Abstract:
Bone marrow transplantation (BMT) is a special therapy for patients whose bone
marrow has been damaged or destroyed, due to pathological causes and / or disease, whereby
healthy bone marrow cells are transfused into patients after their own unhealthy bone marrow
has been removed. BMT patients require extensive and specialized transfusion support with
red cells (RBCs), platelets and (sometimes) granulocytes until the transplanted marrow begins
to produce new blood cells. During this period, BMT patients are at risk for a variety of
transfusion-related sequelae, including alloimmunization against HLA antigens.
Twenty BMT patients at Siriraj Hospital were followed up for collection of serum
samples from the date of admission through till hospital discharge and all serum samples were
tested for HLA class I antibodies by using lymphocytotoxicity assay against a panel of 70-80
HLA typed lymphocytes. During admission at the hospital, all patients were assessed for the
response to platelet transfusion by calculating corrected count increments.
The result showed that from 20 patients, HLA class I antibodies were detected in 9
patients, five of whom were HLA-alloimmunized before admission on the study and all five
patients developed platelet refractoriness. The remaining four patients developed antibodies
during the study period, however, only one patient out of four developed platelet
refractoriness. In summary, this data confirms that BMT patients receiving multiple red cells
and platelet transfusion are at risk of producing antibodies against HLA class I antigens which,
in turn, may lead to problems hindering transfusion support, especially of platelets.