A blood transfusion replaces loss of blood due to injury and surgery, and replenishes supplies when disease affects the body's ability to produce blood. They are performed on 5 million Americans each year, according to the National Heart Lung and Blood Institute, or NHLBI. Blood transfusions are beneficial and life-saving; in rare instances, however, side effects from a blood transfusion are possible.
The most common side effect of a blood transfusion is fever, according to MayoClinic.com. White blood cells in the transfusion can cause this side effect, which can be accompanied by shaking and chills. A fever that develops during the transfusion or shortly thereafter is called a febrile reaction. Although a febrile reaction is usually harmless, the blood transfusion is commonly stopped while a more serious cause is ruled out.
Acute Hemolytic Reaction
According to the NHLBI, acute hemolytic transfusion reactions are serious but rare. This reaction happens when the blood types of the donor and recipient do not match. The body destroys the new blood cells, and in the process produces substances that damage the kidneys. Symptoms include fever, chills, dark urine, pain in the chest or back and nausea.
Delayed Hemolytic Reaction
A delayed hemolytic reaction happens when the body slowly attacks the newly-transfused blood cells days or weeks after a transfusion. There are usually no symptoms except a falling blood count as the blood cells are destroyed, according to the American Cancer Society. This reaction is usually related to having had several transfusions in the past; a blood test prior to the transfusion can prevent this reaction.
According to Merck Manuals Online Medical Library, graft-vs-host disease, or GVHD, occurs when white blood cells from the donor's blood attack the tissues of the transfusion recipient. People with weakened immune systems are at highest risk. GVHD is almost always fatal. Symptoms of fever, diarrhea and rash appear within a month of a transfusion, explains the NHLBI. GVHD can be prevented by irradiating blood before transfusion.
Transmission of infection occurs rarely, explains the NHLBI. Possible infections that can be passed on through blood transfusion include HIV, hepatitis B and C, and Variant Creutzfeldt-Jakob disease, vCJD, a rare and fatal brain disorder described as a human form of mad cow disease. According to Merck, cytomegalovirus, syphilis, malaria and human T-cell lymphotropic virus 1, a virus that causes adult T-cell lymphoma/leukemia, are rare but possible.