Incompatible Blood Transfusion Research Articles

Investigation of the Frequency of Reactions and Consequences of Blood Transfusion in an Academic Center Guilan-Iran

Background: Blood transfusion is a life-saving procedure, but there are always potential risks, such as blood transfusion reactions. Objectives: Considering the importance of the subject and the lack of a similar study in Guilan province, this research was conducted to analyze blood transfusion reactions. Methods: This retrospective descriptive study was conducted at Al-Zahra Hospital in Guilan, Iran, between 2020 and 2022. The files of all patients who received blood products at this center and experienced a reaction were reviewed. A checklist was completed, which included details such as the hospital ward, age, blood group, underlying disease, type of surgery, type of injected product, history of transfusion, history of reaction and allergy, type of reaction, and treatment intervention. Results: During the study period, 4,887 cases received transfusions. Among them, 18 cases (0.36%) showed reactions during transfusion, of which 14 cases (0.35% of total packed cell injections) were related to packed cell injection. Shivering was the most common reaction, occurring in 8 cases (15.38%). The main interventions included the administration of steroids in 10 cases (25%), antihistamines in 7 cases (17.5%), and oxygen therapy in 7 cases (17.5%). Three cases (7.5%) were transferred to the ICU, and in three cases (7.5%), the blood transfusion was stopped. One mortality was reported, and no cases of incompatible blood transfusion were documented. Conclusions: The incidence of reactions to blood product injections at this center appears to be acceptable. However, it was found that the information recording systems were very inefficient, and forms were incompletely filled, which should be addressed and corrected.

Simultaneous high throughput genotyping of 36 blood group systems using NGS based on probe capture technology

Human blood group antigen has important biological functions, and transfusion of incompatible blood can cause alloimmunization and may lead to serious hemolytic reactions. Currently, serological methods are most commonly used in blood group typing. However, this technique has certain limitations and cannot fully meet the increasing demand for the identification of blood group antigens. This study describes a next-generation sequencing (NGS) technology platform based on exon and flanking region capture probes to detect full coding exon and flanking intron regions of the 36 blood group systems, providing a new high-throughput method for the identification of blood group antigens. The 871 capture probes were designed for the exon and flanking intron sequences of 36 blood group system genes, and synchronization analysis for 36 blood groups was developed. The library for NGS was tested using the MiSeq Sequencing Reagent Kit (v2, 300 cycles) by Illumina NovaSeq, and the data were analyzed by the CLC Genomics Workbench 21.0 software. A total of 199 blood specimens have been sequenced for the 41 genes from 36 blood groups. Among them, heterozygote genotypes were found in the ABO, Rh, MNS, Lewis, Duffy, Kidd, Diego, Gerbich, Dombrock, Globoside, JR, LAN, and Landsteiner-Wiene blood group systems. Only the homozygous genotype was found in the remaining 22 blood group systems. The obtained data in the NGS method shows a good correlation (99.98 %) with those of the polymerase chain reaction-sequence-based typing. An NGS technology platform for 36 blood group systems genotyping was successfully established, which has the characteristics of high accuracy, high throughput, and wide coverage.

Red Blood Cell Membrane-Coated Nanoparticles Enable Incompatible Blood Transfusions.

Blood transfusions save lives and improve health every day. Despite the matching of blood types being stricter than it ever has been, emergency transfusions among incompatible blood types are still inevitable in the clinic when there is a lack of acceptable blood types for recipients. Here to overcome this, a counter measure nanoplatform consisting of a polymeric core coated by a red blood cell (RBC) membrane is developed. With A-type or B-type RBC membrane camouflaging, the nanoplatform is capable of specifically capturing anti-A or anti-B IgM antibodies within B-type or A-type whole blood, thereby decreasing the corresponding IgM antibody levels and then allowing the incompatible blood transfusions. In addition to IgM, the anti-RBC IgG antibody in a passive immunization murine model can likewise be neutralized by this nanoplatform, leading to prolonged circulation time of incompatible donor RBCs. Noteworthily, nanoplatform made by expired RBCs (>42 days stored hypothermically) and then subjected to lyophilization does not impair their effect on antibody neutralization. Most importantly, antibody-captured RBC-NP do not exacerbate the risk of inflammation, complement activation, and coagulopathy in an acute hemorrhagic shock murine model. Overall, this biomimetic nanoplatform can safely neutralize the antibody to enable incompatible blood transfusion.

