The rare holley antibody associated with a severe hemolytic transfusion reaction: the importance of this antibody identification to find a compatible blood unit / Raro anticorpo associado à reação transfusional hemolítica grave: a importância de sua identificação para encontrar uma unidade sanguínea compatível

ABSTRACT The correct identification of erythrocyte antibodies is fundamental for the searching for compatible blood and haemolytic transfusion reactions prevention. Antibodies against antigens of high prevalence are difficult to identify because of the rarity of their occurrence and unavailability of negative red cells for confirmation. We report a case of 46-years-old woman, diagnosed with hemoglobinopathy, and who had symptomatic fall in hemoglobin levels (5.3g/dL) after blood transfusion suggestive of transfusion reaction. The patient's blood type was O RhD-positive. Irregular antibody screening was positive and demonstrated a panreaction against all erythrocytes tested, but this result was not reactive with dithiothreitol. Using negative red cells for antigens of high prevalence of our inventory we could identify in the serum of the same erythrocytes an anti-Holley antibody associated with anti-E. Molecular analysis confirmed that the patient was negative for E and Holley antigens. The crossmath with compatible units confirmed the results. Holley is a high prevalence antigen of the Dombrock blood system whose negative phenotype is extremely rare in all populations and is associated with hemolytic transfusion reactions. This is an antibody that is difficult to identify because laboratories need to have experience in solving complex cases, and have available a large stock of rare sera and erythrocytes, as well other tools such as enzymes, thiol reagents and molecular tests. The correct identification of a rare antibody is initial and mandatory for searching of compatible donors, and to guarantee a satisfactory transfusional support.

RESUMO A correta identificação dos anticorpos eritrocitários é fundamental na busca de sangue compatível e na prevenção das reações transfusionais hemolíticas. Anticorpos contra antígenos de alta prevalência são de difícil identificação, devido à raridade de sua ocorrência e à indisponibilidade de hemácias negativas para sua confirmação. Apresentamos aqui o caso de uma paciente do sexo feminino, 46 anos, com diagnóstico de hemoglobinopatia, que apresentou queda sintomática dos níveis de hemoglobina (5,3g/dL) após transfusão sanguínea, sugestiva de reação transfusional. O tipo sanguíneo da paciente era O RhD-positivo. A pesquisa de anticorpos irregulares foi positiva, demonstrando panreação contra todos os eritrócitos testados, mas não reativo ao ditiotreitol. Utilizando hemácias selecionadas negativas para antígenos de alta prevalência do nosso inventário, foi possível identificar no soro da mesma um anticorpo anti-Holley associado a um anti-E. A análise molecular confirmou que a paciente era negativa para os antígenos E e Holley, e as provas de compatibilidade com unidades fenotipadas confirmaram os resultados. Holley é um antígeno de alta prevalência do sistema sanguíneo Dombrock, cujo fenótipo negativo é extremamente raro em todas as populações e está associado a reações transfusionais hemolíticas. Trata-se de anticorpo de difícil identificação, pois os laboratórios precisam ter experiência na resolução de casos complexos, grande estoque de soros e eritrócitos raros, além de outras ferramentas, como enzimas, reagentes tiol e testes moleculares. A identificação correta de um anticorpo raro é inicial e obrigatória para a busca de doadores compatíveis, garantindo um suporte transfusional satisfatório.

Prevalência de aloimunização eritrocitária em pacientes portadores de anemia falciforme / Prevalence of red blood cell alloimmunization in patients with sickle cell anemia

Embora as transfusões de concentrado de hemácias sejam importantes para o tratamento de pacientes com anemia falciforme, elas acarretam riscos imunológicos tais como a aloimunização a antígenos eritrocitários. Aproximadamente 50% dos pacientes de anemia falciforme recebem transfusões no decorrer da vida, e entre 5% a 10% destes pacientes são submetidos a um programa de transfusão crônica. A aloimunização eritrocitária é uma complicação séria da transfusão, mas relativamente comum. Esta condição pode inclusive levar a reações transfusionais hemolíticas tardias e contribuir para aumentar as comorbidades da doença. Importantes medidas para prevenção destas complicações nestes pacientes são o uso de hemácias previamente fenotipadas, além da fenotipagem do próprio receptor de concentrado de hemácias, determinando seu correto perfil fenotípico e possibilitando a escolha de concentrado de hemácias com antígenos correspondentes ao do paciente a ser transfundido. Extensa genotipagem eritrocitária profilática para selecionar doadores para pacientes que receberão repetidas transfusões durante um longo período é uma aplicação atraente de tipagem de sangue baseados em DNA. Isto é, particularmente relevante para pacientes com doença falciforme onde a taxa de aloimunização é elevada.

