Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
2.
Hematol., Transfus. Cell Ther. (Impr.) ; 43(3): 287-294, July-Sept. 2021. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1346256

RESUMO

ABSTRACT Background: Transfusion of ABO-compatible non-identical platelets (PTLs), fresh plasma (FP) and red blood cells (RBCs) has been associated with increased morbidity and mortality of recipients. Trauma victims are frequently exposed to ABO non-identical products, given the need for emergency transfusions. Our goal was to evaluate the impact of the transfusion of ABO non-identical blood products on the severity and all-cause 30-day mortality of trauma patients. Methods: This was a retrospective single-center cohort, which included trauma patients who received emergency transfusions in the first 24 h of hospitalization. Patients were divided in two groups according to the use of <3 or ≥3 ABO non-identical blood products. The patient severity, measured by the Acute Physiology and Chronic Health Evaluation (APACHEII) score at ICU admission, and the 30-day mortality were compared between groups. Results: Two hundred and sixteen trauma patients were enrolled. Of these, 21.3% received ≥3 ABO non-identical blood products (RBCs, PLTs and FP or cryoprecipitate). The transfusion of ≥3 ABO non-identical blood products in the first 24 h of hospitalization was independently associated with a higher APACHEII score at ICU admission (OR = 3.28 and CI95% = 1.48-7.16). Transfusion of at least one unit of ABO non-identical PTLs was also associated with severity (OR = 10.89 and CI95% = 3.38-38.49). Transfusion of ABO non-identical blood products was not associated with a higher 30-day mortality in the studied cohort. Conclusion: The transfusion of ABO non-identical blood products and, especially, of ABO non-identical PLTs may be associated with the greater severity of trauma patients at ICU admission. The transfusion of ABO non-identical blood products in the trauma setting is not without risks.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Transfusão de Sangue , Sistema ABO de Grupos Sanguíneos , Ferimentos e Lesões , Plaquetas , Eritrócitos
4.
Transfusion ; 61(6): 1923-1931, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33687082

RESUMO

BACKGROUND: The genetic diversity of the RHCE gene locus has been explored in diverse populations of different racial backgrounds. Data referring to the diversity of RHCE encoding weakened expression of C, c, E, and e in multiethnic populations is still incomplete. METHODS: Samples from Brazilian blood donors presenting reduced expression of C, c, E, or e on gel method were selected for the study. All exons and flanking introns of RHCE were genotyped though direct Sanger sequencing for the included donors. RESULTS: Sixty-six donors were included: 23 with weak C, 22 with weak c, 6 with weak E, 14 with weak e, and 1 with weak c and E. Among the samples with weak C, the following altered RH*C were encountered: RHCE*CeMA (n = 3), RHCE*Ce941C (n = 1), and RHCE*CeVA (n = 1). RHD*D-CE(4-7)-D was detected in six cases, RHCE*CE was presumably present in five cases, and seven cases were unexplained. Two altered alleles underlay the weak c phenotype: RHCE*ceJAL (n = 20) and RHCE*ce340T (n = 2), and two altered RHCE justified weak e: RHCE*ceMO (n = 6) and RHCE*ceJAL (n = 8). Three variant RHCE were associated with weak E: RHCE*cEJU (n = 4), RHCE*cE382C (n = 1), and RHCE*cEIV (n = 1). The RHCE*cE905A justified one case of weak c and E. CONCLUSION: We describe the distribution of RHCE variants found in association with weak expression of C, c, E, and e in blood donors of multiethnic origin, which differs in comparison to that previously reported for people of African or Caucasian descent.


Assuntos
Doadores de Sangue , Sistema do Grupo Sanguíneo Rh-Hr/genética , Alelos , Brasil , Éxons , Frequência do Gene , Loci Gênicos , Variação Genética , Genótipo , Humanos , Íntrons
5.
Hematol Transfus Cell Ther ; 43(3): 287-294, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32798060

