HLA-DRB1 molecules and the presentation of anchor peptides from RhD, RhCE, and KEL proteins.

BACKGROUND: Antigens from the Rh and Kell systems are recognized as the most immunogenic in clinical practice. This study evaluated the possible molecular mechanisms involved in the interaction of antigenic peptides with the DRB1 molecules, which help to explain the high frequency of anti-K and association of D + C antibodies in transfusion and incompatible pregnancy. STUDY DESIGN AND METHODS: We included 201 patients with antibodies against antigens from the Rh and Kell systems and compare them with 174,015 controls. HLA-DRB1 genotyping and in silico analysis were performed. The NetMHCIIpan software was used to identify RhD-, RhCE-, and KEL-derived anchor peptides that bind to DRB1 molecules. RESULTS: HLA-DRB1*15 is associated with an increased risk of D, C, E, and K alloimmunization, while the HLA-DRB1*01 and *12 alleles are overrepresented in patients with anti-C and anti-D, respectively. In silico analysis showed that three polymorphic points (60I, 68S, and 103S) common to C and D antigens can be presented by several DRB1 molecules, including DRB1*15:01. The DRB1*09:01 molecule, although not showing statistical significance, was able to interact strongly with almost all five anchor peptides from the sequence containing the polymorphic determinants of E antigen, except 217-WMFWPSVNS-225. CONCLUSION: The DRB1*15 molecule has specific physicochemical characteristics in residues 11P and 13R in the P4 pocket that can favor the response to various antigenic peptides. Anti-K alloimmunization is unrestricted for interaction with specific DRB1 molecules, which suggests that almost all individuals in our population have DRB1 molecules capable of binding to KEL-derived anchor peptides and produce anti-K when stimulated.

Autoimmune pancytopenia after liver transplantation: A case report.

INTRODUCTION: Autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP), and autoimmune neutropenia (AIN) are reported in the literature after liver, intestinal, heart, pancreas, and kidney transplants. We report a case of autoimmune pancytopenia (AIHA, AIN and ITP) 9 years after liver transplantation with confirmed erythrocyte and neutrophil auto-antibodies. CASE REPORT: A 49 years old man was admitted to our hospital presented with dysentery and fever, with history of liver transplantation in 2008. Laboratory evaluation demonstrated hemoglobin: 7.2 g/dL, granulocytes: 0.10 × 109/L and platelets: 15 × 109/mm³; indirect bilirubin: 3.62 mg/dL; lactate dehydrogenase: 603 U/L. Direct antiglobulin test revealed a monospecific anti-IgG plus C3 and the acid eluate was reactive to all panel red cells, consistent with an AIHA. Granulocyte immunofluorescence test (GIFT) and agglutination test (GAT) were reactive for granulocytes. Test with Luminex technology for human neutrophil antigen (HNA) antibody detection was strong reactive with beads expressing HNA-1a, -1b, -1c, -2, -4a and -5a antigens. HNA genotyping revealed the presence of the corresponding antigens, confirming the autoantibodies. Test with Luminex technology for human leucocyte antigen (HLA) antibody detection was negative. Monoclonal antibody immobilization of platelet antigens (MAIPA) assay was negative. Viral causes were excluded. The condition was compatible with clinical onset of autoimmune pancytopenia. Prednisone was administered at an initial dose of 1 mg/kg/day and immunosuppressive therapy was adjusted. This treatment resulted in rapid resolution of pancytopenia. CONCLUSION: Combined autoimmune pancytopenia (AIHA, AIN and ITP) is a rare condition that may occur after liver transplantation. Early recognition of this phenomenon permits appropriate treatment.

Molecular matching for patients with haematological diseases expressing altered RHD-RHCE genotypes.

