Compatible Blood Research Articles

Evaluation of Anti-k Antibody in a Patient Undergoing Redo Sternotomy

Abstract Introduction/Objective Introduction: The Kell blood group system, discovered in 1946, holds paramount significance in transfusion medicine and hemolytic disease of the newborn (HDN). Named after Mrs. Kelleher, who exhibited anti-Kell antibodies resulting in HDN, this system comprises 25 antigens, with the original K antigen retaining primary importance. Additionally, Levine et al. identified anti-Cellano, now known as anti-k, presenting an antibody antithetical to anti-K. Methods/Case Report Case Presentation: A 60-year-old male with a history of bioprosthetic aortic valve insufficiency, pulmonary homograft stenosis, and recurrent aortic insufficiency presents for a fourth redo sternotomy for root and ascending aorta replacement. Preoperative assessment revealed a positive antibody screen for anti-k, a clinically significant antibody associated with decreased survival of transfused red blood cells (RBCs). Given limited compatible blood units available, efforts are underway to secure additional donations before the scheduled surgery on 2/22/24. The patient’s medical history indicates no recent blood transfusions or iron therapy, with the last transfusion in 1996. He is anticoagulated with warfarin for mechanical valve and atrial fibrillation, necessitating preoperative bridging with Lovenox injections. Methods The patient’s antibody screen and initial panel demonstrated pan-reactivity with 3+ reactivity, suggesting an antibody targeting a high-frequency antigen. Further testing using polyethylene glycol (PEG) confirmed the presence of anti-k, supported by negative reactions to additional K-negative cells. The absence of other clinically significant antibodies was verified using 0.2 M Dithiothreitol (DTT) modified cells. Results (if a Case Study enter NA) NA Conclusion Conclusion: The identification of anti-k antibody underscores the critical role of preoperative antibody screening in mitigating transfusion-related complications, particularly in patients requiring complex surgical interventions. Collaborative efforts between clinical teams and transfusion medicine specialists are imperative to ensure adequate blood product availability and optimize patient outcomes.To prevent further exposure, it is recommended that patients with rare antibodies carry an Antibody ID card indicating the rare antibody they possess.k antigen blood donors are underrepresented in the general donor pool. It is recommended to develop a systematic recruitment for k antigen donors.

Red Blood Cell (RBC) Antigen Confirmation Workflow – A Positive Impact at an Academic Medical Center

Abstract Introduction/Objective Introduction: Blood group antigens, present on the surface of red blood cells (RBCs), play a crucial role in transfusion medicine. These antigens are recognized serologically and form the basis of RBC phenotyping. Understanding the significance of antigen-negative RBCs is essential for mitigating the risk of hemolytic transfusion reactions and hemolytic disease of the fetus and newborn (HDFN). This study aims to assess the impact of implementing a new RBC antigen confirmation workflow on transfusion service efficiency and patient outcomes. Methods/Case Report Method: The study involved collaboration between our Transfusion Services Department (TS), the Blood Center supplier, and the Apheresis department. A comprehensive review of historical practices and FDA recommendations regarding RBC antigen labeling was conducted. Changes were implemented to streamline antigen confirmation testing and labeling processes. The impact on TS workload, turnaround time, and patient care metrics was evaluated. Results (if a Case Study enter NA) Results: Implementation of the new RBC antigen confirmation workflow led to a significant reduction in antigen confirmation tests performed by TS, with a 607% decrease observed from 2020 to 2023. Concurrently, the workload for reference lab workups increased by 337% over the same period. This shift in workload distribution allowed TS staff to focus more on patient reference workup cases and case review. The improved workflow efficiency resulted in enhanced turnaround times for providing patients with antigen-negative RBCs, ultimately improving the patient experience. Conclusion Conclusion: The adoption of the new RBC antigen confirmation workflow has resulted in compliance with FDA labeling requirements, efficient utilization of TS staff resources, and decreased turnaround times for blood delivery. These improvements have positively impacted patient care by ensuring timely access to compatible blood products. Future steps include developing reports to track turnaround time for patients with special blood product needs and continuing collaboration with the blood supplier and the Apheresis department to optimize inventory management and transfusion processes.