Immunohematology studies in the Republican Clinical Hospital in the conditions of centralized laboratory service

The article analyzes the effectiveness of immunohematology studies conducted in the clinical diagnostic laboratory of the State Budgetary Healthcare Institution «Republican Clinical Hospital named after G. G. Kuvatov» of the Republic of Bashkortostan for three years (2019-2021) in the context of the centralization of laboratory services. It is shown that the studies are carried out at the modern level using new technologies, which significantly improves the quality of the studies and reduces the risk of incompatible blood transfusions to patients.

PREVALENCE OF BLOOD GROUPA2 AMONG GROUPAAND AB DONORS

The ABO blood group antigens are clinically signicant and their discovery by Landsteiner in 1900 paved way for the performance of safe blood transfusions. These antigens are characterized by their distinct carbohydrate structures attached to the glycoprotein or glycolipid membranes of red blood cells (RBCs). Their expression can also be detected on various human cell and tissue surfaces including sensory neurons, vascular endothelium and platelets. [1] Subgroups of the ABO antigens occur and are characterized by reduced quantities of the antigens on the RBCs and saliva of secretors. [2] Landsteiner & Levine subdivided blood group A into their principal subgroups, A1 and A2. The presence of Asubgroups is due to genetic variations in the coding region which leads to diminished amounts of A substance and higher amounts of H substance on red blood cells. There are weaker subgroups than A2 which do not frequently occur but when present; they show a characteristic decreased Aantigen sites on their RBC and a corresponding increased H antigen activity. [3] The difference between subgroups A1 and A2 is seen in their reactivity with the Dolichos biflorus lectin. The Dolichos lectin specically agglutinates A1 cells, leaving the A2 cells unagglutinated. The ABO antibodies occur naturally in the sera of individuals who do not have the corresponding antigens and can cause haemolysis in-vivo. They are mostly immunoglobulin M (IgM). These antibodies through complement activation can cause severe, life-threatening transfusion reactions due to incompatible ABO blood transfusions. Anti-A1 antibody appears as an atypical cold agglutinin in the sera of few people with group A2 or A2B who do not have the corresponding antigen.[4] One to eight percent of persons with blood group A2 and about 22-35% of persons with group A2B have serum anti-A1. These antibodies may cause discrepancies in ABO blood grouping which can further result in HTR.[5] Rare cases of haemolytic transfusion reaction due to anti-A1 have been reported.[4] It is estimated that about 80% of individuals with antigen A are A1 while the remaining 20% are A2. [5] Among Indians, the frequency of subgroup A2 among group A individuals is 6.58% whiles that of A2B among group AB is 8.99%.[6] Knowledge of the frequency and distribution of blood subgroup A2 will help to enhance blood compatibility testing, population genetic studies, investigation of transfusion reactions, studying disease associations and resolving some medico-legal issues.[7]

A CNN-LASSO ensemble classification model for incomplete antibody reactants screening in coombs test.

Precise classification of incomplete antibody reactants (IAR) in the Coombs test is the primary means to prevent incompatible blood transfusions. Currently, an automatic and contactless method is required for accurate IAR classification to avoid human error. We present an ensemble learning algorithm that integrates five convolutional neural networks and the least absolute shrinkage and selection operator (LASSO) regression algorithm into an IAR intensity classification model. A dataset including 1628 IAR and corresponding labels of IAR intensity categories ((-), (1+), (2+), (3+), and (4+)) was used. We trained the ensemble model using 1302 IAR and validated its performance using 326 IAR. The optimal ensemble model was used to assist immunologists in classifying IAR. The chord diagrams based on the human-machine interaction were established. The ensemble model achieved 98.8%, 98.4%, 99.7%, 99.5%, and 99.4% accuracies in the (-), (1+), (2+), (3+), and (4+) categories, respectively. The results were compared with those of manual classification by immunologists (average accuracy: 99.2% vs. 75.6%). Using the model, all three immunologists achieved increased accuracy (average accuracy: +8.4%). The proposed algorithm can thus effectively improve the accuracy and efficiency of IAR intensity classification and facilitate the automation of haemolytic disease screening equipment.

Whole blood transfusion and paroxysmal nocturnal haemoglobinuria meet again: Minor incompatibility, major trouble.

