ABSTRACT
Background: The ABO and Rhesus (Rh) blood group system are proved to be useful for blood transfusion purposes. They are also useful for organ transplantation, genetic research, and anthropology. The frequency and distribution of ABO and Rh blood group vary in different populations throughout the world. The knowledge of blood group distribution in respective city or region plays crucial role in the management of blood bank and transfusion services in those areas. Aim and Objectives: The present study was conducted to determine the frequency and distribution of ABO and Rh blood groups in blood donors of tertiary health care center. Materials and Methods: This study was conducted in tertiary care hospital-attached blood bank among the blood donors, who donated blood during the period from January 2017 to December 2021. ABO and Rh blood grouping of these donors were performed by tube agglutination method. Results: Out of 14,409 blood donors, 8,138 (56.5%) were male donors and 6,271 (43.5%) were female donors. The most frequent blood group was O (41.4%) and least common was AB (5.1%). The 95.7% blood donors were Rh positive and 4.3% were Rh negative. Conclusion: In the ABO blood group system, “O” blood group was most common and AB blood group was least common and in Rh blood group system, the Rh positive blood group was more common.
ABSTRACT
Background & objectives: In multitransfused thalassaemic patients, haemagglutination fails to phenotype the patient's blood group antigens due to the presence of donor-derived erythrocytes. DNA-based methods can overcome the limitations of haemagglutination and can be used to determine the correct antigen profile of these patients. This will facilitate the procurement of antigen-matched blood for transfusion to multitransfused patients. Thus, the aim of this study was to compare the serological phenotyping of common and clinically important antigens of Rh, Duffy, Kell, Kidd and MNS blood group systems with molecular genotyping amongst multitransfused thalassaemic patients. Methods: Blood samples from 200 patients with thalassaemia and 100 'O' group regular blood donors were tested using standard serological techniques and polymerase chain reaction-based methods for common antigens/alleles (C, c, D, E, e, Fya, Fyb, Jka, Jkb, K, k, M, N, S, s). Results: Genotyping and phenotyping results were discordant in 77 per cent of thalassaemic patients for five pairs of antithetical antigens of Rh, Duffy, Kell and Kidd blood group systems. In the MNS blood group system, 59.1 per cent of patients showed discrepancy. The rate of alloimmunization among thalassaemics was 7.5 per cent. Interpretation & conclusions: Molecular genotyping enabled the determination of the actual antigen profile in multitransfused thalassaemia patients. This would help reduce the problem of alloimmunization in such patients and would also aid in the better management of transfusion therapy.
ABSTRACT
A determinação do perfil de antígenos eritrocitários em doadores de sangue e pacientes que recebem transfusão sanguínea é importante na prevenção de aloimunização. Pacientes recentemente transfundidos ou com anemia hemolítica autoimune nem sempre conseguem ser fenotipados, e para estes casos a genotipagem vem se apresentando como uma ferramenta auxiliar na tipagem sanguínea. Neste estudo foram padronizadas técnicas de PCR alelo específicas ou de PCR-RFLP para a genotipagem dos alelos de grupos sanguíneos Rh (RHD, RHCE*C/c, RHCE*E/e), Kell (KEL*1/KEL*2), Kidd (JK*A/JK*B) e Duffy (FY*A/FY*B e FY*B(-33T>C)), importantes na medicina transfusional. Elas foram empregadas com sucesso para a tipagem de 36 pacientes que não puderam ser fenotipados ou que apresentaram resultados inconclusivos na fenotipagem eritrocitária. Vinte destes pacientes eram aloimunizados por diferentes antígenos, sendo o anticorpo anti-E o mais frequente (55 por cento). O uso da genotipagem também mostrou-se útil na identificação de anticorpos irregulares. Por sua precisão, facilidade de execução e viabilidade de custo, as técnicas para tipagem de DNA para estes sistemas sanguíneos foram implantadas em nosso Serviço a partir de 2007 e vêm sendo usadas na prática transfusional, contribuindo para aumento da segurança dos pacientes cronicamente transfundidos ou com anemia hemolítica autoimune, como, por exemplo, pacientes com anemia falciforme. Além disso, ela vem permitindo o melhor uso de unidades de sangue com fenótipos menos frequentes na nossa população de doadores de sangue.
The determination of the blood group antigen profile of blood donors and transfusion patients is important to avoid alloimmunization. The knowledge of blood group polymorphisms acquired over the last few years has permitted the development of molecular methods that are able to predict blood group phenotypes. For patients who have recently been transfused or those who present with autoimmune hemolytic anemia, genotyping is an important tool in blood typing. We used molecular biology (allele-specific PCR and PCR-RFLP) to genotype Rh (RHD, RHCE*C/c, RHCE*E/e), Kell (KEL*1/KEL*2), Kidd (JK*A/JK*B) and Duffy (FY*A/FY*B and FYB(-33T>C)) alleles and solved the inconclusive blood types of 36 patients. Twenty patients had developed irregular antibodies of different red blood cell antigens, most frequently anti-E (55 percent). The definition of irregular antibodies was feasible by genotyping. Due to their accuracy, simplicity and economic viability, these tests have been used in the clinical practice in our Institution since 2007, contributing to the management of chronically transfused patients. Additionally, these tests allow a better use of less common blood units related to the ethnicity of the blood donor population.
Subject(s)
Humans , Blood Group Antigens/analysis , Blood Transfusion , Genotype , Rh Isoimmunization , Rh-Hr Blood-Group SystemABSTRACT
Os antígenos de grupos sanguíneos eritrocitários são estruturas macromoleculares localizadas na superfície extracelular da membrana eritrocitária. Com o desenvolvimento de estudos moleculares, mais de 250 antígenos são conhecidos e estão organizados em 29 sistemas de grupos sanguíneos reconhecidos pela Sociedade Internacional de Transfusão Sanguínea (ISBT). Estudos têm revelado que os antígenos de grupo sanguíneo estão expressos na membrana eritrocitária com ampla diversidade estrutural, incluindo epítopos de carboidratos em glicoproteínas e/ou glicolipídios e em proteínas inseridas na membrana via um domínio, via domínios de multipassagem ou ligados a glicosilfosfatidinositol. Além das diversidades estruturais, muitas funções importantes têm sido associadas aos antígenos eritrocitários recentemente identificadas, podendo ser esquematicamente divididas em: estruturais, transportadores, receptores e moléculas de adesão, enzimas, proteínas controladoras do complemento e outras. Esta revisão tem como foco as funções potenciais das moléculas que expressam os antígenos eritrocitários.
Erythrocyte blood group antigens are macromolecules structures located on the extracellular surface of the red blood cell membrane. The development of molecular studies allowed the recognition of more than 250 antigens by the International Society for Blood Transfusion (ISBT). These studies have also shown that blood group antigens are carried on red blood cell membrane of wide structural diversity, including carbohydrate epitopes on glycoproteins and/or glycolipids and on proteins inserted within the membrane via single or multi-pass transmembrane domains, or via glycosylphosphatidylinositol linkages. In addition, to their structural diversity, many important functions associated with blood group antigens have been recently identified and can be didactically divided into: structural proteins, transporters, receptors and adhesion molecules, enzymes, complement control proteins and others. This review will focus on the potential functions of the molecules that express blood group antigens.