Leucocyte depleted blood products 3.57.51 PM

Leucocyte depleted blood products 3.57.51 PM - Leucocyte...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Leucocyte depleted blood products. blood BCSH;Transfusion Medicine, 1998,8,59-71 Dr. Tariq Roshan 23rd March 2003 Objective Objective In which circumstances would you In recommend the use of leucocyte depleted blood products? blood To able to answer the question regarding To leucocyte depleted blood products. leucocyte For better understanding and to pave way for For provision of leucocyte depleted products by Department of Hematology in HUSM. Department Definition. Definition. Leucocyte depleted blood products must contain Leucocyte <0.5x109 leucocytes per unit red cells or adult <0.5x10 therapeutic dose of plateletts. therapeutic Practical aspects. To achieve residual count less than specified, process To should be completed with in 48 hours form collection of the donor unit. the Quality should be assured by monitoring the components Quality for 100% compliance. for Indications for the leucocyteIndications depleted blood components Recommended FNHTRs (Febrile non haemolytic transfusion reactions) To prevent recurrent FNHTRs Reducing graft rejection after haemopoietic cell transplantation. Prevention of transmission of viral infections by blood Prevention transfusion. transfusion. Fetal/Neonatal transfusions. Possible Platelet refractoriness Kidney transplants. Immunomodulation. Progression of HIV infection. Non indication TAGvHD The presence of leucocytes in blood components; responsible for many of complications associated with blood transfusion complications Patients receiving standard blood transfusion Patients receive large numbers of allogeneic leucocytes receive Confusing terms Leuco-poor Leuco-free Leuco-reduced Leuco-depleted is the accepted term There is confusion with the use of buffy coat depleted red cell There concentrate and pooled platelet concentrates (leucocyte levels are reduced but not to the level of leucocyte depleted components components Methods Methods Centrifugation Freeze / Thaw Filtration Most common used technique Aphaeresis with the use of filtration or without the use of Aphaeresis filtration filtration Filters 1st generation filters. Removes large clots and particulate debris 2nd generation filters. Designed to remove micro-aggregates of fibrin, platelets and leucocytes from red cell concentrates fibrin, 3rd generation filters. Designed specifically to remove free leucocytes. The reduction of leucocytes are three orders of magnitude magnitude Site of filtration Bedside during the transfusion Component processing laboratory Timing of leucocyte-depletion Timing With in short time after collection Advantage Leucocytes are removed before cytokines are removed Fragments of cell membranes and possible intracellular Fragments viruses removed viruses Cytokines are not released which results in FNHTR s HLA alloimmunization can occur with leucocyte fragments Laboratory filtration assures quality monitoring and also the Laboratory time of filtration time Filtration is done within 48 hours One school of thought favors processing of units after 6 One hours as it allows phagocytosis of any bacteria present hours Quality assurance Can be carried out prior to release of component by doing Can leucocyte counts leucocyte Flow cytometry Large volume microscopic chambers Labeling and storage Must be labeled as leucocyte depleted Shelf life and storage does not differ, if closed procedure Shelf used used FNHTRs FNHTRs Mechanism is different for both platelets and red cell Mechanism transfusion transfusion 6.8% after red cell transfusion 37.5% after platelet transfusion Associated with red cell transfusion HLA alloimmunization is the usual cause but not in case of red HLA cell transfusion cell Reaction do not always recurs FNHTR can be prevented by buffy coat depleted blood In cases of recurrence with buffy coat depleted blood, In leucodepleted blood is recommended. leucodepleted Used in patients dependent on long term transfusion support Associated with platelet transfusion Pyrogenic cytokines Usually not prevented by bedside filtration techniques as Usually cytokines released during storage at room temperature cytokines Recommendations for FNHTRs Recommendations For prevention of FNHTRs after red cells buffy For coat depleted red cell concentrates is recommended recommended For patients continue to have FNHTRs For despite buffy coat or bedside filtered red cell concentrates, leuco-depleted blood is recommended recommended For platelets leuco-depletion prior to storage For is recommended is Bedside filtration is not recommended Platelet refractoriness Platelet Common