The field of transfusion medicine started out with whole blood transfusion to treat severe anaemia and other deficiencies, and then transitioned to component therapy, largely leaving the practice, and experiences, of whole blood transfusions behind. Currently, the field is circling back and whole blood is gaining ground as an alternative to massive transfusion protocols. Herein we describe a severely anaemic paroxysmal nocturnal haemoglobinuria (PNH) patient initially suspected of suffering from renal haemorrhage, receiving a standard low-titre group O whole blood transfusion during pre-hospital transportation. Following the transfusion, the patient suffered a clinically unmistakable haemolytic transfusion reaction requiring supportive treatment in the intensive care unit. Clinical observations are consistent with an acute haemolytic reaction. The haemolysis was likely due to minor incompatibility between the plasma from the transfused whole blood and the patient's PNH red cells. Recovery was uneventful. This revealed an unappreciated contraindication to minor incompatible whole blood transfusion, and prompted a discussion on the distinction between whole blood and erythrocyte concentrates, the different indications for use and the importance of emphasizing these differences. It also calls attention to patient groups where minor incompatibility can be of major importance.

Attitudes of American adult women toward accepting RhD-mismatched transfusions in bleeding emergencies.

There is an increasing literature demonstrating the benefits of prehospital and early in-hospital transfusions. RhD-positive products might only be available during these phases, which could pose consequences for future pregnancies if D-alloimmunization occurs. This survey measured the willingness of females to accept urgent but incompatible transfusions in light of the potential for future pregnancy complications. A survey was designed to assess the willingness of females ≥18 years of age to accept urgent incompatible transfusions when different absolute risk reductions in maternal mortality were presented along with a static rate of 0.3%-4.0% risk of harm to future pregnancies. The survey was sent electronically to women who are part of the Washington University Research Enhancement Core database. A total of 4896 delivered survey email invitations were distributed and 325 (6.6%) responses were received; 16 responses were excluded leaving 309 responses for analysis. Most of the responding women were White, college-educated, and lived in Missouri. At least 90% of the respondents would accept an urgent incompatible transfusion when the absolute risk reduction in maternal mortality was ≥4%. Women without a college degree, who lived in Illinois, who were not able to have children appeared to be less willing than their counterparts to receive an incompatible transfusion when the absolute risk reduction in maternal mortality was low. This survey demonstrated that adult women are highly likely to be open to accept urgent incompatible blood transfusions during a bleeding emergency when the absolute risk reduction in maternal mortality was ≥4%.

Prevalence of Irregular Red Cell Antibodies in Healthy Blood Donors at a Stand-Alone Blood Centre in Gujarat

Background: Blood transfusion therapy involves multiple steps to ensure selection of safe blood component for transfusion. This includes testing for infectious markers, full ABO compatibility, free from any irregular red cell antibodies especially which are reacting at wide thermal amplitude and acceptable donor's red cell survival rates without destruction of recipient's red cells. Objective: This study was aimed to assess prevalence and type of irregular red cell antibodies in a large number of blood donor population at a standalone blood centre in Gujarat. Methods: This retrospective observational study included blood donor samples for antibody screening from January 2018 to March 2022. A total of 2,16,576 healthy blood donors including 2,00,493 (92.57%) males and 16,083 (7.43%) females were screened. Results: The prevalence of irregular red cell antibodies was 0.03 per cent in our donor population. Of the total 66 donors with red cell antibodies, 53(80.30%) had alloantibodies, 8(12.12%) had autoantibodies and 6 donors (9.09%) showed positive antibody screening with inconclusive results. We also found one case of cold antibody. Conclusion: Alloimmunization to red cell antigens is a challenging task for current transfusion practices. The antibody screening in blood donors may improve the quality and safety of blood transfusion in the recipients. It also reduces the risk of complications from incompatible blood transfusions. Keywords: antibody screening, allo-antibody identification, autoantibody, safe blood transfusion, hemolytic transfusion reaction.

Unexpected antibody against the high-prevalence P antigen before cardiac surgery.