Perioperative selection of blood and components for substitution: Immunohaematological assessment of immunization risk and methods for selection of optimally compatible blood

The aim of this study is to assess the risk for immune and hematologic adverse events in perioperative transfusion of blood components. Our second goal is to propose methods for the selection of an optimally compatible donor in order to limit the negative impact of complications following blood component transfusion on the hospital outcome of patients admitted to clinics of general, gastrointestinal, thoracic, and vascular surgery. The largest group of patients included in this study were patients with gastrointestinal disorders (614 patients; 31%) and patients with diseases of the organs of the blood and lymphatic system (589 patients; 30%). This was followed by patients with diseases of the skin and subcutaneous tissue (368 patients; 18%) and patients with benign and malignant neoplasms (365 patients; 18%). The remaining 65 patients (3%) were diagnosed with diseases of the endocrine system, trauma patients, and patients with genitourinary disorders. The methods used for optimal selection of compatible blood components in this study are enzyme tests, Coombs tests, and tests in agglutinating medium. The study shows that clinically significant antibodies, which could provoke a post-transfusion hemolytic reaction, were detected in 4.3% of the screened patients. In the majority of patients, the specificity of antierythrocyte antibodies cannot be established. For those patients where the specificity of anti-erythrocyte antibodies could be established, the type of antibody and the antigen system to which it belonged were as follows (in descending order): 1. Anti-erythrocyte antibodies belonging to the Rh system: 37% (n = 17) of all screened patients (1.6% of all patients), including anti-E type (5 patients), anti-D (8 patients), anti-C-1, anti-C (2 patients), and anti-Cw (1 patient). 2. In 3 (6% or anti-erythrocyte antibodies belonging to other erythrocyte antigen systems—Kidd-1 patients, Lewis-2 patients—6% of the screened patients (0.3% of all patients). 3. In 57% (n = 26) of those screened (2.4% of all patients), alloantibodies without any known specificity were identified. The largest number of identified antibodies were directed against the D antigen belonging to the Rh system. Most of the anti-D alloantibodies found in Rhesus D (-) negative patients with no history of prior transfusion of D (+) positive red blood cell (RBC) concentrate possibly have resulted from prior Rh isoimmunization during pregnancy, provided that anti-D antibodies persist for a long time after birth—in some of the studied patients, 15–20 or more years. A greater number of alloimmunizations were found in women—28 (61%), compared to men—18 (39%), due to previous sensitization with different blood group antigens during pregnancy. This study shows that timely diagnosis is essential for the selection of appropriate RBC concentrate, for the avoidance of adverse reactions, and for the improvement of hematological parameters after transfusion of blood components. Graphical abstract:

Molecular genotyping versus serological diagnosis for RH blood group typing in sickle cell patients

ABSTRACT Objectives High rate of alloimmunization in sickle cell disease (SCD) patients poses a significant challenge in finding compatible blood unit. Accurate determination of the blood group genotype of them can help reduce the alloimmunization risk. Tetra ARMS PCR is a novel method that has been utilized recently to investigate SNPs in diseases in a fast and reliable way. Methods Our study included 104 SCD and sickle thalassemia (Sβ) patients referred to Baghaei-2-Hospital of Ahvaz in 2019 using a nonrandom sampling method. Blood samples were collected for serological and molecular tests. Rh genotyping was performed using Tetra ARMS PCR and compared with the serological results. Results Based on the Tetra ARMS PCR method, out of 104 patients, 7 (6.7%) were d/d, 40 (38.5%) were D/d, 57 (54.8%) were D/D, 25 (24%) were C/C, 59 (56.7%) were C/c, 20 (19.3%) were c/c, 4 (3.8%) were E/E, 25 (24%) were E/e, and patients 75 (72.2%) were e/e. There were discrepancies in the serological and molecular results for 11 patients. Conclusion Use of Tetra ARMS PCR in combination with serological methods for determining the Rh blood group system in donors and transfusion-dependent patients represents a remarkable transformation in the field of immunohematology.