problem of failure to obtain satisfactory Common responses to platelet transfusions responses Immune mechanism Non-immune mechanism Immune cause is potentially more readily preventable HLA alloimmunization was only initiated by intact cells HLA expressing both HLA I & II classes expressing Platelets only express class I antigens This provides a rationale for the use of leucocyte-depleted blood HLA alloimmunization in non leucocyte depleted blood products HLA and pregnancy is 31% as compared to the patients receiving leucocyte depleted blood and no previous pregnancy leucocyte Pregnancy also presensitized the patients, reducing the dose of Pregnancy trasfused leucocytes for further immunization trasfused Irradiation of platelet concentrates with ultraviolet-B light, showed reduced alloimmunization showed Recommendation HLA alloimmunization reduces with the use of leucocytedepleted products Prevention of transmission of viral infections by blood transfusion infections CMV The use of CMV seronegative blood components has been The shown to reduce the incidence of CMV infection in at risk groups to a level of about 1-3% groups Transfusion transmitted infection is not completely prevented Transfusion may be due to Failure to detect low level antibodies Failure Loss of antibodies in previously infected donors Transfusion of components prepared from recently infected Transfusion donors donors Recommendations CMV seronegative pregnant women CMV seronegative recipients of allogeneic BMT AIDS Premature infants born to CMV seronegative women HTLV I & II Immunomodulation Immunomodulation Post operative infection Increase incidence on infection in the group receiving blood Increase transfusion after colorectal cancer as compared to the group receiving no transfusion receiving Incidence was same in patients receiving leucocyte-depleted Incidence blood as in non transfused group blood (other studies denies these findings) Cancer recurrence Results are conflicting In AML improved relapse free survival was found in one study In of patients receiving leucocyte-depleted blood of Recommendations There is insufficient evidence to recommend the routine use There of leucocyte-depleted blood components for surgical patients for the prevention of either post-operative infection or tumour recurrence recurrence Reactivation of latent infections Reactivation CMV / HIV Latent infection may become reactivated after an Latent immunological stimulus such as transfusion immunological Recommendation Leucocyte-depleted blood components may be Leucocyte-depleted used as an alternative to CMV-seronegative blood components to all pregnant women irrespective to their CMV status their In patients with HIV infection, there is insufficient In evidence of the reactivation of HIV evidence Avoidance of sensitization to transplantation antigens in potential transplant recipients antigens Sensitization by blood transfusion showed Sensitization to have adverse effects to Severe AA Increase risk of graft rejection if preceded by blood Increase transfusion transfusion Recommendatoins Patients with severe AA and potential haemopoietic Patients cell transplant recipients should receive leucocytecell depleted blood components Leucocyte-depleted blood components are not Leucocyte-depleted indicated for patients undergoing transplantation for haematological malignancies haematological Haemoglobinopathies Haemoglobinopathies Recommendations Buffy-coat depleted or bedside filtered red cell concentrates Buffy-coat are recommended for the prevention of FNHTRs are Leucocyte-depleted blood components can be used in Leucocyte-depleted potential candidates for haemopoietic stem cell transplantation to reduce the risk of graft rejection transplantation Solid tumors Recommendations Pre-transplant blood transfusion may confer some benefit to Pre-transplant renal transplant recipients, although some patients will become alloimmunized leading to difficulties in the selection of donor kidneys of HLA alloimmunizations should be prevented unless they are HLA part of pre-transplant immunosuppression protocol part Leucocyte-depleted blood is not recommended for liver and Leucocyte-depleted heart transplant heart Fetal / Neonatal transfusion Fetal Fetal / neonatal transfusion often consist Fetal of relatively fresh blood containing viable leucocytes leucocytes Increase risk of transmission of CMV Presence of viable lymphocytes may Presence cause TA-GvHD cause Recommendations Leucocyte-depleted blood components should be Leucocyte-depleted used for intra-utrine transfusion and for all transfusion to infants below 1 year of age transfusion ...
View Full Document

Ask a homework question - tutors are online