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Background: The large diversity of red blood cell antigens favors, especially in multi-transfused patients, the occurrence of autoimmunization and alloimmunization with the risk of hemolytic transfusion reactions. Thus, this study aimed to determine the rates of alloimmunization and autoimmunization in these individuals, as well as the types of alloantibodies and their systems, clinical and epidemiological aspects and the frequency of autoimmunity in alloimmunized and non-alloimmunized patients. Methods: In a retrospective study, 153 multi-transfused patients from 2006 to 2014 were evaluated. Sixty-eight had onco-hematological diseases, 64 had hemoglobinopathies and 21 had chronic renal failure. Descriptive analyses were carried out with the proportions being compared using the chi-square test, with the significance level set at 5%. Results: The Rh system was the most frequently involved (53.11%) and anti-E and anti-K (Kell system) were the most prevalent alloantibodies (21.87% each). Autoantibodies were found in ten patients (6.54%) with the percentages of autoimmunization in alloimmunized and non-alloimmunized individuals being 29.16% and 2.32%, respectively (p = 0.0001). There was a significant difference between autoimmunization and the number of transfusions (16.21% in 6–10 vs. 5.26% 10; p = 0.0203) and diseases (19.04% in chronic renal failure vs. 6.25% in hemoglobinopathies vs. 2.94% in onco-hematological diseases; p = 0.0329). Conclusion: The results show a strong correlation between alloimmunization and autoimmunization. Moreover, they reinforce the need for further studies on the clinical and epidemiological profile of multi-transfused patients in relation to alloimmunity and autoimmunity, especially the latter, for a better understanding of its etiopathogenesis and physiopathogenesis. Keywords: Multi-transfused patients, Red blood cell antibodies, Alloimmunization, Autoimmunization

Background and objectives The frequency of red blood cell (RBC) antigens in Brazil varies due to differences in the ethnic groups in different regions; however, these studies have not been performed in Minas Gerais, where African admixture is more prevalent in comparison with other states. Due to these facts, this study aimed to determine the frequency of RBC genotypes on Rh, Kell, Duffy and Kidd systems in blood donors and multi-transfused patients from Minas Gerais, Southeast Brazil. Methods Blood samples were collected from 170 donors and 117 patients with different diagnosis and at least three RBC transfusions. DNA was extracted from leukocytes and genotyped by PCR-SSP, Multiplex or RFLP to alleles of the referred systems. The results were compared by the Chi-Square test, with a significance level of 5%. Results The most frequent genotypes were: RHD+, RHCE*ce/RHCE*ce, KEL*2/KEL*2, FY*B-67T/FY*B-67T and JK*A/JK*B . FY*B-67C/FY*B-67C, RHD*Ψ and JK*A/JK*A genotypes were more prevalent in sickle cell disease (SCD) patients than in donors. Many differences in RBC genotype frequencies were observed in comparison with studies from other states and countries. Conclusion The results reinforce the importance of determining RBC genotypes of blood donors and patients in different regions of Brazil and the world, improving the transfusion safety of individuals requiring chronic RBC transfusions, especially those with SCD, due to ethnic differences in relation to donors.

Changes in weight/height ratio, delayed sexual maturation, hypogonadism and impaired fertility have been demonstrated in sickle cell disease (SCD). This study aimed to evaluate the clinical and laboratory views of the Leydig cells function after stimulation with hCG in adults with sickle cell disease. We studied 15 patients with SCD (18 to 40 years; median = 27 years old), fourteen homozygous S, and one with SC disease. The control group, composed by adult males, was divided into two groups: I — 10 relatives (18–39 years, median = 26 years) with the same socioeconomic level of the patients, and II — 9 normal individuals (23–28, median = 31 years) randomly chosen. Clinically it was observed a slight degree of malnutrition, important puberty delay, rarefaction of chest, underarm and pubic hair, and important reduction of the testis and penis size, featuring a mild hypogonadism in patients with SCD. The hormonal level assessment of testosterone at baseline and at 24, 48 and 72 h after hCG stimulation showed no significant differences between the groups studied. We can presume that adult men with SCD showed clinical hypoandrogenism with normal testicular hormonal function, a fact inconsistent with the hypothesis of primary hypogonadism.