Red blood cell alloimmunization in transfused patients with myelodysplastic syndromes: a retrospective study from northern China.

Alloimmunization against red blood cell (RBC) antigen is an important concern in myelodysplastic syndromes (MDSs) patients with chronic transfusion, causing potential risk for hemolytic reaction and limited supply of compatible blood. However, there is little data addressing RBC alloimmunization in this patient cohort among the Chinese population. This study aims to evaluate the incidence, specificity of antibodies, and RBC units transfused before antibody formation and its significance in a population of patients consistently receiving RhD-matched RBC units. We retrospectively reviewed the transfusion and clinical information of all transfused patients with MDS enrolled in our hospital from 2012 to 2022. The cumulative incidence of alloimmunization was analyzed by a Kaplan-Meier plot. Alloimmunization incidence was compared based on different transfused RBC units using the log-rank test. A total of 103 patients with MDS were included in this study; alloantibody formed in 8 (7.8%) patients. Before reaching 32 RBC units, 87.5% of the alloimmunized patients had developed their alloantibodies. All but 1 of the alloantibodies developed were antibodies to Rh antigens. The RBC transfusion intensity and frequency were significantly higher following alloimmunization in the alloimmunized patients (P=.008, P=.008, respectively). The antibodies detected mostly involve the Rh system among MDS patients in China. The alloimmunization tended to occur early prior to reaching 32 RBC units in patients with MDS. Rh antigen matching should be considered early in the patient's transfusion history and completed before receiving 32 RBC units.

Transfusion support and pre-transfusion testing in autoimmune haemolytic anaemia.

Autoimmune haemolytic anaemia (AIHA) is characterized by an increased destruction of red blood cells due to immune dysfunction and auto-antibody production. Clinical manifestations are mainly related to anaemia, which can become life-threatening in case of acute haemolysis. Aiming at counterbalancing severe anaemia, supportive treatments for these patients frequently include transfusions. Unfortunately, free serum auto-antibodies greatly interfere in pre-transfusion testing, and the identification of compatible red blood cell units for AIHA patients can be challenging or even impossible. Problems faced in pre-transfusion testing often lead to delay or abandonment of transfusions for AIHA patients. In this review, we discuss publications concerning global transfusion management in AIHA, with a focus on pre-transfusion testing, and practical clues to manage the selection of transfusion units for these patients. Depending on the degree of transfusion emergency, we propose an algorithm for the selection and laboratory testing of units to be transfused to AIHA patients.

Distribution Characteristics of Rh Phenotype and Feasibility of Compatible Blood Transfusion in Pregnant and Postpartum Women

To analyze the distribution characteristics of Rh phenotype in pregnant and postpartum women in Chongqing area, and to explore the clinical significance of Rh phenotype in pregnant and postpartum women and the feasibility of Rh phenotype compatible blood transfusion. The ABO blood group and Rh phenotype of 65 161 pregnant and postpartum women were detected by microcolumn gel method, and 48 122 males in the same period were taken as controls. The data were analyzed by Chi-square test. There were 112 870 cases (99.64%) of RhD+ in 113 283 samples. In RhD+ cases, CCDee (48.39%) and CcDEe (32.88%) were the main phenotypes. The first case of D-- phenotype in Chongqing area was detected. 413 cases (0.36%) of RhD- were detected, with ccdee (52.78%) and Ccdee (33.41%) as the main phenotypes. Compared with RhD- group, RhD+ group showed statistically significant difference in Rh phenotype distribution (P < 0.01). Among 65 161 maternal samples, the positive rate of 5 antigens of Rh blood group from high to low was D > e > C > c > E, and there was no significant difference compared with male samples (P >0.05). There was no significant difference in the distribution of Rh phenotype between males and pregnant/postpartum women, as well as between pregnant/postpartum women with different ABO blood groups (P >0.05). In pregnant and postpartum women, there was no significant difference in distribution of Rh phenotype among the normal pregnancy population, the population with adverse pregnancy history, the population using human assisted reproductive technology (ART) and the population with infertility (P >0.05). There was no significant difference in the distribution of Rh phenotype between the 4 populations mentioned above and the inpatients in the local general Grade A hospitals and the blood donors (P >0.05). In RhD positive pregnant and postpartum women, the probability of finding compatible blood for CcDEe phenotype was 100%, the probability of finding compatible blood for CCDee, CcDee and CCDEe phenotypes was 45%-60%, the probability of finding compatible blood for ccDEE, ccDEe and CcDEE phenotypes was 5%-10%, and the probability of finding compatible blood for other phenotypes was lower than 0.5%. The supply of blood with CCDee and ccDEE phenotypes can meet the compatible transfusions requirements of 7 Rh phenotypes in more than 99% of patients. Rh phenotype detection should be carried out for pregnant and postpartum women, and it is feasible to carry out Rh phenotype-matched or compatible blood transfusion for pregnant and postpartum women who need blood transfusion.