Although packed red blood cells transfusions are important for treating patients with sickle cell anemia, this intervention may lead to immunological disturbs, such as alloimmunization by erythrocyte antigens. Approximately 50% of patients with sickle cell anemia receive blood transfusions during their life span, and about 5 to 10% of them require a chronic transfusion scheme. The red blood cell alloimmunization is a serious but common transfusion reaction. This condition could lead to delayed hemolytic transfusion reactions, contributing to increase comorbidities of the disease. Important measures to prevent these complications in patients are the use of previously phenotyped red blood cells, in addition to the phenotyping of red blood cells from the acceptor patient, determining the correct phenotypic profile and enabling the choice of red blood cells with corresponding antigens to the patient to be transfused. Extensive prophylactic red blood cell genotyping to select donors for patients receiving repeated transfusions over a long period of time is a compelling application of DNA-based blood typing. This is particularly relevant for patients with sickle cell disease where the rate of alloimmunization is high.

2016: medio centenario del Instituto de Hematología e Inmunología / 2016: half a century of the Institute of Hematology and Immunology

El primero de diciembre de 2016 arribará a sus cincuenta años de fructífera existencia el Instituto de Hematología e Inmunología (IHI), surgido por voluntad del Ministerio de Salud Pública de la República de Cuba con el objetivo de realizar las investigaciones biomédicas en sus ramas, garantizar la cobertura nacional de especialistas y brindar atención médica de alta calificación a nuestro pueblo en sus especialidades. El IHI inició sus actividades con solamente 4 médicos, 2 técnicos, 2 enfermeras, y escasos recursos proporcionados por los hospitales que le han servido de sede: General Docente Enrique Cabrera y Pediátrico Docente William Soler , ya que, contrario a la mayoría de las especialidades médicas en Cuba, la Hematología surgió durante el proceso revolucionario y se desarrolló plenamente con la creación del instituto. La Inmunología, como ciencia nueva en aquella época, comenzó también a desarrollarse a raíz de la creación del instituto...

El antígeno Diego alcanza los 60 años de edad: su descubrimiento y desarrollo / Diego antigen reach 60 years old: discovery and development

El antigeno Diego fue descubierto en junio de 1953 por el hematólogo estadounidense Philip Levine (1900-1987) en una muestra de sangre enviada desde Venezuela por el pediatra Miguel Raga Mendoza (1917-1986). El propósitus, de nombre Diego, había fallecido a los 3 días de edad por causa de una enfermedad hemolítica del recién nacido. Levine bautizó al nuevo antigeno con el nombre de diego y lo clasificó como un factor privado o familiar de baja prevalencia. En 1955, los hematólogos Miguel Layrisse (1919-2002) y Tulio Arents (1918-1990), y el obstetra Rafael Dominguez Sisco (1908-1980) llegaron a la conclusión de que el antígeno Diego tenía una mayor frecuencia que la reportada por Levine y que por tanto constituía un grupo sanguíneo de alta prevalencia en poblaciones indigenas venezolanas. Estos resultados fueron extendidos a otras poblaciones indígenas de América, demostrandose también su existencia en personas de origen asiático (mongoloides) y su ausencia en las razas caucasoide y negroide. El antígeno Diego se transformó así en el primer marcador mongoloide de gran valor antropológico, genético y clínico. En la década de 1990 se demostró que el antígeno Diego estaba asociado con la proteína eritrocitaria denominada banda 3; esta funciona como un intercambiador de aniones (AE-1) que se expresa también en células del túbulo renal. Actualmente, el grupo snguíneo Diego está formado por 22 antígenos o alelos.

