What does it mean if a patient has antibodies that react with transfused blood cells?

If a patient has antibodies that react with transfused blood cells, it indicates that the patient's immune system has identified the transfused cells as foreign. This immune response can lead to hemolytic reactions, where the body attacks and destroys the transfused red blood cells. Hemolytic reactions can vary in severity, potentially causing symptoms ranging from fever and chills to more serious complications, such as acute hemolytic transfusion reactions, which can be life-threatening.

Understanding the implications of antibody presence is critical in transfusion medicine. It underscores the importance of thorough blood typing and crossmatching before transfusions to prevent adverse reactions. The presence of these antibodies essentially signals that the patient has been sensitized to specific blood group antigens and requires careful selection of compatible blood products to avoid adverse immunological responses.