Red Cell Alloimmunisation Among Sickle Cell Disease and Thalassemia Patients Following Rh- and K-Matched Red Cell Transfusion in Southwestern Saudi Arabia: A Multicenter Study.

Alloimmunisation remains a major consequence of blood transfusion among sickle cell disease (SCD) and thalassemia patients due to the exposure to non-self-red blood cell (RBC) antigen. The complication is associated with transfusion reactions and delayed transfusion procedure because of the difficulty of finding compatible blood. This study aims to determine the prevalence of alloimmunisation to RBC and alloantibody specificities among SCD and thalassemia patients in, an endemic area of SCD and thalassemia, Jazan province of Saudi Arabia, from three major hospitals. This is a retrospective, multicenter cross-sectional study conducted on 1027 patients with SCD and thalassemia, which received Rh/K matched transfusions in 2019 in the three centers. Demographic data and medical records of participants from three transfusion institutions were collected and analysed. A total of 1027 were enrolled in the cohort; 906 (88.2%) and 121 (11.8%) patients with SCD and thalassemia, respectively. There were 483 (47%) males and 544 (53%) females with median age of 15 (range 1-48). Among the studied population, 78 were alloimmunised with an overall alloimmunisation rate of 7.6%. These patients developed a total of 108 alloantibodies, and anti-E was the most detected antibody (25.9%) followed by anti-K (24.1%). The overall rate of alloimmunisation to RBC antigen among the studied population in Jazan was low compared to other areas in the country. Most alloantibodies detected were against E and K antigens. The knowledge of most encountered alloantibodies in our population will aid in selecting the most appropriate antigen-negative red cells. Further research, however, is needed to explore factors associated with residual risk of alloimmunisation in these patients.

#738 Blood type mismatch between donor and recipient is a risk factor for BK viremia one year after kidney transplantation

Abstract Background and Aims Kidney transplanted recipients are at increased risk of infections, including BK virus, for which there is no specific treatment. Current prevention strategies include surveillance and risk stratification. We sought to estimate the contribution of non-identical but compatible (mismatched) ABO blood types to the risk of BKV viremia. Method A retrospective single-center study was conducted in kidney transplant recipients between 1/1/2011 and 1/12/2021. The primary outcome was viremia (&amp;gt;10,000 copies per ml in two consecutive measurements at least one week apart) during the first year following transplantation. The secondary outcome was the time to BK viremia. We created a multivariate model using stepwise forward regression to assess the risk of viremia. Results During the study period, there were 1244 transplantations, with 1084 performed between donors and recipients with identical blood types (BT). Grafts were received from a living donor in 787 (63.3%) cases, 158 (98.8%) of which were in the mismatched BT group, and 629 (58%) were in the control group. There were 78 episodes of significant BK viremia within the first year post-transplantation, with 60 (5.5%) occurring in the matched BT recipients and 18 (11.3%) in the mismatched BT group (OR 2.16, p = 0.006). Among grafts from living donors during the first year following transplantation, there were 47 (6%) cases of viremia, with 29 (4.6%) in the matched BT group and 18 (11.4%) in the mismatched BT group (OR 2.22, p = 0.001). Multivariate analysis showed that the risk of BKV viremia in the living donor group increased in the presence of mismatched BT (OR = 2.75, p = 0.002). Conclusion The association between donor and recipient BT mismatch and BKV viremia was demonstrated for the first time. Mismatched BT recipients experienced higher rates of BKV viremia compared to identical BT recipients. This might be a preventable risk factor that should guide clinicians in organ procurement.

