Guidelines on the clinical use of leucocyte-depleted blood components. British Committee for Standards in Haematology, Blood Transfusion Task Force.

Definition: Leucocyte-depleted blood components must contain < 5 × 10 leucocytes per unit (red cells) or adult therapeutic dose (platelets). Practical aspects: To achieve residual leucocyte counts of < 5 × 10, leucocyte-depletion should be carried out under controlled conditions, ideally within 48 h from the collection of the donor unit. The preparation of leucocyte-depleted blood components should be subject to a quality monitoring programme designed to assure 100% compliance. Indications for leucocyte-depleted blood components RECOMMENDED Febrile nonhaemolytic transfusion reactions (FNHTRs) 1 To prevent recurrent FNHTRs after red-cell transfusions, buffy coat-depleted red-cell concentrates should be used, if they are available, or alternatively red-cell concentrates filtered at the bedside. 2 If FNHTRs continue despite these measures, leucocytedepleted red-cell concentrates should be used. 3 To prevent FNHTRs in patients likely to be dependent on long-term red-cell support, the use of buffy-coatdepleted or bedside filtered red-cell concentrates should be considered from the outset of transfusion support. 4 The routine use of pooled platelets derived from buffy coats is associated with a low incidence of FNHTRs. The use of platelet concentrates leucocyte-depleted prior to storage is recommended for patients with reactions despite the use of such components. Bedside filtration of platelet concentrates is not recommended for the prevention of FNHTRs associated with platelet transfusions. Reducing graft rejection after haemopoietic cell transplantation: Patients with severe aplastic anaemia who are potential haemopoietic cell transplant recipients should receive leucocyte-depleted blood components from the beginning of transfusion support. The same might apply to patients with haemoglobinopathies, but more evidence is required before a definite recommendation can be made. Prevention of transmission of viral infections by blood transfusion: Leucocyte-depletion of blood components is an effective alternative to the use of CMVseronegative blood components for the prevention of transfusion-transmitted CMV infection to at-risk patients. Fetal/neonatal transfusions: Leucocyte-depleted blood components should be used for intrauterine transfusions and for all transfusions to infants below 1 year of age. POSSIBLE Platelet refractoriness: There is currently no convincing evidence that routine leucocyte-depletion of blood components produces clinical benefits for patients receiving multiple platelet transfusions, although HLA alloimmunization and platelet refractoriness are reduced. Kidney transplants: Pretransplant blood transfusion may confer some benefit to renal transplant recipients, although some patients will become alloimmunized leading to difficulties in the selection of donor kidneys. Consideration should be given to the leucocyte-depletion of transfusions to renal transplant patients to prevent HLA alloimmunization unless they are part of a deliberate pretransplant immunosuppression protocol. Immunomodulation: There is insufficient evidence to recommend the routine use of leucocyte-depleted blood components for surgical patients for the prevention of either post-operative infection or tumour recurrence. Progression of HIV infection: There is insufficient evidence to recommend the use of leucocyte-depleted blood components for reducing the progression of HIV infection. Transfusion Medicine, 1998, 8, 59–71