BACKGROUND AND OBJECTIVES: The high homology and the inverted orientation of RHD and RHCE may give rise to non-functional and aberrant RH alleles. RH genotyping is used to screen RH matched donors to African descent patients. This study aimed to define a strategy for testing RHD and RHCE variants in blood donors to provide compatible units for transfusion of patients with haematological diseases. MATERIALS AND METHODS: Samples from 132 patients [101 Sickle cell disease (SCD), 14 myelodysplastic syndrome (MDS), 17 acute myelogenous leukaemia (AML)] and 198 Brazilian donors were studied. Major blood group alleles, RHD, RHCE alleles and RHD zygosity were determined by the blood-MLPA assay. Sequencing was performed to determine RHD and RHCE variant subtypes. A match was an RH genotype that did not encode Rh antigens absent in the patient, along with matching for ABO, MNS, KEL, FY, JK and DI antigens. RESULTS: Overall, 7·6% of blood donors and 17.4% of patients presented RH genotypes that predict expression of partial Rh antigens or lack of high prevalence Rh antigens. From 23 patients with clinically relevant RH genotypes, 15 had available matched donors. CONCLUSION: We report the presence of clinically relevant RH genotypes in SCD and in non-SCD patients. In our admixed population, many patients carry variant RHCE alleles in heterozygosity with normal RHCE alleles. Thus, our results suggest that donors could be selected based on the normal RH allele.

Antibodies to human neutrophil antigen HNA-3b implicated in cases of neonatal alloimmune neutropenia.

BACKGROUND: Neonatal alloimmune neutropenia results from maternal alloimmunization to human neutrophil antigens. The alloantibodies involved in neonatal alloimmune neutropenia are against human neutrophil antigens HNA-1a, HNA-1b, HNA-1c, HNA-1d, HNA-2, HNA-3a, HNA-4a, HNA-4b, and HNA-5a; however, to date, antibodies specific to HNA-3b have not been reported. STUDY DESIGN AND METHODS: Blood samples from 10,000 unselected neonates were analyzed, resulting in the selection of 88 neutropenic newborns (neutrophil count <1.5 × 109 /L) from 83 mothers (three pairs of twins and one triplet). HNA-3 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism to identify the cases of maternal-fetal HNA-3 incompatibility. Serologic studies for detecting maternal HNA-3 alloantibodies were performed with the granulocyte agglutination test, the white blood cell immunofluorescence test, and a LABScreen Multi-HNA Kit. RESULTS: Genotyping studies identified 13 of 88 (14.8%) instances of maternal-fetal HNA-3 incompatibility, with all mothers typed as HNA-3a/a and neonates typed as HNA-3a/b. Serologic studies revealed that five of 13 (38.5%) mothers carried anti-HNA-3b plus human leukocyte antigen antibodies and that three of 13 (23.1%) mothers had anti-HNA-3b without human leukocyte antigen antibodies. CONCLUSION: Here, we report the first three cases of neonatal alloimmune neutropenia associated with HNA-3b antibodies resulting in a neonatal alloimmune neutropenia incidence of one in 3333 live births.

Molecular study of Cw /Cx antigens and frequency of Rh phenotypes in southeast Brazilian blood donors.

BACKGROUND: The Cw (RH:8), Cx (RH:9), and MAR (RH:51) antigens are encoded by alleles at the Cc locus of the Rh system, where Cw and Cx are considered low-frequency antigens and antithetical to the high-frequency antigen MAR. The frequency of Cw (RH:8) is approximately 2% in Caucasians, 1% in Black people, 4% in Finns, and 9% in Latvians. The aim of this study was to determine the frequency of RhD+ phenotypes in a population of southeast Brazilian blood donors and to perform a molecular study to distinguish the RHCE*Ce.08.01 and RHCE*Ce.09 alleles, responsible for the Cw and Cx expressions, respectively. METHODS: We investigated 11,536 RhD+ Brazilian blood donors. All samples were phenotyped for D, C, c, E, e, and Cw . In the Cw + samples, a molecular analysis was performed to detect the nucleotide substitutions A122G and G106A, which determine the Cw and Cx antigens, respectively. RESULTS: Cw antigen was found in 110 (0.95%) samples in the following phenotypes: DCw e/dCw e (72/0.62%), DCw e/DCw e (30/0.26%), and DCw e/DCw E (8/0.07%). Among 110 Cw + samples, 108 showed the A122G nucleotide substitution associated with RHCE*Ce.08.01 allele and 2 samples the G106A substitution associated with the RHCE*Ce.09.01 allele. CONCLUSION: This study showed the prevalence of the RhD+ phenotype in the Brazilian population, and that through the molecular study, it was possible to differentiate the RHCE*Ce.08.01 and RHCE*Ce.09.01 alleles. The phenotype frequency was similar from Black people (1%) and different from Caucasians, Finns, and Latvians.