Challenges in blood transfusion caused by anti-Hr0: A rare case of D-- Phenotype in Asia Abstract

Introduction D–Phenotype is linked to abnormal expression of RHCE gene. Consequently, individuals with this condition may develop antibodies against high-prevalence Rh antigens when exposed to a normal Rh phenotype, leading to challenges in blood matching.Case presentationA 90-year-old male was admitted to the hospital due to prostatitis and acute retention of urinary. Surgery was planned after evaluation by urologist. A request was made for 2 units of red blood cells (RBC). The result for unexpected antibody screening was positive, and the antibody was identified as anti-Hr0 alloantibody , a rare RHCE * CE-D (5) – CE was discovered by genetic testing. The patient has only one history of blood transfusion, which may result in the production of the anti-Hr0 antibody. Compatible blood donors for this patient were not found, even after extensive screening.ConclusionThis report records a rare case of a D-- phenotype individual who produced anti-Hr0 alloantibody. Subsequent analysis of RH gene sequencing revealed a genotype that has not been previously reported in Asia.

How do transfusion services manage patients taking therapies such as anti-CD38 and anti-CD47 known to interfere with red blood cell compatibility testing?

Drugs such as daratumumab (Darzalex, anti-CD38) and Hu5F9-G4 (magrolimab, anti-CD47) may interfere with red blood cell compatibility testing as CD38 and CD47 are expressed on red blood cells. A survey of AABB member transfusion services was undertaken to understand their experiences of managing patients taking therapeutic monoclonal antibodies that are known to interfere with blood grouping and compatibility testing. The survey was distributed to the contact person at US-based AABB member transfusion services. The response rate was 27%. 172 of 240 (72%) indicated they had difficulties in performing compatibility testing in patients taking daratumumab and 66 of 91 (73%) reported difficulties in performing compatibility testing in patients taking magrolimab. Actions taken to provide compatible blood for these patients included referral of all samples to a reference center, blood group pheno/genotyping the patient in advance of starting the drug, treating reagent cells with 0.2 M dithiothreitol and using K-negative red cell units for patients taking daratumumab, and Gamma-clone (Immucor) anti-IgG for indirect antiglobulin testing for patients taking magrolimab. Lack of communication from clinical services about drug treatment was identified as a concern. The results of the survey demonstrate that transfusion services are having challenges with the transfusion management of patients taking therapeutic monoclonal antibodies, and further education is needed.

Pre-transfusion compatibility tests in Malagasy sickle cell patients

Introduction: Blood transfusion is a key component of sickle cell disease management. However, iterative transfusions of labile blood products for sickle cell patients increase the risk of anti-erythrocyte alloimmunization. It is usual to perform pre-transfusion compatibility tests in order to check ABO compatibility and to detect the possible existence of irregular antibodies in patients against the donor's antigens. Methods: This is a prospective and descriptive study dealing with pre-transfusion compatibility tests over a 3-month period, from September 2018 to November 2018, at the Regional Blood Transfusion Centre (CRTS) of Analamanga Region, the capital of Madagascar. Results: We included 33 out of 113 patients during the study period. Compatibility test was positive in 21.21%, of all tested samples. Major and minor compatibility tests were positive alone respectively in 6.25% and 12.50%. And both were positive in 3.12%. The self-test was positive in 3.03% with a positive direct antiglobulin test. Positive compatibility tests were more frequent in patients who received more than two transfusions. Compatible blood bag for the patient was found after testing 2 donor pockets in 27.27% of cases, and after testing 3 pockets in 3.03%. Conclusion: Pre-transfusion compatibility tests are essential and have to be performed systematically on each blood bag before any transfusion. They are used to identify the presence of alloantibodies and provide compatible blood products to patients.

