1.1 Background
Cellular blood components are irradiated to prevent transfusion-associated Graft-vs-host disease (TA-GVHD). TA-GVHD is a potential complication of transfusion of any blood component containing viable T lymphocytes where there is a degree of disparity in histocompatibility antigens between donor and patient.
The risks of TA-GVHD are highest in recipients with immunodeficiency or immunosuppression, although TA-GVHD has not been described in patients infected with the human immunodeficiency virus. In immunocompetent individuals, sharing of an HLA haplotype with the donor appears to be a major contributory factor.
These cellular blood components are irradiated by either X-ray or irradiation and are identified by an approved overstick label which should include the date of irradiation and any reduction in shelf life. The effectiveness of this process must be checked by examining the RAD-SURE label on each pack - the central opaque portion will have changed from 'NOT IRRADIATED' to 'IRRADIATED'.
Recommendation. The minimum dose achieved in the irradiation volume should be 25Gy, with no part receiving more than 50Gy (Grade 1 recommendatin; level B evidence)
1.2 Indications for Irradiated Cellular Products
1.2.1 Paediatric Practice
1.2.1.1 Intrauterine (IUT) and neonatal exchange transfusion (ET)
All blood for intrauterine transfusion (IUT) should be irradiated. It is essential to irradiate blood for neonatal exchange transfusion (ET) if there has been a previous IUT or if the donation comes from a first- or second-degree relative. For other neonatal ET cases, irradiation is recommended provided this does not unduly delay transfusion. For IUT and ET, blood should be transfused within 24 hours of irradiation and, in any case, by 5 days or less from collection.
1.2.1.2 Top-up transfusion
It is not necessary to irradiate red cells for routine ‘top-up’transfusions of premature or term infants unless either there has been a previous IUT, in which case irradiated compounds should be administered until 6 months after the expected delivery date(40 weeks gestation), or the donation has come from a first-or second degree relative (2C)
1.2.1.3 Platelet transfusions
Platelets transfused in utero to treat alloimmune thrombocytopenia should be irradiated and any subsequent red cell or platelet transfusions irradiated until 6 months after the expected date of delivery (40 weeks gestation) There is no need to irradiate other platelet transfusions for pre –term or term infants, unless they have been donated by first- or second degree relatives
1.2.1.4 Granulocyte transfusions
All granulocyte transfusions should be irradiated for recipients of any age, and transfused as soon as possible after irradiation.
1.2.1.5 Congenital immunodeficiencies in infants and children
All severe T lymphocyte immunodeficiency syndromes should be considered as indications for irradiation of cellular blood components. Once a diagnosis of immunodeficiency has been suspected, irradiated components should be given while further diagnostic tests are undertaken. A clinical immunologist should be consulted for advice in cases where there is uncertainty.
1.2.1.6 Acquired immunodeficiency states in childhood
There is no indication for routine irradiation of cellular blood components for infants or children who are suffering from a common viral infection, who are HIV positive, or who have AIDS. However, this should be kept under review. There is also no indication for routine irradiation of cellular blood components for adults who are HIV positive or who have AIDS.
1.2.1.7 Cardiac surgery in neonates and infants
There is no need to irradiate red cells or platelets for infants undergoing cardiac surgery unless clinical or laboratory features suggest a coexisting T lymphocyte immunodeficiency syndrome
1.2.2 Haematology and Stem Cell Transplant Patients – Children and Adults
1.2.2.1 Acute leukemia
It is not necessary to irradiate red cells or platelets for adults or children with acute leukemia, except for HLA-matched platelets or donations from first- or second-degree relatives, unless patients have received purine analogues (see 1.2.3.1).
1.2.2.2 Allogeneic stem cell transplantation
All recipients of allogeneic haemopoietic stem cell transplantation (SCT) must receive irradiated blood components from the time of initiation of conditioning chemoradiotherapy
Irradiated components should be continued while the patient continues to receive graft-versus- host disease (GvHD) prophylaxis, i.e usually for 6 months post transplant, or until lymphocytes are>1 x 109 / l If chronic GvHD is present or if continued immunosuppressive treatment is required, irradiated blood components should be given indefinitely.
Allogeneic blood transfused to bone marrow and peripheral blood stem cell donors 7 days prior to or during the harvest should also be irradiated
1.2.2.3 Autologous bone marrow/peripheral blood stem cell recipients
Patients undergoing bone marrow or peripheral blood stem cell ‘harvesting’ for future autologous re-infusion should receive irradiated cellular blood components during and for 7 days before the bone marrow/ stem cell harvest to prevent collection of viable allogeneic T lymphocytes which can potentially withstand cryopreservation
All patients undergoing autologous bone marrow transplant or peripheral blood stem cell transplant should receive irradiated cellular blood components from initiation of conditioning chemo/radiotherapy until 3 months post- transplant (6 months if total body irradiation was used in conditioning)
1.2.3 Other Patient Groups
1.2.3.1 Purine analogues
Patients treated with purine analogue drugs (Fludarabine,Cladribine and deoxycoformycin) should receive irradiated blood components indefinitely.
The situation with other purine analogues such as Bendamustine and clofarabine is unclear, but use of irradiated blood components is recommended as these agents have a similar mode of action
1.2.3.2 Biological Agents
Irradiated blood components should be used after alemtuzumab (anti- CD52) therapy. Their use after rituximab(anti -CD20) is not recommended at this time. As new potent immunosuppressive drugs and biological agents are introduced into practice there is a need for a regular review of these recommendations.
1.2.3.3 Hodgkin's disease
All adults and children with Hodgkin’s lymphoma at any stage of the disease should have irradiated red cells and platelets for life.
1.2.3.4 Acquired immunodeficiency
It is not necessary to irradiate blood components for patients undergoing routine surgery, those with solid tumours, HIV infection, autoimmune diseases or after solid organ transplantation (unless alemtuzumab) (anti –CD52) has been used in the conditioning regime). The effects of new regimes of chemo – and immunotherapy entering clinical practice must continue to be monitored (Grade 2 recommendation: level C evidence)
1.2.3.5 Aplastic anaemia.
In view of the recent switch from horse anti- thymocyte globulin (ATG) to the more immunosuppressive rabbit ATG, we now recommend use of irradiated blood components for aplastic anaemia patients receiving immunosuppressive therapy with ATG( and / or alemtuzumab)
Irradiaated components are recommended for all patients receiving immunosuppressive therapy with anti- thymocyte globulin(ATG)
We cannot make a firm recommendation as to how long irradiated products should continue to be used after ATG administration but the 2009 BCSH guidelines recommend continuing at least until the lymphocyte count>1x109/l.
1.2.3.6 Donations from family members and HLA-selected donors
All transfusions from first- or second-degree relatives should be irradiated, even if the patient is immunocompetent. Likewise, all HLA-matched components should be irradiated, even if the patient is immunocompetent.
1.2.4 Which components should be irradiated
For at-risk patients, all red cell, platelet and granulocyte transfusions should be irradiated, except cryopreserved red cells after deglycerolization. It is not necessary to irradiate fresh frozen plasma, cryoprecipitate or fractionated plasma products.
Red cells may be irradiated at any time up to 14 days after collection, and thereafter stored for a further 14 days from irradiation. Where the patient is at particular risk from hyperkalaemia, e.g. intrauterine or neonatal exchange transfusion, it is recommended that red cells be transfused within 24 hrs of irradiation or cells are washed.
Platelets can be irradiated at any stage during storage and can thereafter be stored up to their normal shelf life after collection..
Granulocytes for all recipients should be irradiated before issue, and thereafter transfused with minimum delay.
Irradiated components not used for the intended recipient can be safely returned to stock to be used for recipients who do not require irradiated components. The reduction in shelf life must be observed.
All irradiated units should be labelled as such using an approved bar code label. Each unit should be monitored using a radiation-sensitive device, and the result permanently recorded, manually or by computer.
1.2.5 Ensuring irradiated components are supplied and transfused
Patients at risk of TA-GvHD should be made aware of their need for irradiated blood components and provided with appropriate written information and an alert- card for clinical staff. We endorse the recommendations from SHOT (www.shotuk.org) relating to improved clinical and laboratory awareness, documentation and communication of special requirements for transfusion, including irradiated components. Initiatives to improve laboratory and clinical information management systems ( including IT links with Pharmacy and diagnostic services to highlight “at risk” patients) should be incorporated into local policies and regularly audited. Poor communication between centres involved in “shared care” of patients is a well reported hazard and the development of a standardised national system for recording and transferring details of special transfusion requirements is an urgent requirement. In this Trust, patients requiring irradiated blood components will be sent a letter including an NHSBT information leaflet and alert card. This will be sent from Blood Transfusion.
1.3 Aim/purpose
To prevent transfusion associated graft-versus-host disease.
1.4 Patient/client group
As above