Molecular Basis of KELnull Phenotype in Brazilians.

BACKGROUND: KELnull (K0) persons can produce clinically significant anti-KEL5 antibody after transfusion and/or pregnancy, requiring K0 blood transfusion when indicated. 37 K0 alleles have been reported in studies over different populations, but none in Amerindian-Caucasian descendants from South America. The aim of this study was to identify the molecular basis of K0 phenotype in Brazilians. METHODS: We investigated three K0 samples from different Brazilian blood banks (Recife, Manaus, and Vila Velha) in women with anti-KEL5. KEL antigen typing was performed by serologic techniques, and the K0 status was confirmed by flow cytometry. PCR-RFLP and DNA sequencing of the KEL coding and exon-intron regions were also performed. RESULTS: RBCs of the 3 patients were phenotyped as KEL:-1,-2,-3,-4,-7. The 3 patients had the same KEL*02/02 genotype and were negative for KEL*02.03 and KEL*02.06 alleles. The Recife K0 patient was homozygous for IVS16 + 1g>a mutation (KEL*02N.31 allele). The flow cytometry with anti-KEL1, anti-KEL2, anti-KEL3, anti-KEL4, and anti-CD238 confirmed the K0 phenotype. In addition, we found the c.10423C>T mutation (KEL*02N.04 allele) in both the Manaus K0 and the Vila Velha K0 patients. CONCLUSION: This report represents the first study of K0 molecular basis performed in Amerindian-Caucasian descendants from South America.

HNA-3 gene frequencies in Brazilians and a new polymerase chain reaction-restriction fragment length polymorphism method for HNA-3a/3b genotyping.

BACKGROUND: HNA-3 antigens are the result of a rs2288904 single-nucleotide polymorphism (SNP) in the CTL2, and the HNA-3a and HNA-3b variants are encoded by a guanine and adenine at Nucleotide Position 461. Anti-HNA-3 are involved in severe transfusion-related acute lung injury reactions and in neonatal alloimmune neutropenia. Since the distribution of the HNA-3 system was unknown in South Americans, in this study we determined the frequency of the HNA-3 alleles in Brazilians. STUDY DESIGN AND METHODS: DNA of 500 blood donors, 120 Xikrin Amerindians, 74 Japanese individuals, and 124 African Brazilians were genotyped for rs2288904 by a polymerase chain reaction (PCR)-restriction fragment length polymorphism assay. The PCR product was digested with enzyme Taq(α) 1, specific to nucleotide guanine (HNA-3a). RESULTS: The results showed that the frequencies of the HNA-3a/HNA-3b alleles were 0.81/0.19 in blood donors, 1.00/0.00 in Amerindians, 0.63/0.37 in Japanese, and 0.85/0.15 in African Brazilians. All 81 individuals genotyped as HNA-3a/a did not present the SNP c.457T by molecular sequencing. CONCLUSION: The frequencies of HNA-3 genotypes in Brazilian blood donors is similar to that described in Caucasians; however, all Amerindians were HNA-3a/a, African Brazilians showed a lower frequency of HNA-3b/b, and Japanese had a higher prevalence of HNA-3b/b, suggesting that they may be at risk for developing anti-HNA-3a alloantibodies.

Frequency of the DI*A, DI*B and Band 3 Memphis polymorphism among distinct groups in Brazil.

INTRODUCTION: The Band 3 is a red blood cell protein that carries the Dia and Dib antigens from the Diego blood system. The SLC4A1 gene encodes Band 3; Band 3 Memphis is a polymorphism of normal Band 3 and has two variants, but only the variant II carries the Dia antigen. OBJECTIVES: Describe the frequencies of the DI*A and DI*B alleles and the Band 3 Memphis among blood donors, sickle cell disease (SCD) patients and Amazonian Indians. METHODS: A total of 427 blood samples were collected and separated into three groups: 206 unrelated blood donors, 90 patients with SCD and 131 Amazonian Indians. We performed DI*A/B, normal Band 3 and Band 3 Memphis genotyping, using the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). RESULTS: The frequency of the DI*A/DI*A genotype was 0.5% in blood donors and it was not found in other groups. The frequency of the DI*A/DI*B was higher in Amazonian Indians (33.6%) and the frequency of the DI*B/DI*B was highest in blood donors (92.2%). All 105 individuals tested were positive for the presence of normal Band 3 and of these individuals, only 5/105 (4.8%) presented the Band 3 Memphis mutation. CONCLUSION: We observed a higher frequency of the DI*B allele in blood donors and a low frequency of the DI*A/DI*A genotype in all groups studied. The Band 3 Memphis was found in a higher frequency in the blood donor group. Our findings highlight the importance of analyzing different population groups to gain a better understanding of the genetic association of blood group antigens.

