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Background and Objectives: The anti-A and anti-B are naturally occurring antibodies in the human body but alloantibodies may be formed in individuals who lacks that corresponding red cell antigen after any sensitising event like blood transfusion or pregnancy. The aim of this study was to find the incidence of evanescenct RBC alloantibodies that may not be detectable at the time of pre-transfusion screening. Methods: This was a retrospective observational study from January 2017 to May 2019 in a tertiary care centre from North India. The data on antibody screening and identification retrieved from the departmental records. The patients were screened for red blood cell antibody and those with a positive screening test were further investigated for antibody identification. Antibody screening was performed by solid phase method using Immucor Capture-R Ready Screen (4 cell). Confirmed positive samples were investigated with advance methods of Antibody ID using Reagent panel Red Blood Cells Capture-R Ready ID (16 Cell) in Automated Analyzer Iris or Neo (Immucor Inc. Nocross, GA, USA). As and when required other advance techniques of adsorption and elution, etc were also performed too. Results: The total number of patient screened during this period were 8071. Amongst them 312 were positive for antibody screening (3.8%), of those 216 (62.9%) cases had alloantibodies and 96 (30.7%) cases had autoantibodies. Among the 216 cases of alloantibody, 147 (68.1%) cases had single alloantibody and 69 (31.9%) cases had multiple alloantibodies. Amongst the patients having single alloantibody, the prevalence was highest for Anti-D 54 (36.7%), followed by Anti-E 27 (18.3%), Anti-C 8 (5.4%), Anti-c 7 (4.7%), Anti-K 9 (6.1%), Anti-Fyb 11 (7.4%), Anti-M 18 (12.2%), Anti-N 4 (2.7%), Anti-Fyb 3 (2%), Anti-Lea 3 (2%), Anti-Cw 2 (1.3%) and Anti-Mia 1 (0.6%). Of the 96 patients with autoantibody 72 had warm autoantibody, 10 had cold autoantibody and there were 8 cases of mixed warm and cold autoantibodies. There were 6 patients with warm autoantibody with underlying alloantibody. Conclusion: In conclusion, the high prevalence of Anti-Rh (Anti-D, E), Anti-M, Anti-Fyb antibodies in patient requiring transfusion reiterates the importance of stringent antibody screening and identification as an essential step in preventing delayed hemolytic transfusion reaction. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: A number of glycophorin variant phenotypes or hybrid glycophorin variants of the MNS blood group system bear multiple immunogenic antigens such as Mia, Mur, and MUT. In the East and Southeast Asian populations, glycoprotein (GP.) Mur is the most common glycophorin variant phenotype expressing those three immunogens. The aim of this study was to detect MNS system glycophorin variant phenotypes (GP. Mur, GP. Hop, GP. Bun, GP. HF, and GP. Hut) among Malaysian blood donors. MATERIALS AND METHODS: In this cross-sectional study, 144 blood donors were selected under stratified random sampling. The deoxyribonucleic acid was extracted from whole blood samples, followed by a polymerase chain reaction assay. Sanger sequencing was used to identify the specific MNS variants and then validated by a serological crossmatch with known anti-Mur and anti-MUT. RESULTS: GP. Mur was identified among Malaysian blood donors with a prevalence of 6.94%, and no other variants of the MNS system were found. CONCLUSION: The present study substantiates that GP. Mur is the main variant of the MNS system glycophorin (B-A-B) hybrid in Malaysian blood donors. GP. Mur-negative red blood cells must therefore be considered in the current transfusion policy in order to prevent alloimmunization and immune-mediated transfusion reactions, particularly in transfusion-dependent patients. [ABSTRACT FROM AUTHOR]

