Análise do perfil de Rh e Kell em doadores de sangue em Porto Alegre, Rio Grande do Sul / Phenotypic profile analysis of Rh and Kell blood group systems among donors in Porto Alegre, Rio Grande do Sul

Introdução: A hemoterapia é uma prática terapêutica pelo meio de transfusão sanguínea. Devido ao baixo estoque de bolsas de sangue e o aumento de pacientes crônicos e emergenciais, se faz necessária a realização de testes imuno-hematológicos para minimizar os riscos de reações transfusionais e aloimunizações em doadores e receptores de sangue. Deste modo, no estudo foi avaliada a prevalência dos antígenos dos sistemas Rh e Kell em doadores de sangue de Porto Alegre ­ RS.Métodos: Estudo quantitativo, transversal e retrospectivo que foi realizado através da análise das informações dos doadores de sangue contidas no banco de dados do Hemocentro do Estado do Rio Grande do Sul, nos anos de 2018 e 2019.Resultados: Das 6.479 amostras fenotipadas, quanto ao sistema Rh, 44,6% são Rh positivo e 55,4% são Rh negativo. As frequências dos antígenos encontradas foram de, CC 10,1%, Cc 27%, cc 62,9%, EE 1,2%, Ee 13,9%, ee 84,9%. E, para o sistema Kell, K1 positivo 7,1% e K1 negativo 92,9%.Conclusões: Antígenos do sistema Rh e Kell exibem um grande nível de imunogenicidade e uma forte ligação com a Doença Hemolítica do Recém-nascido, podendo ocorrer a sensibilização em pacientes caso não haja a compatibilidade sanguínea. Este estudo ressalta a importância da implementação da fenotipagem eritrocitária em doadores de sangue, sugere-se mais estudos com períodos distintos para a pesquisa de resultados satisfatórios.

Introduction: Hemotherapy is a therapeutic practice consisting of blood transfusion. Low blood supply and an increase in chronic and emergency patients have made it necessary to conduct immunohematology tests to minimize the risks of adverse reactions and alloimmunization in donors and recipients. Therefore, this study aimed to assess the prevalence of Rh and Kell blood group antigens among blood donors in Porto Alegre, Rio Grande do Sul, Brazil.Methods: We conducted a quantitative, cross-sectional, retrospective study. Information from blood donors included in the Rio Grande do Sul's Blood Center database from 2018 to 2019 were analyzed.Results: A total of 6,479 samples were phenotyped, of which 44.6% were Rh-positive and 55.4% were Rh-negative. Antigen prevalence was CC (10.1%), Cc (27%), cc (62.9%), EE (1.2%), Ee (13.9%), and ee (84.9%). As for the Kell group, 7.1% were K1-positive and 92.9% were K1-negative.Conclusions: The Rh and Kell antigens are highly immunogenic and have a strong link with the hemolytic disease of the newborn. Sensitization may occur in patients if there is no blood compatibility. This study highlights the importance of implementing erythrocyte phenotyping in blood donors. Further studies should be conducted in different time frames to achieve satisfactory results.

Frequências fenotípicas dos sistemas de grupos sanguíneos ABO, Rh e Kell em doadores de sangue da região metropolitana de Belém-PA / Phenotype frequencies of ABO, Rh and Kell blood group systems in blood donors in the metropolitan region of Belém-PA

Objetivo: O objetivo deste trabalho foi realizar um estudo das frequências dos principais antígenos e fenótipos dos sistemas de grupo sanguíneo: ABO, Rh, Kell. Métodos: A partir dos dados da fenotipagem estendida disponíveis no Sistema de Banco de Sangue (SBS web) de doadores de sangue da Fundação Hemopa, foram avaliadas as frequências absolutas e relativas. Resultados: Dentre os 1.474 doadores analisados houve predominância do tipo O (62,6%) e quanto ao Rh: D (85,5%). O antígeno mais frequente do sistema Rh foi: e (94,9%), e o fenótipo mais frequente: DCcee (27,5%). O antígeno mais frequente do sistema Kell foi: Kpb (100%), e o fenótipo: k+ K- (95,7%), Kp (a- b+) (99,4%). Conclusão: A identificação das frequências desses antígenos em diferentes populações pode auxiliar na rotina hemoterápica, facilitando a busca por hemocomponentes compatíveis, melhorando a segurança transfusional imunológica.

