Serologic strategy in detecting RHD altered alleles in Brazilian blood donors

ABSTRACT Background: We evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors. Methods: We selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spin (IS) with eleven commercially available anti-D reagents in a tube and microplate. The D confirmatory tests for the presence of weak D included the indirect antiglobulin test (IAT) in a tube, gel and solid-phase red blood cell adherence (SPRCA). All DNA samples were extracted from peripheral blood and the D variants were classified using different molecular assays. Results: The RHD variants identified by molecular analysis included weak D types (1, 2, 3, 11 and 38) and partial Ds (DAR1.2, DAR1, DAR3.1, DAU0, DAU2, DAU4, DAU5, DAU6, DMH and DVII). The monoclonal-monoclonal blend RUM-1/MS26 was the best anti-D reagent used in detecting the D antigen in the IS phase in a tube, reacting with 83.2% of the D variants, while the anti-D blend D175 + 415 was the best monoclonal antibody (MoAb) used in a microplate to minimize the need for an IAT, reacting with 83.2% of the D variants. The D confirmatory tests using SPRCA showed a reactivity (3 - 4+) with 100% of the D variant samples tested. Conclusion: Our results show that, even using sensitive methods and MoAbs to ensure the accurate assignment of the D antigen, at least 17% of our donor samples need a confirmatory D test in order to avoid alloimmunization in D-negative patients.

Sistema Rh-Hr y variantes del antígeno D en tres poblaciones afroecuatorianas del Valle del Chota / Rh-Hr system and D antigen variants in three Afro-Ecuadorian populations in the Chota Valley / Sistema Rh-Hr e variantes do antígeno D em três populações afro-equatorianas no vale do Chota

Resumen La identificación inequívoca del antígeno D en medicina transfusional es de vital importancia para evitar reacciones postransfusionales y la enfermedad hemolítica del recién nacido. Es común el uso de reactivos serológicos monoclonales o tarjetas de gel y su interpretación está definida por cruces, de acuerdo con la reacción serológica. El propósito de este estudio fue determinar la frecuencia del factor Rh y las variantes del antígeno D en una población afroecuatoriana. Se trató de un estudio descriptivo, transversal con muestreo aleatorio simple de 541 pobladores. Para la tipificación del factor Rh se utilizó la metodología en tubo con antisueros monoclonales y para la detección de las variantes de D se utilizaron tarjetas de gel IDCoombs Anti-IgG. Las lecturas se verificaron mediante el análisis del índice kappa. Se aplicó estadística descriptiva y el análisis de Chi cuadrado para establecer la relación de las variables y su significación. Se identificó una frecuencia del 92% de individuos Rh(D) positivo y un 8% Rh(D) negativo. El 4,80% de los individuos presentaban la variante D débil y el 79% reacciones serológicas entre 2 y 3(+) indicativas de otras variantes del antígeno D. El fenotipo más común fue el R0/R0. Estos datos demuestran la necesidad de confirmar la existencia de variantes del antígeno D en esta población para un mejor manejo de la sangre. Una limitante constituye la disponibilidad de técnicas moleculares para la genotipificación de D; sin embargo, se podría implementar la fenotipificación RHCE como estrategia pretransfusional.

Abstract The unequivocal identification of D antigen in transfusion medicine is of vital importance to avoid post-transfusion reactions and hemolytic disease of the newborn. The use of monoclonal serological reagents or gel cards is common and their interpretation is defined according to the serological reaction by crosses. The purpose of this study was to determine the frequency of Rh factor and D antigen variants in the Afro-Ecuadorian population. This was a descriptive, cross-sectional study with simple random sampling of 541 residents. Tube typing with monoclonal antisera was used to typify Rh factor and ID-Coombs Anti-IgG gel cards were used to detect D variants, and the readings were verified by analysis of the kappa index. Descriptive statistics and Chi-square analysis were applied for the relationship of the variables and their significance. A frequency of 92% of Rh(D) positive individuals and 8% Rh(D) negative individuals were identified. Almost 5% (4.80%) of the individuals presented the weak D variant and 79% serological reactions between 2-3(+) indicative of other D antigen variants, the most common phenotype being R0/R0. These data demonstrate the need to confirm the existence of D antigen variants in this population for better management and availability of blood. A limitation is the availability of molecular techniques for D genotyping, however, RHCE phenotyping could be implemented as a pretransfusion strategy.

