed/Medline and Cochrane searches beginning from 2013 up to January 2021. The following search terms were used: [Hodgkin lymphoma OR Hodgkin disease] NOT non-Hodgkin; AND [chemotherapy OR radiotherapy]; AND [elderly]; AND [teenage OR adolescent OR young adult]; AND [pregnancy]. Filters were applied to include only publications written in English, studies carried out in humans, clinical conferences, congresses, clinical trials, clinical studies, meta-analyses, multicentre studies and randomised controlled trials. References pre-2013 were taken from the previous version of this guideline.¹ Review of the manuscript was performed by the British Society for Haematology (BSH) Guidelines Committee Haematology Oncology Taskforce, the BSH Guidelines Committee and the Haematology Oncology sounding board of BSH.

Irradiation of platelets in Transfusion Medicine: risk and benefit judgments

Irradiation of platelet products is generally used to prevent transfusion-associated graft-versus-host disease (TA-GvHD) as well as transfusion-transmitted infections. As an essential prerequisite, gamma-irradiation of blood products prior to transfusion is required in patients who may develop TA-GVHD. Most studies suggest that gamma irradiation has no significant effect on the quality of platelet products; however, more recent studies have shown that the oxidative effects of gamma irradiation can lead to the induction of platelet storage lesion (PSL) and to some extent reduce the efficiency of transfused platelets. As the second widely used irradiation technique, UV-illumination was primarily introduced to reduce the growth of infectious agents during platelet storage, with the advantage that this method can also prevent TA-GvHD. However, the induction of oxidative conditions and platelet pre-activation that lead to PSL is more pronounced after UV-based methods of pathogen reduction. Since these lesions are large enough to clearly affect the post-transfusion platelet recovery and survival, more studies are needed to improve the safety and effectiveness of pathogen reduction technologies (PRTs). Therefore, pointing to other benefits of PRTs, such as preventing TA-GvHD or prolonging the shelf life of products by eliminating the possibility of pathogen growth during storage, does not yet seem to justify their widespread use due to above-mentioned effects. Even for gamma-irradiated platelets, some researchers have suggested that due to decreased 1-hour post-transfusion increments and increased risk of platelet refractoriness, their use should be limited to the patients who may develop TA-GVHD. It is noteworthy that due to the effect of X-rays in preventing TA-GvHD, some recent studies are underway to examine its effects on the quality and effectiveness of platelet products and determine whether X-rays can be used as a more appropriate and cost-effective alternative to gamma radiation. The review presented here provides a detailed description about irradiation-based technologies for platelet products, including their applications, mechanistic features, advantages, and disadvantages.

X-irradiation and gamma-irradiation inactivate lymphocytes in blood components

BACKGROUND

Irradiation of selected blood components is standard practice for the prevention of transfusion-associated graft-versus-host disease (TA-GvHD). Currently, gamma-irradiation is the most widely used form of irradiation, but there is an increasing interest in X-irradiation, which is considered to be functionally equivalent and safer. However, there is a paucity of contemporary data regarding the ability of X-irradiation to inactivate lymphocytes in blood components. Therefore, the effect of gamma- and X-irradiation on lymphocyte viability and function in blood components was compared.

STUDY DESIGN AND METHODS

Lymphocytes were isolated from venous blood by density gradient centrifugation, spiked into plasma/SSP+ to simulate a blood component, and either gamma- or X-irradiated. The phenotype of the isolated lymphocytes was confirmed. Lymphocyte viability was measured using a LIVE/DEAD assay, and function was assessed using mixed lymphocyte culture and CD69 expression post-phorbol-12 myristate 13-acetate (PMA) stimulation.

RESULTS

Lymphocyte viability and CD69 expression following PMA stimulation were significantly reduced by both gamma-irradiation and X-irradiation in simulated blood components. Allorecognition and allostimulation were also significantly reduced by both gamma-irradiation and X-irradiation.

CONCLUSION

Lymphocyte viability and function are reduced to a similar extent by gamma- and X-irradiation in simulated blood components. As such, X-irradiation is suitable for the irradiation of blood components and, in terms of lymphocyte inactivation, could be used instead of gamma-irradiation.

X- and gamma-irradiation have similar effects on the in vitro quality of stored red cell components

BACKGROUND

Blood components are irradiated to inactivate lymphocytes to prevent transfusion-associated graft versus host disease. As there are little data regarding the effects of X-irradiation on red blood cell components (RBCs), the in vitro quality of stored red cells (standard, pediatric, washed, and intra-uterine transfusion [IUT]) following X- or gamma-irradiation was compared.

STUDY DESIGN AND METHODS

RBCs were pooled, split, and processed to produce standard (<14 days and < 5 days post-collection), pediatric (<5 days post-collection), washed (<14 days post-collection), or IUT RBCs (<5 days post-collection). Standard RBCs were either X- or gamma-irradiated (n = 10 pairs). A further 10 replicates were prepared by pooling and splitting three matched RBCs (X-, gamma-, and non-irradiated). All other RBCs were either X- or gamma-irradiated (n = 20 pairs). Red cell indices, hemolysis, potassium release, metabolism, microparticles, ATP, and 2,3-DPG were measured pre-irradiation and 6 h, 1, 2, 3, 7, 10, and 14 days post-irradiation, depending on the component type. Data were analyzed using two-way repeated measures ANOVA.

RESULTS

There were no significant differences in any in vitro quality measurements, with the exception of marginally higher potassium release in washed, IUT, and RBCs <5 days old (p < .0001) following X-irradiation. Both irradiation types increased generation of microvesicles, particularly in components that were older at the time of irradiation or stored for longer post-irradiation.

CONCLUSION

X- and gamma-irradiation have similar effects on the in vitro quality of RBCs, indicating that either technology is suitable for blood component irradiation.

Guideline development for prevention of transfusion-associated graft-versus-host disease: reduction of indications for irradiated blood components after prestorage leukodepletion of blood components

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare, commonly fatal complication of transfusion preventable by irradiation of blood units. The revision of the Dutch transfusion guideline addressed the question whether irradiation is still necessary if blood components are prestorage leukodepleted. We searched for published cases of TA-GVHD following transfusion of prestorage leukodepleted blood and through contacting haemovigilance systems. Six presumed cases were found, dating from 1998 to 2013. Four out of six patients had received one or more non-irradiated units despite recognised indications for irradiated blood components. In the countries providing information, over 50 million prestorage leukodepleted, non-irradiated, non-pathogen-reduced cellular components were transfused in a 10-year period. Potential benefits of lifting indications for irradiation were considered. These include reduced irradiation costs (€ 1.5 million annually in the Netherlands) and less donor exposure for neonates. Findings were presented in an invitational expert meeting. Recommendations linked to human leukocyte antigen similarity between donor and recipient or intra-uterine transfusion were left unchanged. Indications linked to long-lasting deep T-cell suppression were defined with durations of 6 or 12 months after end of treatment (e.g. autologous or allogeneic stem cell transplantation). Need for continued alertness to TA-GVHD and haemovigilance reporting of erroneous non-irradiated transfusions was emphasised.

DEHT is a suitable plasticizer option for phthalate-free storage of irradiated red blood cells

BACKGROUND AND OBJECTIVES

Due to increasing concerns about possible endocrine-disrupting properties, the use of the plasticizer di(2-ethylhexyl) phthalate (DEHP) will be banned in future blood storage. Di(2-ethylhexyl) terephthalate (DEHT) provides sufficient red blood cell (RBC) quality during conventional blood bank storage. It is important that a new plasticizer also maintains acceptable quality during exposure to high cell stress, such as irradiation, which is commonly used to prevent graft-versus-host disease.