Management of Hyperparasitaemia in Severe Malaria: A Sea Change With the Availability of Artesunate.

This study aims to study the efficacy of exchange transfusion in complicated malaria with hyperparasitaemia. This is a retrospective case-control study conducted in a tertiary care referral hospital in northeastern India. A retrospective chart review was done, and 34 children with hyperparasitaemia were identified. Of these, 16 children received only antimalarial chemotherapy, and 18 received adjunct exchange blood transfusion (EBT). The data was analyzed for survival benefit as the main outcome measure. The subjects in each of the groups were comparable in terms of age, sex distribution, and mean haemoglobin at presentation. The patients treated with EBT were more ill than those who did not receive EBT; they met a greater number of WHO criteria for severe malaria (2.94 ± 1.16 vs. 1.81 ± 0.83; p=0.002) and had higher levels of parasitaemia (23.96 ± 17.55 vs. 16.14 ± 6.89; p=0.0007). The mean volume exchanged was 44.88 ± 20.49 ml/kg, against a target of 70 ml/kg due to the unavailability of fresh, compatible whole blood. There was no difference in mortality in the exchange transfusion group compared to the chemotherapy alone group (22.22% vs. 31.25%; p=0.83). In resource-limited areas, lower volumes of fresh whole blood for exchange transfusion can reduce hyperparasitaemia to a significant degree, and this may give some mortality benefit in very sick cases. Artesunate, by virtue of its rapid action, is capable of reducing hyperparasitaemia and may question the very place of blood transfusion in complicated malaria. It may also be worthwhile to accumulate more data comparing EBT against artesunate instead of quinine.

Transfusing children with sickle cell disease using blood group genotyping when the pool of Black donors is limited.

Red blood cell transfusion is an effective treatment for patients with sickle cell disease (SCD). Alloimmunization can occur after a single transfusion, limiting further usage of blood transfusion. It is recommended to match for the ABO, D, C, E, and K antigens to reduce risks of alloimmunization. However, availability of compatible blood units can be challenging for blood providers with a limited number of Black donors. A prospective cohort of 205 pediatric patients with SCD was genotyped for the RH and FY genes. Transfusion and alloimmunization history were collected. Our capacity to find RhCE-matched donors was evaluated using a database of genotyped donors. Nearly 9.8% of patients carried a partial D variant and 5.9% were D-. Only 45.9% of RHCE alleles were normal, with the majority of variants affecting the RH5 (e) antigen. We found an alloimmunization prevalence of 20.7% and a Rh alloimmunization prevalence of 7.1%. Since Black donors represented only 1.40% of all blood donors in our province, D- Caucasian donors were mostly used to provide phenotype matched products. Compatible blood for patients with rare Rh variants was found only in Black donors. A donor with compatible RhCE could be identified for all patients. Although Rh-compatible donors were identified, blood units might not be available when needed and/or the extended phenotype or ABO group might not match the patient. A greater effort has to be made for the recruitment of Black donors to accommodate patients with SCD.

Discrepancy in ABO Blood Grouping: A Report of B Subgroup with Cold Alloantibody

The ABO antigens are the most important in both blood transfusion and transplantation as their antibody can cause severe haemolytic transfusion reaction when ABO-incompatible transfusion occurs. It has been claimed that variants of the ABO blood group are very rare, including B subgroups. We reported a young healthy female with B subgroup and underlying cold-reacting alloantibody causing challenges in determining of her ABO blood group. Initial ABO blood grouping was misinterpreted as group O. Presence of alloantibody in her plasma was suspected after revealing positive antibody screening. Repeated blood grouping at 37oC revealed a discrepancy of the forward and reverse grouping, which suggested B subgroup. Cross-matching showed difficulties in finding compatible blood with both group O and B cells due to the presence of clinically significant cold alloantibody. Determining of correct ABO blood group is mandatory in transfusion practices as haemolytic transfusion reaction can be prevented.

