What is the definition or description of: transfusion reaction?

Fever,sob: A transfusion reaction is a bodily response to the blood being infused. Mild symptoms may include fever , arthralgias. More serious symptoms are shortness of breath and chest pain . Occasionally acute pulmonary edema ensues attributed to acute lung injury(tralii- lung injury). Other organs involved in transfusion reactions include kidney problems.

Many: There are many types of transfusion reactions - one caused by ABO incompatibility, which we don't see often because everyone checks for that, and another, more general one, caused by cytokines secreted by the body in response to the foreign matter.