MATERIALS AND METHODS

A total of 59 RBC units were collected and processed in polyvinyl chloride (PVC)-DEHT or PVC-DEHP blood bags combined with either saline-adenine-glucose-mannitol (SAGM) or phosphate-adenine-glucose-guanosine-saline-mannitol (PAGGSM) additive solution. All units were X-ray irradiated on day 2 post-collection. Sampling for assessment of parameters of storage lesion was performed on day 2 pre-irradiation and day 14 and 28 post-irradiation.

RESULTS

Though irradiation increased cell stress, DEHT/PAGGSM and current common European preference DEHP/SAGM were equally affected up to 14 days post-irradiation for all measured parameters. At day 28, haemolysis and microvesicle count were slightly increased in DEHT, whereas extracellular potassium ions, glucose, lactate, pH, mean corpuscular volume and microvesicle phosphatidylserine remained unaffected by plasticizer choice throughout storage. No individual unit exceeded 0.8% haemolysis, not even in DEHT/SAGM, the combination overall most affected by irradiation. Of the four combinations, membrane stability was least impacted in DEHP/PAGGSM.

CONCLUSION

We demonstrate that DEHT is a suitable plasticizer for storage of RBCs after X-ray irradiation cell stress. This strengthens the option of DEHT as a viable non-phthalate substitute for DEHP.

A comparison of the effect of X and gamma irradiation on red cell storage quality

BACKGROUND AND OBJECTIVES

Irradiation of red cell components is indicated for recipients at risk of transfusion-associated graft vs. host disease. Current technologies available comprise of a gamma (γ) or an x source of radiation. The benefits of x vs. γ include non-radioactivity and hence no decay of the source. We aimed to compare the effect of the two technologies on red cell component storage quality post-irradiation.

MATERIALS AND METHODS

Paired units of red cell concentrates (RCC), neonatal red cell splits (RCS), red cells for intra-uterine transfusion (IUT) or neonatal exchange transfusion (ExTx) were either γ- or x-irradiated. Units were sampled and tested for five storage parameters until the end of shelf life. Equivalence analysis of storage quality parameters was performed for pairs of the same components (RCC, RCS, IUT or ExTx) that were either γ- or x-irradiated.

RESULTS

Nearly all component comparisons studied showed equivalence between γ and x irradiation for haemolysis, ATP, 2,3-DPG, potassium release and lactate production. The exceptions found that were deemed non-equivalent were higher haemolysis with x irradiation for ExTx, lower 2,3-DPG with x irradiation for RCS irradiated early and higher ATP with x irradiation for IUT. However, these differences were considered not clinically significant.

CONCLUSION

This study has demonstrated that a range of red cell components for use in different age groups are of acceptable quality following x irradiation, with only small differences deemed clinically insignificant in a few of the measured parameters.

Bestrahlung zellulärer Blutprodukte – Änderungen in den neuen Querschnitts-Leitlinien

Die transfusionsassoziierte Graft-versus-Host-Erkrankung (ta-GvHD) ist eine seltene, aber lebensbedrohliche Nebenwirkung der Transfusion zellulärer Blutprodukte, die durch restliche Lymphozyten des Blutspenders hervorgerufen wird. Risikofaktoren für eine ta-GvHD sind eine geschwächte T-zelluläre Abwehr des Patienten, eine hohe Zahl residueller Lymphozyten im Blutprodukt und eine einseitige HLA-Inkompatibilität zwischen Spender und Empfänger. Durch eine Bestrahlung zellulärer Blutkomponenten mit mindestens 25 Gray lässt sich eine ta-GvHD sicher verhindern. In der gerade erschienenen 5. Auflage der Querschnitts-Leitlinien der Bundesärztekammer zur Therapie mit Blutkomponenten und Plasmaderivaten wurden einige Indikationen zur Bestrahlung gelockert, da Erfahrungen aus Großbritannien zeigen, dass hier auch nach Transfusion unbestrahlter Blutprodukte kein Risiko für eine ta-GvHD besteht. So stellen lymphatische Neoplasien nicht mehr generell eine Bestrahlungsindikation dar, sondern nur, wenn ein Hodgkin-Lymphom oder ein schwerer T-Zell-Defekt vorliegt oder wenn bestimmte Therapien durchgeführt werden bzw. wurden (z. B. Gabe von Purinanaloga). Zu anderen Indikationen finden sich in den revidierten Querschnitts-Leitlinien erstmals Empfehlungen zur Verwendung bestrahlter Blutkomponenten: Dies betrifft z. B. hämatoonkologische Patienten unter Therapie mit ATG oder Alemtuzumab. Der Artikel fasst den aktuellen Erkenntnisstand zur ta-GvHD kurz zusammen und erläutert die Änderungen der revidierten Querschnitts-Leitlinien.