Phenotyping of Rh and Kell blood group antigen in thalassemia and its impact on alloimmunization in a tertiary care hospital

Objectives: Alloimmunization to red cell antigens is a dreaded complication in multitransfused patients, leading to difficulty in obtaining compatible red blood cell units and development of delayed hemolytic transfusion reactions. The objective of this study was to assess the impact of partial matched phenotype blood (for RhD, C, c, E, e, and Kell antigens) on alloimmunization in thalassemics versus non-phenotype matched blood (ABO &amp; RhD). Materials and Methods: This cross-sectional study was conducted over a period of two years where 250 patients with thalassemias were enrolled. They were divided into two groups, patients in Group I (n = 180) who received partial matched phenotype blood since initiation of transfusion therapy and those in Group II (n = 70) subjects who received usual matched blood. Statistical analysis: All statistical calculations were done using statistical package for the social sciences (SPSS) 21 version. Data were described in terms of range, median (interquartile range [IQR]), frequencies, etc. Results: The median (IQR) age of the study population was 12 (7–18) years (range 6 months–36 years). The most common Rh antibodies were anti-D (2.85%), anti-E (2.85%), anti-C (1.42%), and anti-c (1.42%), and Kell antibodies were (7.1%). It was seen that chances of developing autoantibodies (37% vs. 5%), alloantibodies 11 (15.7% vs. 0%), and transfusion reactions 25 (35.7% vs. 3.3%) were more in Group II subjects as compared to Group I. A significant difference was seen with febrile non-hemolytic transfusion reactions in between two groups 0.001 (95% confidence interval 2.98–65.73). Conclusions: Patients with thalassemia should be typed for RhD (C, c, E, and e) and Kell antigen before initiation of transfusion, which will help in reducing the rate of alloimmunization, autoimmunization, and frequency of transfusion and will improve the overall survival rate in thalassemia.

Rare combination of alloantibodies causing hemolytic disease of the newborn – Challenge for identification

Abstract Hemolytic disease of the newborn (HDN) refers to the destruction of the fetal and newborn red cells by maternal red cell antibodies specific for paternally inherited antigens on fetal red cells or erythroid precursors.[1] ABO-incompatibility is the most common cause of HDN. Rh-negative mothers can be alloimmunized with Rh-positive fetus. Prophylactic Rh immunoglobulin use has greatly reduced the HDN due to Rh incompatibility. Alloimmunization can also occur due to other clinically significant minor blood group antigens such as E, c, C, k, KP(a), Js(a), Js(b), Jk(a), Jk(b), Fy(a), Fy(b), S, s, and U. Multiple alloantibodies in mothers’ blood can pose a difficult challenge for identification and finding compatible blood for exchange transfusion. We report a case of HDN due to multiple antibodies and a rare combination of anti-c and anti-Jkb, challenges associated with the identification, confirmation, and finding of compatible blood units.

Analysis of risk factors for red blood cell alloimmunization and its incidence in hemoglobinopathy patients at a tertiary care center in Odisha, Eastern India

Abstract BACKGROUND: Sickle cell disease (SCD) and thalassemia are common hemoglobinopathies in Eastern India. Regular blood transfusion in these patients leads to alloimmunization. Finding compatible red blood cell units remain a challenge in these patients delaying the transfusion support. AIMS: This study aims to estimate the frequency of alloimmunization and predicts the associated risk factors. METHODOLOGY: A retrospective study was conducted for 2 years. Data were retrieved from the immunohematology work-up record. The Chi-square statistics determined the risk factors associated with alloimmunization. Multivariate regression analysis was used to identify independent risk factors of alloimmunization, adjusting the confounders. A P &lt; 0.05 was considered as statistically significant. RESULTS: Forty-seven patients out of 132 developed antibodies. Of these, 41 presented with only alloantibodies, three patients had only autoantibodies, and the rest 3 had both autoantibodies and alloantibodies. Most commonly observed alloantibodies were against Rh, Kidd, Duffy, and S antigens. SCD appeared a significant risk factor for the development of alloimmunization in the Chi-square test (P = 0.003). However, multivariate analysis revealed only age of more than 2 years at the first transfusion, and up to ten transfusions are independent risk factors of alloimmunization (P &lt; 0.05). CONCLUSION: We found a high incidence of alloimmunization in multitransfused hemoglobinopathies patients in this region. This study also shows the first transfusion at an age of more than 2 years and up to 10 transfusions are independent predictors of alloimmunization.