P is a high-prevalence antigen present in 99.9 percent of the population and is fully developed at birth. P- individuals form naturally occurring antibodies against P, which are often of immunoglobulin (Ig)M and/or IgG type, very potent in complement activation, and able to cause serious intravascular hemolytic transfusion reactions. Some people with anti-P have the rare P1 k phenotype, which lacks P in the presence of P1 and Pk. Blood transfusion in patients with anti-P is challenging, as is described here. A male patient without a history of blood transfusion was admitted for a planned cardiac surgery. The preoperative ABO blood group could not be determined because of unexpected reactions in the reverse grouping, and all red blood cells (RBCs) in the antibody detection test were positive, except for the autocontrol. Further analysis of the patient's sample confirmed the presence of the P1 k phenotype, and anti-P was identified. If transfusion was needed, P- blood would be required, and the only P- RBCs available were at the national Sanquin Bank of Frozen Blood. These units are limited, expensive, and only available for 48 hours after thawing. In the case of massive blood loss, first ABO and Rh-compatible units should be transfused, followed by P- units after the bleeding stops. In our case, the surgery was conducted without transfusion. This case illustrates the importance of preoperative ABO blood group testing and antibody screening in cases where blood loss can be expected. In recent years, more focus has been put on patient blood management. A good collaboration between the local laboratory, surgery department, and dedicated blood transfusion laboratory is critical to prevent unnecessary incompatible blood transfusions with potentially serious outcomes.

Glycoproteomic and Phenotypic Elucidation of B4GALNT2 Expression Variants in the SID Histo-Blood Group System.

The Sda histo-blood group antigen (GalNAcβ1-4(NeuAcα2-3)Galβ-R) is implicated in various infections and constitutes a potential biomarker for colon cancer. Sd(a−) individuals (2–4% of Europeans) may produce anti-Sda, which can lead to incompatible blood transfusions, especially if donors with the high-expressing Sd(a++)/Cad phenotype are involved. We previously reported the association of B4GALNT2 mutations with Sd(a−), which established the SID blood-group system. The present study provides causal proof underpinning this correlation. Sd(a−) HEK293 cells were transfected with different B4GALNT2 constructs and evaluated by immunostaining and glycoproteomics. The predominant SIDnull candidate allele with rs7224888:T>C (p.Cys406Arg) abolished Sda synthesis, while this antigen was detectable as N- or O-glycans on glycoproteins following transfection of wildtype B4GALNT2. Surprisingly, two rare missense variants, rs148441237:A>G and rs61743617:C>T, found in a Sd(a−) compound heterozygote, gave results similar to wildtype. To elucidate on whether Sd(a++)/Cad also depends on B4GALNT2 alterations, this gene was sequenced in five individuals. No Cad-specific changes were identified, but a detailed erythroid Cad glycoprotein profile was obtained, especially for glycophorin-A (GLPA) O-glycosylation, equilibrative nucleoside transporter 1 (S29A1) O-glycosylation, and band 3 anion transport protein (B3AT) N-glycosylation. In conclusion, the p.Cys406Arg β4GalNAc-T2 variant causes Sda-deficiency in humans, while the enigmatic Cad phenotype remains unresolved, albeit further characterized.

Acute Intravascular Hemolysis in the Critical Phase of Severe Dengue

Background: Dengue and severe dengue have various hemorrhagic manifestations ranging from mild presentations such as petechiae, bleeding from injection sites, ecchymosis, and gum bleeding to severe presentations like major mucosal bleeding such as hematemesis, melena, menorrhagia, and concealed internal bleeding. Common causes of anemia in dengue are due to blood loss (secondary to thrombocytopenia and/or coagulopathy), transient suppression of the bone marrow, and rarely, hemolytic anemia. Clinical Description: We describe a 5-year-old boy who presented to us in the critical phase of severe dengue with features of capillary leakage and cola-colored urine. Salient investigation reports were anemia, thrombocytopenia, normal reticulocyte count, absence of coagulopathy, indirect hyperbilirubinemia, deranged transaminase, highly elevated lactate dehydrogenase, and low haptoglobin levels, and hemoglobinuria, suggestive of acute intravascular hemolysis (AIVH). Autoimmune and microangiopathic hemolytic anemia, malaria, ingestion of dyes, snake bite, Glucose 6 phosphate dehydrogenase deficiency, and incompatible blood transfusions were excluded. Thus, the final diagnosis was severe dengue with hemolytic anemia and AIVH. Management: Oxygen delivery by the Heated Humidified High-Flow Nasal Cannula, strict input/output charting, appropriate fluid therapy, and diuretic infusion were the mainstays of management in an intensive setting. The aim was to maintain ventilation, perfusion, balance hydration, achieve optimal urine output and prevent fluid overload. Conclusion: Clinicians should consider Dengue as a possible cause for AIVH in children with severe dengue and cola-colored urine.