On June 1953, the American hematologist Philip Levine (1900-1987) discovered a new erythrocyte antigen in the blood of a sick child collected in Venezuela by the pediatrician Miguel Raga Mendoza (1917-1986). The propositus, named Diego, was affected by a hemolytic disease of the newborn and died 3 days after delivery. Levine named the antigen Diego (Diª) and classified it as a private or familial factor of low prevalence. In 1955, the hematologists Miguel Layrisse (1919-2002) and Tulio Arends (1918-1990), and the obstetrician Rafael Dominguez Sisco (1908-1980) concluded that the Diego antigen had a greater frecuency than that reported by Levine, constituting a blood group of high prevalence in Venezuelan aboriginal populations. Similar results were obtained in other aboriginal populations of the American continent. The Diego antigen was also present in high frequency in people of asiatic origin (mongoloids), and absent in caucasoid and negroid people. Thus, the Diego antigen became the first mongoloid marker of great anthropological, genetic and clinical importance. In 1992, the Diego antigen was found associated with the erythrocyte protein named band 3, later known to function as an anion exchanger (AE-1). Band 3 is also expressed on cells of the renal tubules. Presenthy, the Diego blood group is formed by 22 antigens or allelles.

Blood transfusion-related immunomodulation

The phenomenon of transfusion-related immunomodulation (TRIM) has been studied since the observation of a higher kidney allograft survival in patients who had received a higher number of transfusions. Conversely, it has been suggested as one of the possible causes related to the development of infections in patients with multiple blood transfusions and/or after a major surgery, and has been also associated with a decreased function of natural killer cells (NK) and antigen-presenting cells (APCs), reduced cell-mediated immunity, and increased regulatory T cells (Tregs). This review aimed to conceptualize TRIM and discuss some aspects related to its mechanisms and the prevention of immunomodulatory events.

Estudio de las variantes alélicas del gen FUT2 en una población de Rosario, Santa Fe / Allele of FUT2 gen variables in a population of Rosario, Argentina

El estado secretor de un individuo está determinado por el gen Secretor (FUT2), responsable de la presencia de antígenos ABH en las secreciones del organismo. El polimorfismo del gen FUT2 muestra una gran variabilidad dependiente del tipo de población. Alrededor del 20% de los individuos caucásicos son no­secretores y presentan la mutación G428A. El objetivo de este trabajo fue estudiar las variables alélicas del gen FUT2 en una población de Rosario. Se trabajó con muestras de sangre periférica de dadores voluntarios (n=1728). Se determinó el estado secretor en plasma y saliva y el fenotipo Lewis. El ADN genómico fue extraído por la técnica de salting-out modificada y fue analizado por ASA-PCR con cebadores específicos para el alelo G428A y para el alelo wild type del gen FUT2. Los resultados obtenidos mostraron que el 77% de los individuos investigados fueron secretores y presentaron el fenotipo Lewis Le(a-b+). El polimorfismo G428A estuvo presente en homocigosis en un 7.5%, valor menor al reportado en la bibliografía para la población caucásica. El análisis molecular del gen FUT2 confirmaría la diversidad genética de la población investigada y podría ser utilizada como un marcador poblacional.

The secretor status is determinate by the secretor gene (FUT2) responsible of the ABH antigens expression in human secretions. About 20% of Caucasian individuals are non-secretors. The aim of this study was to study the allelic varieties of the FUT2 gene by a PCR reaction. We worked with peripheral blood samples of volunteers (n= 1728). We determinated the secretor status in plasma and saliva. The genomic DNA was extracted by an enzymatic digestion method and was analyzed by ASA-PCR with specific primers for the G428A allele and for the wild type allele of the FUT2 gene. The results obtained by serologic and molecular methods showed that the 77% of the investigate individuals were secretors. The G428A polymorphism had present in a 7.5%. The allelic varieties of the other non-secretor individuals different to the G428A might to correspond to other mutations. The molecular analysis of the FUT2 gene confirms the genetic diversity of the investigated population.

Hemolytic Disease of the Newborn Associated with Anti-Jr(a) Alloimmunization in a Twin Pregnancy: The First Case Report in Korea / 대한진단검사의학회지