INTRODUCTION: Within the context of transfusion safety, the immunohematological study of donors and recipients of blood products is currently the most fragile link in the transfusion chain of the public blood bank network of Minas Gerais. OBJECTIVE: The objective of this work was to provide a critical and situational overview of the physical and operational infrastructure of the transfusion services in the state. Method: This was an observational cross-sectional, evidence-based study covering 226 transfusion services; only 19 belong to the Hemominas Foundation and 207 are non-Hemominas transfusion services. The investigation involved the application of questionnaires and red cell panel tests. RESULTS: The results revealed considerable non-compliance with the national law and with the norms of Hemominas. These findings were obtained for the two groups studied; however the frequencies were higher among non-Hemominas transfusion services. CONCLUSION: The study provides information about the situation of the physical and operational infrastructure of transfusion services that may be used to help plan effective measures for improvement and serve as the basis for an evaluation of the impact of future interventions regarding the quality, reliability and safety of transfusions. As primordial factors, we propose compliance with the law, qualified personnel and investment in further qualifications, a review of training methods, and more rigorous inspection of transfusion services. As a suggestion, we propose the establishment of an External Quality Control Program in Immunohematology for the entire network of blood banks in the state and the adoption of the methods presented in this study as a tool to monitor transfusion service performance.

A alta morbimortalidade referida na doença falciforme (DF) levou-nos a estudar o perfil epidemiológico e respectivas intercorrências clínicas dos pacientes atendidos no Hemocentro Regional (HR) e Hospital de Clínicas da Universidade (HC-U), de 1998 a 2007. Estudo retrospectivo de 151 pacientes, avaliados quanto a: idade, gênero, cor da pele, procedência, diagnóstico, causa de atendimento no HR, causa e tempo de internação no HC-U e a causa e a idade em caso de óbito. Foi realizada análise estatística descritiva simples. A média de idade foi de 17,7 anos, 52,4% eram do gênero feminino, 58,2% procediam da cidade de Uberaba e em 92,2% dos prontuários não foram encontrados relatos sobre a cor da pele. A anemia falciforme representou 82,5% dos casos. Dos 910 atendimentos no HR e 589 internações no HC-U, a crise dolorosa afebril foi a causa mais frequente em ambas as instituições (61,9% e 25,3%, respectivamente). A idade média dos 11 óbitos foi de 33,5 anos, sendo apenas um em menor de 10 anos e a falência de múltiplos órgãos a causa mais frequente. O perfil epidemiológico mostra predomínio de crianças e adultos jovens, sexo feminino e genótipo SS. As taxas de internação no HC-U, de atendimento no HR e a baixa média de idade ao óbito confirmam a alta morbidade e mortalidade da DF. Contudo, o grande número de crianças sem intercorrências e/ou internações reflete a eficácia das medidas preventivas propiciadas pelo diagnóstico precoce implantado nos últimos 10 anos. The high morbidity-mortality rates in sickle cell disease (SCD) led us to study the epidemiological profile and respective clinical complications of patients seen at a Regional Blood Center (HR) and a University Clinical Hospital (HC-U) between 1998 and 2007. In a retrospective study, 151 patients were evaluated regarding age, gender, skin color, origin, diagnosis, reason of visit to HR or reason and length of stay in the HC-U, and cause and age in cases of death. Simple descriptive statistical analysis was performed. The mean age was 17.7 years, 52.4% of the patients were female, 58.2% were from the city and no information regarding skin color was available in 92.2% of the records. Sickle cell anemia was present in 82.5% of cases. The most frequent reason for the 910 visits to HR and 589 hospitalizations in HC-U were afebrile pain episodes (61.9% and 25.3%, respectively). The mean age of the 11 patients who died was 33.5 years with one patient being younger than 10 years old, and multiple organ failure was the most frequent cause. The epidemiological profile shows a predominance of children and young adults, women, and the SS genotype. The rates of hospitalization in HC-U and of visits to HR and the low mean age at death confirm the high morbidity and mortality related to SCD. However, a large number of children do not present with complications or require hospitalization which reflects the efficacy of preventive measures provided by the early diagnosis implemented over the last 10 years.