BLOOD CELLS PROFILE IN UMBILICAL CORD OF LATE PRETERM AND TERM NEWBORNS.

OBJECTIVE: To describe the hematological profile in cord blood of late preterm and term newborns and compare blood indices according to sex, weight for gestational age and type of delivery. METHODS: Cross-sectional study with late preterm and term newborns in a second-level maternity. Multiple gestation, chorioamnionitis, maternal or fetal hemorrhage, suspected congenital infection, 5-minute Apgar <6, congenital malformations, and Rh hemolytic disease were excluded. Percentiles 3, 5,10, 25, 50, 75, 90, 95 and 97 of blood indices were calculated for both groups. RESULTS: 2,662 newborns were included in the sample, 51.1% males, 7.3% late preterms, 7.8% small for gestational age (SGA) and 81.2% adequate for gestational age (AGA). Mean gestational age was 35.6±1.9 and 39.3±1.0 weeks, respectively, for premature and term neonates. The erythrocytes indices and white blood cells increased from 34-36.9 to 37-41.9 weeks. Basophils and platelets remained constant during gestation. Premature neonates presented lower values ​​of all blood cells, except for lymphocytes and eosinophils. SGA neonates presented higher values ​​of hemoglobin, hematocrit and lower values of leukocytes, neutrophils, bands, segmented, eosinophils, monocytes and platelets. Male neonates presented similar values ​​of erythrocytes and hemoglobin and lower leukocytes, neutrophils, segmented and platelets. Neonates delivered by C-section had lower values ​​of red blood cells and platelets. Chronic or gestational hypertension induced lower number of platelets. CONCLUSIONS: Blood cells increased during gestation, except for platelets and basophils. SGA neonates had higher hemoglobin and hematocrit values and lower leukocytes. Number of platelets was smaller in male SGAs, born by C-section and whose mothers had hypertension.

Frequency of the DI*A, DI*B and Band 3 Memphis polymorphism among distinct groups in Brazil

ABSTRACT Introduction: The Band 3 is a red blood cell protein that carries the Dia and Dib antigens from the Diego blood system. The SLC4A1 gene encodes Band 3; Band 3 Memphis is a polymorphism of normal Band 3 and has two variants, but only the variant II carries the Dia antigen. Objectives: Describe the frequencies of the DI*A and DI*B alleles and the Band 3 Memphis among blood donors, sickle cell disease (SCD) patients and Amazonian Indians. Methods: A total of 427 blood samples were collected and separated into three groups: 206 unrelated blood donors, 90 patients with SCD and 131 Amazonian Indians. We performed DI*A/B, normal Band 3 and Band 3 Memphis genotyping, using the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). Results: The frequency of the DI*A/DI*A genotype was 0.5% in blood donors and it was not found in other groups. The frequency of the DI*A/DI*B was higher in Amazonian Indians (33.6%) and the frequency of the DI*B/DI*B was highest in blood donors (92.2%). All 105 individuals tested were positive for the presence of normal Band 3 and of these individuals, only 5/105 (4.8%) presented the Band 3 Memphis mutation. Conclusion: We observed a higher frequency of the DI*B allele in blood donors and a low frequency of the DI*A/DI*A genotype in all groups studied. The Band 3 Memphis was found in a higher frequency in the blood donor group. Our findings highlight the importance of analyzing different population groups to gain a better understanding of the genetic association of blood group antigens.

Anti-KEL7 (anti-Js(b)) alloimmunization diagnostic supported by molecular KEL*6,7 typing in a pregnant woman with previous intrauterine deaths.