RESUMO

BACKGROUND: Transfusion of ABO-compatible non-identical platelets (PTLs), fresh plasma (FP) and red blood cells (RBCs) has been associated with increased morbidity and mortality of recipients. Trauma victims are frequently exposed to ABO non-identical products, given the need for emergency transfusions. Our goal was to evaluate the impact of the transfusion of ABO non-identical blood products on the severity and all-cause 30-day mortality of trauma patients. METHODS: This was a retrospective single-center cohort, which included trauma patients who received emergency transfusions in the first 24 h of hospitalization. Patients were divided in two groups according to the use of <3 or ≥3 ABO non-identical blood products. The patient severity, measured by the Acute Physiology and Chronic Health Evaluation (APACHEII) score at ICU admission, and the 30-day mortality were compared between groups. RESULTS: Two hundred and sixteen trauma patients were enrolled. Of these, 21.3% received ≥3 ABO non-identical blood products (RBCs, PLTs and FP or cryoprecipitate). The transfusion of ≥3 ABO non-identical blood products in the first 24 h of hospitalization was independently associated with a higher APACHEII score at ICU admission (OR = 3.28 and CI95% = 1.48-7.16). Transfusion of at least one unit of ABO non-identical PTLs was also associated with severity (OR = 10.89 and CI95% = 3.38-38.49). Transfusion of ABO non-identical blood products was not associated with a higher 30-day mortality in the studied cohort. CONCLUSION: The transfusion of ABO non-identical blood products and, especially, of ABO non-identical PLTs may be associated with the greater severity of trauma patients at ICU admission. The transfusion of ABO non-identical blood products in the trauma setting is not without risks.

6.
Transfus Apher Sci ; 59(6): 102882, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32741734

RESUMO

BACKGROUND: Digital droplet PCR (ddPCR) is a very sensitive high throughput genotyping methodology. To date, the use of ddPCR in immunohematology is restricted to fetal genotyping of red blood cell antigens. Our hypothesis is that this technology could be applied to screen for rare red blood cell genotypes, such as Di(b-). METHODS: Nucleic acid of 3168 donors was extracted for viral screening routine in pools of 6, which were converted into three types of 48-donor pools: control pools (only DI*B/*B samples), pools with varying amount of DI*A/*B samples (n = 1-5) and a pool with one rare DI*A/*A sample. Pools were genotyped using ddPCR to detect and quantify DI*A and DI*B alleles. RESULTS: DI*A allele was accurately detected in all pools containing Di(a + b+) samples and in the pool containing one Di(a + b-) sample. No copies were detected in the control pools (n = 60). The ratio between the number of DI*A and DI*B copies varied significantly between the pools and the triplicates. CONCLUSION: The proposed ddPCR assay was accurate in identifying the rare DI*A allele in large pools of donors and can be applied to screen for Di(b-) phenotype. The strategy can potentially be extended to search for other rare RBC phenotypes.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Reação em Cadeia da Polimerase Multiplex/métodos , Humanos
7.
Transfus Apher Sci ; 59(2): 102720, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31980333

RESUMO

INTRODUCTION: Patients with RH variants presenting antibodies directed to RH high frequency antigens or multiple RH antibodies might, in some occasions, be better served with RH genotype-matched units, requiring screening for RH variants among blood donors. To date, strategies to identify donors with RH variants were restricted to selecting individuals of African descent based on self-reported race, what can be inaccurate in racially mixed population. Our goal was to: 1) Screen for donors with RH variants in a mixed population using self-declared race and Rh phenotype as selection criteria; and 2) Verify if including the Duffy null genotype in the screening algorithm increases its effectiveness. METHODS: Brazilian donors were included if self-declared as black and phenotyped as R0r or R1r. All individuals were genotyped for RHCE exons 1, 5, 6 and 7 and for the FY*B c.-67 T > C polymorphism in order to determine the Duffy null genotype. RHD variants were searched for in cases of altered RHCE. RESULTS: Among 2500 blood donors, 217 fulfilled the inclusion criteria and were enrolled. Fifty-three (24.4 %) had a predicted clinically relevant Rh phenotype (partial antigens or lack of high frequency antigens). Twelve donors (5.5 %) had a predicted RhCE phenotype lacking either hrB or hrS. Most cases with predicted lack of high frequency antigens (66.7 %) occurred in donors with the Duffy null genotype. CONCLUSION: Selecting donors based on self-declared race, Rh phenotype and Duffy null genotype is feasible and effective in identifying RH variants lacking Rh high frequency antigens among racially mixed donors.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Feminino , Humanos , Masculino
8.
Vox Sang ; 114(6): 616-621, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31183870

RESUMO

BACKGROUND AND OBJECTIVES: Antibodies of unknown specificity (AUS) are frequently identified in the pre-transfusion testing. These antibodies can be insignificant or potentially cause post-transfusion haemolysis. Information about the prevalence of clinically relevant AUS is still lacking. Our aim was to predict the potential clinical relevance of AUS using the monocyte monolayer assay (MMA) and to identify the clinical and laboratorial determinants of AUS' significance. MATERIALS AND METHODS: Antibodies of unknown specificity identified at a single institution from 2015-2017 were evaluated through MMA. A monocyte index (MI) of more than 5% was predictive of potential post-transfusion haemolysis. RESULTS: Thirty-two patients with AUS were included in the study. Of the studied AUS, 37·5% (12/32) presented with a monocyte index (MI) more than 5%. In the group of significant AUS, 41·7% of the patients presented with sickle cell disease (SCD) and the AUS were associated with Rh antibodies in 75% of the cases. In the group of insignificant AUS, only 10% of the patients had SCD and the association with Rh antibodies was detected in 20% of the cases. The presence of Rh antibodies was independently associated with the AUS clinical relevance (P = 0·012). CONCLUSION: More than one-third of the AUS are potentially clinically relevant, and the association with Rh antibodies is predictive of AUS relevance. Services must honour AUS in the pre-transfusion process in order to ensure transfusion safety.