Objective: To study the frequencies of the major antigens of bloodgroup systems:ABO, Rh, Kell. Methods: From data of extendedphenotyping available in the Blood Bank System (SBS web) in blooddonors of the Hemopa Foundation, were evaluated absolute and relativefrequencies. Results: Among the 1.474 donors analyzed there was apredominance of type O (62.6%) and RhD (85.5%). The most frequentantigen from system Rh was: e (94,9%), and the most commonphenotype: DCcee (27,5%). The most frequent antigen from systemKell was: Kpb (100%), and the most common phenotypes: k + K-(95.7%), Kp (a- b +) (99.4%). Conclusion: Identifying the frequenciesof these antigens in different populations may help in the routine bloodtherapy, facilitating the search for compatible blood components,improving the immunological transfusion safety.

Frecuencia y procedencia del antígeno Kell en mujeres donantes de sangre durante los años 2016-2017 / Frequency and origin of the Kell antigen in female blood donors during 2016-2017

Resumen Introducción: El sistema Kell está formado por dos antígenos principales: el Kell (K) y el Cellano (k), estos son capaces de causar reacciones graves, tales como reacción hemolítica postransfusional y la enfermedad hemolítica del recién nacido. Los antígenos de este sistema son altamente inmunogénicos lo que les confiere el tercer lugar en importancia clínica. Objetivo: Determinar la frecuencia del antígeno Kell y procedencia de las mujeres donantes de sangre con antígeno Kell positivo en el Hemocentro del Centro Oriente Colombiano (HCOC). Metodología: Estudio descriptivo de corte transversal que incluyó 186 donantes voluntarias de sangre del Hemocentro Centro Oriente Colombiano, se realizó la fenotipificación del antígeno Kell, utilizando la técnica Aglutinación en lámina, la cual se basa en enfrentar glóbulos rojos del donante con anticuerpo monoclonal anti K. Se calculó la frecuencia fenotípica del antígeno Kell, en porcentajes y para el procesamiento de la información se utilizó el paquete estadístico SPSS versión 21.0 en español donde se realizó todo el análisis de los datos de la población. Resultados: Se procesaron 177 muestras obtenidas en 9 campañas de donación de sangre realizadas en diferentes municipios del departamento de Boyacá, obteniéndose una frecuencia fenotípica del 7,5% para el antígeno Kell, en la población de mujeres donantes de sangre del HCOC, siendo esta similar con la frecuencia encontrada en Colombia y Latinoamérica. Conclusión: Se determinó que la frecuencia del antígeno Kell en las mujeres donantes de sangre del HCOC fue del 7,5%, y se logró identificar que no existe una relación estadísticamente entre la procedencia y la presencia del antígeno Kell en las donantes, lo anterior está relacionado con el mestizaje y los procesos de migración.

Abstract Introduction: The Kell system consists of two major antigens: Kell (K) and Cellano (K), which are capable of causing serious reactions, such as posttransfusion hemolytic reaction and hemolytic disease of the newborn. The antigens of this system are highly immunogenic which gives them the third place in clinical importance. Objective: To determine the frequency of Kell antigen and origin of blood donors in the Hemocenter of the Centro Oriente Colombiano (H.C.O.C). Methods: Cross-sectional descriptive study involving 186 blood donors from the Centro Oriente Colombian Hemocenter, phenotyping of the Kell antigen was carried out, using the technique Aglutination in lamina, which is based on facing donor red blood cells with anti-K monoclonal antibody. Calculated the phenotypic frequency of the Kell antigen in percentages and for the processing of the information was used the statistical package SPSS version 21.0 in Spanish where all the analysis of the data of the population was carried out. Results: 177 samples obtained in 9 blood donation campaigns were carried out in different municipalities of the department of Boyacá, obtaining a phenotypic frequency of 7.5% for the Kell antigen in the population of female HCOC blood donors. Similar to the frequency found in Colombia and Latin America. Conclusion: It was determined that the frequency of Kell antigen in the female HCOC donors was 7.5%, and it was possible to identify that there is no statistically relation between the origin and the presence of Kell antigen in the donors, Is related to mestizaje and migration processes.