An Analysis of Blood Grouping Discrepancies : Study From Tertiary Hospital based Blood Bank in Vadodara

Background:-ABO and Rhesus blood group system is considered as clinically significant blood groupsystems in transfusion practice . A feature of the ABO system is the regular occurrence of anti A and anti B inthe absence of the corresponding red cell antigen. A Discrepancy exists when results of forward testing doesnot match with reverse testing. Blood donors and patients must be correctly ABO and Rh grouped becausetransfusing ABO incompatible blood transfusions which may lead even death of patient.Aims and Objectives To assess the incidence and cause of blood grouping discrepancies in Blood Bankat Tertiary care teaching hospital during Jan 2019 to December 2019.Methods : Forward and reverse grouping were performed on blood samples from inpatients ,outpatientsand donors during the study period. ABO discrepancies were studied with their clinical details to group theirdiscrepancies and resolve them with suitable steps.Results: A total of 10,048 (patients and donors) who satisfied inclusion criteria were included and ABOtyped among which there were 55 discrepancies were observed (15 donors and 35 patients). The problemin patients was due to expression of weak antigens. The problem in patients were due to clinical conditions,the most common being autoimmune haemolytic anaemia.Conclusions: The ABO blood group discrepancy reported in present study is 0.49%. The study helped todetermine the incidence and causes of discrepancy encountered in tertiary care hospital. Discrepant resultsshould be recorded, and resolved by suitable measures and correct ABO & Rh Blood group should bereleased to avoid any mismatched transfusions.

ABO AND RHESUS BLOOD GROUP DISTRIBUTION AMONG INDEGEOUS PEOPLE IN SOUTH SUMATERA

Background: ABO and Rhesus blood group systems are genetic markers that are useful in the study of human populations, in addition, they play an important role in incompatible blood and marital transfusions. The purpose of this research was to describe ABO And Rhesus Blood Group Systems of Health Polytechnic Palembang Students as Indegeous People in South Sumatera of 2019
 Methods: The respondents were 187 students of Palembang Health Polytechnic. This type of research was descriptive with a cross sectional approach. Taken by total sampling technique
 Results:The results showed Komering tribal students were A (38.1%), B (23.8%), O (28.6%), and AB (9.5%). The Palembang tribe A (26.8%), B (32.1%), O (30.4%), and AB (10.7%). The Gumai tribe A (66.7%), B (0.0%), O (33.3%), and AB (0.0%). The Semendo tribe A (33.3%), B (33.3%), O (33.3%), and AB (0.0%). The Lintang tribe A (33.3%), B (0.0%), O (33.3%), and AB (33.3%). The Kayu Agung tribe A (27.3%), B (9.1%), O (45.5%), and AB (18.2%). The Lematang tribe A (28.6%), B (42.9%), O (14.3%), and AB (14.3%). The Ogan tribe A (30.0%), B (20.0%), O (37.5%), and AB (12.5%). The Pasemah tribe A (33.3%), B (33.3%), O (33.3%), and AB (0.0%). The Sekayu tribe A (29.4%), B (35.3%), O (29.4%), and AB (5.9%). The Rawas tribe A (50.0%), B (0.0%), O (50.0%), and AB (0.0%). The Banyuasin tribe A (30.0%), B (30.0%), O (20.0%), and AB (20.0%). All samples had Rhesus positive (+) blood group with a percentage of 100.0%
 Conclusion: Therefore, it can be concluded that the highest percentage of the distribution is blood group O, while the lowest is blood blood group AB, all of them are Rhesus positive (+)

Transfusion of Incompatible Blood

Transfusion of incompatible blood is mostly accidental rather than therapeutic. However, at times, we are faced with challenges wherein we need to transfuse incompatible blood. Once such situation arise in autoimmune hemolytic anemia (AIHA) if it leads to severe anemia. Here, we report a case of AIHA with hypoxia and hemodynamic instability requiring urgent transfusion and later diagnosed to have systemic lupus erythematosus. In AIHA, typing and crossmatching are very difficult. Therefore, one should use the least incompatible blood if transfusion is indicated for the risk of hemolysis.