Resumo A identificação inequívoca do antígeno D na medicina transfusional é de vital importância para evitar reações pós-transfusionais e a doença hemolítica do recém-nascido. É comum o uso de reagentes sorológicos monoclonais ou cartões de gel e sua interpretação é definida por cruzamentos de acordo com a reação sorológica. O objetivo deste estudo foi determinar a frequência do fator Rh e as variantes do antígeno D numa população afro-equatoriana. Foi um estudo descritivo, transversal, com amostragem aleatória simples de 541 residentes. Para a tipagem do fator Rh foi utilizada a metodologia em tubo com anti-soros monoclonais e para a detecção das variantes de D, os cartões de gel ID-Coombs Anti-IgG. As leituras foram verificadas por análise do índice kappa. Foi aplicada estatística descritiva e para estabelecer a relação das variáveis e sua significação se utilizou a análise do qui-quadrado. Identificando uma frequência de 92% dos indivíduos Rh (D) positivos e 8% Rh (D) negativos. 4,80% dos indivíduos apresentavam a variante D fraca e 79% reações sorológicas entre 2 e 3(+) indicativas de outras variantes do antígeno D, sendo o fenótipo mais comum o R0/R0. Esses dados demonstram a necessidade de confirmar a existência de variantes do antígeno D nessa população para melhor gerenciamento e disponibilidade de sangue. Uma limitação é a disponibilidade de técnicas moleculares para a genotipagem de D, no entanto, a fenotipagem de RHCE poderia ser implementada como uma estratégia de pré-transfusão.

Procedencia y fenotipo del sistema Rh en donantes negativos en un Hemocentro colombiano / Origin and phenotype of the Rh system in negative donors in a Colombian hemocenter

percentIntroducción: El sistema Rh está compuesto por más de 56 antígenos capaces de producir enfermedad hemolítica, definidos por métodos serológicos. Los más importantes y, por ello denominados antígenos mayores del sistema, son los antígenos D, C, c, E y e. Estos antígenos se ubican sobre dos proteínas que se expresan en la membrana de los eritrocitos Rh D y RhCE. Objetivo: Determinar la frecuencia de los antígenos C, c, E y e del sistema Rh en donantes de sangre Rh negativos del Hemocentro Centro Oriente Colombiano. Métodos: Estudio descriptivo de corte transversal que incluyó 193 donantes voluntarios de sangre del Hemocentro Centro Oriente Colombiano, la fenotipificación de los antígenos del sistema Rh se realizó utilizando la técnica en tarjeta gel. Se calculó la frecuencia fenotípica de los antígenos del sistema Rh, en porcentajes y para el procesamiento de la información se utilizó el paquete estadístico SPSS versión 21.0 donde se realizó el análisis de los datos de la población. Como criterios de inclusión ser donante voluntario de sangre y de exclusión, estar hemoclasificado como antígeno DEL, D débil y D parcial. Resultados: Las muestras analizadas fueron obtenidas de la tubuladura central de la unidad fraccionada de glóbulos rojos, identificándose tres fenotipos con la siguiente frecuencia: cde/cde (95,86 por ciento), cde/cdE (3,10 por ciento) y cde/Cde (1,04 por ciento). Los participantes del estudio provenían de diversos municipios del departamento de Boyacá y otras regiones del país como llanos Orientales, Santander y Cundinamarca. Los antígenos del sistema Rh son altamente polimórficos a nivel de poblaciones, dada la importancia inmunológica de los antígenos del sistema Rh, los cuales se ven directamente relacionados con el desarrollo de anemia hemolítica postransfusional y perinatal, la fenotipificación ampliada brinda mayor seguridad transfusional y seguimiento al estado del feto o neonato(AU)