Febrile neutropenia following parvovirus B19 infection and cross anti-kell reaction to E. coli in pregnancy / Infeção por parvovírus B19 causando neutropenia febril e reação cruzada anti-Kell com E. coli na gravidez

Abstract Parvovirus B19 has tropism for red line blood cells, causing immune hydrops during pregnancy. A positive anti-Kell Coombs reaction usually happens during pregnancy when there is production of antibodies that target Kell antigens, but cross reactions to other antigens may occur. A 24-year-old Gypsy primigravida, 0 Rhesus positive, presented with persistent isolated hyperthermia for 2 weeks and a positive indirect Coombs test result with anti-Kell antibodies at routine tests. She had a 19-week live fetus. The blood tests revealed bicytopenia with iron deficiency anemia, leucopoenia with neutropenia, and elevated C-reactive protein. She was medicated with imipenem, and had a slow clinical recovery. Blood, urine and sputum samples were taken to perform cultures and to exclude other systemic infections. Escherichia coli was isolated in the urine, which most probably caused a transient cross anti-Kell reaction. Haemophilus influenza in the sputum and seroconversion to parvovirus B19 was confirmed, causing unusual deficits in the white cells, culminating in febrile neutropenia. Despite the patient's lack of compliance to the medical care, both maternal and fetal/neonatal outcomes were good. This a rare case report of 2 rare phenomena, a cross anti-Kell reaction to E. coli and parvovirus B19 infection with tropism for white cells causing febrile neutropenia, both events occurring simultaneously during pregnancy.

Resumo O parvovírus B19 tem tropismo para as células sanguíneas da linha vermelha, causando hidropsia imune durante a gravidez. O teste Coombs anti-Kell positivo ocorre durante a gravidez quando há produção de anticorpos contra os antígenos de Kell, mas pode haver reações cruzadas para outros antígenos. Uma grávida primigesta de etnia cigana, de 24 anos, 0 Rhesus positivo, recorreu ao hospital às 19 semanas de gestação por hipertermia isolada persistente por 2 semanas e umteste Coombs indireto positivo por anticorpos anti-Kell em testes de rotina da gravidez. O estudo analítico revelou bicitopenia com anemia ferropênica, leucopenia com neutropenia, e elevação da proteína C-reativa. A paciente foi medicada com imipenem, e teve uma recuperação clínica lenta. Foram colhidas amostras de sangue, urina e expectoração para culturas bacterianas. Na urina, foi isolada Escherichia coli, o que provavelmente causou a reação anti-Kell cruzada transitória. Na expectoração, foi isolada Haemophilus influenza, e foi confirmada seroconversão para o parvovírus B19, que causou um déficit incomum na linhagem sanguínea branca, culminando com neutropenia febril. Apesar da má adesão aos cuidados médicos, os desfechos materno e fetal/neonatal foram bons. Este é um caso de 2 fenômenos raros, uma reação cruzada anti-Kell à infecção por E. coli, e parvovírus B19 comtropismo para células brancas causando neutropenia febril, ambos ocorrendo simultaneamente durante a gravidez.

A Case of Packed red Cell Transfusion-Associated Anti-K Antibody

Anti-K alloantibody is a type of red blood cell (RBC) antibody which is generated through immunization. It is well noted that the anti-K antibody causes hemolytic transfusion reactions. Although Koreans generally do not have the K antigen on RBCs, we report a rare case of transfusion-related anti-K antibody in Korean patient. Just twelve pints of packed RBCs had been transfused to the patient before the anti-K was identified for the first time, but the donor information about Kell phenotype (K or k) was not available. The anti-K had been continuously detected, and the patient neither received immunoglobulins nor experienced bacterial infections which could generate anti-K antibody. Therefore we believe that her anti-K is the truly positive, previously transfused packed RBCs-related alloantibody. The packed RBCs transfused to our patient were likely to be donated from other races. The pre-transfusion irregular antibody detection test should be performed carefully to detect very rare RBC alloantibodies.

Frequencies of polymorphisms of the Rh, Kell, Kidd, Duffy and Diego systems of Santa Catarina, Southern Brazil

Background Red blood cell genes are highly polymorphic with the distribution of alleles varying between different populations and ethnic groups. The objective of this study was to investigate gene polymorphisms of blood groups in the state of Santa Catarina, Southern Brazil. Methods Three hundred and seventy-three unrelated blood donors and 31 transfusion-dependent patients were evaluated to investigate polymorphisms of the Rh, Kell, Duffy, Kidd, and Diego blood group systems in a population from the state of Santa Catarina. The subjects, from seven regions that comprise the blood-banking network of the state, were assessed between August 2011 and March 2014. The genotypes of the Rh, Kell, Duffy, Kidd, and Diego systems were determined using the restriction fragment length polymorphism-polymerase chain reaction and allele-specific polymerase chain reaction techniques. Results The genotype frequencies in this study were significantly different when populations from different regions of Santa Catarina were compared. Furthermore, there were also significant differences in the genetic frequencies compared to other Brazilian states. The genotype frequencies of the Kell and Kidd blood groups are similar to European populations from Naples, Italy and Zurich, Switzerland. Conclusion This article reports for the first time the frequency of polymorphisms of blood group systems in blood donors from Santa Catarina, Southern Brazil.

Frecuencia de antígenos del sistema sanguíneo Rh y del sistema Kell en donantes de sangre / Frequency of antigens in Rh and Kell blood system in blood donors

Introducción: los estudios inmunohematológicos que se realizan a los donantes de sangre se orientan a proporcionar al receptor una terapia transfusional compatible con el sistema sanguíneo ABO y antígeno D del sistema Rh. Sin embargo, como una forma de incrementar la seguridad transfusional, surge el interés de ampliar la gama de antígenos a determinar y por ende, a compatibilizar previo a una transfusión sanguínea. Objetivo: determinar la frecuencia de los cinco antígenos mayores del sistema Rh y los antígenos K1 y K2 del sistema Kell en donantes voluntarios de sangre. Métodos: Estudio descriptivo transversal que incluyó 200 donantes voluntarios de sangre del Centro Productivo Regional de Sangre del Maule (CPRSM) seleccionados al azar. Se realizó fenotipificación de los cinco antígenos mayores del sistema Rh. y el antígeno K1 y K2 del sistema Kell. Se utilizó la técnica de hemaglutinación en tubo, con sueros monoespecíficos y DG Gel® Coombs. Se calculó la frecuencia fenotípica de los antígenos D, C, c, E y e del sistema Rh., y K1 y K2 del sistema Kell, en porcentajes. A partir de la frecuencia de los fenotipos Rh. se determinó la frecuencia del genotipo más probable de dicho sistema. Para el Kell se estimó el genotipo en base al fenotipo. Resultados: sistema Rh: 96 por ciento de las muestras estudiadas presentaba el antígeno D, 97,5 por ciento el antígeno e; 35,5 por ciento el antígeno E; 79 por ciento el antígeno C y 65,5 por ciento el antígeno c. El genotipo más frecuente fue CDe/CDe. Sistema Kell: se encontró una frecuencia del 4 por ciento para el antígeno K1, mientras que el antígeno K2 presenta una frecuencia del 99,5 por ciento. Al nivel de frecuencia genotípica se detectó que el 96 por ciento de la población tiene un genotipo homocigoto para K2 (kk). Conclusiones: La frecuencias de los siete antígenos estudiados es similar a la descrita en otras poblaciones(AU)

Introduction: Immunologic studies performed on blood donors are directed to provide a transfusion therapy compatible with ABO blood group system and Rh system D antigen in the recipient. However, as a way to increase transfusion safety, the interest of expanding the range of antigens to determine and therefore to be tested for compatibility prior to a blood transfusion, arises. Aim: To determine the frequency of the five major antigens of Rh. system and K1 and K2 antigens of the Kell system in blood donors. Methods: Cross-sectional study including 200 randomly selected voluntary blood donors from Centro Productivo Regional de Sangre del Maule (CPRSM). Phenotyping of five major antigens of Rh. system and K1 and K2 Kell system antigens was carried out. The tube hemagglutination technique with monospecific Coombs sera and DG Gel ® was used. The Rh. system D, C, c, E, e antigens and Kell system K1 and K2 antigen phenotypic frequencies were calculated in percentages. The most likely Rh.genotype was determined from the phenotype frequency of this system. Similarly, in Kell system the genotype frequency was determined based on phenotype. Results: In the Rh.system, 96 percent of the samples studied had D antigen; 97.5 percent had the e antigen, and 35.5 percent the E antigen. Antigen C was present in 79 percent and c in 65.5 percent. The most frequent Rh. genotype was CDe/CDe. In Kell system, K1 antigen presented a frequency of 4 percent, while antigen K2 presented a 99.5 percent. Regarding genotypic frequency, a 96 percent of the population showed a K2 (kk) homozygous genotype(AU) Conclusion: The frequency of the seven antigens studied is similar to that described in other populations(AU)

Premio Dr. Antonio Pérez Prado - XIV Congreso Argentino de Medicina Transfusional. Isoinmunización por anti-K1: manejo clínico e inmunohematológico de 30 casos / Dr. Antonio Pérez prado Award - XIV Argentine Congress of Transfusion Medicine. Anti K1 isoimmunization: clinical and immunohematological management of 30 cases

Introducción: La principal causa de anemia fetal es la inmunización por anticuerpos (Acs.) anti-D. La inmunización por anti-K1 es poco frecuente aunque puede producir un cuadro de anemia fetal muy grave. Su incidencia relativa ha aumentado en los últimos años por el aumento de las transfusiones sanguíneas y por disminución de la inmunización anti-D. Presentamos el seguimiento obstétrico e inmunohematológico de 30 casos de gestantes sensibilizadas por anti-Kl. Objetivo: mostrar nuestra experiencia en el manejo clínico e inmunohematológico de gestantes con anti-Kl. Materiales y métodos: Estudio de 30 gestantes con anti-Kl, controladas entre 2005-2012, sobre un N = 48.550 embarazadas. Se estudiaron: compromiso fetal. necesidad de terapéutica intragestacional y posparto, semanas de gestación en el momento del diagnóstico, estado perinatal y complicaciones de las terapéuticas. Además, ABO-Rh, fenotipo materno Rh/Kell, detección e identificación de Acs, título, score, fenotipo Rh/K paterno, seguimiento con ultrasonido para detectar signos de anemia, y desde 2008 control del Pico Sistólico Máximo en arteria cerebral media (PSM-ACM). Resultados: Del total de madres estudiadas, 30 (0,06%) tenían anti-Kl (solo o con anti-D+C, anti-D o anti-Klpa).Títulos de anti-Kl: entre 8 y 8192. De esas solamente 9 (30%) con antecedentes transfusionales. Todos los fetos nacieron vivos. En la mayoría, la inmunización fue leve, sin repercusión en el feto, salvo cuando asociado con Anti-D (quien requirió 5 transfusiones intraútero -TIU- y gammaglobulina intravenosa -lgIV ­entre semana 14 y 32). Todos los recién nacidos (RN) tuvieron peso y apgar adecuados. Hubieron 2 nacimientos prematuros (36 y 34 sem), 1 por diabetes + hipertensión y el otro con Enfermedad Hemolítica Perinatal (EHP) por anti-D+C. Los PSM-ACM fueron adecuados para cada edad gestacional, y nunca superaron el 1,49 múltiplo de la mediana. excepto en 1 paciente con Anti-D...

Introduction: The main cause of fetal anemia is caused by anti-D antibodies (Abs). Anti-K1 immunization is infrequent but can lead to asevere episode of fetal anemia. Its relative incidence has increased in the last few years due to increasing blood transfusions and diminishing anti-D immunization. We hereby present 30 cases of pregnant women with anti-K1. Objective: To show our experience in handling pregnant women with anti-K1.Materials and methods: Retrospective study of 30 pregnant women with anti-K1, under surveillance in the period 2005-2012, N= 48,550 women. Study outcome measures: fetal condition, peripartum (intravenous glob­ulin [IVlg], intrauterine transfusion [IUT]) therapy. Other measures: gestational age at the moment of diagnostic, perinatal status (abortion, fetal death, regular delivery, C­section or need for induction) and therapy complications. Immunohematology tests: ABO-Rh, maternal Rh/Kell phenotype, Ab screening and identification, titer, score,paternal Rh/K phenotype. In all cases of a mother with anti-K1 and a K+ father, confirmed or suspected, a detailed ultrasound follow-up was carried out to detect signs of ane­mia and, from 2008 onwards, a control of middle cerebral artery peak systolic velocity (MCA-PSV). Immunization was rated as low when no antepartum treatment was necessary, and as severe when such treatment was needed. Results: Out of all the studied women, 30 (0,06%) presented anti-K1 (alone or accompanied by anti-D+C, anti-D or anti-K1 pa). Anti-K1 titers: 8 to 8192. Only 9 (30%) patients informed previous transfusional events. AII fetuses were born alive. ln most pregnancies immunization was low, without any effects on the fetus, except for a case related to Anti-D (requiring 5 IUT and Ivlg between weeks 14 and 32). AII newborns (NB) had adequate weight and apgar readings...

