A 65-year-old woman developed a fever of 102F (38.9C) shortly after receiving a transfusion. What is the most likely cause of her symptoms?

The development of a fever shortly after a blood transfusion is often indicative of a febrile transfusion reaction. This type of reaction is mainly caused by the recipient's immune response to the white blood cells or cytokines present in the transfused blood components. In patients, especially those who have received multiple transfusions, the presence of these components can trigger the release of pyrogens, leading to fever and chills.

In this case, the woman's fever of 102°F (38.9°C) combined with the timing of her symptoms occurring shortly after the transfusion aligns with the classic presentation of a febrile transfusion reaction. This reaction typically manifests as a rise in temperature and is generally considered a benign complication, though it does require monitoring and management.

Other potential causes of fever post-transfusion, such as transfusion of bacterially contaminated blood, would typically present with additional symptoms such as hypotension, rigor, and more severe reactions that develop more rapidly. Congestive heart failure is associated with symptoms like shortness of breath and increased blood pressure, rather than isolated fever. An anaphylactic transfusion reaction usually occurs almost immediately and presents with symptoms like urticaria, angioedema, or respiratory distress rather than just a