Introduction: The Rh system is composed of more than 56 antigens capable of producing hemolytic disease, defined by serological methods; being the most important and therefore the largest antigens of the system, the antigens D, C, c, E and e. These antigens are located on two proteins that are expressed in the membrane of erythrocytes Rh D and RhCE. Objective: To determine the frequency of the C, c, E and e antigens of the Rh system in Rh negative blood donors of Hemocentro Centro Oriente Colombiano. Methods: A cross-sectional descriptive study that included 193 blood donors from the Hemocentro Centro Oriente Colombiano, phenotyping the antigens of the Rh system, using the gel card technique. The phenotypic frequency of the Rh antigen was calculated, in percentages and for the processing of the information, the statistical package SPSS version 21.0 was used in Spanish where all the analysis of the population data was performed. With inclusion criteria to be a voluntary blood donor and exclusion, be hemoclasified as DEL antigen, weak D and partial D. Results: The analyzed samples were obtained from the central tubulant of the fractionated unit of red blood cells, three phenotypes were identified with a frequency of :cde / cde95.86 percent, cde / cdE 3.10 percent and cde / Cde 1, 04 percent; it was evidenced that the participants come from diverse municipalities of the department of Boyacá and other regions of the country like Eastern Plains, Santander and Cundinamarca. The Rh factor and the antigens of the Rh system are highly polymorphic at the population level, given the immunological importance of the antigens of the Rh system, which are directly related to the development of post transfusion hemolytic anemia and perinatal hemolytic disease, the extended phenotyping provides greater transfusional safety and follow-up to the status of the fetus or neonate(AU)

Digital dermatoglyphis in ABO, Rh blood groups.

Dermatoglyphics, the study of fingerprints are constant and individualistic. The ridge pattern depends upon cornified layer of epidermis as well as dermal papillae. This study was conducted to correlate between digital dermatoglyphics patterns in ABO, Rh blood groups and evaluates their significance. A total of 200 first year MBBS students with known blood groups from 2004 and 2005 batch of IGGMC, Nagpur were included in the study. Fingerprints were obtained by printing method. Parameters studied were arches, whorls, loops. It was concluded that, whorls were highest in B blood group and the difference was significant with O blood group. Loops were highest in O blood group and were significant with A, B, AB blood groups. Arches were highest in AB blood group and were statistically significant with B and O blood groups. Arches were higher in Rh negative blood group differing statistically with Rh positive blood group.

Weak D antigen - Revisited.

D antigen is the most immunogenic antigen in the complex Rh blood group system discovered in the year 1939. There is a lot of polymorphism in its phenotype due to genetic heterogeneity. Certain mutations and /or deletions lead to a weak phenotype defined by decreased density of antigen sites which require the use of anti human globulin for detection. The need for detection of the weak D antigen was to prevent alloimmunization by this blood if transfused to a D negative patient especially to women in child bearing age group. This contention is however, controversial and not proven beyond doubt. Moreover, the use of potent monoclonal D typing antisera detects low density of weak D antigens thus obviating the use of anti human globulin. We have assessed the incidence of Rh negative and weak D blood groups in the Garhwal region of Uttarakhand and reviewed the literature regarding the controversies in the clinical significance of weak D antigen.

ABO blood groups and Rhesus factor: An exploring link to periodontal diseases.

Background: The presence or absence of blood group antigens has been associated with various diseases, with antigens also acting as receptors for infectious agents. Scanty literature is available in assessing the relative liability of blood group phenotypes to periodontal diseases. This research was conducted to determine the association of the ABO blood group and Rhesus (Rh) factor to periodontal diseases to assess whether they could be the predictors of periodontal diseases. Materials and Methods: A total of 1,220 subjects aged between 20 and 55 years were selected on a random basis. The study populations were segregated into three groups according to Ramfjord's periodontal disease index: Healthy, Gingivitis and Periodontitis. Blood samples were collected to identify the ABO blood groups and the Rh factor by the slide method. Results: Blood group A showed a significantly higher percentage in the gingivitis group and blood group O showed a higher percentage in the periodontitis group. The blood group AB showed the least percentage of periodontal diseases. The distribution of Rh factor in all groups showed a significantly higher distribution of Rh-positive. Conclusion: The genetic factors may alter the oral ecology and the process of periodontal disease. These data are suggestive of a broad correlation between periodontal diseases and blood groups, which may act as risk predictors for periodontal diseases. This will make it possible to better-understand the risk factors of diseases of the periodontal tissues and to predict the effective methods of prevention and treatment of periodontal diseases.