An easy and efficient strategy for KEL genotyping in a multiethnic population

BACKGROUND: The Kell blood group system expresses high and low frequency antigens with the most important in relation to transfusion including the antithetic KEL1 and KEL2; KEL3 and KEL4; KEL6 and KEL7 antigens. Kell is a clinically relevant system, as it is highly immunogenic and anti-KEL antibodies are associated with hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. Although required in some situations, Kell antigen phenotyping is restricted due to technical limitations. In these cases, molecular approaches maybe a solution. This study proposes three polymerase chain reaction genotyping protocols to analyze the single nucleotide polymorphisms responsible for six Kell antithetic antigens expressed in a Brazilian population. METHODS: DNA was extracted from 800 blood donor samples and three polymerase chain reaction-restriction fragment length polymorphism protocols were used to genotype the KEL*1/KEL*2, KEL*3/KEL*4 and KEL*6/KEL*7 alleles. KEL*3/KEL*4 and KEL*6/KEL*7 genotyping was standardized using the NlaIII and MnlI restriction enzymes and validated using sequencing. KEL*1/KEL*2 genotyping was performed using a previously reported assay. RESULTS: KEL genotyping was successfully implemented in the service; the following distribution of KEL alleles was obtained for a population from southeastern Brazil: KEL*1 (2.2%), KEL*2 (97.8%), KEL*3 (0.69%), KEL*4 (99.31%), KEL*6 (2.69%) and KEL*7 (97.31%). Additionally, two individuals with rare genotypes, KEL*1/KEL*1 and KEL*3/KEL*3, were identified. CONCLUSION: KEL allele genotyping using these methods proved to be reliable and applicable to predict Kell antigen expressions in a Brazilian cohort. This easy and efficient strategy can be employed to provide safer transfusions and to help in rare donor screening.

Genotyping for Kidd, Kell, Duffy, Scianna, and RHCE blood group antigens polymorphisms in Jiangsu Chinese Han / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Molecular testing is more precise compared to serology and has been widely used in genotyping blood group antigens. Single nucleotide polymorphisms (SNPs) of blood group antigens can be determined by the polymerase chain reaction with sequence specific priming (PCR-SSP) assay. Commercial high-throughput platforms can be expensive and are not approved in China. The genotype frequencies of Kidd, Kell, Duffy, Scianna, and RhCE blood group antigens in Jiangsu province were unknown. The aim of this study is sought to detect the genotype frequencies of Kidd, Kell, Duffy, Scianna, and RhCE antigens in Jiangsu Chinese Han using molecular methods with laboratory developed tests.</p><p><b>METHODS</b>DNA was extracted from EDTA-anticoagulated blood samples of 146 voluntary blood donors collected randomly within one month. Standard serologic assay for red blood cell antigens were also performed except the Scianna blood group antigens. PCR-SSP was designed to work under one PCR program to identify the following SNPs: JK1/JK2, KEL1/KEL2, FYA/FYB, SC1/SC2, C/c and E/e.</p><p><b>RESULTS</b>Serologic antigen results were identical to the phenotypes that were predicted from genotyping results. The allele frequencies for Jk*01 and Jk*02 were 0.51 and 0.49, respectively; for Fy*A and Fy*B 0.94 and 0.06; for RHCE*C and RHCE*c 0.68 and 0.32; and for RHCE*E and RHCE*e 0.28 and 0.72. Among 146 blood donors, all were KEL*02/KEL*02 and SC*01/SC*01, indicating allele frequencies for KEL*02 and SC*01 close to 1.00.</p><p><b>CONCLUSIONS</b>The use of PCR-SSP working under the same condition for testing multiple antigens at the same time is practical. This approach can be effective and cost-efficient for small-scale laboratories and in developing counties. These molecular tests can be also used for identifying rare blood types.</p>

Genetic polymorphisms of Rh, Kell, Duffy and Kidd systems in a population from the State of Paraná, southern Brazil

BACKGROUND: Red blood group genes are highly polymorphic and the distribution of alleles varies among different populations and ethnic groups. AIM: To evaluate allele polymorphisms of the Rh, Kell, Duffy and Kidd blood group systems in a population of the State of Paraná METHODS: Rh, Kell, Duffy and Kidd blood group polymorphisms were evaluated in 400 unrelated blood or bone marrow donors from the northwestern region of Paraná State between September 2008 and October 2009. The following techniques were used: multiplex-polymerase chain reaction genotyping for the identification of the RHD gene and RHCE*C/c genotype; allele-specific polymerase chain reaction for the RHDΨ and restriction fragment length polymorphism polymerase chain reaction for the RHCE*E/e, KEL, FY-GATA and JK alleles. RESULTS: These techniques enabled the evaluation of the frequencies of Rh, Kell, Duffy and Kidd polymorphisms in the population studied, which were compared to frequencies in two populations from the eastern region of São Paulo State. CONCLUSION: The RHCE*c/c, FY*A/FY*B, GATA-33 T/T, JK*B/JK*B genotypes were more prevalent in the population from Paraná, while RHCE*C/c, FY*B/FY*B, GATA-33 C/C, JK*A/JK*B genotypes were more common in the populations from São Paulo.

