RESUMO
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% <6 vs. 2.56% >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.
RESUMO
ABSTRACT 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% <6 vs. 2.56% >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.
Assuntos
Transfusão de Sangue , Imunização , Transfusão de Eritrócitos , EritrócitosRESUMO
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.