Agenesia del tercer molar en una etnia originaria del Norte de Chile: atacameños o Lican Antai / Third molar agenesis in native ethnia from north of Chile: atacamenos or Lican Antai

Agenesia es la ausencia de dientes por alteraciones genéticas aisladas o sindrómicas. La agenesia del tercer molar está asociada a malformaciones y considerada por diversos autores consecuencia de la evolución humana (Larmour et al., 2005). Son los dientes con mayor prevalencia de agenesia junto a los segundos premolares e incisivos laterales (Fuller & Denehy, 1984). La prevalencia varía entre 9 y 37 por ciento (McNamara & Foley, 2006), en tanto, Arboleda et al. (2006) señalan una prevalencia del 20 por ciento. La literatura señala variables estadísticas porcentuales, por género, por arcada dentaria, por lado y por diente, con escasos artículos sobre grupos originarios de Chile. La población en estudio consistió en 33 hombres y 57 mujeres de 16 a 55 años, de la etnia atacameña, sin exodoncias del tercer molar ni tratamientos ortodónticos y sin malformaciones congénitas. Se determinó el grado de mestizaje mediante técnica serológica de hemo-aglutinación y por aplicación de la fórmula de Bernstein, que demostró 56 por ciento de mezcla indígena. A cada individuo se le tomó radiografía panorámica para observar presencia o ausencia de terceros molares. Se determina un 26,7 por ciento de individuos con agenesia de uno o más terceros molares, con mayor porcentaje en hombres. En la muestra y en hombres hay mayor agenesia de terceros molares mandibulares; en cambio, en mujeres existe mayor agenesia de terceros molares maxilares. Predominan agenesias izquierdas, lo mismo se comprueba en mujeres, mientras en hombres se comprueba igual porcentaje bilateral. Predomina la agenesia de dos molares en ambos sexos. No existen diferencias estadísticas significativas al 95 por ciento y los resultados coinciden con la literatura. La investigación representa un aporte a la antropología del Norte de Chile, pero considerando lo reducido de la muestra, no fue posible determinar variables étnicas.

Agenesis is the absence of teeth by genetic alterations, single or as syndrome. Agenesis of third molar is associated to malformations and is considered by diverse authors a consequence of the human evolution (Larmour et al., 2005). The third molars together with second premolars and lateral incisors are the teeth with greater prevalence of agenesis (Fuller & Denehy, 1984). The prevalence varíes between 9 percent and 37 percent (McNamara & Foley, 2006); Arboleda et al. (2006) indicated a prevalence of 20 percent. Literature indicate variable percentage, by gender, dental arches, side and tooth, with few arricies on original groups of Chile. The population in study consisted of 33 men and 57 women between 16 and 55 years of the ethnic group of atacameños, without extractions of third molar ñor orthodontic treatments and without congenital malformations. Hybridism was determined by means of serum technique by blood agglutination and by application of the formula of Bernstein, demonstrated a 56 percent of indigenous mixture. To each individual a panoramic x-ray was taken to observe presence or absence of third molars. A 26.7 percent of individuals with agenesis of one or more third molars was determined, with greater percentage among males. Agenesis lower third molar predominates in the sample and in men; however in women are greater agenesis upper third molar. In addition, agenesis predominates of the left side in both sexes, while in men equal bilateral percentage is verified. Agenesis of two molars predominates in both sexes. Statistical analyses did not show significant differences at the 95 percent level, and the results, in general, agree with those in the literature. This research represents a contribution to the anthropology of the north of Chile, but it is not possible to determine ethnic variables considering the small sample in study.

Varied distribution of RhD epitopes in the Indian population.

BACKGROUND: Inhabited by more than 4000 caste and tribal groups, India has an extremely heterogenous population. For thousands of years many tribal groups have practised endogamy and are practically genetically isolated. Traditionally, polyclonal anti-D reagent has been used for RhD typing; though monoclonal antibodies are increasingly being used. As a result, blood banks find it difficult to assign the RhD status to an increasing number of people. As monoclonal anti-D typing reagents may not detect all RhD antigen epitopes, we studied the RhD antigen epitope heterogeneity in different population groups in India. METHODS: Red cells of 5315 RhD-positive individuals belonging to different castes and tribes of India were tested with 30 different epitope-specific monoclonal anti-D antibodies. RESULTS: No single monoclonal antibody could detect all RhD-positive red cells detected by polyclonal antisera. The highest proportion of D antigen was detected by LHM 76/55 and BRAD-8 (98%) monoclonal antibodies. CONCLUSION: We need to determine the correct mix of monoclonal antibodies that will detect nearly all RhD antigens detected by polyclonal anti-D sera. Similarly, before accepting monoclonal anti-D for therapeutic use, it would be necessary to determine the appropriate ones for use in the Indian population.

Potential of commercial anti-D reagents in the identification of partial D variants in Indian population.

BACKGROUND & OBJECTIVE: As partial D variants are of clinical importance in transfusion medicine, the present study aims to determine the efficiency of commercial anti-D reagents to identify partial D variants. METHODS: Forty two samples of known partial D identified in the Indian population were tested with seven commercial monoclonal anti-D reagents. RESULTS: Most of the monoclonal anti-D reagents gave strong positive reactions (24 to 59%) to weak positive (28 to 47%) with partial D cells. Polyclonal anti-D detected all partial D variants as RhD positive, though reacting weakly with the majority (83%) of them. All the seven commercial monoclonal anti-D reagents detected some variants as D negative. Analysis of pairs of these reagents showed that the combinations of reagents 1 & 2 and 1 & 6 could detect all partial D variants as RhD positive and hence can be used for donor testing. INTERPRETATION & CONCLUSION: Findings of our study showed that none of the monoclonal reagents when used individually could detect all partial D variants. A combination of two suitable anti-D reagents are necessary to detect maximum number of partial D variants.

A RhD Negative Patient Failed to Produce Detectable Anti-D after Transfusion of 35 Units of RhD Positive Red Blood Cells / 대한진단검사의학회지

In the present day, pretransfusion tests include ABO and RhD grouping, antibody screening, antibody identification, and cross matching. Although error rates for these tests have decreased compared to those in the past, clerical errors still occur. When exposed to RhD positive RBCs, a RhD negative person can produce anti-D that causes a severe hemolytic disease of the fetus and the newborn in addition to hemolytic transfusion reactions. Therefore, administration of RhD positive RBCs to a RhD negative person should be avoided. We experienced a RhD negative patient who had been misidentified as positive and transfused 35 units of RhD positive RBCs eight years ago, but did not have detectable anti-D in present. The red cells of the patient showed no agglutination with the anti-D reagent and a negative result in the standard weak D test. The multiplex PCR with sequence-specific priming revealed that the patient was RhD negative.

A Case of Severe Hemolytic Disease of the Newborn Due to Anti-Di(a) Antibody / 대한진단검사의학회지

Here we report a severe case of hemolytic anemia of the newborn with kernicterus caused by anti-Di(a) antibody. A full term male infant was transferred due to hyperbilirubinemia on the third day of life. Despite single phototherapy, the baby's total bilirubin had elevated to 30.1 mg/dL. After exchange transfusion, total bilirubin decreased to 11.45 mg/dL. The direct antiglobulin test on the infant's red cells was positive. The maternal and infant's sera showed a negative reaction in routine antibody detection tests, but were positive in Di(a) panel cells. The frequency of the Di(a) antigen among the Korean population is estimated to be 6.4-14.5%. Anti-Di(a) antibody could cause a hemolytic reaction against transfusion or hemolytic disease of the newborn. We suggest the need for reagent red blood cell panels to include Di(a) antigen positive cells in antibody identification test for Korean.