Anti-KEL7 (anti-Js(b)) is a rare antibody that has been related to haemolytic transfusion reactions and HDN. We report a case of anti-KEL7 alloimmunization detected in a pregnant woman who had an obstetric previous history of four miscarriages and one stillborn. Employing classical immunohematological techniques, we studied the propositus and her available relatives. Due to the unavailability of commercial anti-KEL6 and anti-KEL7 reagents, we used a KEL*6,7 genotyping method as an alternative tool to contribute with the identification of the alloantibody origin. The results of KEL genotyping showed that the propositus was KEL*6/6 homozygous, while her second partner was KEL*7/7 homozygous.

Frequência das reações transfusionais imediatas ocorridas em hospital de ensino em São Paulo, Brasil / The frequency of immediate transfusions reactions occurred in a teaching hospital from Sao Paulo, Brazil / La frecuencia de las Reacciones transfusionales inmediatas ocurridas en hospital de enseñanza en Sao Paulo, Brasil

Objetivo: descrever a ocorrência das reações transfusionais imediatas recebidas na Gerência de Risco do Hospital São Paulo. Metodologia: foi realizado um estudo transversal retrospectivo, com analises das fichas de notificação de Reações Transfusionais no período de maio de 2002 a dezembro de 2016 que foram inseridas no SNH. Resultados: foram analisadas 1548 fichas de RT, em sua quase totalidade reações imediatas, associadas ao Concentrado de Hemácias (72,5%). A mais comum foi a Reação Febril Não Hemolítica leve, sendo entre as graves e moderadas a Reação Alérgica. Os sinais e sintomas mais notificados foram a hipertermia, a sudorese, calafrios e lesões em derme. Não foram observadas diferenças entre sexo e idade, 90,8% das Reações Transfusionais ocorreram em pacientes com Fator Rh(+). Conclusão: o estudo permitiu uma melhor avalição e compreensão das reações transfusionais o que permite maior qualidade no ciclo do sangue e uma maior segurança dos pacientes submetidos a terapia transfusional.

Objective: to describe the occurrence of the immediate transfusion reactions received at the Risk Management of Hospital São Paulo. Methodology: a cross-sectional retrospective study was carried out, with analyzes of the ATR (Adverse Transfusional Reactions) in the period from May 2002 to December 2016 which were inserted in the National Haemovigilance System (SNH). Results: it were analyzed 1548 ATR records, most of which were immediate reactions, associated with the Red blood cells Concentrate (72,5%). The most common slight reaction was FNHTR (Febrile non-hemolytic transfusion reaction), and being between severe and moderate reactions, The Allergic reaction. The most commonly reported signs and symptoms were hyperthermia, sweating, chills and skins lesions. No differences were observed between gender and age, 90.8% of ATR occurred in patients with RhD positive blood group. Conclusion: the study allowed a better evaluation and understanding of the transfusion reactions which allowed higher quality in the blood cycle and increased safety of patients undergoing transfusion therapy.

Objetivo: describir la ocurrencia de las reacciones transfusionales inmediatas recibidas en la Gestión de Riesgo del Hospital São Paulo. Metodología: se realizó un estudio transversal retrospectivo, con análisis de las fichas de notificación de Reacciones Transfusionales en el período de mayo de 2002 a diciembre de 2016 que fueron introducidas en el SNH. Resultados: se analizaron 1548 fichas de RT inmediatas, asociadas al Concentrado de Hemácias (72,5%). La más común fue la Reacción Febril no Hemolítica leve, siendo la reacción alérgica entre las graves y moderadas. Los signos y síntomas más notificados fueron la fiebre, la sudoración, escalofríos y lesiones en dermis. No se observaron diferencias entre sexo y edad, el 90,8% de las Reacciones Transfusionales ocurrieron en pacientes con Factor Rh(+). Conclusión: el estudio permitió una mejor evaluación y comprensión de las reacciones transfusionales, lo que permite mayor calidad en el ciclo de la sangre y una mayor seguridad de los pacientes sometidos a terapia transfusional.