Development of a Semi-automated Monocyte Monolayer Assay (MMA) to Determine the Clinical Significance of Red Cell Alloantibodies

Abstract BACKGROUND One risk of allogeneic blood transfusion is the development of alloantibodies against red blood cell (RBC) antigens not found on the recipient’s RBC. The monocyte monolayer assay (MMA) is an in vitro model which has been used to determine the clinical significance of alloantibodies and predict post-transfusion RBC survival. We aimed to develop a semi-automated procedure to reduce assay time and facilitate improved patient management. METHODS PBMCs isolated using Sepmate tubes (STEMCELL Technologies) were added to Lab-Tek 8-well chamber slides (37°C, 1 hr, CO2). Antigen matched RBC were sensitised with plasma with known anti-RBC antibodies (anti-D n=3, anti-Yta n=4) (37°C, 1 hr, CO2). A modified Wright-Giemsa staining protocol was performed (Aerospray Hematology Pro 2 stainer, ELITechGroup) and the proportion of bound and/or phagocytosed RBC was determined via microscopy (>5% considered clinically significant). RESULTS The introduction of PBMC isolation using sepmate tubes and automated cell staining reduced technical requirements, improved assay reproducibility and reduced assay time by >2 hours. For the alloantibodies tested, 67% of the anti-D and none of the anti-Yta were clinically significant. CONCLUSIONS We developed a MMA with improved reproducibility and reduced turnaround time. This assay will improve blood transfusion safety and facilitate better patient management by reducing the risk of incompatible blood transfusion.

Instructional Hematology for Pre‐Health Undergraduates

At Michigan State University (MSU), the physiology department’s lab course for pre‐health professionals places an emphasis on laboratory exercises relevant to healthcare and the development of data analysis, professional development, and problem solving skills. As such, the goal of the hematology laboratory experience is to help students understand the ripple effect of hematology and how it can be extended to other fields of medicine. This is done by exposing students to the collection of blood samples and related laboratory tests that can be a typical part of a health screening or onsite wellness visit. Even for those students who do not become hematologists, it is important to maintain current knowledge of the best practices regarding the treatment and testing required for the best patient service and understand how various blood disorders affect certain populations.We promote hematology learning through five blood testing stations in addition to microscope analysis. The five blood tests performed are hematocrit, blood typing, total lipid panel, prothrombin time and international normalized ratio (PT‐INR), and hemoglobin. Students will perform each of these blood tests with their own samples and are guided to the interpretation of each measurement with provided clinical standards. We also include the microscopic analysis of five live patient samples of blood with conditions including, sickle cell anemia, eosinophilia, acute myelogenous leukemia, and lymphoma. In analyzing each of these tests, students are tasked with relating their own data to overall health and clinical relevance. The learning objectives associated with these tests include the demonstration of safe handling of blood using Universal Precautions, among the ability to describe and recognize typical and pathologic values found in common blood tests. They are also required to explore the supporting physiology, such as the phases of hemostasis and consequences of incompatible blood transfusions. Students are able to practice their professional skills by teaching each other how to perform these tests after they have watched and performed their own, modeling the “see one, do one, teach one” pedagogy often found in clinical settings. Additionally, with the results and permission of our students, we are able to gather baseline blood data for this healthy age group and seek to compile and share these values as a composite look at typical data for this specific group.

Autoimmune hemolytic anemia in hospitalized patients: 450 patients and their red blood cell transfusions.