Assuntos
Anemia Falciforme , Isoanticorpos/sangue , Reação Transfusional/prevenção & controle , Especificidade de Anticorpos , Transfusão de Sangue , Humanos , Masculino , Monócitos , Reação Transfusional/diagnóstico , Reação Transfusional/etiologia
9.
Blood Cells Mol Dis ; 77: 23-28, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30939337

RESUMO

BACKGROUND: There is a significant inter-individual heterogeneity of Vel antigen expression which can lead to inaccuracies on Vel phenotyping of blood donors and, potentially, to hemolytic post-transfusion reactions. Our aim was to evaluate the impact of genetic variants in the SMIM1 intron 2 on the expression of Vel antigen among Brazilian blood donors harboring the c.64_80del17 deletion in heterozygosity. METHODS: Donors presenting the SMIM1 c.64_80del17 in heterozygosity were included in the study and subjected to SMIM1 intron 2 direct sequencing aiming to genotype the following polymorphisms: rs143702418, rs1181893, rs191041962, rs6673829, rs1175550 and rs9424296. RESULTS: SMIM1 intron 2 sequencing was performed on two hundred donors presenting one c.64_80del17 allele. The rs1175550 polymorphism significantly impacted on Vel antigen expression. Variations in the strength of agglutination on Vel phenotyping were also observed according to the rs6673829 genotype, but this difference did not persist with statistical relevance after multivariate analysis. CONCLUSION: The presence of the rs1175550A allele of SMIM1 is significantly and independently associated with a decrease in Vel antigen expression. Even though the population in Brazil is intensely mixed, the allele frequencies obtained in the current study were very similar to that reported for Europeans.


Assuntos
Variação Antigênica/genética , Doadores de Sangue , Regulação da Expressão Gênica , Variação Genética , Íntrons , Proteínas de Membrana/genética , Alelos , Brasil , Frequência do Gene , Estudos de Associação Genética , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Fenótipo , Deleção de Sequência
10.
Transfusion ; 59(5): 1827-1835, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30779172

RESUMO

BACKGROUND: As CD38 is expressed on red blood cells (RBCs), the plasma of patients on daratumumab (DARA) reacts with the panel cells of pretransfusion tests, masking underlying alloantibodies. The treatment of RBCs with dithiothreitol (DTT) is the most disseminated method to overcome DARA effect on immunohematological tests, but it hampers the identification of potentially harmful antibodies. Our goal was to validate a new strategy, the blockage monoclonal antibody protocol (BMAP), to mitigate the DARA interference on RBCs using anti-CD38 and antihuman globulin. METHODS: Samples of patients receiving DARA were included in the study. Sera were tested using both DTT- and BMAP-treated RBCs, which comprised three steps: 1) titration of monoclonal anti-CD38, 2) treatment of RBCs obtained from donors with anti-CD38, and 3) blockage of anti-CD38-adsorbed RBCs with antihuman globulin. RESULTS: Twenty patients were included in the study. Donor RBCs were treated with anti-CD38 and successfully blocked with antihuman globulin. In 19 patients, DARA-mediated agglutination was eliminated using both DTT- and BMAP-treated RBCs. In one patient, agglutination persisted when tested against the BMAP-treated RBCs, and alloantibodies were identified. Patient samples were mixed with commercial anti-D, -C, -e, -K, -Jka, -Kpb and tested against antigen-positive BMAP-treated RBCs, resulting in detection of these antibodies. CONCLUSION: This study validated a new strategy to minimize the interference of DARA on immunohematological tests. The protocol preserves the integrity of RBC antigens, permitting the detection of antibodies from all blood group systems. The BMAP has potential use in other situations where specific antibodies may interfere with pretransfusion screening.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Anticorpos Monoclonais/metabolismo , Isoanticorpos/metabolismo , Anticorpos Monoclonais/uso terapêutico , Ditiotreitol/uso terapêutico , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Imuno-Histoquímica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA