Irradiation of donor blood is performed to prevent which adverse effect?

Irradiation of donor blood is a critical intervention performed specifically to prevent transfusion-associated graft-vs-host disease (TA-GvHD). This adverse effect occurs when transfused donor lymphocytes, which are not adequately eliminated from the blood components, recognize the recipient's tissues as foreign and mount an immune response against them. This is particularly dangerous in immunocompromised patients, such as those undergoing certain cancer treatments or with specific congenital immunodeficiencies.

By subjecting donor blood to irradiation, the viable lymphocytes present are rendered incapable of proliferating, thus effectively eliminating the risk of TA-GvHD. This practice is particularly important in certain patient populations who are more vulnerable to this condition.

The other adverse effects listed are not mitigated by irradiation. For example, febrile transfusion reactions are generally due to recipients' immune responses to soluble factors or white blood cells rather than donated lymphocytes. Cytomegalovirus infection can be managed through leukocyte reduction rather than irradiation, and transfusion-related acute lung injury (TRALI) is not directly prevented by this method but rather involves reactions typically associated with donor antibodies reacting to recipient leukocytes. Therefore, irradiation serves a specific purpose in the context of transfusion medicine, focusing on the