Teaching our incoming haematology doctors today about transfusion in haematology patients. So who needs irradiated blood and why? A #blooducation🧵
All blood in the UK is leucocyte reduced (except granulocytes, but that’s another story). Despite this, a unit of red cells or platelets can have around a million residual white cells, mostly lymphocytes.
(for the #haemSpRs, that’s < 5 x 10^6 leucocytes/unit in > 99 % of units and < 1 x 10^6 leucocytes/unit in > 90% of units, both with 95% statistical confidence)
nhsbtdbe.blob.core.windows.net/umbraco-assets…
nhsbtdbe.blob.core.windows.net/umbraco-assets…
In immunocompetent individuals, residual lymphocytes in the component will be destroyed by the recipient’s immune system (you may see this as a “febrile non haemolytic transfusion reaction” FNHTR)
In patients who can’t recognise those incoming lymphocytes as being foreign, the lymphocytes may engraft. As the patient and recipient are not closely HLA matched, the risk of graft vs host disease is high, and is catastrophic when it happens. Mortality >95%.
Patients at risk either
A.Have gross T cell deficiencies
B.Have a close HLA relationship with the donor – close enough that the foreign lymphocytes can go under the radar
A.Have gross T cell deficiencies
B.Have a close HLA relationship with the donor – close enough that the foreign lymphocytes can go under the radar
Category A includes patients
1.Undergoing chemo with T cell depleting agents. Classically purine analogues e.g. fludarabine
2.Undergoing stem cell transplant –allo- or autologous + CAR-T (includes prior to harvest)
3.With Hodgkin lymphoma
4.With congenital T cell deficiency
1.Undergoing chemo with T cell depleting agents. Classically purine analogues e.g. fludarabine
2.Undergoing stem cell transplant –allo- or autologous + CAR-T (includes prior to harvest)
3.With Hodgkin lymphoma
4.With congenital T cell deficiency
5.With very immature immune system e.g. fetuses
6.Who are neonates who underwent intrauterine transfusion before birth or are having an exchange transfusion
Stem cell transplants do NOT require life long irradiation. Check out the BSH guidelines for more detail.
6.Who are neonates who underwent intrauterine transfusion before birth or are having an exchange transfusion
Stem cell transplants do NOT require life long irradiation. Check out the BSH guidelines for more detail.
Category B includes patients receiving transfusions from
1.A first or second degree relative
2.An HLA matched donor (e.g. HLA selected platelets)
Updated BSH guidelines came out in 2020.
onlinelibrary.wiley.com/doi/full/10.11…
1.A first or second degree relative
2.An HLA matched donor (e.g. HLA selected platelets)
Updated BSH guidelines came out in 2020.
onlinelibrary.wiley.com/doi/full/10.11…
Did you know:
1.Patients having alemtuzumab and ATG for non haematological conditions (e.g. vasculitis, solid organ transplant) do not need irradiated blood?
2.Frozen thawed red cells don’t need to be irradiated (no viable lymphocytes)
1.Patients having alemtuzumab and ATG for non haematological conditions (e.g. vasculitis, solid organ transplant) do not need irradiated blood?
2.Frozen thawed red cells don’t need to be irradiated (no viable lymphocytes)
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