BACKGROUND: Multiple reports are available from different parts of the globe indicating the incidences of alloimmunization and blood transfusion-related reactions, which emphasizes the need for phenotyping and providing antigen-matched safe blood. AIMS AND OBJECTIVES: This study aims to determine the frequency of Rh and Kell antigens and phenotype for both donors and patients to propose the importance of providing Rh Kell phenotype cross-matched packed red blood cell (RBC) units to minimize the alloimmunization and transfusion reactions. MATERIALS AND METHODS: Ten thousand blood donors and four thousand patients were investigated between October 2017 and July 2019. Each donor unit was tested for blood grouping, antibody screening, and Rh Kell antigen Phenotyping, and the blood unit was issued after the patient's blood grouping, antibody screening by 3 cell panels, and Rh Kell antigen phenotyping followed by cross-matching with an Rh Kell-matched phenotype RBC unit. RESULTS: Nine thousand four hundred and fifty-two donors were D positive (94.5%) while 548 tested D negative (5.5%). Overall Rh and K antigens frequencies in donors were: "e" (98%) >"D" (94.5%) >"C" (86.6%) > "c" (57.5%) >"E" (18.8%) >K (0.98%). Among patients, 3762 tested D positive (94.05%), and 238 tested D negative (5.95%). Overall Rh and K antigens frequencies in patients were: "e" (98.5%) >"D" (94.05%) >"C" (90.2%) >"c" (51%) >"E" (18.2%) >K (1.8%). CONCLUSION: Our study has given us more clarity on the prevalence of major Rh and K antigens in our donor as well as patient populations, highlighting the similarities as well as differences. This variance holds a great significance, since such donor units when transfused into patients may lead to alloimmunization and adverse transfusion reactions. Hence, the determination of Rh and Kell phenotypes and providing phenotype-matched blood will help prevent such events. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Autoimmune hemolytic anemia is characterized by increased red cell destruction and/or decreased red cell survival due to autoantibodies directed against self-antigens on red cells. Since autoantibodies react with self and nonself red blood cells (RBCs), they tend to mask the underlying clinically significant alloantibodies and many a times mimic a specific pattern like alloantibodies. MATERIALS AND METHODS: We discuss three immune hematological cases of warm autoantibodies. Antibody screening was performed by solid-phase red cell adherence (SPRCA) technique on a fully automated platform NEO Iris (Immucor Inc., USA). In case of a positive antibody screen, antibody identification was performed using SPRCA, NEO Iris (Immucor Inc., USA). Alloadsorption for adsorbing the autoantibodies was done using in-house prepared allogenic packed RBCs – R1R1, R2R2, and rr. RESULTS: All cases had warm autoantibody with a broad specificity against self-Rh antigens. Anti "C" and Anti "e" antibodies were identified in case 1 and autoanti "e" antibody in cases 2 and 3. Case 3 had underlying alloanti "E" along with autoanti "e" which posed a transfusion challenge. CONCLUSION: Our case series highlights the importance of detecting the nature of the antibody whether it is alloantibody or autoantibody with antigen specificity. This would help in selecting appropriate antigen negative blood units for transfusion purpose. [ABSTRACT FROM AUTHOR]

CONTEXT: Alloimmunization by foreign red cell antigens is a matter of concern as it may lead to hemolysis in transfused patients as well as fetus of pregnant females. AIMS: This study aimed to perform a comparative analysis of prevalence and type of irregular antibodies in healthy donors, vis-a-vis blood transfusion recipients. SETTINGS AND DESIGN: Blood samples of 4000 individuals comprising healthy donors, exposed patients, and nonexposed patients were collected and were analyzed for irregular antibodies. MATERIALS AND METHODS: Commercially available three-cell antigen panel was used for the antibody screening. The samples positive in antibody screen were further subjected to an extended 11-cell panel for antibody identification in low-ionic strength saline with and without enzyme. STATISTICAL ANALYSIS: Statistical analysis was done using SPSS for Windows 15.0 program. Chi-square test was used for detecting statistical significance of exposure to red blood cell antigens in the formation of alloantibodies. RESULTS: Of the 4000 samples, antibodies were identified in 105 (2.6%) samples. Overall, nonexposed group showed a seropositivity of 0.36%, while the exposed group showed a seropositivity of 9.4%. Anti-D was the most common antibody found in 38 patients (33.3%). Anti-E was the most common antibody in males, while anti-D was the most common antibody in females. CONCLUSIONS: Since the risk of alloimmunization is more common in multitransfused patients, it is advisable to screen at least those cases for irregular antibodies. [ABSTRACT FROM AUTHOR]