Jr(a) is a high-frequency antigen found in all ethnic groups. However, the clinical significance of the anti-Jr(a) antibody has remained controversial. Most studies have reported mild hemolytic disease of the newborn and fetus (HDNF) in Jr(a)-positive patients. Recently, fatal cases of HDNF have also been reported. We report the first case of HDNF caused by anti-Jr(a) alloimmunization in twins in Korea. A 33-yr-old nulliparous woman with no history of transfusion or amniocentesis was admitted at the 32nd week of gestation because of vaginal bleeding caused by placenta previa. Anti-Jr(a) antibodies were detected in a routine laboratory examination. An emergency cesarean section was performed at the 34th week of gestation, and 2 premature infant twins were delivered. Laboratory examination showed positive direct antiglobulin test and Jr(a+) phenotype in the red blood cells and the presence of anti-Jr(a) antibodies in the serum in both neonates. The infants underwent phototherapy for neonatal jaundice; this was followed by conservative management. They showed no further complications and were discharged on the 19th postpartum day. Preparative management to ensure the availability of Jr(a-) blood, via autologous donation, and close fetal monitoring must be performed even in cases of first pregnancy in Jr(a-) women.

Comparison of the Frequencies and Distributions of Unexpected Antibodies Based on Different Calculation Criteria / 대한진단검사의학회지

BACKGROUND: The frequencies and distributions of unexpected antibodies have been reported using two different criteria, based on either number of persons tested or number of tests performed. But there has been no study that compared the results of analyses based on these two different criteria using the same data set. METHODS: Unexpected antibody tests performed in a University Hospital during recent 6 yr (January 2002-December 2007) were retrospectively analyzed: 76,985 tests (59,503 persons) for screening and 875 tests (749 persons) for identification. Data were analyzed using two different criteria, based on 'persons tested' and 'tests performed'. Antibodies had been screened and identified using LISS/Coombs gel cards with DiaMed-ID system (DiaMed AG, Switzerland). RESULTS: Frequencies of unexpected antibodies based on 'persons tested' and 'tests performed' were 1.32% and 1.34%, respectively (P=0.88). For frequently detected as well as rarely detected antibodies, there were no significant differences in the frequencies based on two different criteria. However, for rarely detected antibodies (anti-Xg(a) and Anti-E & D), the frequencies based on 'tests performed' were higher than those based on 'persons tested', affecting a change in the order of frequencies of antibodies detected. CONCLUSIONS: As there were no significant differences in the frequencies of unexpected antibodies calculated using two different criteria, both criteria can be used together for the patient population in our hospital. However, two criteria should be compared to validate the results for other populations.

Búsqueda e identificación de anticuerpos irregulares en la población de Antofagasta / Screening and identification of irregular antibodies in population of Antofagasta

In the last years, the medicine transfusional has generated big advances in the area of the conservation and managing of the blood fractions, especially in the detection of incompatibilities between donors and recipients, using monoclonal antibodies powerful and new methods that detect antibodies in very low concentrations. The majority of the blood banks agree to provide compatible blood for the antigens ABO and Rho (D), because opposite to them the antibodies produce the more severe transfusional reactions. Nevertheless, there are many reactions that seemingly slip by for the clinical one in 4 hours later to the transfusion, period in which a narrower alertness is had in the patient. These antibodies (irregular antibodies) involved in many late reactions are capable of haemolyse red cells incompatible after 12, 24 or up to 72 hours of realized the transfusion, causing the death to the patient when the haemolysis is intravascular, without its manages to suspect that the reason was a reaction transfusional. This work had as general aim detect and identify the presence of irregular antibodies in samples tried of recipients and donors of the Bank of Blood of the Regional Hospital of Antofagasta, proving that the major number corresponded to the system Kell, with an incident of 25.42% of the Anti K O positive, 16.95% of the Anti K A positive.

En los últimos años, la medicina transfusional ha generado grandes avances en el área de la conservación y manejo de las fracciones sanguíneas, especialmente en la detección de icompatibidades entre donantes y receptores, utilizando antisueros monoclonales potentes y nuevos métodos que detectan anticuerpo concentraciones muy bajas. La mayoría de bancos de sangre se conforman, con proporcionar sangre compatible para los antígenos ABO y (D), porque frente a ellos los anticuerpos producen las reacciones transfusionales más severas. Sin embargo, hay muchas reacciones que aparentemente pasan inadvertidas para el clínico en las 4 horas posteriores a la transfusión, período en el que se tiene una vigilancia más estrecha en el paciente. Estos anticuerpos (anticuerpos irregulares) implicados en muchas reacciones tardías son capaces de hemolizar eritrocito es incompatibles después de 12, 24 o hasta 72 horas de realizada la transfusión, ocasionando la muerte al paciente cuando la hemólisis es intravascular, sin que se llegue a sospechar que la causa fue una reacción transfusional. Este trabajo tuvo como objetivo general detectar e identificar la presencia de anticuerpos irregulares en muestras procesadas de receptores y donantes del Banco de Sangre del Hospital Regional de Antofagasta, resultando que el mayor número correspondió al sistema Kell, con una incidencia de 25,42% del Anti K O positivo, 16,95% del Anti K A positivo.