A high transfusion burden following an ambulatory-allogeneic hematopoietic cell transplantation using reduced-intensity conditioning is associated with adverse outcomes

OBJECTIVES

Ambulatory allogeneic hematopoietic cell transplantation (allo-HCT) after reduced-intensity conditioning (RIC) is a cost-effective option for hematology patients. Data on the impact of transfusion burden in this setting are scarce; we analyzed this retrospectively.

METHODS

A study of 177 HLA-identical and haploidentical allo-HCT recipients on an outpatient basis was conducted between 2013 and 2019. Packed red blood cell (PRBC) and platelet transfusions were documented from days 0-100 after HCT.

RESULTS

A total of 121 patients (68.4%) required transfusion while 56 (31.6%) did not. In the multivariate analysis, a lower disease-free (DFS) and overall survival (OS) were documented for patients that received ≥9 total blood products (p = 0.018) (p = 0.014), those who required hospitalization (p = 0.001) (p < 0.001), had acute graft-versus-host disease (p = 0.016) (p = 0.004), and a high/very high Disease-Risk-Index (p = 0.002; p = 0.004), respectively. Transfusion of ≥5 PRBC units was associated with a lower OS (p = 0.027). The cumulative incidence of transplant-related mortality at two years for an HLA-identical transplant was 9.5% and for haploidentical, it was 27.1% (p = 0.027); this last group had significantly more transfusion demands than HLA-identical recipients (p = 0.029).

CONCLUSION

Increased blood product utilization is an independent predictor of decreased survival in ambulatory RIC allo-HCT recipients. Further evidence leading to individualized guidelines to transfuse in this complex scenario is needed.

Missed irradiation of cellular blood components for vulnerable patients: Insights from 10 years of SHOT data

Background

Irradiation of cellular blood components is recommended for patients at risk of transfusion‐associated graft‐vs‐host disease (TA‐GvHD). Prestorage leucodepletion (LD) of blood components is standard in the UK since 1999.

Study Design and Methods

Analysis of 10 years' reports from UK national hemovigilance scheme, Serious Hazards of Transfusion (2010‐2019), where patients failed to receive irradiated components when indicated according to British Society for Haematology guidelines (2011).

Results

There were 956 incidents of failure to receive irradiated components all due to errors. One hundred and seventy two incidents were excluded from analysis, 125 of 172 (72.7%) because of missing essential information. No cases of TA‐GvHD were reported in this cohort. The 784 patients received 2809 components (number unknown for 67 incidents). Most failures occurred in patients treated with purine analogues (365) or alemtuzumab (69), or with a history of Hodgkin lymphoma (HL) (192). Together these make up 626 of 784 (79.9%). Poor communication is an important cause of errors.

Conclusion

Leucodepletion appears to reduce the risk for TA‐GvHD. None of 12 cases of TA‐GvHD reported to SHOT prior to introduction of LD occurred in patients with conditions recommended for irradiated components by current guidelines. Irradiation indefinitely for all stages of HL is not based on good evidence and is a difficult guideline to follow. Further research on long‐term immune function in HL is required. Variation between different national guidelines reflects the very limited evidence.