The risk of contracting an infectious disease from blood transfusion.

In the general population, the likelihood of an individual receiving a transfusion has been calculated to be about 0.89% per year, increasing dramatically with age. Massive intraoperative hemorrhage from trauma, cardiopulmonary bypass, and orthotopic liver transplantation need substantial replacement therapy. In renal transplantation, blood transfusion is a debated induction tool for specific allograft tolerance, since it causes a nonspecific down-regulation of immune function. In transplantations, in humoral immune deficiencies, in hematological disorders, and in HIV infection, the intravenous immunoglobulin prophylaxis may alter the monocyte/macrophage system host immunity and immune surveillance against infection, tissue or cell damage, and malignancy. Some persons, like Jehovah's Witnesses, object to transfusion of blood products, posing ethical and practical issues concerning treatment of blood disorders, transplantation, and trauma. In this review we examined the actual risk of contracting an infectious disease from an allogeneic blood transfusion to contribute to an uneasy decision-making process. We have found that the procedure is presently considerably safe.