Candidatos a doação são submetidos a triagem clínica e sorológica para minimizar o risco de transmissão de doenças via transfusão. Uma de suas limitações é a janela imunológica, que possibilita a transfusão de sangue contaminado. O objetivo deste trabalho foi avaliar o índice de autoexclusão de acordo com idade, gênero, estado civil, cor e tipo de doação, as variações anuais de autoexcluídos e sua eficácia em evitar a transfusão de sangue contaminado. Os dados foram analisados através do teste qui-quadrado, odds ratio e regressão linear. De 1996 a 2006, o Hemocentro Regional de Uberaba (HRU) coletou 176.097 bolsas de sangue, das quais 2,72% foram desprezadas por autoexclusão, com significativo predomínio de homens, maiores de 29 anos, solteiros, não brancos e primeira doação (p

Available epidemiological data indicate that Chagas' disease, a zoonosis caused by the flagellate protozoan parasite T cruzi, is a very important medical and social problem in Latin America. More than 60% of T cruzi-infected individuals have migrated to urban areas, in both endemic and nonendemic countries. Thus, with the implementation and maintenance of regular vector control programs in some countries, allogeneic blood transfusions have been the main mechanism for the continuation of this endemy. The risk of infection after transfusion of a unit of T cruzi-infected blood product depends mainly on the amount of blood transfused, parasite concentration in the infected transfused blood unit, and the recipient's immunological status. Current strategies to prevent transfusion-associated Chagas' disease include the identification of T cruzi-infected blood donors by predonation questionnaire, serological tests for T cruzi antibodies, and the treatment of the blood collected with gentian violet. Because T cruzi infection is lifelong, and most infected persons are asymptomatic, the identification of high-risk blood donors by a predonation questionnaire is relevant in nonendemic countries but this strategy seems to be of limited usefulness for donor deferral in endemic areas. Because T cruzi antigens are shared by other parasites, the serological diagnosis of T cruzi infection is complex yielding both false-positive and false-negative results. Although sensitive, the tests currently available for the serodiagnosis of T cruzi infection lack specificity and a more specific, confirmatory test is still needed for the routine confirmation of T cruzi chronic infection. In areas of high endemicity or where serological screening is not available, the risk of T cruzi transmission by blood transfusion may be reduced by the addition of gentian violet to the collected blood. The use of gentian violet, alone or combined with ascorbic acid and light, effectively inactivate T cruzi present in donor blood; however, the long-term toxicity of this agent for blood recipients is still an open issue. In conclusion, the prevention of TA-CD is based on various strategies that are not mutually exclusive. Blood donor education, identification of putatively infectious blood donors by questionnaire or serological screening tests, and methods of parasite inactivation may significantly reduce the transmission of T cruzi by allogeneic blood transfusions.

aIn Brazil, the use of confirmatory or complementary tests isoptional for blood banks; however it is their responsibility tocontact donors with reagent tests and refer them to appropriateservices to confirm diagnosis and for treatment. In the UberabaBlood Bank (Hemominas), all donors with positive results forserological screening tests are requested, by mail, to return andrepeat the tests. In a study at this blood bank, it was noted that alarge percentage of donors with reagent serology for hepatitis Cin the first analysis (23.3%) did not return to the service for repeattests. Among the donors that did not return for repeat tests, weobserved a significantly higher number of first-time donors(p=0.0039), under 30-year-old (p=0.0327) and single individuals(p=0.0062) and those who do not live in the city (p=0.0465). Nodifferences were found comparing gender and skin color. As thecontact letter does not explain why donors are asked to return fortests, the donors are unaware of the results of examinations. Thus,if they donate blood in other blood banks, they really are infectedwith the hepatitis C virus and if failure in serologic screeningoccurs, there is a possibility of disease transmission if. So whatcan be done to increase the return rate for repeat tests? We believean urgent review of the methods used to contact these donors isnecessary, which will provide better and earlier therapy to infectedindividuals and help to reduce the risk of spread of infection. Rev.Bras. Hematol. Hemoter. 2009