Isoinmunización antikell: manejo clínico de 26 casos / Antikell alloinmunization: clinical management of 26 cases

La principal causa de anemia fetal es la isoinmunización Rh por el desarrollo de anticuerpos frente al antí-geno D. La aloinmunización antiKell es una patología poco frecuente aunque puede producir un cuadro de anemia fetal muy grave. Su incidencia relativa ha aumentado en los últimos años debido al mayor número de transfusiones sanguíneas por disminución de la isoinmunización anti-D. Presentamos 26 casos de isoin-munización antiKell controlados en el Hospital La Paz de Madrid, durante los años 2003-2009 y una revisión de la literatura.

The main cause of fetal anemia is red-cell alloimmunization. Kell alloinmunization is a rare disease, although it can produce severe fetal damages. The relative incidence of antiKell isoinmunization has increased last years due to the blood transfusions has grown also, and anti-D aloinmunization has decreased. We report twenty six cases of pregnant women with isoinmunization antikell controlled in La Paz Hospital, Madrid, between 2003-2009 and a review of the literature.

A Hemolytic Transfusion Reaction due to Anti-Ku Antibody in a Patient with Knull Phenotype: The First Case in Korea / 대한진단검사의학회지

Knull phenotype completely lacks all Kell system antigens. Anti-Ku antibody is seen in immunized persons with Knull phenotype by transfusion or pregnancy. It can cause a fatal hemolytic transfusion reaction. A 66-yr-old male patient with liver cirrhosis visited emergency center due to acute bleeding. The patient was at hypovolemic shock status: his blood pressure was 80/50 mmHg, pulse rate was 110/min and hemoglobin level was 4.4 g/dL. Because of the presence of antibody against high incidence antigen, we could not find any compatible blood for the patient. Nevertheless, 4 units of packed RBCs had to be transfused. Moderate hemolytic transfusion reaction was developed after transfusion. At endoscopic examination, blood was spurting from gastric cardiac varix. Endoscopic histoacryl injection was tried, and bleeding was successfully controlled. After bleeding stopped, he was managed for anemia using steroid and other medical therapy instead of transfusion. His hemoglobin level was improved to 7.7 g/dL at the time of discharge. Later he has been proved to have a Knull phenotype, which is very rare, and anti-Ku antibody. This report is the first case of anti-Ku in a Knull phenotype person in Korea, who experienced a moderate hemolytic transfusion reaction.

Different KEL gene mRNA transcripts in reticulocyte and non-reticulocyte cells / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the difference of the transcripts between reticulocyte and non-reticulocyte cells in human blood.</p><p><b>METHODS</b>Genomic DNA, reticulocyte RNA and total RNA of K-, K+ and Kell-null(K0) were extracted, then PCR, reverse transcription-PCR(RT-PCR) and nested PCR followed by sequencing or cloning-sequencing were used to analyze the KEL gene mRNA exons 1-19 and exons 2-8. Four kinds of monoclonal antibodies were labeled to detect the expression of Kell glycoprotein on red cells or leukocytes with flow cytometry.</p><p><b>RESULTS</b>In reticulocyte, only one normal KEL transcript faithful to the genomic structure was found in all tested samples except K0 which had 4 different transcripts. Sequence analysis of exons 2-8 of total RNA confirmed the alternative KEL transcripts existed in different samples, mostly caused by abnormal splicing, among them, skipping of exon 3 and a 16 bp insertion of intron 6 at the beginning of exon 7 were the most frequent. Although only one band was observed after amplifying the exons 1-19 from total RNA, the sequencing result showed it was a mixture of different sequences. There was strong expression of Kell glycoprotein on red cells except K0, but no or low expression on leucocytes by flow cytometry.</p><p><b>CONCLUSION</b>Alternative transcripts of KEL gene exist in different cells, which would be responsible for different Kell glycoprotein expression patterns on different cells. This study suggested that reticulocyte RNA was more suitable than total RNA for molecular study of KEL gene transcription.</p>

Red blood cell alloimmunization among Saudi pregnent women in the central province of Saudi Arabia

