Avaliação da eficácia do uso de filtros de leucócitos para retenção de L. (L.) infantum chagasi

Abstract

Leukocyte filters have been indicated in hemotherapy to prevent non-hemolytic febrile reactions, alloimmunization to human leukocyte antigens, chronic graft-versus-host disease, platelet refractoriness, immunomodulatory effects and to prevent transmission of cytomegalovirus (CMV ). The retention capacity has been described for other viruses, bacteria and parasites. This study aimed to verify the effectiveness of leukocyte filters for retention of Leishmania (Leishmania) infantum chagasi. Twenty aliquots of whole blood derived from blood bags with insufficient volume for transfusion use were used in the research, after serologic release by blood bank screening tests. The blood infection was performed at a ratio of 5 parasites / monocytes. The presence of parasites in the infected blood and maintained in Schneider medium culture for 14 days was confirmed by direct culture methods and analysis smears stained with May Grunwald - Giemsa on samples collected before and after blood filtration with filter Bio R01 plus Fresenius mark. Statistical analysis was performed using SPSS for Windows version 19.0; performed T tests, considered a significance level lower than 0.05 and checked inter observer agreement by Kappa. The average score of promastigotes in culture before filtration was 70,500 parasites / mL and after filtration was reduced to 19,500, a statistically significant reduction (p = 0.002). In the analysis of smears, rare parasites were identified after filtration and there was 80% agreement among observers. The study found leukocyte filters benefit for leishmania retention.