Beneficios do programa de controle da qualidade em imunohematologia na pratica transfusional / Benefits of the quality control program in immunohematology in transfusion medicine

O Programa de Controle de Qualidade Externo em Imunohematologia foi introduzido com o objetivo de avaliar a qualidade do diagnóstico em Imunohematologia. Foram realizadas 41 avaliações em 223 instituições no período de 1992 a 2003 que incluíram testes de proficiência para determinação ABO e RhD, fenotipagem Rh e K, teste direto da antiglobulina humana, pesquisa de anticorpos irregulares e identificação de anticorpos. No período de 12 anos o programa incluiu 8014 determinações de grupo sanguíneo ABO, 8000 classificações RhD, 5193 fenotipagens Rh, 5101 fenotipagens K, 7939 pesquisas de anticorpos irregulares, 4533 identificações de anticorpos e 7912 testes diretos da antiglobulina humana. Respostas incorretas foram classificadas como erros clericais, técnicos, ou não determinados. Ocorreu um número elevado de erros clericais na determinação do grupo sanguíneo ABO (76/76 erros), classificação RhD (34/58 erros) e na fenotipagem Rh (50/73 erros). Erros técnicos ocorreram predominantemente na determinação do antígeno D fraco (91/95 erros), na pesquisa de anticorpos irregulares (252/301 erros) e na identificação de anticorpos (321/335 erros) e estavam...

The Brazilian External Quality Assessment Program in Immunohematology (BEQAPI) was introduced with the objective of evaluating the quality of diagnosis in Immunohematology. From 1992 to 2003, proficiency tests for ABO grouping, Rh (D, C, c, E, e), K phenotyping, Direct Antiglobulin Testing (DAT), Antibody Screening (AS) and Antibody Identification (AI) were performed. Forty-one evaluations were carried out in 223 institutions. Over the period of 12 years, the program included 8,014 ABO typing, 8,000 RhD typing, 5,193 Rh (C, c, E, e), 5,101 K phenotyping, 7,939 AS, 4,533 AI and 7,912 DATs. Erroneous responses were classified as clerical, technical or undetermined. A substantial proportion of erroneous responses due to clerical errors occurred in ABO typing (76/76 errors), RhD typing (34/58 errors) and Rh phenotyping (50/73 errors). Technical errors occurred predominantly for weak D (91/95 errors), AS (252/301 errors) and AI (321/335 errors). Based on these results, since 1996, participants have received "Questions and Case Studies" as an incentive for training and education. The results of the present study show an improvement in the performance of participants in the course of the program. We...

Profilaxis de la sensibilización Rh por transfución de plaquetas en pacientes Rh negativos / Prophylaxis of the sensibilization Rh by plaquet transfusion in negative Rh patients

La transfusión de componentes plasmáticos y celulares de la sangre es vital en numerosas situaciones clínicas; lo que, aunado a su constante escasez, obliga al clínico a recurrir a prácticas que pudiesen traeer alugna complicación posterior para el paciente. La transfusión de concentrados de plaquetas de donadores Rh positivos a pacientes Rh negativos, conlleva un riesgo de sensibilización a los antígenos Rh eritrocitarios, descrito hasta en un 19 por ciento. Las recomendaciones proponen el uso de la inmunoglobolina ant-Rh (D) preferiblemente por vía intravenosa, en mujeres Rh negativas aún antes de la edad fértil, tras la transfusión de componentes sanguíneos (plaquetas) de donadores Rh positivos. Nuestro objetivo es ofrecer una revisión de la información científica sobre el tema, con el fin de brindar elementos objetivos para mejor proceder ante la transfusión de plaquetas minimizar la sensibilización de los pacientes Rh negativos. Palabras clave: inmunoglobulina, plaquetas, Rh negativo, anticuerpos, transfusión, sensibilización.

Frecuencias de grupos sanguíneos e incompatibilidades ABO y RhD, en La Paz, Baja California Sur, México / Blood group frequencies and ABO and RhD incompatibilities in La Paz, Baja California Sur, Mexico