A triagem sorológica de doadores de sangue com baixos índices de prevalência de infecção, como no caso da hepatite C (HCV), gera um percentual considerável de resultados falso-positivos e descarte de bolsas de hemocomponentes freqüentemente não infectados. O objetivo deste estudo foi pesquisar o perfil sorológico e, com base no teste confirmatório, a ocorrência de hepatite C nos doadores com sorologia positiva ou indeterminada do Hemocentro Regional de Uberaba (HRU). Os testes confirmatórios foram realizados por meio da detecção do RNA do HCV no plasma, utilizando-se o método RT-PCR qualitativa. Foram realizadas, no período de 1992 a 2005, 171.027 doações de sangue no HRU, sendo 24,3% de doadores iniciais e 75,7% de retorno. O índice de inaptidão para HCV foi de 0,3% (561 doações), sendo que 53,0% destas eram de doadores iniciais e 47,0% de retorno, com prevalências de 0,5% e 0,2%, respectivamente (p

Atualmente, um dos maiores problemas na triagem sorológica de doadores de sangue para doença de Chagas é a alta freqüência de reações indeterminadas, o que faz com que muitos indivíduos sadios sejam rotulados como portadores de uma doença grave. O presente trabalho tem o objetivo de analisar o comportamento sorológico para doença de Chagas dos doadores do Hemocentro Regional de Uberaba, MG e propor mecanismos para reduzir o índice de inaptidão sorológica para essa doença. Através de estudo retrospectivo, foi analisado o resultado sorológico de 79.729 amostras obtidas de doações de sangue realizadas neste Serviço entre janeiro de 2000 e dezembro de 2004. Os resultados foram analisados quanto às variáveis: tipo de doador (novo e de retorno), gênero e idade (inferior ou igual a 30 anos e superior a 30 anos). Para a análise estatística foram realizados os testes do Qui-Quadrado e de comparação de proporções (Z). A ocorrência de doações com sorologia não negativa para doença de Chagas entre doadores novos foi significativamente superior aos de retorno, com p< 0,0001. Quanto à idade, a proporção de positivos no grupo maior de 30 anos foi significativamente superior à do grupo com idade igual ou inferior a 30 anos (p< 0,0001). O elevado número de reações indeterminadas nesse Serviço está de acordo com estudos recentes, reforçando a necessidade da implementação de testes sorológicos 100% específicos ou de exames confirmatórios práticos e rápidos, passíveis de serem introduzidos nas rotinas dos serviços de hemoterapia, reduzindo o descarte desnecessário de bolsas de sangue. Currently one of the major problems in the serological selection of blood donors in respect to Chagas' disease is the high incidence of indeterminate reactions, making a large number of healthy individuals incorrectly diagnosed as seriously ill. This paper aims at evaluating the serological pattern of Chagas' disease of donors of the Uberaba Blood Center and also to propose mechanisms to reduce the rate of serological ineligibility due to suspicion of this disease. A retrospective study of the serological results of 79,729 samples of blood was carried out between January 2000 and December 2004. The results were analyzed according to the following variables: type of donor (first-time and multiple), gender and age (less than or equal to 30 or more than 30 years old). The statistical analysis was made using the chi-square test and a comparison of proportions (Z). Indeterminate results in respect to Chagas' disease among first-time donors were significantly higher than those of multiple donations with p < 0.0001. As for age, the proportion of positivity in the over 30-year-old group was significantly higher to that of the under or equal to 30-year-old group (p < 0.0001). The high number of indeterminate reactions at this center is in accordance with recent studies, highlighting the need of implementing serological tests with 100% specificity or the use of practical and fast confirmation tests to be routinely introduced in hemotherapy services, reducing the unnecessary rejection of blood bags.