Blood cells profile in umbilical cord of late preterm and term newborns / Perfil de hemograma em sangue de cordão umbilical de recém-nascidos pré-termo tardio e a termo

ABSTRACT Objective: To describe the hematological profile in cord blood of late preterm and term newborns and compare blood indices according to sex, weight for gestational age and type of delivery. Methods: Cross-sectional study with late preterm and term newborns in a second-level maternity. Multiple gestation, chorioamnionitis, maternal or fetal hemorrhage, suspected congenital infection, 5-minute Apgar <6, congenital malformations, and Rh hemolytic disease were excluded. Percentiles 3, 5,10, 25, 50, 75, 90, 95 and 97 of blood indices were calculated for both groups. Results: 2,662 newborns were included in the sample, 51.1% males, 7.3% late preterms, 7.8% small for gestational age (SGA) and 81.2% adequate for gestational age (AGA). Mean gestational age was 35.6±1.9 and 39.3±1.0 weeks, respectively, for premature and term neonates. The erythrocytes indices and white blood cells increased from 34-36.9 to 37-41.9 weeks. Basophils and platelets remained constant during gestation. Premature neonates presented lower values ​​of all blood cells, except for lymphocytes and eosinophils. SGA neonates presented higher values ​​of hemoglobin, hematocrit and lower values of leukocytes, neutrophils, bands, segmented, eosinophils, monocytes and platelets. Male neonates presented similar values ​​of erythrocytes and hemoglobin and lower leukocytes, neutrophils, segmented and platelets. Neonates delivered by C-section had lower values ​​of red blood cells and platelets. Chronic or gestational hypertension induced lower number of platelets. Conclusions: Blood cells increased during gestation, except for platelets and basophils. SGA neonates had higher hemoglobin and hematocrit values and lower leukocytes. Number of platelets was smaller in male SGAs, born by C-section and whose mothers had hypertension.

RESUMO Objetivo: Descrever o perfil hematológico em sangue de cordão de recém-nascidos pré-termo tardio e a termo e comparar parâmetros hematimétricos segundo sexo, adequação peso idade gestacional e tipo de parto. Métodos: Estudo transversal com recém-nascidos pré-termo tardio e a termo, em maternidade de nível secundário. Excluíram-se gestação múltipla, corioamnionite, hemorragia materna ou fetal, suspeita de infecção congênita, Apgar no 5o minuto <6, malformações congênitas e doença hemolítica Rh. Calcularam-se os percentis 3, 5, 10, 25, 50, 75, 90, 95 e 97 dos parâmetros hematológicos. Resultados: Incluíram-se 2.662 recém-nascidos, 51,1% do sexo masculino, 7,3% prematuros tardios, 7,8% pequenos para a idade gestacional e 81,2% adequados. A idade gestacional foi 35,6±1,9 e 39,3±1,0 semanas, respectivamente, nos prematuros e termos. As séries vermelha e branca aumentaram de 34-36,9 para 37-41,9 semanas, exceto basófilos e plaquetas, que permaneceram constantes. Os prematuros apresentaram menores médias nas séries vermelha, plaquetária e branca, com exceção de linfócitos e eosinófilos. Recém-nascidos pequenos para a idade gestacional apresentaram maiores valores de hemoglobina e hematócrito e menores de leucócitos, neutrófilos, bastonetes segmentados, eosinófilos, monócitos e plaquetas. Recém-nascidos masculinos apresentaram taxas semelhantes de hemoglobina e hematócrito e menores de leucócitos, neutrófilos, segmentados e plaquetas. Na cesárea, as células vermelhas e as plaquetas foram menores que no parto vaginal. O número de plaquetas foi menor na hipertensão crônica ou gestacional. Conclusões: As células sanguíneas aumentaram durante a gestação, exceto plaquetas e basófilos. Recém-nascidos pequenos para a idade gestacional apresentaram maiores taxas de hemoglobina e hematócrito e menores de células brancas. O número de plaquetas foi menor no recém-nascido pequeno para a idade gestacional, masculino, nascido por cesárea e de mãe hipertensa.

Reduction of exposure to blood donors in preterm infants submitted to red blood cell transfusions using pediatric satellite packs.