To determine the incidence of alloimmunization among pregnant women in Saudi Arabia Prospective study King Khaled University, Hospital, Riyadh, Saudi Arabia One thousand one hundred and ninty five pregnant women The rates of alloimmunization among pregnant women subjects by analyzing the blood type of both mother and neonate The largest fraction of alloimmunization involved Rh antigens [52.38%], while other groups such as Kell and Duffy play a less common role. Alloantibodies identified fivety pesofalloantibodiesin addition to nonspecific-autoantibodies. The most frequent [52.38%] were against Rhesus 2.38%; Kell 2.38%; Duffy 2.38%; 4.76% were non-specificantibodiesand33.3%were autoantibodies. Alloimmunization are: anti-D 28.57%, anti-C 4.76% anti-E 14.28% and anti-e 4.76%; only one 2.38% developed anti-K; anti-Jk, one 2.38%; one had anti-Le 2.38%; there was one 2.38% with anti-Fy. 1.84% of the total number of study subjects were alloimmunized by antigens of Rh while 0.08% were alloimmunized to antigens either from Kell, Kidd, Lewis or Dufffy. The relative importance of antigens other than Rh D have increased since the introduction of Rh D prophylactic treatment. Alloimmunization to E, c and Kell antigens can reach significantproportionsofstudied populations and can result in deleterious effects on fetus. The actual risk of alloantibody production during pregnancy is unknown but stimuli for antibody production are feto-maternal bleeds that occur throughout pregnancy

A Rare Case of Transfusion-related Anti-K Alloantibodies / 대한수혈학회지

No abstract available.

Analysis of Kell blood group system using polymerase chain reaction-restriction fragment-single strand conformation polymorphism combined with heteroduplex in Chinese / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the polymorphism of Kell blood group system in Chinese and to find a suitable method for large scale screening.</p><p><b>METHODS</b>An analysis method of polymerase chain reaction-restriction fragment-single strand conformation polymorphism (PCR-RF-SSCP) combined with heteroduplex was established to detect abnormal sample in KEL exon 7-9 area, then sequencing was used to find out the mutation site.</p><p><b>RESULTS</b>Two mutations were found from 500 samples: 966G > A mutation in exon 9 and C > A mutation in 67th site of intron 7, both with no amino acid change. The mutation rate was 4/1000. No mutation was found as missed in using PCR-RF-SSCP combined with heteroduplex.</p><p><b>CONCLUSION</b>PCR-RF-SSCP combined with heteroduplex is confirmed as an effective, economical and simple method, it is quite suitable for large scale population screening study with unclear gene background and unavailable positive controls. Since there is special polymorphism for Kell blood group system in Chinese, further study is needed.</p>

Anti Kell allo-antibody in a thalassaemic.

We describe a case of incidental detection of anti Kell antibody in a child with transfusion dependent thalassaemia. Kell antibody detection may be missed by routine indirect antiglobulin test (IAT) crossmatch procedure because of low prevalence of Kell antigen in the general population. A false negative result can be avoided by using sensitive cross matching techniques and screening cells representing antigens in homozygous state, against all clinically significant antibodies. A transfusion alert card describing the nature of antibody and future transfusion policy should be given to such allo-immunized patients.

Red cell alloimmunization in thalassaemia patients

To determine the frequency of red cell alloantibodies in a thalassaemia patient and to identify the common alloantibodies. A retrospective review of blood bank records for all thalassaemia patients. The records included, request received for blood group typing, antibody screen, antibody identification and cross-matching during the period between October 1st, 1997 to September 30, 2002. The history of blood transfusion was reviewed and the frequency rate for alloantibodies was determined. Out of 76 thalassemic patients, nine [11.8%] had developed alloantibodies. Alloantibodies detected include: nonspecific antibodies 3 [33.3%], anti E and nonspecific 2 [22.2%], anti-K together with non specific antibodies 1 [11.1%], anti-E 1 [11.1%], anti E together with anti K and nonspecific alloantibodes 1 [11.1%], anti-Lea 1 [11.1%]. Red cell alloantibodies developed in 11.8% of thalassemic patients. The most common alloantibodies were Rhesus and Kell antibodies, which are present in 33.3% and 22.2% of these patients respectively. Alloimmunization is not an uncommon problem facing blood banks and finding compatible units for regularly transfused thalassemic patients may be very difficult. In order to reduce alloimmunization a policy for performing extended red cell phenotyping on these patients is essential and at least antigen Kell and E negative blood should be provided for transfusion to these patients