Autoimmune hemolytic anemia (AIHA) is a rare disease in which autoantibodies target red blood cells (RBCs), leading to anemia that ranges from no symptoms to severe life-threatening hemolysis. Little is known about the severity of anemia, blood transfusion efficiency and risk of transfusion-related reactions among hospitalized AIHA patients, especially in those with incompatible RBC transfusions.A retrospective study was conducted among hospitalized AIHA patients from January 2009 to December 2015 in a large tertiary care medical center in southwest China.A total of 450 AIHA hospitalized patients were recruited, of whom 97.3% had warm AIHA, 30.3% had primary AIHA, and 90.7% were treated with corticosteroids. On admission, approximately 3% of patients had an hemoglobin (Hb) <30 g/L, 34% had an Hb between 30 and 59.9 g/L, and 46% had an Hb ranging from 60 to 89.9 g/L. A total of 2509.5 U RBCs were transfused to AIHA patients, and 14 transfusion-related adverse reactions were recorded, without any hemolytic transfusion reactions. With an average transfusion trigger of 52.0 ± 9.3 g/L, 59.7% of the patients received RBCs, and 55.8% of the transfusions were viewed as effective. Least incompatible RBCs were given in 39% of the transfusions, but the transfusion efficiency did not significantly decrease with these incompatible blood transfusions (P = .253). Primary AIHA patients with a nadir Hb of approximately 40 to 50 g/L during their hospital stay had the highest rate of remission and did not require a different total number of RBC transfusions (P = .068) or length of hospitalization (P = .194) compared to other groups with nadir Hb values <30 g/L, ≥30 and <40 g/L, ≥50 and <60 g/L, and ≥60 g/L.One-third of AIHA patients suffered from severe anemia during hospitalization, and transfusions, even with incompatible RBCs, were safe and efficient. However, transfusion triggers between 40 and 50 g/L seemed to benefit the most patients by alleviating the RBC destruction caused by autoantibodies, and a restrictive transfusion strategy was beneficial in AIHA patients.

Prevalence of red blood cell antibodies in whole blood donors: A single-centre experience in north India.

Background & objectives:Blood transfusion therapy involves multiple steps to ensure selection of safe blood component for transfusion. This includes testing for infectious markers, full ABO compatibility, free from any clinically significant red cell antibodies and acceptable donor's red cell survival rates without destruction of recipient's red cells. The red cell antibodies present in healthy blood donors can cause severe haemolytic transfusion reaction, especially in massive blood transfusion recipients and paediatric patients. Hence, screening of red cell antibodies in donor blood is important to provide compatible blood products and to avoid haemolytic transfusion reactions in susceptible patient population. This study was planned to assess prevalence, aetiology and type of unexpected red cell antibodies in a large number of whole blood donor population in north India.Methods:This three-year prospective observational study included blood donor samples for antibody screening from January 2015 to December 2017. A total of 166,803 healthy blood donors including 156,128 (93.6%) males and 10,675 (6.4%) females were screened.Results:The prevalence of red cell antibodies was 0.17 per cent in our donor population. Of the total 286 donors with red cell antibodies, 248 (86.7%) had alloantibodies, 30 (10.5%) had autoantibodies and eight donors (2.8%) showed positive antibody screening with inconclusive results.Interpretation & conclusions:Alloimmunization to red cell antigens is a challenging task for current transfusion practices. The antibody screening in blood donors may improve the quality and safety of blood transfusion in the recipients. It also reduces the risk of complications from incompatible blood transfusions.

Frequency of dog erythrocyte antigen 1 blood group and risk of incompatible transfusion in dogs of different breeds and mongrels from the city of Salvador - BA, Brazil

The dog erythrocyte antigen 1 (DEA 1) is the most immunogenic blood group in dogs, and blood transfusions may trigger some undesirable effects in veterinary patients, which are directly associated with incompatible transfusions. The present study aimed to investigate the frequency of positive DEA 1 blood group in blood donor dogs from a blood bank in Salvador, Bahia, Brazil, and also to calculate the risk of managing incompatible blood in both first and second transfusion. A number of 203 dogs of different breeds, aged between 1 and 8 years, weighing 28 kg, with no degree of kinship and of both sexes in Salvador - BA, Brazil were evaluated to investigate the blood type DEA 1 frequency, by means of chromatography and flow cytometry tests for blood typing. The risk of incompatible blood transfusion in either a first or a second transfusion was also calculated. The frequency of the DEA 1 group ranged from 0% to 100% in various breeds, but with a mean positivity of 62.07% (126/203). And the lowest risk of an DEA 1 negative animal receiving DEA 1 positive blood within the group of animals evaluated was 0.92% at a first transfusion; and the risk of the same animal receiving incompatible blood for the DEA group 1 in the second transfusion was 0.008%. The highest risk of an DEA 1 negative animal receiving DEA 1 positive blood from these animals was 69.12%; and the risk of receiving incompatible blood for DEA 1 was 47.77%. In conclusion, the frequency of the DEA 1 group varied between the studied breeds and the risk of incompatible blood transfusions varies according to donor and recipiente breeds, but this can be overridden if blood typing tests are performed along with the cross-reaction test for compatibility.