OBJECTIVE: In preterm newborn infants transfused with erythrocytes stored up to 28 days, to compare the reduction of blood donor exposure in two groups of infants classified according to birth weight. METHODS: A prospective study was conducted with preterm infants with birth weight <1000 g (Group 1) and 1000-1499 g (Group 2), born between April, 2008 and December, 2009. Neonates submitted to exchange transfusions, emergency erythrocyte transfusion, or those who died in the first 24 hours of life were excluded. Transfusions were indicated according to the local guideline using pediatric transfusion satellite bags. Demographic and clinical data, besides number of transfusions and donors were assessed. . Logistic regression analysis was performed to determine factors associated with multiple transfusions. RESULTS: 30 and 48 neonates were included in Groups 1 and 2, respectively. The percentage of newborns with more than one erythrocyte transfusion (90 versus 11%), the median number of transfusions (3 versus 1) and the median of blood donors (2 versus 1) were higher in Group 1 (p<0.001), compared to Group 2. Among those with multiple transfusions, 14 (82%) and one (50%) presented 50% reduction in the number of blood donors, respectively in Groups 1 and 2. Factors associated with multiple transfusions were: birth weight <1000 g (OR 11.91; 95%CI 2.14-66.27) and presence of arterial umbilical catheter (OR 8.59; 95%CI 1.94-38.13), adjusted for confounders. CONCLUSIONS: The efficacy of pediatrics satellites bags on blood donor reduction was higher in preterm infants with birth weight <1000 g.

Reduction of exposure to blood donors in preterm infants submitted to red blood cell transfusions using pediatric satellite packs / Reduccion de la exposicion a donantes de sangre en prematuros sometidos a transfusiones de hematies con uso de bolsas de transferencia pediatrica / Reducao da exposicao a doadores de sangue em prematuros submetidos a transfusoes de hemaciascom uso de bolsas de transferencia pediatricas

OBJECTIVE: In preterm newborn infants transfused with erythrocytes stored up to 28 days, to compare the reduction of blood donor exposure in two groups of infants classified according to birth weight. METHODS: A prospective study was conducted with preterm infants with birth weight <1000g (Group 1) and 1000-1499g (Group 2), born between April, 2008 and December, 2009. Neonates submitted to exchange transfusions, emergency erythrocyte transfusion, or those who died in the first 24 hours of life were excluded. Transfusions were indicated according to the local guideline using pediatric transfusion satellite bags. Demographic and clinical data, besides number of transfusions and donors were assessed. . Logistic regression analysis was performed to determine factors associated with multiple transfusions. RESULTS: 30 and 48 neonates were included in Groups 1 and 2, respectively. The percentage of newborns with more than one erythrocyte transfusion (90 versus 11%), the median number of transfusions (3 versus 1) and the median of blood donors (2 versus 1) were higher in Group 1 (p<0.001), compared to Group 2. Among those with multiple transfusions, 14 (82%) and one (50%) presented 50% reduction in the number of blood donors, respectively in Groups 1 and 2. Factors associated with multiple transfusions were: birth weight <1000g (OR 11.91; 95%CI 2.14-66.27) and presence of arterial umbilical catheter (OR 8.59; 95%CI 1.94-38.13), adjusted for confounders. CONCLUSIONS: The efficacy of pediatrics satellites bags on blood donor reduction was higher in preterm infants with birth weight <1000g. .

OBJETIVO En prematuros transfundidos con hematíes preservados por hasta 28 días, comparar la reducción de exposición a donantes en dos grupos de pacientes, según el peso al nacer. MÉTODO Se trata de un estudio prospectivo con prematuros con peso al nacer <1000g (Grupo 1) y de 1000-1499g (Grupo 2), nacidos entre abr/2008 a dic/2009. Se excluyeron recién-nacidos sometidos a exsanguineotransfusión, transfusión de emergencia u óbito antes de 24 horas de vida. Las transfusiones fueron indicadas según la rutina del servicio, utilizando bolsas de transferencia pediátrica. Se analizaron datos demográficos, clínicos y número de transfusiones y donantes. Variables categóricas fueron comparadas por la prueba de chi-cuadrado y numéricas por la prueba t o Mann-Whitney. Se utilizó regresión logística para análisis de factores asociados a las múltiples transfusiones. RESULTADOS: Se incluyeron 30 prematuros en el Grupo 1 y 48 en el Grupo 2. El porcentaje de prematuros que recibió más de una transfusión de hematíes (89,5 versus 10,5%), la mediana del número de transfusiones (3 versus 1) y la mediana de donantes (2 versus 1) fue mayor en el Grupo 1, comparado al Grupo 2 (p<0,001). Entre aquellos con transfusiones múltiples, 14 (82,4%) y 1 (50,0%) prematuros presentaron reducción de 50% de donantes respectivamente en los Grupos 1 y 2. Los factores asociados a múltiples transfusiones fueron peso al nacer <1000g (OR 11,91; IC95% 2,14-66,27) y presencia de catéter arterial umbilical (8,59; 1,94-38,13), controlados para variables de confusión. CONCLUSIONES La eficacia de las bolsas de transferencia pediátricas para reducir la exposición a donantes de sangre fue mayor en prematuros con peso al nacer <1000g. .