OBJECTIVE: To determine genic and phenotypic frequencies and predict the risk of incompatibility and maternal alloimmunization in the population of La Paz. MATERIAL AND METHODS: This descriptive study evaluated 1809 voluntary blood donors attending in 1998 the Hospital General de Zona of Instituto Mexicano del Seguro Social (Zone General Hospital of the Mexican Institute of Social Security) in La Paz, Baja California Sur, Mexico. Blood donors were typified by tube agglutination. The gene frequencies were estimated assuming equilibrium conditions, and incompatibilities and alloimmunization were statistically assessed with the chi 2 test. RESULTS: Percent frequencies were as follows: blood group O, 58.49; A, 31.40; B, 8.40; AB, 1.71; RhD, 95.36; and RhD negative, 4.64. Genic frequencies were: i, 0.7648; IA, 0.1821; IB, 0.0519; D, 0.7845; and d, 0.2155, respectively. Incompatibilities between couples and mother-child were 0.3023 and 0.1685 for ABO, 0.0442 and 0.0364 for RhD, and 0.0134 and 0.0061 for double incompatibility, respectively. The probability of maternal alloimmunization was estimated at 0.0309. CONCLUSIONS: The O and RhD groups were the most common in La Paz, although frequencies were among the lowest in Mexico, contrary to the case of A and RhD negative groups. The probabilities of maternal alloimmunization and of incompatibilities were also high. Ancestral white, black, and indigenous groups admixed in the northwestern part of Mexico; after migrating to Baja California Sur the admixture of the population probably became similar to that of the remainder of the northwestern area.

Prevención del síndrome de la abuela: estudio preliminar / Prevention of grandmother`s syndrome: preliminary study

Determinar la frecuencia de grupos ABO, Rh y los anticuerpos D en recién nacidas de madres Rh positivo. Se obtuvo rutinariamente una muestra de sangre del cordón de todas las recién nacidas, para determinar los grupos ABO, Rh y la presencia de anticuerpos anti D. A las neonatas Rh negativas sin anticuerpos se les administró una dosis estándar la inmunoglobulina específica (Rho-GAM) dentro de las 72 horas de su nacimiento. Hospital privado Centro Médico de Caracas. De las 145 recién nacidas, diecinueve fueron Rh negativo no sensibilizadas (13,10 por ciento). La muestra sistemática de sangre del cordón de recién nacidas permite detectar las Rh negativo de madres Rh positivo y la presencia o ausencia de anticuerpos anti-D. Este enfoque y la administración de inmunoglobulina a estas neonatas, podría prevenir el síndrome de la abuela. Se necesita evaluaciones más prolongadas en el tiempo para determinar los beneficios de esta conducta

ABO blood group and Rhd phenotypes in Bahrain: Results of screening school children and blood donors

Frequencies of ABO blood groups and Rh types show geographic variations. To estimate frequencies of ABO groups and Rh types in Bahraini subjects. Frequencies of ABO blood groups and Rh types along with the respective gene frequencies were estimated in two study groups: [1] 5675 Bahraini school students in age group 16-20years and [2] 7362 adult Bahraini blood donors. Frequencies of ABO groups in both study groups showed Group O>Group B>GroupA>Group AB. Both study groups also showed >90 percent frequency of the RhD phenotype. The frequencies of ABO and Rh phenotypes in Bahrain are similar to those reported from most areas in the Arabian Gulf region. These frequencies appear to be intermediate between Europe and south/south-east Asia

Asociación de marcadores eritrocitarios (ABO, MNSs, Rh, Lewis, P1) con recurrencias y anomalías anatómicas y funcionales en niños con infección del tracto urinario / Association of erythrocyt markers (ABO, MNSs, Rh, Lewis, P1) with recurrences and anatomical-functional abnormalities in children with urinary tract infection

Para contribuir a la identificación de niños con infección del tracto urinario con mayor riesgo de ubicación alta o baja, recurrencias y alteraciones radiológicas o ultrasonográficas (complicaciones) se estudiaron las asociaciones entre éstas y la distribución de marcadores eritrocitarios (ABO, MNSs, Rh, Lewis, P1) en 309 casos de infección urinaria. No se encontró asociación entre algún polimorfismo eritrocitario en particular con las mencionadas categorías, pero si entre el fenotipo P1 y la etiología Escherichia coli (OR=3,07; IC 95 porciento=1,13 a 8,6; p<0,02) y la ausencia de etiología no E. coli con el fenotipo B+(0/26) sin llegar a niveles de significación. Estos hallazgos sugieren que en niños con infección urinaria, estos fenotipos, por separado, probablemente tienen acciones independientes y aditivas