Phenotypic Frequency of Clinically Significant Blood Group Antigens (Rh, Kell, Kidd, and Duffy) in Blood Donors of the Blood Center at a Tertiary Care Referral Teaching Hospital in Tirupati, Andhra Pradesh, South India

ABSTRACT Background and Objectives: The knowledge of various blood group antigen and phenotype frequencies in a population is important in selecting compatible blood in alloimmunized patients. Such information in Indian population is very limited. Hence this study was carried out to determine the frequency of clinically significant antigens. Such information in Indian population is very limited. Methods: This study was carried out to determine the frequencies of the D, C, c, E, e, K, k, Fya, Fyb, Jka, and Jkb antigens in 1024 blood donors at our department. Samples were collected for extended antigen typing during March 2016–February 2017 for D, C, c, E, e, K, k, Fya, Fyb, Jka, and Jkb antigens using monoclonal antisera by column agglutination technology. Antigenic and phenotypic frequencies were expressed as percentages. Results: Among the Rh system, “e” antigen was found in 98.6% of donors, followed by D (92%), C (89%), c (56%), and E (17%) with DCe/DCe (R1 R1, 41.4%) as the most common phenotype. “k” was found to be positive in 97% of donors, and K+k− phenotype was found in 0.1% of donors. For Kidd and Duffy blood group system, Jk(a+b+) and Fy(a+b+) were the most common phenotypes with frequency of 56.2% and 47.5%, respectively. MNS antigens were not included on account of financial constraints. Conclusion: Database for antigen frequency of various blood group systems in native donors helps provide antigen-negative compatible blood units to patients with multiple antibodies in order to formulate in-house red cells for antibody detection and identification and for preparing donor registry for rare blood groups.

Delayed Graft Function in Pediatric Kidney Transplant: Risk Factors and Outcomes.

We aimed to identify risk factors and outcomes of delayed graft function in pediatric kidney transplant. This retrospective study included all kidney transplant recipients ≤19 years old followed up in our department for a period of 34 years, from January 1989 to December 2022. We included 113 kidney transplant recipients. Delayed graft function occurred in 17 cases (15%). Posttransplant red blood cell transfusion was strongly associated with delayed graft function (adjusted odds ratio = 23.91; 95% CI, 2.889-197.915). Use of allografts with multiple arteries and cold ischemia time >20 hours were risk factors for delayed graft function (adjusted odds ratio = 52.51 and 49.4; 95% CI, 2.576-1070.407 and 1.833-1334.204, respectively). Sex-matched transplants and living donors were protective factors for delayed graft function (adjusted odds ratio = 0.043 and 0.027; 95% CI, 0.005-0.344 and 0.003-0.247, respectively). Total HLA mismatches <3 played a protective role for delayed graft function (adjusted odds ratio = 0.114; 95% CI, 0.020-0.662), whereas transplant within compatible but different blood types increased the risk of delayed graft function (adjusted odds ratio = 20.54; 95% CI, 1.960- 215.263). No significant correlation was shown between delayed graft function and allograft survival (P = .190). Our study suggested delayed graft function as a key factor in allograft rejection-free survival (adjusted odds ratio = 3.832; 95% CI, 1.186-12.377). Delayed graft function was a negative factor for early graft function; patients with delayed graft function had a lower estimated glomerular filtration rate at discharge (P = .024) and at 3 (P = .034), 6 (P = .019), and 12 months (P = .011) posttransplant. Delayed graft function is a major determinant of early graft function and allograft rejection-free survival. Further research is required to establish proper preventive measures.