OBJETIVO Em prematuros transfundidos com hemácias preservadas por até 28 dias, comparar a redução de exposição a doadores em dois grupos de pacientes, de acordo com o peso ao nascer. MÉTODOS Estudo prospectivo de prematuros com peso ao nascer <1000g (Grupo 1) e de 1000-1499g (Grupo 2), nascidos entre abril de 2008 e dezembro de 2009. Excluíram-se os recém-nascidos submetidos a exsanguineotransfusão, transfusão de emergência ou óbito antes de 24 horas de vida. As transfusões foram indicadas conforme rotina do serviço, utilizando-se bolsas de transferência pediátricas. Analisaram-se dados demográficos, clínicos e número de transfusões e doadores. Utilizou-se regressão logística para análise de fatores associados às múltiplas transfusões. RESULTADOS Incluíram-se 30 prematuros no Grupo 1 e 48 no Grupo 2. A porcentagem de prematuros que receberam mais de uma transfusão de hemácias (90 versus 11%), a mediana do número de transfusões (3 versus 1) e mediana de doadores (2 versus 1) foram maiores no Grupo 1, comparado ao Grupo 2 (p<0,001). Entre aqueles com transfusões múltiplas, 14 (82%) e um (50%) prematuros apresentaram redução de 50% de doadores respectivamente nos Grupos 1 e 2. Os fatores associados a múltiplas transfusões foram peso ao nascer <1000g (OR 11,91; IC95% 2,14-66,27) e presença de cateter arterial umbilical (OR 8,59; IC95% 1,94-38,13), controlados para variáveis de confusão. CONCLUSÕES A eficácia das bolsas de transferência pediátricas para reduzir a exposição a doadores de sangue foi maior em prematuros com peso ao nascer <1000g. .

Gene frequencies of the HNA-4a and -5a neutrophil antigens in Brazilian persons and a new polymerase chain reaction-restriction fragment length polymorphism method for HNA-5a genotyping.

BACKGROUND: The HNA-4a (Mart) and HNA-5a (Ond) antigens are polymorphic variants of alpha(M) (CD11b) and alpha(L) (CD11a) subunits of the beta(2)-integrin, and are associated with single nucleotide polymorphisms (SNP) leading to amino acid dimorphisms. HNA-4a has been linked to alloimmune neonatal neutropenia, but the HNA-5a clinical significance is unclear. STUDY DESIGN AND METHODS: Using a polymerase chain reaction (PCR) with sequence-specific primers, the frequency of HNA-4a among 121 Brazilian blood donors and 114 Amazon Indians was determined. A PCR-restriction fragment length polymorphism (RFLP) method for HNA-5a genotyping was developed, and the gene frequencies of this antigen were determined among 123 blood donors and 114 Indians. To validate the genotyping method, the amplified DNA from six previously obtained samples (two of each genotype) was sequenced. RESULTS: The HNA-4a (+/+), HNA-4a (+/-), and HNA-4a (-/-) genotype frequencies of blood donors (0.686, 0.273, 0.041) and Indians (1.000, 0.000, 0.000) were different (p < 0.01). The frequencies of HNA-5a (+/+), HNA-5a (+/-), and HNA-5a (-/-) genotypes among blood donors (0.512, 0.399, 0.089) and Indians (0.746, 0.219, 0.035) also differed (p < 0.01). Sequencing demonstrated concordance with PCR-RFLP genotyping in all six evaluated samples. CONCLUSION: Comparing to another populations, Brazilians present a higher frequency of HNA-4a-negative allele, suggesting that Brazilians would be more susceptible to HNA-4a alloimmunization. Moreover, the distribution of the HNA-4 alleles observed in Amazon Indians is quite similar to that reported among Koreans. Besides that, a new effective and efficient HNA-5a genotyping technique is now available for population studies.