Prevalência dos tipos sangüíneos A, B e AB em gatos domésticos mestiços da cidade de Porto Alegre, Rio Grande do Sul, Brasil / Prevalence of blood types A, B and AB in mixed breed domestic cats of Porto Alegre, Rio Grande do Sul, Brazil

O presente estudo teve como objetivo determinar a prevalência dos tipos sangüíneos em felinos domésticos, mestiços, da cidade de Porto Alegre, Rio Grande do Sul, Brasil. Foram selecionados aleatoriamente 100 gatos, clinicamente saudáveis, mestiços e sem parentesco entre si. Amostras de sangue foram coletadas da veia jugular e a tipagem sangüínea foi realizada através do teste Rapid Vet H Feline (DMS Laboratories, Flemington, USA) e do teste hemaglutinação em tubo de ensaio. A tipagem reversa foi realizada para confirmar o tipo e a presença de aloanticorpos naturais. No presente estudo encontrou-seprevalência de 97% e 3% de gatos do tipo A e B, respectivamente. Não foram encontrados gatos do tipo AB. Os resultados indicam que no sul do Brasil há uma alta prevalência de gatos domésticos mestiços do tipo A, entretanto a prevalência de gatos do tipo B encontrada no trabalho é mais alta do que aquelas relatadas em alguns países. O conhecimento da prevalência dos tipos sangüíneos da população de gatos de uma região pode auxiliar na determinação dos riscos de reações transfusionais e de ocorrência de isoeritrólise neonatal, e estes podem ser prevenidos através de tipagem sangüínea e teste de compatibilidade sangüínea.

The present study was carried out to determine the prevalence of the blood types in mixed breed domestic cats of Porto Alegre, Rio Grande do Sul, Brasil. A hundred of clinically healthy mixed breed and non related cats were selected. Blood samples were collected from the jugular vein and the blood typing was performed by Rapid Vet H Feline test(DMS Laboratories, Flemington, USA) and by hemagglutination tube test. Reverse blood typing was done to confirm the blood types and the presence of alloantibodies. In the present study the prevalence of blood type A and B in cats were 97% and 3%, respectively. No AB blood type cats were found. These results indicate that there is a high prevalence of blood type A mixed breed domestic cats in the south of Brazil, although the prevalence o B cats found is higher than reported in some countries. The knowledge of feline blood types prevalence in cat population can help to determine the risks of transfusion reactions and neonatal isoerythrolysis, and these can beavoid by blood typing and cross-matching test.

Aloantígenos de granulocitos. Importancia clínica / The granulocyte alloantigens. Clinical importance

Los aloantígenos de granulocitos se agrupan en 2 grandes categorías: antígenos específicos de granulocitos y antígenos cuya distribución es más amplia y comprende otras líneas celulares. En 1998 se acordó establecer una nueva nomenclatura de los aloantígenos de granulocitos, basada en la localización glucoproteica de estos antígenos. La molécula FcgRIIIb es un miembro de la superfamilia de inmunoglobulinas (CD 16) en la cual se asientan varios de los aloantígenos específicos de granulocitos. Existen otros aloantígenos cuya función y localización se desconocen. Estas moléculas son de gran importancia clínica, pues se ven envueltas en una serie de enfermedades como la neutropenia neonatal aloinmune, cuyo carácter clínico moderado hace que pase inadvertida, la reacción febril no hemolítica, el daño pulmonar agudo relacionado con la transfusión, la neutropenia inmune asociada con el trasplante de médula ósea y la neutropenia autoinmune. Aunque se han producido avances en la caracterización de los aloantígenos de granulocitos, muchos puntos quedan sin aclarar, entre ellos, la significación clínica de muchos antígenos. El desarrollo creciente de técnicas moleculares, bioquímicas y serológicas para el estudio de los antígenos de células sanguíneas, nos permitirá aclarar los puntos que aún permanecen oscuros en este campo de la investigación